‘ 4.. . To??? 7 . .. ......s.. MICHIGAN STATE UNIVERSITY LIBRARIES llllllll llllll 3 1293 00073 0436 i LIBRARY Michigan State University This is to certify that the dissertation entitled Cflmatografific Analysis of the Devekptmtal 813m ofRJminginPreRinolBoysaIfiGers presented by JoyE. Kiger has been accepted towards fulfillment of the re%uirements for or o ' degree in Major professor Date 7 / Y may-mm- » . ‘ r1 m, » r - 042771 MSU LlBRARlES RETURNING MATERIALS: Place in book drop to remove this checkout from your record. FINES will be charged if book is returned after the date stamped below. * fee Z-Qrenfia '1'. 4. n/ H slim CINEMATOORAPHIC ANALYSIS OF THE DEVELOPMENTAL STAGES OF RUNNING IN PRESCHOOL BOYS AND GIRLS by Jay E. Kiger A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Division of Physical Education and Exercise Science School of Health Education, Counseling Psychology, and Human Performance 1987 lif Ham Fund “H =7"; 9 5.2.; __ as ABSTRACT CINEMATOGRAPHIC ANALYSIS OF THE DEVELOPMENTAL STAGES OF RUNNING IN PRESCHOOL BOYS AND GIRLS By Joy E. Kiger Motor development researchers have identified age related, but not age dependent, changes for key characteristics observed in developing fundamental skills of children. In the skill of running the key descriptive characteristics are generally synonymous with kinematic variables investigated by age or grade level in biomechanics studies. However, biomechanical analysis of the developmental stages of various fundamental motor skills has yet to be done. This interdisciplinary study was undertaken to explore the potential for using biomechanical research techniques to determine the extent and significance of mechanical differences observed in developing running skill. Its purpose was to identify which specific variables differed among the four developmental stages of running as well as between gender performances. Simultaneous sagittal and frontal view high speed cinematography was used to analyses selected kinematic variables which represented the distinguishing characteristics of the four developmental stages of running. Seven major areas were investigated: (a) running descriptors and selected anthropometric measures; (b) segmental inclination at selected points during the running cycle; (c) distance between the hr downward vertical projection of the body's center of gravity and the foot at touchdown; (d) sequence of peak angular velocity for leg segments; (e) midline—limb segment center of gravity distance at selected points during the running cycle; (fl temporal analysis; and (gllimb segment displacements, both linear and angular. Variables were analyzed for each leg to observe differences between right and left limb actions. Statistical significance for stage effect was obtained for trochanteric height, running velocity, right shank at touchdown, right forearm at humerus maximum backward position, and angular displacement of the right forearm, and for gender effect in the left shank at maximum leg extension. Developmental trends across stages were identified in almost all areas investigated. Symmetrical performance was not expected, but right-left variations were consistently larger among stage two and stage three runners than stage one and four runners. Despite thelimited statistical significance for stage effect, the data revealed that the use of biomechanical research techniques to investigate developmental stages holds promise for providing invaluable insight into the development of fundamental motor skills in young children. To my most inspirational teachers - my students. ”W: to.“ llesti Nil 1 ACKNOWLEDGEMENTS God gave me a dream; motivated me to set a goal; and He kept stimulating me to succeed.* Nith perseverance and assistance a dream can be achieved. I would like to take this opportunity to acknowledge those individuals who influenced or assisted with my attempt of a project of this magnitude. First, to my parents for their love and financial support over the years. Their faith was a great source of strength throughout the struggle. To the children in the Northmont City Schools, Englewood, Ohio, and particularly the students at Englewood Hills Elementary School. For many years the children were my teachers as much as I was their teacher. They especially stimulated my desire to obtain a deeper understanding of the development of motor skill performance in young children. To Dr. Nadine Zimmerman and Dr. Sharon Plowman of Northern Illinois University. These two individuals convinced me to seek out the advanced degree and teach teachers as well as young children. To Dr. Robert Shapiro, (University of Kentucky, formerly at Northern Illinois University) for introducing me to the potential of biomechanics research techniques to investigate motor development questions. His term assignment really did become a dissertation. To my dissertation committee; Dr. Crystal F. Branta, Chair, Dr. Betsy Becker, Dr. John Haubenstricker, and Dr. V. Dianne Ulibarri, V with Special acknowledgement to Dr. Ulibarri's willingness to provide access to the facilities, equipment, and biomechanics software program. An immense thank you to both Dr. Branta and Dr. Ulibarri for reading all the extra drafts it took to blend the writing styles of the two disciplines. To the "movie stars“ and their parents for their enthusiasm and cooperation. And to Mary, Trish, A1, Sharon, and Dianne for their assistance in "making a movie“. To Dr. J. Amoli (Acting Director, 1986-87, Office of Research Consultation) Michigan State University, and Alan Hopfer (Programmer/ Analyst I, Office of Computing and Telecommunications) University of Missouri—St. Louis. Their ready answers to statistical programming questions were invaluable. To Dr. Vern Seefeldt (Director, Youth Sports Institute Michigan State University) and Dr. Virginia Fortney (Biomechanics Laboratory, Pennsylvania State University) for making it possible to obtain some of the impossible to find resources. To Dr. Marty Ewing (Youth Sports Institute, Michigan State University) for her willingness to serve as a "pinch fielder“ of questions and concerns. Her quiet encouragement was greatly appreciated. To my colleagues and students in the Department of Physical Education, School of Education, University of Missouri—St. Louis for their encouragement and patience. Special thanks to Kathy Haywood for providing an interdisciplinary reaction to concerns and questions. To the folks at Movement Arts, Lansing, Michigan, for developing and challenging my martial art skills and for providing quiescence vi amid the rigors of academia. To Susan for assisting with the anthropometric measurements photography and continuous encouragement. Her many long distant calls of support kept me going. To Jason and Jeffrey for being super photo models and providing amusing study breaks. Your loving “squeezes" were appreciated far more than you will ever realize. * Paraphrased from Schuler, R. H. (1983). Tough minded faith for tender hearted people (p.24). Nashville, Tenn.: Thomas Neslon. LIST OF LIST OF CHAPTER TABLE OF CONTENTS TABLES............ ..... .. FIGURES......................... IllIlIIllIII-I'll...-lllllllllIIIl INTRODUCTION............ The Research Problem........... Terminology ....... ..... The Research Hypotheses..................... Kinematic Variables............................. Predicted Developmental Trends......................... Hypotheses............................................. The Scope of the Study.......... Limitations................ ........ Assumptions............................. IIIIIIIIIIII'IIll-lllllllI REVIEW OF LITERATURE...................... Developmental Stage Theory..... Biological - Psychological Origins........ Stage Theory Applied to Motor Development....... Early Studies of Motor Development............. Studies of Developmental Stages in Fundamental Motor Skills.................. ........ The Development of Running Form........................... Developmental Stages of Running........................ Developmental Biomechanical Studies of Running.. The Mature Running Form............................... Components of the Running Cycle............. Leg Action - Drive Interval.................... Leg Action - Recovery Interval...................... Arm Action.................... ...... Body Position and Displacement........ Effects of Speed (Velocity) Changes.................... Characteristics of Mature Running Form................. Summary........................... viii 28 29 33 34 38 41 45 52 57 58 59 62 64 63 69 TABLE OF CONTENTS (CONTINUED) CHAPTER III METHODOLOGY............................... Subjects.................. Testing Procedures............. Anthropometric Measurements.................... Cinematographic Procedures............................. Data Reduction and Analysis...................... Film Analysis................... Research Design. ........ ..................... Statistical Analysis............ lean-Inn- Illlllllll'llllllitllll Ill-III.- lllllulll'IIIIlIIllIIlI DISCUSSION OF RESULTS..................................... Running Descriptors............................. Segmental Inclinations................. Leg Drive Interval — Touchdown............. Leg Drive Interval - Takeoff......................... Leg Drive Interval - Maximum Leg Extension.......... Trunk Inclination at Touchdown and Takeoff............. Leg Recovery Interval - Minimum Knee Angle............. Leg Recovery Interval — Maximum Thigh Segment Height. Arm Segment Inclinations............................. Body C. O. G. - Foot Distance at Touchdown.................. Sequence of Peak Angular Velocity in the Legs............. Drive Interval......................................... Recovery Interva1................................... Drawn Midline - Limb Segments Centers of Gravity Distance. Temporal Analysis......................................... Limb Segments Displacements.......................... Linear Displacement of Centers of Mass of Leg Segments. Angular Displacement of Leg Segments................ Linear Displacement of Centers of Mass of Arm Segments. Angular Displacement of Arm Segments................... Summary of Results........................................ Reflections on the Analyses Process....................... V CONCLUSION AND RECOMMENDATIONS............................ Conclusion...................... Recommendations................... Page 75 75 77 77 82 82 94 APPEI .liIr-LF lllllfll TABLE OF CONTENTS (CONTINUED) Ease APPENDICIESIIIIIII'IIIII-Alli!III-llllllllllIIlllualll nnnnnn unnu- A Early Childhood Motor Skills Development Study Tables on Running.............................................. £83 Parental Information............................. ..... .. 190 Anthropometric Measurement Procedures................... 193 Data Collection Forms................................... 206 Raw Data Tables......................................... 209 Statistical Analyses Tables................... ..... ..... 233 ‘nmcom BIBLIOGRAPHY-I-uuuno-Inna-unlea-u-IIInc-cue.cannula-uuungno-unun. 260 General References........................................ 271 LIST OF TABLES Table Page 1. Summary of Studies on the DeveIOpment of Running in Children. 44 10. ll. 12. 13. 14. IS. . Analysis for Stage Effect on Selected Running Measurements. . Analysis for Gender Effect on Selected Running Measurements.. . Summary of Major Developmental Studies on the Biomechanics IIIIII COICII‘IIII 55 . Summary of Running Factors that Change with Increases in of Running in Children..... Speed (Velocity)..... . Analysis for Stage Effect on Selected Anthropometric Measures (cm).......... III IIIII IIIIIIIIICI‘IOII 97 . Analysis for Gender Effect on Selected Anthropometric Measures (cm)........ I. 98 98 Analysis for Stage Effect on Selected Right and Left Leg Running Measurements..................... .... . .............. 100 Analysis for Gender Effect on Selected Right and Left Leg Running Measurements.............. ...... .. ................... 101 Analysis of Running Velocity (m/s) from Subject Selection Testing (April) and from Film (May)........ ..... ............. 103 Comparison of Running Speeds (m/s) by Developmental Stage and Age from Selected Research ((n) = Number of Subjects).... 104 Running Indicies by Age (Fortney, 1980) Compared to Running Indices by Stage (Kiger, 1987).. .......................... 106 Correlations for Selected Running Descriptors .......... . ..... 107 Comparison of Mean Actual Leg Joint Angles (degs) at Maximum Leg Extension and Takeoff by Stage........... ........ 118 Sequence of Peak Angular Velocities for Leg Extension During the Drive Interval (ms = midsupport phase, to = takeoff phaSE).............¢. lllll ICIIIIOIOIIIIIIOII. IIIIIII Ill IIIIII 135 xi LIST OF TABLES Table Page 1. Summary of Studies on the Development of Running in Children. 44 2. Summary of Major Developmental Studies on the Biomechanics of Running in Children............. .......................... 55 3. Summary of Running Factors that Change with Increases in Speed (Velocity)............................................. 7O 4. Analysis for Stage Effect on Selected Anthropometric Measures ................. 97 (cm)........................................ 5. Analysis for Gender Effect on Selected Anthropometric Measures (cm)................................................ 97 6. Analysis for Stage Effect on Selected Running Measurements... 98 7. Analysis for Sender Effect on Selected Running Measurements.. 98 8. Analysis for Stage Effect on Selected Right and Left Leg Running Measurements......................................... 100 9. Analysis for Gender Effect on Selected Right and Left Leg Running Measurements. ............................... ........ 101 10. Analysis of Running Velocity (m/s) from Subject Selection Testing (April) and from Film (May).......................... 103 11. Comparison of Running Speeds (m/s) by Developmental Stage and Age from Selected Research ((n) = Number of Subjects).... 104 12. Running lndicies by Age (Fortney, 1980) Compared to Running Indices by Stage (Kiger, 1987)............................... 106 13. Correlations for Selected Running Descriptors................ 107 14. Comparison of Mean Actual Leg Joint Angles (degs) at Maximum Leg Extension and Takeoff by Stage................... 118 15. Sequence of Peak Angular Velocities for Leg Extension During the Drive Interval (ms = midsupport phase, to = takeoff phase).................................................... ... 135 LIST OF TABLES (CONTINUED) Ta le Page 16. Sequence of Peak Angular Velocities for Leg Flexion During the Recovery Interval (ft = follow through phase, fs = forward swing phase). ...... . .................. . ............. 137 Appendix A: Early Childhood Motor Skills Development Study Tables on Running A1 Percent of Children Performing at the Various Stages of Running by Age and Gender..... ...................... ........ 183 A2 Percentile Ranks for Running with Transitions Separated from Whole Stage Performance by Age and Gender. ..... . ............ 184 A3 Mean 15- Yard (13. 71 Meter) Run Times in Seconds and Speeds by Age and Gender.. ........ . .. ..... . ...................... 185 A-4 Mean 30- Yard (27. 42 Meter) Run Times in Seconds and Speeds by Age and Gender. ....... ... .. . . . ............ . 186 A—S Percentile Ranks for 30-Yard (27.42 Meter) Run Time in Seconds by Age and Sender....... ............ . ............. . 187 A-b 30- Yard Run Times in Seconds and Speeds by Stage, Age, and Gender ..... . ..... ........ . ..................... . ......... 188 Appendix E: Raw Data Tables E~1 Subject Anthropometric Measurements .................. . ...... 209 E-2 Subject Running Descriptors.......... ...... . ................ 210 E-3 Segmental Inclinations (deg) for Right and Left Touchdown by Stage and Gender.......... ............ .. . . ... 211 E-4 Segmental Inclinations (deg) for Right and Left Maximum Leg Extension by Stage and Gender ............ ... ............ 212 E-S Segmental Inclinations (deg) for Right and Left Takeoff by Stage and 8ender................ ................... .... ..... 213 5‘6 Segmental Inclinations (deg) for Right and Left Minimum Knee Angle by Stage and Gender .............................. 214 LIST OF TABLES (CONTINUED) Table Page Appendix E (Continued) E-7 Segmental Inclinations (deg) for Right and Left Maximum 215 Thigh Segment Height by Stage and 8ender.................... E-S Segmental Inclinations (deg) for Right and Left Arms at Humerus Maximum Forward Swing and Maximum Backward Swing by Stage and 8ender............................................ 216 E-9 Drawn Midline - Segment Center-of-Gravity Distance (cm) at Touchdown by Stage and Gender............................... 217 E-10 Drawn Midline - Segment Center-of-Gravity Distance (cm) at Takeoff by Stage and Gender................................. 218 E-11 Drawn Midline - Segment Center-of—Bravity Distance (cm) at Minimum Knee Angle by Stage and 8ender...................... 219 E-12 Drawn Midline - Segment Center-of—Gravity Distance (cm) at 220 Maximum Thigh Segment Height by Stage and 8ender............ 8—13 Linear Displacement (cm) of Centers of Mass for Leg Segments from Touchdown to Takeoff by Stage and 8ender...... 221 E-14 Linear Displacement (cm) of Centers of Mass for Leg Segments from Takeoff to Minimum Knee Angle by Stage and 8ender...................................................... 222 E-15 Linear Displacement (cm) of Centers of Mass for Leg Segments from Minimum Knee Angle to Maximum Thigh Segment Height by- Stage and Gender...................... .... ....... 223 E-16 Linear Displacement (cm) of Centers of Mass for Leg Segments from Maximum Thigh Segment Height to Touchdown by Stage and 8ender................ .. ................ .... . 224 E-17 Linear Displacement (cm) of Centers of Mass for Arm Segments from Humerus Maximum Forward to Maximum Backward Position by Stage and Gender................................ 225 5-18 Angular Displacement in Degrees (Radians) of Leg Segments from Touchdown to Takeoff by Stage and Gender............... 226 E-19 Angular Displacement in Degrees (Radians) of Leg Segments from Takeoff to Minimum Knee Angle by Stage and Gender...... 227 xiii LIST OF TABLES (CONTINUED) Table Page Appendix E (Continued) E~20 Angular Displacement in Degrees (Radians) of Leg Segments from Minimum Knee Angle to Maximum Thigh Segment Height by Stage and Eender............................... ......... .. 228 E 21 Angular Displacement in Degrees (Radians) of Leg Segments from Maximum Thigh Segment Height to Touchdown by Stage and Gender................................ .. ... . ........... 229 E 22 Angular Displacement in Degrees (Radians) of Arm Segments from Humerus Maximum Forward to Maximum Backward Position by Stage and 8ender.................................... ..... 230 E-23 Distance (cm) Between the Downward Vertical Projection of the Total Body Center of Gravity and the Support Foot and Right and Left Touchdown by Stage and 8ender............ .. 231 8-24 Temporal (5) Observations for One Running Cycle of Right and Left Leg by Stage and Gender. ... ... .. ................ 232 Appendix F: Statistical Analyses Tables F-l Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Touchdown... ......... ...................... 233 F-2 Analysis for Gender Effect on Segmental Inclinations (deg) at Right and Left Touchdown.................................. 233 F-S Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Takeoff............. ..... ... . ...... . ...... 234 F-4 Analysis for Gender Effect on Segmental Inclinations (deg) at Right and Left Takeoff.............................. ...... 234 F-S Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Maximum Leg Extension.......... ..... . ..... . 235 F-b Analysis for Gender Effect on Segmental Inclinations (deg) at Right and Left Maximum Leg Extension...................... 235 F‘7 Analysis for Stage Effect on Trunk Inclination (deg) at ... ..... . 236 Right and Left Touchdown and Takeoff.... xiv ('1) Hi LIST OF TABLES (CONTINUED) Table Page Appendix F (Continued) F-B Analysis for Gender Effect on Trunk Inclination (deg) at Right and Left Touchdown and Takeoff ......................... 236 F-9 Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Minimum Knee Angle ...... . .......... ........ 237 F-lO Analysis for Gender Effect on Segmental Inclinations (deg) at Right and Left Minimum Knee Angle ......................... 237 F-11 Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Maximum Thigh Segment Height ............... 238 F-12 Analysis for Gender Effect on Segmental Inclinations (deg) at Right and Left Maximum Thigh Segment Height ............ ... 238 F—13 Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Humerus Maximum Forward and Backward.. ..... 239 F-14 Analysis for Gender Effect on Segmental Inclinations (deg) at Right and Left Humerus Maximum Forward and Backward..... 240 F-15 Analysis for Stage Effect on the Distance (cm) Between the Downward Vertical Projection of the Total Body Center of Gravity and the Support Foot at Right and Left Touchdown ..... 241 F-16 Analysis for Gender Effect on the Distance (cm) Between the Downward Vertical Projection of the Total Body Center of Gravity and the Support Foot at Right and Left Touchdown..... 241 F-17 Analysis for Stage Effect on the Distance (cm) Between Drawn Midline and Limb Segments Centers of Gravity for Right and Left Tauchdown.......... ........................ . ............ 242 F-18 Analysis for Gender Effect on the Distance (cm) Between Drawn Midline and Limb Segments Centers of Gravity for Right and Left Touchdown ..... . ................................... . 243 F-19 Analysis for Stage Effect on the Distance (cm) Between Drawn Midline and Limb Segments Centers of Gravity for Right and Left Takeoff. ............................................... 244 F-20 Analysis for Gender Effect on the Distance (cm) Between Drawn Midline and Limb Segments Centers of Gravity for Right and Left Takeoff...... ...... . ..... ... ..... . ............... 245 xv LIST OF TABLES (CONTINUED) Table Page Appendix F (Continued) F 21 Analysis for Stage Effect on the Distance (cm) Between Drawn Midline and Limb Segments Centers of Gravity for Right and . ... 246 Left Minimum Knee Angle..... ...... ........... F-22 Analysis for Gender Effect on the Distance (cm) Between Drawn Midline and Limb Segments Centers of Gravity for Right 247 and Left Minimum Knee Angle.......... .. F 23 Analysis for Stage Effect on the Distance (cm) Between Drawn Midline and Limb Segments Centers of Gravity for Right and Left Maximum Thigh Segment Height............................ 248 F-24 Analysis for Gender Effect on the Distance (cm) Between Drawn Midline and Limb Segments Centers of Gravity for Right 249 and Left Maximum Thigh Segment Height........................ F—25 Analysis for Stage Effect on Time (s) in Support and Nonsupport for Right and Left Leg Running Cycles............. 250 F-26 Analysis for Stage Effect on Total Time (s) in Support and Nonsupport............... ........................ 250 F-27 Analysis for Gender Effect on Time (s) in Support and Nonsupport for Right and Left Leg Running Cycles............. 251 F-28 Analysis for Gender Effect on Total Time (s) in Support and Nonsupport............ ........... 251 F 29 Analysis for Stage Effect on Percent of Cycle in Support and Nonsupport for Right and Left Leg............................ 252 F-30 Analysis for Stage Effect on Total Percent of Cycles in Support and Nonsupport....................................... 252 F-31 Analysis for Gender Effect on Percent of Cycle in Support and Nonsupport for Right and Left Leg............................ 253 F-32 Analysis for Gender Effect on Total Percent of Cycles in Support and Nonsupport................... ................. 253 F-33 Analysis of Stage Effect on Linear Displacement (cm) of Centers of Mass of Leg Segments for Selected Periods During Dne Complete Running Cycle for Each Leg...................... 254 F-34 Analysis of Gender Effect on Linear Displacement (cm) of Centers of Mass of Leg Segments for Selected Periods During One Complete Running Cycle for Each Leg...................... 255 xvi LIST OF TABLES (CONTINUED) Table Appendix F (Continued) F-35 Analysis of Stage Effect on Angular Displacement in Degrees of Leg Segments for Selected Periods During One (Radians) Complete Running Cycle for Each Leg... Analysis of Gender Effect on Angular Displacement in Degrees (Radians) of Leg Segments for Selected Periods During One Complete Running Cycle for Each Leg....... .......... F-36 Stage Effect on Forward-Backward Swing Linear F-37 Analysis for (cm) of Centers of Mass of Arm Segments......... Displacement Gender Effect on Forward-Backward Swing Linear F-38 Analysis for (cm) of Centers of Mass of Arm Segments......... Displacement Stage Effect on Forward-Backward Swing Angular F-39 Analysis for in Degrees (Radians) of Arms.................... Displacement Gender Effect on Forward-Backward Swing Angular F-4O Analysis for in Degrees (Radians) of Arms.................... Displacement xvii figs: 256 257 258 258 259 Dr: 11. 51m I" F101 Figure L 2. (A - \1 a: Illustrations of the leg at Illustrations of the leg at Illustrations of the leg at interval..... Illustrations LIST OF FIGURES of predicted changes in segmental inclinations touchdown position.......... ....... ........... of predicted changes in segmental inclinations takeoff position.............................. of predicted changes in segmental inclinations minimum knee angle during the recovery of predicted changes in segmental inclinations of the thigh at maximum thigh segment height................. Illustrations of predicted changes in segmental inclinations of the humerus and forearm at maximum forward angular rotation of arm swing........................................ Illustrations of predicted changes in segmental inclinations of the humerus and forearm at maximum backward angular rotation of arm swing............................... ..... .... Initial attempts at running characterized by extreme high guard position of the arms and short, choppy steps without a true flight p . Description ( tracing of st Description ( eriod............................. ..... ......... Seefeldt, Reuschlein, & Vogel, 1972) and film age one run. Numbers indicate film frame....... Seefeldt, Reuschlein, & Vogel, 1972) and film tracing of stage two run. Numbers indicate film frame....... Description ( Seefeldt, Reuschlein, & Vogel, 1972) and film tracing of stage three run. Numbers indicate film frame..... Description ( Seefeldt, Reuschlein, & Vogel, 1972) and film tracing of stage four run. Numbers indicate film frame...... Appearance of the deVelopmental stages of running in preschool age children, independent of gender......... ..... .. Summary of the components of a running cycle...... ..... ...... Floor plan of filming area................................... xviii Page l7 19 20 23 24 42 47 4B 49 50 51 60 80 Figure 15. Numbering of designated end points of the body segments ...... 16. Segmental inclinations for analysis of joint angles during 20 2 22. 2 ... 04 ~40 O 3. LIST OF FIGURES (CONTINUED) the drive interval: (a) foot, (b) shank, (c) thigh........... Measurement of trunk inclination............................ Selected positions for lower extremity segmental inclination measurements for analysis during drive interval: (a) touchdown, (b) takeoff....................... ........ .... Measurement of segmental inclinations for analysis of minimum knee angle during the recovery interval............ Measurement of segmental inclination for analysis of maximum thigh segment height during the recovery interval............ Measurement of upper extremity segment inclinations for analysis of (a) humerus and (b) forearm at maximum backward and forward swing.................................. Measurement of the horizontal distance between the downward vertical projection of the body's center of gravity and the foot at touchdown................................. ........ ... Measurements for the relationship of segment center of gravity of the hands, forearms, humeri, thighs, shanks, and feet with the drawn midline (center line of progression)..... Film tracings of subjects at right and left touchdown........ Film tracings of subjects at right and left takeoff......... Film tracings of subjects at right and left maximum leg extension...................................... .......... ... Film tracings of subjects at right and left minimum knee angle....................................................... Film tracings of subjects at right and left maximum thigh segment height............................................... Sagittal film tracings of subjects at right humerus maximum forward and maximum backward................................. Frontal film tracings of subjects at right humerus maximum forward and maximum backward....................... ..... .... Page 8 (A 85 86 87 88 89 92 93 110 113 116 129 I30 LIST OF FIGURES (CONTINUED) Figure Page 31. Distance between downward vertical projection of body center of gravity and foot at right and left touchdown....... 132 Frontal film stick figures for comparison of the distance between the drawn midline and the segment centers of gravity at right and left touchdown.................................. 140 32 Frontal film stick figures for comparison of the distance between the drawn midline and the segment centers of gravity at right and left takeoff.................................... 142 33 Frontal film stick figures for comparison of the distance between the drawn midline and the segment centers of gravity at right and left minimum knee angle......................... 144 34 Frontal film stick figures for comparison of the distance between the drawn midline and the segment centers of gravity at right and left maximum thigh segment height............... 145 35 36. Graphic illustration of limb segment locations for right and left touchdown and takeoff ..... ........ ..... ................. 147 37. Graphic illustration of limb segment locations for right and left minimum knee angle and maximum thigh segment height. 148 38. Percent of total cycles in support and nonsupport by stage... 151 39. Percent of total cycles in support and nonsupport by stage and gender................................ ......... .......... 152 40. Percent of right and left cycles in support and nonsupport by stage and gender......... ............. ....... ...... ...... 153 41. Point of occurrence for selected events within one combined right~left running cycle for each leg by stage and gender.... 155 42. Linear displacement (cm and percent of standing height) of centers of mass of leg segments during one running cycle for each leg .................... .............................. 157 43. Angular displacement (dog) of leg segments during one running cycle for each leg................................... 160 44. Linear displacement (cm and percent of standing height) of centers of mass for humerus and forearm from humerus maximum forward position to humerus maximum backward position........ 163 N): LIST OF FIGURES (CONTINUED) Figure Page 45. Angular displacement (deg) of humerus and forearm from humerus maximum forward position to humerus maximum backward position............ ..... ..................... ..... 165 Chapter I Introduction The development and complexity of coordinated movements, both animal and human, have intrigued researchers for ages. The investigation of movement, however, had been limited to direct observa— tion until the advent of cinematography. Early cinematographic work by Muybridge (1887/1955, 1887/1957) and Marey (1895) established methods for studying movement that continue to expand with advancements in cine- matography. During the 1920‘s, 1930’s, and 1940's child psychologists focused investigative efforts, both observational and cinematographic, on the development of human prehension and locomotion (Bayley, 1935; Gesell, 1928; H. M. Halverson, 1931; McGraw, 1945; Shirley, 1931) and fundamental motor patterns (Guttridge, 1935; Jenkins, 1930; McCaskill & Hellman, 1938; Wellman, 1937). These basic patterns involved locomotor, nonlocomotor, and manipulative movements of preschool and early elementary age children. Major characteristics in the maturation of physical_skills were often grouped into ‘Ievels,’ ‘phases,’ ‘steps,’ or 'stages,’ by adapting theories from developmental psychology. Espenschade and Eckert (1980) categorized the approaches by these early researchers as descriptive, kinesiological, or neuromuscular. l During the latter part of the 1950's, physical educators specializing in either motor development or biomechanics began to investigate the development of fundamental motor skills in children. These researchers observed that although young children of the same chronological age exhibited a wide variety of skill levels, the development of individual skills progressed in a rather predictable order from initial behaviors to high levels of proficiency. Their work specifically focused on the development of ‘normal’ fundamental motor skill patterns. These researchers have concentrated on either a battery of skills or on a single skill in their investigations. Several different approaches have been used by recent investigators in their studies. One approach continued the line of research used in the early studies by establishing achievement or performance scores by age or grade and gender (Frederick, 1977; Keogh, 1965; Morris, Williams, Atwater, & Nilmore, 1982).L,A second approach involved the categorization of skill performance as "good" or "poor" on the basis of a product score and then looking for the biomechanical differences between the two categories of performance (Beck, 1966; Dittmer, 1962);J A third approach involved filming children of selected ages and then looking for biomechanical differences among performances (Brown, 1978; Clouse, 1959; Fortney, 1964, 1980; Mersereau, 1974, 1977). A fourth aPproach required the filming of numerous children at various ages while they performed fundamental motor skills. These films were then analyzed for qualitative movement characteristics that depicted certain levels or Stages of development for each skill (Roberton & L. E. Halverson, 1984a, 1984b; Roberton, Williams, & Langendorfer, 1980; 53PP; 19801 SEEIEldt' —‘— I 11)) lung (sin Prev; 1). (1 ”dub," (Help, 111 Ml (Isms Reuschlein, and Vogel, 1972; Wild, 1938). Two different staging methods have emerged from this fourth approach, that of component parts developed by Roberton (1975, 1976, 1977, 1978a, 1978b, 1984) and that of total body configuration developed by Seefeldt et al. (1972) and later adapted by McGlenaghan and Gallahue (1978). Further research using the component parts and the total body configuration approaches has continued to refine and validate the earlier findings (Branta, Haubenstricker, Kiger, & Ulrich, 1984; Fountain, Ulrich, Seefeldt, & Haubenstricker, 1981; L. E. Halverson & Williams, 1985; Haubenstricker, Branta, & Seefeldt, 1983; Haubenstricker, Branta, Ulrich, Brakora, & E-Lotfalian, 1984; Hauben- stricker, Seefeldt, & Branta, 1983; Haubenstricker, Seefeldt, Fountain, & Sapp, 1981; S. Miller, Haubenstricker, & Seefeldt, 1977; Roberton, 1982; Roberton & L. E. Halverson, 1984; Roberton, Williams, & Langendorfer, 1980; Way, Haubenstricker, & Seefeldt, 1979). Research using the component parts and total body configuration approaches provides the preschool and elementary school physical educator with detailed information on the qualitative development of fundamental motor skills to complement the quantitative (distance, speed) information already available for age and gender. Except for the work reported by Branta et al. (1984), Fountain et 3L (1981), Glassow, L. E. Halverson, & Rarick (1965), and Hanenstricker et a1. (1984) evidence on the relationship between qualitative development and performance scores has been lacking in both the motor development and the biomechanics disciplines. Research results from the Early Childhood Motor Skills Development Study [Early 1“— Childhood] (1985) provide age percentile rankings in developmental stages for ten fundamental motor skills, as well as percentile rankings for running time, agility time, balance time, and jumping distance for children in the age range 2.5 to 5 years. This eight year, mixed longitudinal study provides unique data for establishing the link between the qualitative and quantitative performance scores. Yet, the link between process and product in the development of children's motor performance needs further research. Roberton (1972), Small (1979), and Wickstrom (1975) noted the potential of kinesiological techniques for examining the process-product link in understanding skill development. Garrett (1978) used the term "developmental biomechanics" to designate the use of biomechanical research techniques in the study of skill development. According to Garrett, developmental biomechanics holds promise for fulfilling the need in developmental research not only for further investigating the process of skill development, but also for providing more precise measures than the verbal descriptions of skill development provided in the past. By combining the research efforts of the motor developmentalist and the developmental biomechanist (not to mention the efforts of the child developmentalist, sport psychologist, sociologist, and physiologist), the potential for gaining a more thorough and precise understanding of motor skill development through synergistic research efforts is promising (Garrett, 1978). , L n on fun ill (EV! Show Sled Prey; ‘ still: of ,q, (11",, Nth, mien (each ”‘0; s The Research Problem Research conducted by motor developmentalists and developmental biomechanists on the development of fundamental motor skills, and on running in particular, has been limited to age/grade level or speed differences.l'For the skill of running, analyses have been limited mostly to leg movementsug As a result, a void exists in the data base regarding resultant arm movement patterns and important rotary movements that occur around the vertical axis of the body, as well as the role of these movements in the performance of the maturing skill. Furthermore, biomechanical differences among the identified developmental stages of fundamental motor skills have not been analyzed.’ With a kinematic analysis, physical educators would be able to ascertain more effectively the significance of the mechanical differences among the identified developmental stages of a skill. The developmental stages of’fundamental motor skills have been shown to be age related but not age dependent. TTn the case of running, speed also improves with the use of a more mature skill pattern» Previous biomechanical studies of running in children have attributed significant differences in selected kinematic variables to the function of age (Amano, Mizutani, & Hoskawa, 1983; Beck, 1966; Brown, 1978; Clouse, 1959; Dittmer, 1962; Fortney 1964, 1980; Mersereau, 1974, 1977; Smith, 1977). Early motor development research also attributed differences in running speed to age (Carpenter, 1942; Cunningham, 1927; Deach, 1951; Frederick, 1977; Glassow et al., 1965; Glassow & Kruse, 1960; Guttridge, 1939; Jenkins, 1930; McCaskill & Wellman, 1938; Wellman, 1937). A motor developmentalist investigating stage development would question whether the differences reported in earlier studies of running development were due to differences in age or to variations in running form, or stages, used by the children under investigation. It was, therefore, the purpose of this study to investigate selected kinematic variables representing the distinguishing characteristics of the developmental stages of running according to Seefeldt et al. (1972). Through the use of simultaneous sagittal and frontal plane high speed filming, the stated concerns and questions relative to arm and leg movement pattern differences among the developmental stages were addressed to provide quantitative information on the qualitative development of running behavior in young children. Such information is needed to verify quantitatively the significance of identified stage pattern differences and to provide base line kinematic data for future research in running stage development. This study focused on the four developmental stages of running as described by Seefeldt et al. (1972). The sequence of these stages has been verified through mixed longitudinal studies (Fountain et al., 1981; Branta et al., 1985; Early Childhood, 1985). The practical application of this running stage sequence was evident in its Use in the Test of Gross Motor Development (Ulrich, 1985). (on 5211 lhrm a) (uni ”We! Wellman, 1937). A motor developmentalist investigating stage development would question whether the differences reported in earlier studies of running development were due to differences in age or to variations in running form, or stages, used by the children under investigation. It was, therefore, the purpose of this study to investigate selected kinematic variables representing the distinguishing characteristics of the developmental stages of running according to Seefeldt et al. (1972). Through the use of simultaneous sagittal and frontal plane high speed filming, the stated concerns and questions relative to arm and leg movement pattern differences among the developmental stages were addressed to provide quantitative information on the qualitative development of running behavior in young children. Such information is needed to verify quantitatively the significance of identified stage pattern differences and to provide base line kinematic data for future research in running stage development. This study focused on the four developmental stages of running as described by Seefeldt et al. (1972). The sequence of these stages has been verified through mixed longitudinal studies (Fountain et al., 1981; Branta et al., 1985; Early Childhood, 1985). The practical application of this running stage sequence was evident in its use in the Test of Gross Motor Development (Ulrich, 1985). ‘g— I “1 d1 tun, lilo]; [dish lifgpt 112M231 Readers of interdisciplinary studies not familiar with the basic terminology of specific areas of study may have difficulty understanding the nomenclature used. For this reason, terminology used in the current study will be presented at this time. The terminology reflects the nomenclature prevalent in motor development and biomechanics and was compiled from the works of authors in each area of study (Beck, 1966; Clause, 1959; Dillman, 1975; Dittmer, 1962; Dyson, 1973; Fortney, 1980; Groves & Camaione, 1983; Hay, 1985; Haywood, 1986; Hopper, 1964; James & Brubaker, 1973; Northrip, 1983; Seefeldt, 1974; Seefeldt et al., 1972; Simonian, 1981; Slocum & James, 1968; Wickstrom, 1983). Motor Develogment is concerned with describing the underlying processes and the changes in movement behavior that occur over time which reflect the interaction of the human organism with its environment (Hayward, 1986; Wickstrom, 1983). Qualitative analysis in motor development involves the identification of characteristics in the form used for accomplishing a task, as well as the sequence in which various characteristics appear as the skill develops from the first rudimentary attempts to an efficient, mature performance. Quantitative analysis in motor development involves determining the direction, speed, and shape of developmental changes plotted on distance, speed, and acceleration curves. For example, in fundamental motor skills, quantitative analysis involves how fast (speed) a child runs a certain distance or how far (distance) a child may jump or throw or how many times a child can hit a target with an object (accuracy). Terminology Readers of interdisciplinary studies not familiar with the basic terminology of specific areas of study may have difficulty understanding the nomenclature used. For this reason, terminology used in the current study will be presented at this time. The terminology reflects the nomenclature prevalent in motor development and biomechanics and was compiled from the works of authors in each area of study (Beck, 1966; Clause, 1959; Dillman, 1975; Dittmer, 1962; Dyson, 1973; Fortney, 1980; Groves & Camaione, 1983; Hay, 1985; Haywood, 1986; Hopper, 1964; James & Brubaker, 1973; Northrip, 1983; Seefeldt, I974; Seefeldt et al., 1972; Simonian, 1981; Slocum & James, 1968; Wickstrom, 1983). Motor Development is concerned with describing the underlying processes and the changes in movement behavior that occur over time which reflect the interaction of the human organism with its environment (Hayward, 1986; Wickstrom, 1983). Qualitative analysis in motor development involves the identification of characteristics in the form used for accomplishing a task, as well as the sequence in which various characteristics appear as the skill develops from the first rudimentary attempts to an efficient, mature performance. Quantitative analysis in motor development involves determining the direction, speed, and shape of developmental changes plotted 0n distance, speed, and acceleration curves. For example, in fundamental motor skills, quantitative analysis involves how fast (speed) a child runs a certain distance or how far (distance) a child may jump or throw or how many times a child can hit a target with an object (accuracy). and life Ilrf, lille trans “khi Biomechanics is "concerned with the internal and external forces acting on the human body and the effects produced by these forces" (Hay, 1985, p.2). The science of biomechanics consists of two branches, kinematics and kinetics. Kinematics is concerned with describing the motion of a body or body parts using linear and angular displacements, velocities, and accelerations, without regard for the underlying causes of the movement. ‘Linear kinematics deals with the description of translation or linear motion while angular kinematics deals with rotation or angular motion. Kinetics is concerned with the forces that initiate, alter, and stop the motion of the body or body parts and involves the study of forces and moments. Qualitative analysis in biomechanics, as in motor development, involves visual and recorded observation to obtain descriptions of skill performance. Quantitative kinematic analysis also uses recording techniques and involves the measurement of position in space and calculations of linear and angular displacements, velocities, and accelerations of the body or body parts in question during skill performance. Quantitative kinetic analysis involves the measurement of the external forces that cause and affect the movement of the body or body parts in question during skill performance. Fundamental Motor Skills are common motor skills with specific patterns that involve two or more body segments and result in the transfer or reception of some external object or of the body itself. Examples of fundamental motor skills include running, jumping, throwing, catching, kicking, punting, skipping, and hopping. Pattern is an isolated movement which is confined to joints or 1L (Ul dri SUpp surf IUHSUI 1,, s“ segments too restrictive to be classified as a complete fundamental motor skill, i.e. an underarm pattern. Stage is a specific level of development in a fundamental motor skill containing certain identifiable characteristics. Egggg is a portion of a stage, such as the preparatory phase, the propulsive phase, or the follow through phase. Seguence is a series of movements which is highly predictable with reference to the performer and the skill. Running is a rapid form of locomotion characterized by periods of flight when the body is projected above the support surface alternately It consists of a smoothly coordinated, rhythmical series by each leg. of alternating periods of support and flight. Running Cycle is from touchdown on one foot until the same foot touches down again. In one running cycle, each leg moves through a drive and recovery interval as the total body passes through two periods of support and two periods of flight. Running Stride is from foot touchdown (or contact) with the supporting surface until touchdown (or contact) with the supporting surface by the opposite foot. Support Period is the duration of time the foot is in contact with the supporting surface. Flight Period is the duration of time when the body is nonsupported. Touchdown Position is the instant any part of the lead foot touches Also called contact. is the supporting surface. Midsupoort Position is the position when the lower leg (shank) 1% perpendicular to the running surface. Takeoff Position is the position where the foot is last observed in contact with the supporting surface. Maximum Leg Angle is the point at which the hip and knee joints of the support leg reach greatest extension and the concomitant ankle joint reaches greatest plantar flexion. Minimum Knee Angle is the knee angle of the recovery leg when the foot is nearest the buttocks during the recovery interval. Maximum Thigh Height is the maximum forward height reached by the thigh segment relative to the horizontal during the recovery interval. Leg Action is the drive interval plus a recovery interval. a) Drive Interval is the portion of leg action when the foot is in It consists of three contact with the supporting surface. phases. 1) Foot Strike Phase is the time from touchdown to when the foot is flat on the supporting surface and the joints of the support leg are undergoing flexion. 2) Midsupport Phase is the time from when the foot is completely in contact (flat) with the supporting surface until the heel breaks contact with the supporting surface. During this phase, the actions at the hip and knee joints reverse from flexion to extension and the movement at the ankle joint reverses from dorsiflexion to plantar flexion. Takeoff Phase is the time from when the heel breaks contact The hip and knee w 3 with the supporting surface to toe off. joints are undergoing extension and the ankle plantar I‘ll-"1'"1 “My 1 "mm For this flexion. b) Recovery lnterggl is the portion of leg action when the foot is not in contact with the supporting surface. It consists of three phases. 1) Follow Through Phase is the time from takeoff until the thigh reaches its maximum backward movement resulting in the hip joint being at its greatest angle of extension. 2) Forward Swing Phase is the time from when the thigh begins its forward movement until the thigh reaches its maximum height. 3) Foot Descent Phase is the time from when the thigh reaches its maximum height until foot touchdown. Arm Action is a forward phase plus a backward phase of arm movement. a) Forward Phase is the time from when the humerus begins its forward angular movement until it stops its forward angular movement. b) Backward Phase is the time from when the humerus begins its backward angular movement until it stops its backward angular movement. Linear Distance is the length (magnitude) of a straight line For this joining two positions, i.e. an initial and final position. study linear distance was measured in centimeters. Linear Displacement is the length (magnitude) and direction of a straight line joining two positions, i.e. an initial and final position. For this study linear displacement was measured in centimeters. nd: tile 5M reath “Gm ”598: Wane Linear Speed is the change in distance per unit of time of a body segment or the body's center of gravity. Speed is a scalar quantity which represents magnitude. For this study speed was measured in centimeters per second. Linear Velocity is the change in displacement per unit of time of a body segment or the body's center of gravity. Velocity is a vector quantity which represents both magnitude and direction. For this study velocity was measured in centimeters per second. Angular Distance is the magnitude of change in the angle between two positions, i.e. the initial and final positions, of a rotating body or body segment. For this study angular distance was measured in both radians and degrees. Angular Disglacement is the magnitude and direction of change in the angle between the initial and final positions of a rotating body or body segment. For this study angular displacement was measured in both radians and degrees. Angular Velocity is a change in angular displacement per unit of time. For this study angular velocity was measured in radians per second. Peak Angular Velocity is the position at which a body segment reaches its greatest angular velocity. Sequence of Peak Angular Velocity is the order in which the body segments reach their individual peak angular velocity about their respective joint. Movement in the Sagittal Plane refers to observation of the movement from a camera that is placed so that movement occurring in the sagittal plane can be recorded (side view). The sagittal camera is placed perpendicular to movement occurring in the sagittal plane (direction of movement). Movement in the Frontal Plane refers to observation of the movement from a camera that is placed so that action occurring in the frontal plane can be recorded (front view). The frontal camera is placed perpendicular to movement occurring in the frontal plane. Trunk Inclination Measurement is measurement of trunk lean from the horizontal to the line that passes from the top of the head to the point located half the distance between the hip joints. The measurement is made counterclockwise relative to the horizontal (see Figure 17, p. 86). Segmental Inclination is a method of measuring the angle of limb segments in biomechanics. A limb segment is measured counterclockwise relative to the horizontal from the distal end of the segment (see Figure 16, p. 85). Segmental inclinations are then used in interpreting changes in joint angles between body segments. Midline of the Body. The midline of the body is determined first by locating the midpoint between the two hip joints and the midpoint between the two shoulder joints, then connecting the two midpoints. Measurements were made by drawing a line from, and perpendicular to, the supporting surface up through the midpoint between the hip joints, and continuing to equal head height. The distance was measured in centimeters (see Figure 23, p.93). .,_,Yn,.-_,. The Research Hypotheses This study investigated the changes in selected kinematic variables for each of the four developmental stages of running (Seefeldt et al., 1972), with stage one being the least mature form and stage four being the most mature form. The study also identified trends in the selected kinematic variables between boys and girls performing in each of the four developmental stages. One complete running cycle (touchdown of one foot until the same foot touched down again) for each leg was used for analysis. Using a complete cycle for each leg enabled the observation of any differences between right and left limb action in the skill during the film trial selected for analysis. Kinematic Variables. From the sagittal plane (side view) film the following kinematic variables were studied: L The inclinations of the thigh, shank, and foot segments at specified points during one running cycle for each leg. a. Leg drive interval: touchdown and takeoff. b. Leg recovery interval: minimum knee angle and maximum thigh segment height. 2. The linear and angular displacement of thigh, shank, and foot segments between selected positions during one running cycle for each leg. a. Leg drive interval: touchdown to takeoff. b. Leg recovery interval: takeoff to minimum knee angle, minimum knee angle to maximum thigh segment height, and maximum thigh segment height to touchdown. Vir. stile The trunk inclination at touchdown and takeoff during the drive interval for each leg. The sequence of peak angular velocity for leg extension in the drive interval and for leg flexion in the recovery interval during one running cycle for each leg. The horizontal distance between the foot at touchdown and the downward vertical projection of the body's center of gravity for each leg (see Figure 22, p. 92). The temporal relationship of support and flight periods during one running cycle for each leg. The stride length and stride rate during one running cycle for each leg. The inclinations of the humerus and the forearm at maximum forward and maximum backward swing of the humerus. The linear and angular displacement for the humerus and the forearm between maximum forward swing and maximum backswing. From the frontal plane (front view) film the following kinematic variables were studied: 10. The positions of the centers of gravity of arm and leg segments in relation to the body's midline at selected points during one running cycle for each leg (see Figure 23, p. 93). a. Leg drive interval: touchdown and takeoff. b. Leg recovery interval: minimum knee angle and maximum thigh segment height. In addition the following relationships were investigated for each stage of running: 11. The relationship of stride length to stride rate, stride length to running speed, stride rate to running speed, trochanteric height to running speed, and trochanteric height to stride length. 12. The temporal occurrence between selected positions for each stage of running. a. Leg drive interval: touchdown to maximum leg extension and maximum leg extension to takeoff. b. Leg recovery interval: takeoff to minimum knee angle, minimum knee angle to maximum thigh segment height, and maximum thigh segment height to touchdown. Predicted Developmental Trends. Based on review of the qualitative films of running stages filmed at Michigan State University from 1967 through 1976, the following developmental trends were predicted for this study: L At touchdown, the inclination of the thigh, relative to the horizontal, will decrease from stage one to stage two, increase from stage two to stage three, and decrease from stage three to stage four. The inclination of the shank and foot, relative to the horizontal, will increase from stage one to stage two, then progressively decrease at stages three and four (see Figure l). 2. At takeoff, the inclination of the thigh and shank, relative to the horizontal, will decrease from stage one to stage two and from stage three to stage four, but will increase from stage two to stage three. The inclination of the foot, relative to the horizontal, will progressively decrease from stage one through Stage 1 Stage 2 Stage 3 Stage 4 Figure l. Illustrations of predicted changes in segmental inclinations of the leg at touchdown position. three, then increase from stage three to stage four (see Figure 2). At minimum knee angle of the recovery interval, the segmental inclinations of the thigh and shank relative to the horizontal will decrease from stage one through three, then increase from stage three to stage four (see Figure 3). At maximum thigh segment height, the segmental inclination of the thigh, relative to the horizontal, will decrease from stage one through stage three, then increase from stage three to stage four (see Figure 4). The angle of trunk inclination will increase as the stages progress from one to four. The sequence for peak angular velocity of leg extension during the drive interval and of leg flexion during the recovery interval will move from simultaneous occurrence, or non sequential, to sequential occurrence as the stage level increases. The leg extension sequence for the drive interval will follow the order: thigh, shank, and foot, while the leg flexion sequence during the recovery interval will follow the order: shank, thigh, and foot. The horizontal distance between the foot at touchdown position and the downward vertical projection of the body's center of gravity during a running cycle for each leg will decrease as stages increase. During one running cycle for each leg, the time in support will decrease while the time in flight will increase at each successive stage. The stride length and rate, relative to leg length, will increase three, then increase from stage three to stage four (see Figure 2). At minimum knee angle of the recovery interval, the segmental inclinations of the thigh and shank relative to the horizontal will decrease from stage one through three, then increase from stage three to stage four (see Figure 3). At maximum thigh segment height, the segmental inclination of the thigh, relative to the horizontal, will decrease from stage one through stage three, then increase from stage three to stage four (see Figure 4). The angle of trunk inclination will increase as the stages progress from one to four. The sequence for peak angular velocity of leg extension during the drive interval and of leg flexion during the recovery interval will move from simultaneous occurrence, or non sequential, to sequential occurrence as the stage level increases. The leg extension sequence for the drive interval will follow the order: thigh, shank, and foot, while the leg flexion sequence during the recovery interval will follow the order: shank, thigh, and foot. The horizontal distance between the foot at touchdown position and the downward vertical projection of the body's center of gravity during a running cycle for each leg will decrease as stages increase. During one running cycle for each leg, the time in support will decrease while the time in flight will increase at each successive stage. The stride length and rate, relative to leg length, will increase Stage 1 Stage 2 Stage 3 Stage 4 Figure 2. Illustrations of predicted changes in segmental inclinations of the leg at takeoff position. 20 i Stage 1 Stage 2 Stage 3 Stage 4 Figure 3. Illustrations of predicted changes in segmental inclinations of the leg at minimum knee angle during the recovery interval. L-i— F1 in it. 21 Stage 1 Stage 2 Stage 3 Stage 4 Figure 4. Illustrations of predicted changes in segmental inclinations of the thigh at maximum thigh segment height. 21 Stage 1 Stage 2 Stage 3 Stage 4 Figure 4. Illustrations of predicted changes in segmentall inclinations of the thigh at maximum thigh segment height. ... at each successive stage. At maximum forward arm swing, the segmental inclination of the humerus, relative to the horizontal, will decrease from stage one to stage two, and from stage two to stage three, but will increase from stage three to stage four. The inclination of the forearm, relative to the horizontal, will decrease from stage one through stage three, then increase from stage three to stage four (see Figure 5). At maximum backward arm swing, the segmental inclination of the humerus, relative to the horizontal, will decrease from stage one to stage two, increase from stage two to stage three, then decrease from stage three to stage four. The segmental inclination of the forearm relative to the horizontal, will decrease at each successive stage (see Figure 6). The distance between the center of gravity of each limb segment relative to the body’s midline will decrease at each successive stage. bygothgsgg, The following hypotheses were examined for this study: Each of the selected kinematic variables will follow the predicted trends, showing significant differences from stage to stage, in the running behavior of young children. There will be no observed differences on each of the selected kinematic variables across stages between boys and girls. -__; mt Stage 4 Stage 2 Stage 3 Stage 1 O ' of arm rotation ' d angular m forwar at max1mu nd forearm 0f the humerus a swing. 24 Stage 1 Stage 2 Stage 3 Stage 4 Figure 6. Illustrations of predicted changes in segmental inclinations of the humerus and forearm at maximum backward angular rotation of arm swing. MN The Scope of the Study The study examined the running gait of preschool aged boys and girls. Each subject was filmed simultaneously by two cameras positioned orthogonally to each other; one camera from the sagittal (side) view, the other from the frontal (front) view. One boy and one girl demonstrating each one of the four classic developmental stages of running (n=8) were selected from an identified potential subject pool of children participating in the Michigan State University Early Childhood Motor Skill Development Program. Additional subjects were selected as needed (i.e. to represent immature stages not demonstrated by subjects in the Early Childhood Program) from siblings of the participants in this program or from other available children. Each subject participated in a single filming session. Selected anthropometric measurements also were taken during this session. Selected film trials were digitized and processed through a biomechanical software program to obtain the necessary linear and angular displacements, velocities, and accelerations for statistical analyses in order to answer the posed research hypotheses. Limitations The following limitations were identified for this study: 1. Motor development research studies have traditionally used large numbers of subjects, where biomechanical research studies have traditionally used a small number of subjects. For this study eight 26 subjects were selected, one boy and one girl for each developmental stage of running. The developmental stages for running as determined by Seefeldt et al. (1972) were ascertained through qualitative film analysis of over 150 children between the ages of 18 months and 8 years of age. These four developmental stages of running have been verified on four occasions (Branta et al., 1984; Branta et al., 1985; Early Childhood, 1985; Fountain et al. 1981). The latest validation (Early Childhood, 1985) involved over 1500 children ages 2.5- to 5.0-years of age. This particular skill stage sequence has been well documented, and no qualitative differences have been noted between boys and girls performing at the various stages. There is general agreement among motor development specialists that developmental stages are age related, but not age dependent, and that boys and girls demonstrate the same degree of identifiable characteristics as they progress through the developmental stages. Thus, the small number of subjects was deemed acceptable for this study. The subjects selected for the study were from an available population of children most of whom were enrolled in a program emphasizing fundamental motor skill development for preschool age children. Program enrollees were from the greater Lansing, Michigan area. Subject selection was further limited in that only children demonstrating the best representative form of a stage during the 1985 fall testing and nearest the modal age for stage, as determined by Early Childhood (1985), were considered for inclusion in the study. - The study was limited by the common difficulties encountered in 27 cinematographic research. These difficulties include error in locating anatomical landmarks when digitizing due to hidden segments and perspective error resulting from body segments positioned at different distances from the cameras. Assumptions The study was completed based on two assumptions: 1. That the subjects filmed were representative of normal preschool age boys and girls. 2. That the subjects were developing normally and free from any previous or present handicapping conditions. Chapter II Review of Literature The study of motor development entails identification of changes in motor behavior that are reflective of an interaction of the human organism with its environment. Identified changes in motor behavior have been classified based on stage theories originating in biology and developmental psychology. To achieve the most effective comprehension of the development of a fundamental motor skill, the investigator needs to: (a) understand developmental stage theory, (b) review completed research on the specific skill of interest, and (c) inquire into other disciplines for related investigations and research techniques that may help advance the interpretation of the skill’s development. The investigator who is concerned with the development of a fundamental motor skill also must have a thorough understanding of the mature form of the specific skill being studied. This provides the necessary background against which the developmental progress in the skill can be evaluated (L. E. Halverson, 1966). The following review of literature reflects the interdisciplinary approach taken by this study. Attention will be given to: (a) the origins of developmental stage theory and its application to motor development; (b) the early studies in motor deve10pment; (c) the 28 developmental studies of fundamental motor skills; (d) the development of running as studied by specialists in motor development and developmental biomechanics; and (e) the kinematic analysis of mature running form. Developmental Stage Theory Developmental staging theory has provided a method of identifying and grouping characteristics or events along a continuum. The following section traces the origins of developmental stage theory and its adaptation to the study of motor skill development. Biological - Psychological Origins. The emergence of developmental psychology early in the Twentieth Century was the result of increased interest in children and concurrent advances in the scientific method of study. Psychologists began to search for the best ways to educate children (how do they learn?) and to investigate the biological development of the human organism (how do they grow?). The model of developmental used by psychology comes basically from biological sciences (Gardner, 1982). Within the biological discipline, scientists have charted daily progress, identified stages of development, used substances which may control development, and established an overall theoretical framework of an organism's development. This developmental model used by biology views development as making continual differentiation (simple to complex) and integration (a coming together of isolated parts to form a more complex organization) (Gardner, 1982). The biological model of development and related terminology has been borrowed by many other disciplines, including psychology. It has been applied to the physical development of children with little difficulty. But in the more intangible areas such as cognitive, emotional, and moral growth, the application of biological terminology has been criticized for being too vague, too ambitious, or too restrictive (Gardner, 1982). Questions concerning qualitative versus quantitative developmental descriptions also are raised when attempting to apply biological terminology to these areas. A major problem lies in the disagreement as to the meaning and use of the term “stages". Brainerd (1978) describes three general applications of the term. First, stages have been used as aesthetic or ideals that do not necessarily refer to any definite or measurable elements in development. Here the term ‘stage' is used as a method of eliciting certain images (such as Erickson’s (1963) theory of psychosexual development). Second, stages have been used as descriptions of precise and measurable aspects of behavioral development, that is, arbitrarily defined characteristics known to change with age. He notes in the descriptive use of stages that degrees of abstractness may be represented from concrete, detailed descriptions to the isolation of commonalities and patterns present in diverse classes of behavior. Third, stages have been used in an explanatory capacity and must satisfy three criteria to be legitimate explanations of development: (a) the stages must be descriptive of the behaviors that undergo change; (b) they must postulate antecedent variables believed to be responsible for the changes; and (c) there must be ways to measure The biological model of development and related terminology has been borrowed by many other disciplines, including psychology. It has been applied to the physical development of children with little difficulty. But in the more intangible areas such as cognitive, emotional, and moral growth, the application of biological terminology has been criticized for being too vague, too ambitious, or too restrictive (Gardner, 1982). Questions concerning qualitative versus quantitative developmental descriptions also are raised when attempting to apply biological terminology to these areas. A major problem lies in the disagreement as to the meaning and use of the term "stages“. Brainerd (1978) describes three general applications of the term. First, stages have been used as aesthetic or ideals that do not necessarily refer to any definite or measurable elements in development. Here the term ‘stage' is used as a method of eliciting certain images (such as Erickson’s (1963) theory of psychosexual development). Second, stages have been used as descriptions of precise and measurable aspects of behavioral development, that is, arbitrarily defined characteristics known to change with age. He notes in the descriptive use of stages that degrees of abstractness may be represented from concrete, detailed descriptions to the isolation of commonalities and patterns present in diverse classes of behavior. Third, stages have been used in an explanatory capacity and must satisfy three criteria to be legitimate explanations of development: (a) the stages must be descriptive of the behaviors that undergo change; (b) they must postulate antecedent variables believed to be responsible for the changes; and (c) there must be ways to measure the antecedent variables independently of the behavioral changes. Although not without criticism, Jean Piaget‘s stages of cognition (1983), Lawrence Kohlberg's stages of moral development (1963), Sigmund Freud’s stages of sexual development (1930/1964), and Erik Erikson's stages of life (1963) may be considered classic examples of stage theories. Piaget's criteria for stages (hierarchization, structural wholeness, integration, consolidation, and equilibration) have been most widely accepted and used in developmental psychology. Hierarchization refers to a fixed order of succession of the different levels that compose a developmental sequence. That is, the order of the appearance of the levels remains the same. There can be no variation in the described order. Individuals may progress through the sequence at slightly different rates, but the order of succession remains the same. Structural wholeness refers to the individual operating on the same level in several related areas. Integration refers to the accomplishments of a higher stage incorporating those of the lower stage(s). Integration involves the transformation of lower stage elements by restructuring them to form new elements as well as coordinating lower stage elements with completely new elements. Consolidation refers to the continuous gradual evolution of one stage from a previous stage. For a period of time, i.e. during the transition, elements of both stages will be evident. Piaget refers to this as horizontal decalage. And finally, equilibration refers to the process through which the individual develops. Development consists of a series of periods of equilibration followed by disequilibration as an individual moves from a state of stability operating at one stage to a state of instability as the transition occurs to a higher stage. Gesell (1939) used the term reciprocal interweaving to describe the last two characteristics relating the whole process as an ascending spiral of gradual change under the influence of both biological (genetic) and environmental factors. Essentially, developmental psychologists have strictly adhered to the requirement that all five criteria be met for proposed stage theories to be accepted as an explanation for development. However, this rigid thinking has come under criticism. Brainerd (1978) questions the explanatory value of Piaget's stages of cognitive development. He believes that they are descriptive rather than explanatory in nature since the antecedent variables leading to behavioral changes cannot be measured separately. The concepts of invariant or irreversible sequencing has been questioned by Holstein (1976) and Kurtines and Breif (1974) in reviewing the work of Kohlberg’s (1963) development of moral thought. Kurtines and Greif (1974) also question the qualitative differences in the hierarchical stages proposed by Kohlberg. In response to criticisms about the limitations of the definitions of stage criteria, Piaget (1960) himself replied that the five criteria are in reality degrees of the possible structuraliz7tion of stages. The five criteria presented represent what Piaget found in the field (versus the laboratory) setting where "stages" are most evident. In reality, whether or not all five criteria are used in a developmental stage theory is up to the individual proposing the theory. Therefore the usefulness of stages can be generalized to a variety of fields. Stage Theory Applied to Motor Development. Stage theory in developmental psychology gave rise to the use of stage theory in motor skill development. This is logical since many of the early developmental psychology studies used motor skills to demonstrate the existence of sequences in development (Ames, 1937; Burnside, 1927; Gesell, 1946; McGraw, 1943; Shirley, 1931). However, the use of the term “stage“ in motor development has been confusing. Without the theoretical background the term stage could be interchanged with descriptions such as “type", "phase“, “pattern“, or "steps“ to describe how a child might react in certain environmental situations or to describe a series of differentiated qualities which appear in a .predictable sequence. Motor stages have been identified through extensive observation, both direct and cinematographic. In a descriptive sense, the focus of early motor development studies varied considerably, yet all were interested in the mechanisms, form and function of movement. For example, H. M. Halverson (1931) focused on what changes occurred; Shirley (1931) concentrated on the order of the changes that occurred; McCaskill and Wellman (1938) attended to the identification, ordering, and quantification of tasks; and Godfrey and Kephart (1969) prepared a check list for elements of a mature performance. In more recent work, investigators have concentrated on the qualitative changes in form that occur during motor skill development (Roberton, 1975, 1982; Roberton & L. E. Halverson, 1984a, 1984b; Seefeldt et al. 1972; Seefeldt & Haubenstricker, 1982). In a theoretical sense, stage theory refers to the presumptive ‘1‘ 34 structures underlying movement. That is, the underlying neural development directing the changes observed in motor development (Roberton, 1977, 1978). And, according to Wohlwill (1973), the strength of developmental stages comes from their power to demonstrate that each step evolved from the preceding one. The use of stage theory in this Piagetian context is evident in some of the studies previously mentioned (Ames, 1937; Gesell, 1946; McGraw, 1943; and Seefeldt et al., 1972). Another point of possible confusion in the use of ‘stages’ in motor development occurs with the concepts of intraskill and interskill development. Interskill stage sequencing involves the developmental ordering of several related tasks. Shirley's (1931) stages of locomotion are an example of interskill staging. Such stages have been related to age ordering. lntraskill staging involves the development of a single skill. The work of H. M. Halverson (1931), Roberton (1975), Roberton & L. E. Halverson (1984a, 1984b), Seefeldt et al. (1972), Seefeldt & Haubenstricker (1982), and Wild (1938) are examples of intraskill staging. Early Studies of Motor Development Interest and research in the motor development of children date back several decades. Child psychologists were responsible for much of this early research as they attended to the normal mental and physical development of children. Gesell (1929, 1948) charted normal ontogenic behavior from birth to age 10. Shirley (1931) observed 25 babies through the first 2 years of their lives. Bayley (1935) followed the 34 structures underlying movement. That is, the underlying neural development directing the changes observed in motor development (Roberton, 1977, 1978). And, according to Nohlwill (1973), the strength of developmental stages comes from their power to demonstrate that each step evolved from the preceding one. The use of stage theory in this Piagetian context is evident in some of the studies previously mentioned (Ames, 1937; Gesell, 1946; McGraw, 1943; and Seefeldt et al., 1972). Another point of possible confusion in the use of ‘stages’ in motor development occurs with the concepts of intraskill and interskill development. Interskill stage sequencing involves the developmental ordering of several related tasks. Shirley's (1931) stages of locomotion are an example of interskill staging. Such stages have been related to age ordering. Intraskill staging involves the development of a single skill. The work of H. M. Halverson (1931), Roberton (1975), Roberton & L. E. Halverson (1984a, 1984b), Seefeldt et al. (1972), Seefeldt & Haubenstricker (1982), and Wild (1938) are examples of intraskill staging. Early Studies of Motor Development Interest and research in the motor development of children date back several decades. Child psychologists were responsible for much of this early research as they attended to the normal mental and physical development of children. Gesell (1929, 1948) charted normal ontogenic behavior from birth to age 10. Shirley (1931) observed 25 babies through the first 2 years of their lives. Bayley (1935) followed the 35 development of over 40 infants from the age of one month to 36 months. McGraw (1935) investigated selected behavior patterns in growing infants through a detailed 2-year study of fraternal twins. In general, these early studies yielded extensive information on the development of upright locomotion revealing that the process was very orderly, yet highly individualized. During this same time period another group of investigators began examining motor skill achievement separate from mental development. Cunningham (1927) tested the motor achievements of approximately 100 children ranging in age from 12 to 42 months. Children were tested on their birthday and 6 months thereafter in an attempt to establish performance norms for test items of gross motor coordination. Jenkins (1930) tested three hundred 5-, 6-, and 7-year olds to establish standards of performance on nine different motor tasks. Time, distance, and accuracy measurements were gathered. McCaskill and Hellman (1938) studied motor skills in preschool age children (2 to 6 years) to determine the developmental stage, sequence of development, interrela- tionships among skills, and gender differences in scores. Scores were assigned according to the difficulty of execution based on the percentage of children who accomplished the tasks. In a combination survey of 1,973 children and a one year follow up study of 9 children, Guttridge (1939) examined the motor skill achievements of young children betwaen the ages of 2 and 7 years. Achievements were based on performance scores, teacher ratings, and observation reports. These multiple skill studies investigated what were considered the common activities of children within the age range of 1 to 7 years. Quantitative measures (time, distance, and accuracy scores) were gathered on skills such as running, hopping, skipping, jumping, throwing, catching, kicking, and ball bouncing. Although achievements, in general, were based on performance product scores, McCaskill and Hellman (1938) noted differences in skill development, sequence of individual skill development, order of appearance of skills, and performance variability within any one age group. With few exceptions, significant gains were found as age increased, but McCaskill and Wellman (1938) indicated very little differences between the two oldest groups in their study (5- and 6-year— olds). Up to 1940, only Wild (1938) centered complete attention on the actual development of a single fundamental motor skill in order to identify age characteristics for that skill. All studies made comparisons of age/grade and gender. For most of the next two and a half decades further investigations into motor skill achievement and development of young children were noticeably absent from the research literature. The few studies that were conducted generally dealt with the development of measurement scales for skill performance of elementary school children (Carpenter, 1942; Johnson, 1962; Latchaw, 1952) or compared physical growth/ biological maturity with performance proficiency in certain gross motor activities (Seils, 1951). Glassaw and Kruse (1960) observed motor skill achievement in girls ages 6 to 14 years on the standing broad jump (distance), the 30-yard run (speed), and throwing ability (velocity). Trends were noted on the basis of performance scores and demonstrated that children tend to remain in the same relative position within a groUp throughout the elementary school years. Glassow, L. E. Halverson, and Rarick (1965) reported the results of a 6*year study of children in grades 1 through 6. This 1965 study was unique in that it investigated skill development in terms of performance scores, quality of skill coordination, physical fitness, and strength measures in both a traditional and a vigorous activity type physical education program. This was one of the first research attempts to link the quality of a skill (form) with the resulting performance scores. Improvements with age were noted on both the qualitative and quantitative measurements of the skills under investigation. The work by Deach (1951) was the first study since Wild's (1938) to focus completely on skill pattern development. Deach investigated the development of discrete performance patterns in children 2— through 6- years of age for selected skills (throwing, catching, kicking, striking, and ball bouncing). This investigator examined the course of development in terms of mature adult performances in the selected skills. Deach's investigation was limited to a small cross-sectional study, but the results indicated development progressing from simple arm and leg actions to integrated total body coordinations. From the late 1950's through the early 1970's, interest in motor skill development research began to expand. Physical educators specializing in biomechanics were examining kinematic and kinetic differences in developing skills. These studies analyzed skills either by age/grade and gender levels (Brown, 1978; Clause, 1959; Fortney, 1964, 1980; Mersereau, 1974, 1977; Smith, 1977) or by “good“ and "poor" skill levels on the basis of a performance measurement (Beck, 1966; Dittmer, 1962). During this same time period, physical educators specializing in motor development made use of cinematography to collect extensive data for descriptive studies of skill development. Examples of research using these film sources include the studies on jumping by Hellebrandt, Rarick, Glassow, and Carns (1960), throwing by Roberton (1975), fundamental motor skills by Seefeldt et al. (1972), and galloping by Sapp (1980). These film studies also produced two methods of staging motor skill development. One method, the component parts method, investigated sequential development of body parts separately (i.e. legs, pelvis, trunk, arms) for various fundamental motor skills (Roberton, 1975; Roberton & L. E. Halverson, 1984a, 1984b). The other method, the total body configuration method, identified distinguishing characteristics of a composite performance so that they were easily observed by visual inspection (Seefeldt et al. 1972; Seefeldt & Haubenstricker, 1982). This latter approach was later adopted by McGlenaghan and Gallahue (1978) and Stewart (1980). These studies will be discussed in more detail in the remaining portions of this chapter. Studies of Developmental Stages in Fundamental Motor Skills Early studies in child development demonstrated that children follow a predictable sequence in obtaining proficiency in motor skills (Gesell, 1929; McGraw, 1935). The process of determining stages in fundamental motor skills serves as a means of synthesizing and simplifying the complexities of underlying neurophysiological processes and the resulting movements that change over time. Such identification 1‘—‘ CA ~13 of specific pattern changes in the phases of aideveloping motor skill provides the researcher and teacher with a basis for comparing a child's progress in acquiring mature motor patterns as well as for planning instructional strategies for learning and remediating motor skills;; Currently two schools of thought have emerged in the staging of fundamental motor skills: component part staging (Roberton, 1975, 1976, 1977, 1984); and total body configuration staging (Seefeldt et al., 1972; Seefeldt & Haubenstricker, 1982). The component part approach to staging fundamental motor skill development, when first proposed by Roberton (1976), attempted to adhere to the Piagetian criteria for staging, particularly Piaget’s criteria for universal and invariant sequences. Roberton noted in her original work that mature performance of various parts of the body seemed to develop at different rates. Developmental stages were then proposed for various parts of the body (arm, trunk, pelvis, legs) as a skill was performed. The sequences were accepted only if all subjects demonstrated the stages in the proposed order. Any variation could only be to adjacent stages. Roberton (1982) has since given consideration to an alternative stage model, a population or probability stage model. This new model for developmental stages, while preserving the ordered regularity of spatio—temporal transformations that occur in motor skill development, permits greater flexibility than the classic Piagetian model. The total body configuration approach to staging fundamental motor skills defines stages based on observation to determine a comprehensive series of movements exhibited to accomplish a specific task (Seefeldt et al., 1972). Work on the total body configuration approach to staging 40 fundamental motor skills began in the late 1960's. FThrough extensive qualitative film analyses and by viewing movement as a biomechanical phenomenon, joint actions were identified, ordered, and classified to determine the complete movement series used by children to accomplish certain taskstijtages were defined when a series of movements demonstrated sufficient commonality as a general phenomenon during children's skill performance. An abrupt change in the positioning of one or more body segments or limbs in relation to previous position depicted the transference from one stage to a higher stage. The change from one stage to a higher level stage resulted in more proficient performance of the task by allowing for a single or combination of mechanical improvements to occur: (a) creating an improved positioning of the body for greater force production; (b) allowing a more extensive range of movement around force producing joints; (c) increasing the number of joints involved in the power train; and (d) permitting less interruption and greater flow to the total movement (Seefeldt & Haubenstricker, 1982)LJ Recognizing that not all the parts of a skill mature at the same rate, there is sufficient identity among the various elements of the skill so that a total configuration description becomes a practical method of describing a task's development. This approach to the staging of fundamental motor skills accepts omissions and reversals as a reality that does not invalidate the stage sequence. The utility of the stage sequence lies in its ability to predict movement characteristics in the majority of the performers, accepting that a child who deviates from the sequence will not cause the invalidation of the sequence. (The developmental stages proposed by Seefeldt et ath 41 (1972) and subsequent staging research conducted at Michigan State University have been further studied and verified by Branta et al. (1984), Branta et al. (1985), Early Childhood (1985), Fountain et al. (1981), Haubenstricker, Branta, & Seefeldt (1983), Haubenstricker & Seefeldt (1977), Haubenstricker, Seefeldt, & Branta (1983), Haubenstricker et al. (1981), Lerner (1975), S. Miller et al. (1977), and Way et al. (1979). The Development of Runninggform Running is a vigorous form of locomotion, is an outgrowth of walking, and is characterized by distinguishable alternating periods of flight and single foot support. Initial running patterns may actually occur prior to nonsupported walking in response to maintaining balance while trying to move (Broer, 1973). Figure 7 illustrates the extreme high guard arm position and short, choppy steps, of early attempts at running.I/The first intentional attempts at running usually appear around 18 months of age and represent a modified walk since a flight period is not truly evident. By about 2 years of age, children have gained enough balance and body control to exhibit a truer form of running (Espenshade & Eckert, 1980). As development continues, the width of the stance narrows, there is less toeing out, and the rhythm of the run becomes smoother. By the time children enter kindergarten, they have developed reasonably good running skill and understand what it means to run as fast as possible (Wickstrom, 1983);1 Research by Seefeldt & Haubenstricker (1982) and Early Childhood (1985) support “cos .uowcma .~+mm:cu m agony“: mamum xnaozu .ucozm ucm mecm may +0 cowufimoa ucmsm ; a; memcuxm xn umuwcmuumcmcu mcuccsc um unemuum HmfiuMCH .m mcsmau 2 4 (foe/4.. «u. «.../4.. is as? $3 a at. (I later in this chapter.) Since the late 1950's, research efforts on the development of fundamental motor skills have focused on the qualitative changes that parallel the quantitative trends. A review of the literature revealed 22 studies that either dealt directly with, or included, the development of running in children. These studies are summarized in Table 1. Fourteen of the 21 studies can be generally categorized as what Roberton (1972), Small (1982), and Wickstrom (1975) have referred to as developmental kinesiology investigations. The more current term is developmental biomechanics (Garrett, 1979). The biomechanical investigations assessed differences in kinematic and kinetic variables between children of differing age and gender groups. The sequence of appearance of developmental stages of running was investigated in 8 of the 21 studies. Children within the age ranges of 18 months to 8 years were investigated in 15 of the 21 studies. Subjects within the age range of 5 to 11 years were investigated in six of the 21 studies. One study investigated 3- to 10-year olds and one study investigated children aged 14 to 67 months. Eight of the 21 studies involved cross- sectional investigations, while 14 of the 21 studies involved longitudinal and mixed longitudinal research spanning from 4 months to 8 years. Data on performance differences between boys and girls in the development of running skill are sparse. Only 12 of the 21 studies reviewed involve comparison of boys and girls performances. Glassow et d1. (1965) and Amano et al. (1983) reported no difference in running between boys and girls. Atwater et al. (1981) stated that few gender later in this chapter.) Since the late 1950's, research efforts on the development of fundamental motor skills have focused on the qualitative changes that parallel the quantitative trends. A review of the literature revealed 22 studies that either dealt directly with, or included, the development of running in children. These studies are summarized in Table l. Fourteen of the 21 studies can be generally categorized as what Roberton (1972), Small (1982), and Wickstrom (1975) have referred to as developmental kinesiology investigations. The more current term is developmental biomechanics (Garrett, 1979). The biomechanical investigations assessed differences in kinematic and kinetic variables between children of differing age and gender groups. The sequence of appearance of developmental stages of running was investigated in 8 of the 21 studies. Children within the age ranges of 18 months to 8 years were investigated in 15 of the 21 studies. Subjects within the age range of 5 to 11 years were investigated in six of the 21 studies. One study investigated 3- to 10-year olds and one study investigated children aged 14 to 67 months. Eight of the 21 studies involved cross— sectional investigations, while 14 of the 21 studies involved longitudinal and mixed longitudinal research spanning from 4 months to 8 years. Data on performance differences between boys and girls in the development of running skill are sparse. Only 12 of the 21 studies reviewed involve comparison of boys and girls performances. Glassow et al. (1965) and Amano et al. (1983) reported no difference in running between boys and girls. Atwater et al. (1981) stated that few gender 44 Table 1 Summary of Studies on the Development of Running in Children. WS If STUDY (fixed RESEAQGEHS) Kineaatic Kinetic Stage Gender Age Grade Cross- Longi- Longi- (yrs) sectional tudinal tudinal Adana, Hizutani, 1: Hoshikawa, 1983 X H 4-7 4 yrs. Atwater, Harris, Willials, & Wilacre, 1981 X H H: X Beck, 1966 X ('1 1,3,5 2 yrs. 2,4,6 Eranta, Haubenstricker, Kiger, t Ulrich, 1984 X H 2.5-5.0 3 yrs. Branta, Kiger, l Yager, 1985 X H 2.5-5.0 3 yrs. Bram, 1978 X‘ F P,K,2,5 X Clause, 1959 X )1 1.2-4.9 8 mos. Dittmer, 1962 X F 6.0-1() 5 yrs. Early Childhood, 1985 X" H 2.5-5.0 8 yrs Fortney, 1964 X H 2-6 4 yrs Fortney, 1980 X X H 2,4,6 X Fountain, Ulrich, Seefeldt, f1 Haubenstricker, 1981 X" H-F 2.5—5.0 3 yrs, Glassow, LE. Halverson, t Rarick, 1965 Xh M-F 1,3,5 2 yrs. Learner, 1975 X” H—F 3.0-5.0 X Hersereau, 1974 X X F 1.9-2.08 4 nos. Herse'eau, 1977 X” F 2.5-5.5 X S. Miller, Haubenstricker, & Seefeldt, 1977 X" H 2.5—5.0 1 yr Miyaaaru, 1976 X h 2.0-6.0 X Seefeldt, Reuschlein, t Vogel, 1972 X" H 1.5-8.9 x Smith, 1977 X H 5.0—12 5.5-“ yrs. Vilchkovsky, Dreshcuk, l: Shpitalny, 1973 X H 3.0-7.0 X Hay, Haubenstricker, l: Seefeldt, 1979 X“ h-F 6.0-8.9 X a = Also included Fourier analysis. 11 = Other fundamental motor skills also tested 45 differences emerged among 3- to 6—year—olds studied with velocity significantly related to height and leg length for the youngest girls. Vilchkovsky et al. (1973) reported only that boys performed better than girls at all ages on running speed. Fortney (1980) noted significant gender differences in four kinematic variables: (a) the joint angle of the swing hip (at touchdown, midsupport, and takeoff), (b) peak angular velocity of flexion of the swing hip, (c) the joint angle of the swing knee, and (d) the range of motion of the swing hip. In the studies investigating the developmental stages of running in children, boys and girls progress through the running stages in the same order, but at each age level reported, the boys in general used a more mature running stage than the girls (Branta et al. 1984; Branta et al. 1985; Early Childhood, 1985; Fountain et al. 1981; Learner, 1975; S. Miller et al. 1977; Way et al. 1979). Developmental Stages of RunningJ Developmental stages for running were first proposed by Seefeldt et al. (1972). Subsquently, McGlenaghan and Gallahue (1978) proposed a three-stage sequence of running based on the fundamental sequence proposed by Seefeldt et al. (1972). Drawing upon the earlier investigations of Seefeldt et al. (1972) and Wickstrom (1983), Roberton and L. E. Halverson (1984) hypothesized a developmental sequence of running that involves three steps for the leg action and four steps for the arm action components. The sequence of developmental stages for running proposed by Seefeldt et al. (1972) has been verified through cross-sectional and mixed longitudinal studies (Branta et al., 1984; Branta et al., 1985; 46 Early Childhood, 1985; Fountain et al., 1981; Learner, 1975; S. Miller et al., 1977; Way et al., 1979). The four stages of running are illustrated in Figures 8 through 11. rIn the skill of running the children use more mature running patterns as they increase in age, with boys generally using a more mature pattern at each age level. Seefeldt and Haubenstricker (1982) reported that mature (stage 4) running form was demonstrated by 602 of the boys at age 4 and by 601 of the girls at age 5.5 yearsll A mixed longitudinal study of the motor skill development in young children ages 2.5 to 5.0 years was begun at Michigan State University in 1978. Data from this study have been analyzed on four occasions over the past 8 years (Branta et al., 1984; Branta et al., 1985; Early Childhood, 1985; and Fountain et al., 1981). Figure 12 illustrates the appearance of the stages as indicated in the analyses completed by Fountain et al. (1981) and Early Childhood (1985). The latest analysis (Early Childhood, 1985) of these data has provided performance standards for each stage by age and gender, mean 30-yard run times and speeds, percentile ranks for running performance by stage, age, and gender, percentile ranks for 30-yard run time by age and gender, and mean run times and speeds by stage, age, and gender. Tables for these data are located in Appendix A. The data show that at age 4 over 50% of the boys are using a mature running form (stage 4) and at age 5 over 502 of the girls were using a mature running form. Mean 30-yard run times and speeds show a decrease in time and increase in speed with progression in stage level and age for both boys and girls. . swam $0 mewumcv .memL$ EHH+ mumUwucfl mcmnesz csc mco m . ewa ucm Awnmfi .Hmmo> a .cfimfizumsmm caufimwmmmv cofluuwcummo dlmumdwm awe: :m om mua+csm we“ came Camemc ummw map .cmmm m“ coflxmfi+ mmcx aflowfib .sfimsomcmquewm .uoo+ mcflycm mcu cufiz mums m“ aumucou nonwcsm use .cyuflz cmudsozm we ucm .ucozm mg muscum one .Acofiuflmou ucmsouzmfizv “coca; cwuflzocm “m ucmzwufim umucmyxm mcm mecm we» .H mumym 47 H m HH ma .memc+ eHw+ mmewucH mcmnesz .csc 03y momom efifl+ ucm Ammo“ ,fimmo> a .cflmqumjmm .uufimwmmmv cowuaflcumma .coficmpmonucoflcmocm mmeoumn momH may +0 acmem>oe any new umxmfi+ ma mmfl mafizm was .mmmzu mcflcflmcummc mg» C“ umuoc mg cowxmfi+ mmcx cmymmcm .>Hmjomcmofinefim mum+csm ms» mcflxflcum «00+ acmucm we“ nus: >~Hmsms ms yumycoo .mcafi Hmwuflommufie may mmzumOLQQm ucm cmmcofi ms muscum we“ .aoessme “mamas .ucasa masses. as umcccau ace ace ... Hwy-ms nmrdnwdfiw we. a w a mm cm Hm mm s; +0 ocfluacp .o mcsmmm .memc* EHw+ mumuwucfi mcmnssz .csc mmccu mowpm +0 mewumcp E: E; at; :32. a .5353; $2332 5:35me .2 Emad .mmmcmmu om mm ummcm mm.mn >me coaxmfi+ mmfi mcfizm mck .mcflfl Hmpaflummuufie m mcofim m>oe yom+ cyan ucm mmmmmLUCa Lumcmfl muflcum .=mooafimmc= ms uumucou “00+ wee .cofiyum >cmuoc (cmquOU m megmmm ucm xmfi+ >me new Hm>mH “mam: zofimn umwccmu mcm mecq .mucmflmn c0+ >Hflcmeflcq nmm: Lumen“ ac mcm macm mch .m mmmum 49 .memc+ eflw+ mumuflucfl mcmnesz .csc cso+ mompm we ocuumcu eflcw ucm .and .flmoo> a .cflmflzumswm .unfimwmmmv comuawcummo .2“ mcsmfid .mmmca >cm>0umc my“ mcficzu mxuouusn we“ so“: uumycou c“ >~cmmc m“ a“ Huge: xmfls >me mmH mcfizm use .mmmcu ucoaqsm mzu newczn esucmeoe use cfimucame my cum: ma conmH+ mmcx .cowuum omfi up cofiuflmoauo oumcsu cw ma cowyum Ec¢ .mcwccsc “ewcam mcflcsu zucm Hmmcmumume mg“ :0 >~mcwycm an >me “an mmwgwuofim> “mates co onm am mauuflmm; mu pumucou “and .a momum om. HN 0A ofi o m A sea a .Ammosv susym “cmeqofim>wo mfifisim c0002 noozuqccu chmm 0cm Afimafiv cmsuflcumcmnsmx a .ou~m+0mm .cuficfin .Cmecsod .cmucmo *0 pcmucmumucfl .cmcufiscu mum floozummca :0 occccsc +0 mummum Hmucmeaofim>mu 020 +0 mucmcmmaaq .malmumdwm u m9 m _uz mo_ _m_ new mmm N¢m mow c m wwmuz mm mm _m_ N.m_ v9 ¢m_ 6 _mm_ Qm 3 ca mm on mm 333 mo< [lulll _ _ _ )0! A O _ mofim # N 005m T); :1 12 1 .d 3 ud 1.0N no 3 N 4 1 non O 4/ «J m mwu mcflccnc m +0 mycmcou50u mcu we >Lmeezm .mH mesmfiu was 2:222 2s; 3 :5 gas use: in E3 2 :35 WE; 02:231. n15? 925a casualties: 025a Eaa 2:25 3;: 52: 2:25 3;: Ease u: 1. ii If 1: xi in ii an In in 1| 1| ii fl .1 fl Auguwmv dm>awac~ >cm>oUmm.| .i 1: Agzowmw _m>cw~c_ m>_ao.v _ mmmzm _ _ mama; Lagoon“ «macs _ amen; _ ax_agm +1432: Emma 32 ff: I ......... 32a 3:5 BafflffferOZS :ofifiYtSSmuEX- -38 _ ....:...._ _ _ 20:: 2.; a: _ m :3 .:1 ..::..._ _ as .x .2: as 5:: .E .4 as; .E 2.35 as; u :3: as; a a .3 .5 . :5 n .x .3 .2: 2.; _ m as; see as s E_ motes: is. _ _ b _ 2 : a a are: m.“ 1 EC approximately equal to ten, 1930; lam-‘5 1‘ Br Slocum 1 James, 1968)- hetueen 70° and 80° ’9 down just slightly ahe body's center at fl”Vi shorter the distance D body's center of oral/1 surface contact, assum 1985). The short hori projection of the body and the backward direc touchdown tend to redu maintain forward momen direction of the drive the center line of pro horizontal line travel Within the midsagittal imaginary vertical pla halos, Each foot sho u" its rEsoective side from the Center line 0 viii affect lateral ba center line of Progres 1914). The human body, 1 bl upproximately equal to the forward velocity of the body (Dyson, 1970; Tenn, 1930; James & Brubaker, 1972, 1973; Hay, 1985; D. Miller, 1978; Slocum & James, 1968). At contact, the lower leg creates an angle Jetween 70° and 80° relative to the perpendicular. The foot touches down just slightly ahead of the downward vertical projection of the Jody's center of gravity. The faster and more mature the run, the shorter the distance between the downward vertical projection of the Jody’s center of gravity and the point where the foot makes support surface contact, assuming a level surface (Dyson, 1973; Fenn, 1930; Hay, 1985). The short horizontal distance between the downward vertical projection of the body's center of gravity and place of foot touchdown and the backward direction the foot is moving at the instant of touchdown tend to reduce the braking action of contact. This helps naintain forward momentum since the foot is already moving in the direction of the drive at contact (Hay, 1985). Located on the ground, :he center line of progression is an imaginary, single straight iorizontal line traveling the same direction as the runner and falls vithin the midsagittal plane. The midsagittal plane of the body is that .maginary vertical plane that bisects the body into equal right and left valves. Each foot should strike the supporting surface parallel to and m its respective side of the midsagittal plane. Too great a variation ran the center line of progression in the placement of the support foot ill affect lateral balance and create a Weaving action relative to the enter line of progression (Dyson, 1973; Slocum D James, 1968; Wilt, 964). The human body, in a nonsupported state, behaves as a projectile and is governed by th 1935). The magnitude speed, height and ang force of gravitY- At gravity and the body first contact, flexic occurs at the ankle J touchdown (James 8: Br as the foot settles i Slight flexion is anal body moves forward m knee joint and plants drive the body "9 anc that launch the body musculature and progr extensors of the knee lanes & Brubaker, 197 .leg reaches its naxio takeoff. Le Action - Rec phases of the recover ootion of the leg dur t hen leg action in th l he" the leg enters t anon Entary continual 62 and is governed by the laws of physics pertaining to projectiles (Hay, 1985). The magnitude of the parabolic flight path is determined by the speed, height and angle of takeoff, any air resistance, and the downward force of gravity. At touchdown, to help absorb the downward force of gravity and the body weight on the support surface as the foot makes first contact, flexion occurs at the hip and knee and dorsiflexion occurs at the ankle joint. The knee is already flexed 30° to 35° at touchdown (James & Brubaker, 1972) and flexes another 10° (Fenn, 1930) as the foot settles into the midsupport phase of the drive interval. Slight flexion is maintained at the hip, knee, and ankle joints as the body moves forward over the foot. Then, extension begins at the hip and knee joint and plantar flexion occurs at the ankle joint helping to drive the body up and forward into the takeoff. The summation of forces that launch the body into the air begins in the lumbar spine-pelvic musculature and progresses sequentially into the extensors of the hip, extensors of the knee, and plantar flexors of the ankle (Dyson, 1973; James & Brubaker, 1972; Slocum & James, 1968). In most instances, the leg reaches its maximum extension as the foot leaves the ground at takeoff. Leg Action - Recovery Interval. The leg action during the three phases of the recovery interval involves reversing the direction of motion of the leg during each phase and, therefore, takes much more time than leg action in the drive interval (James & Brubaker, 1972, 1973). When the leg enters the first phase, the follow through phase, there is a momentary continuation of backward movement of the thigh segment. Ffevion at the knee b‘ flexor muscles of the subsequent contractiol its oaxinun extensifln position, the body re. the hip and knee move greatest plantar flex behind the body axis noveoent of the lower provides a controllinv optinuntining. Entel braking action and HUI lanes, 1968). Second and foot about the an swing to occur with gr not flexed (Hay, 1985; 1968; llilt, 1964). n: rearward swinging thiv and foot continue thei bUtt‘leS- The flexior through phase, progre, and knee flexion. The initial for“; beginning of the torwa the thigh Segment re“ horizontal, at the sa fl 63 Flexion at the knee begins as the recovery limb decelerates and the flexor muscles of the hip are stretched to a length most suitable for subsequent contraction. That is, at takeoff the lumbar spine reaches its maximum extension, the upper pelvis tilts to its most forward position, the body reaches its maximum rotation about the vertical axis, the hip and knee move to maximum extension, the ankle reaches its greatest plantar flexion, and the foot reaches to its farthest position behind the body axis (Slocum & James, 1968). This continued backward movement of the lower leg and foot serves two purposes. First, it provides a controlling factor so that the follow through occurs with optimum timing. Entering the follow through too soon would exert a braking action and would require strenuous muscular effort (Slocum & James, 1968). Second, the continued backward motion of the lower leg and foot about the knee shortens the limb, thereby enabling the forward swing to occur with greater speed and less effort than if the leg were not flexed (Hay, 1985; James & Brubaker, 1972, 1973; Slocum & James, 1968; Wilt, 1964). As angular momentum is being transferred from the rearward swinging thigh segment to the lower leg and foot, the lower leg and foot continue their backward movement until the foot is near the buttocks. The flexion that begins in the lumbar spine during the follow through phase, progresses to backward upper pelvic tilt, hip flexion, and knee flexion. The initial forward movement of the thigh segment marks the Jeginning of the forward swing phase. During the forward swing phase :he thigh segment reaches its maximum height, relative to the vorizontal, at the same moment that the opposite leg is completing its takeoff phase. The V combined with the dow increases the support (Dyson, 1973; James & begins after the thig body is in flight. T backward, transferrin forward. Hamstring c reaches its most forw approximately 35° of direction of travel f touchdown (James & Br Arm fiction. The in the takeoff phase ‘ up through the suppor‘ the vertical axis of ‘ in one direction untir the rotation reverses Pelvic rotation must I a nd synchronous arm 51 Sfeeds shoulder rotati 1Orces of the legs lb 1 er - Efore is an ineffi Tlllln' xng. 1” Sprint rx st 64 takeoff phase. The vigorous upward and forward drive of the thigh, combined with the downward and backward movement of the drive leg, increases the support surface reaction forces, thereby increasing speed (Dyson, 1973; James & Hrubaker, 1972, 1973). The foot descent phase begins after the thigh segment has reached its maximum height and the body is in flight. The thigh segment begins to move downward and backward, transferring angular momentum to the lower leg as it swings forward. Hamstring contraction decelerates the lower leg as the foot reaches its most forward position (Brandell, 1973). The knee maintains approximately 35° of flexion as the total leg completes a change in direction of travel from forward to backward in preparation for touchdown (James & Brubaker, 1972, 1973). Arm Action. The downward and backward driving of the support leg in the takeoff phase sets up a line of reaction from the support surface up through the support leg that creates a rotation of the pelvis about the vertical axis of the trunk. This rotation of the pelvis continues in one direction until the opposite leg pushes against the ground, then the rotation reverses direction. For efficient running to occur, this pelvic rotation must he counter balanced through effective, compensatory and synchronous arm swing (Hay, 1985; Housden, 1964). At slow running speeds shoulder rotation also is effective in absorbing the rotational forces of the legs. However, shoulder rotation requires time, and therefore is an inefficient method of force absorption for sprint cunning. In sprint running, it is important to keep the shoulders steady and use forceful arm action to absorb the rotational force of the pelvis (Hay. 1995; H1 The unisr ““5 " whereas, the lower ar front. This slight < natural hand 01 the L that is slightlv dies the cross-body swing body build and runnir not cross the midline cross-body movement 5 more than shoulder hi line. Elbows may be swing and should rela 197.1; Hay, 1985; Hick flexion is controlled during the forward sw is that as limb movem flexing the limb join ’EdUEES the resistanc limb to move faster t dfilled force (Hay, 1 For arm swing to in the absorfltion of direction that will c important When ”mm“ 1 mrward and backward pelvis (Hay, 1985; Hinrichs, Cavanagh & Williams, 1983; Wilt, 1964). The upper arms move more or less straight forward and backward, whereas, the lower arms will have a slight cross-body direction in front. This slight cross-body swing of the lower arms is due to the natural hang of the upper limbs which results in a forward arm swing that is slightly diagonal rather than directly forward. The extent of the cross-body swing of the lower arms varies somewhat with individual body build and running speed (Broer & Zernicke, 1979). The hands should not cross the midline of the body. The faster the run, the less cross—body movement should be made by the arms. Hands should swing no ore than shoulder high in front nor more than a foot behind the hip line. Elbows may be flexed as much as 90° at the apex of the front swing and should relax slightly as they move past the hip line (Dyson, 1973; Hay, 1985; Wickstrom, 1983; Wilt, 1964). The extent of elbow flexion is controlled by the same principle that governs knee flexion luring the forward swing phase of the recovery interval. The principle 5 that as limb movement increases, shortening the radius of the limb by lexing the limb joints reduces the moment of inertia which in turn educes the resistance to angular movement and therefore enables the imb to move faster than if it were extended, given the same amount of pplied force (Hay, 1985; Simonian, 1981). For arm swing to be an effective aid in force production as well as a the absorption of counter rotary forces, motion must be in the traction that will contribute positively to the running speed. It is xportant when running fast that the arm movement not only be in a vrward and backward line of direction, but also have significant upward and downward accelera‘ two arms complete the of the body, they alsv with the legs, the upx component of the suppx 1964). running is adapted to unless one needs to oi the runner generally a feet under the body pa running form gives the from the support surfe "fright position. Mai Important in achieving astride. to smooth, effici (isolacenent in the fr the sagittal plane. 1 evaluated by the follo “”119 a running cycle nolament of the center alternate“ transferre ateral movements shou fork of the DDStUral m nd downward acceleration. Working synchronously in opposition, as the wo arms complete the forward and backward swinging motion on each side f the body, they also move downward and upward. Properly synchronized ith the legs, the upward movement of each arm adds to the vertical omponent of the support leg drive at takeoff (Dyson, 1970; Hopper, 964). Body Position and Displacement. The body position assumed while unning is adapted to the purpose for which one is running. However, nless one needs to make specific adjustments in the running situation, as runner generally maintains an upright trunk position and tracks the set under the body parallel to a line of intended travel. Efficient inning form gives the illusion of forward lean as the foot pushes off 'om the support surface, but the trunk essentially maintains the near fright position. Maintaining a near upright trunk position is aportant in achieving optimum flexion and extension of the legs during stride. In smooth, efficient running there is minimal lateral body splacement in the frontal plane and minimal vertical displacement in e sagittal plane. These lateral and vertical displacements are aluated by the following changes in the body's center of gravity ring a running cycle. In the frontal plane, some side to side ement of the center of gravity is expected as the body weight is ernately transferred from one foot to the other. However, these eral movements should be kept at a minimum in order to reduce the k of the postural muscles in maintaining body balance, to reduce the stress on the Likewise, vert aminimum. Ha since the grea greater the po lle). Researche lravity follow body synchronov takeoff phase_ Place while th. the 1’0in the 1 and falling to, 1995 causes shx 1" ”(if accori P051tions “Us, first diagonal] during Each rur llVaments, ther of 9”MY witf were Mad 1 movenm 0, the SPEed, That is the body's CEnt “than” it Komi tress on the ankles, knees, and hips, and to avoid a weaving motion. ikewise, vertical displacement in the sagittal plane should be kept to minimum. Maximum forward displacement of the total body is desirable ‘nce the greater the forward displacement in the sagittal plane, the eater the potential speed, other things being equal (Slocum & James, 68). Researchers are in agreement that the path of the body's center of 'avity follows a wavelike pattern in the sagittal plane. The whole xdy synchronously rises reaching its maximum height just after the keoff phase. A rise in the center of gravity within the body takes ace while the runner is in contact with the ground. Once in the air e body, the same as any projectile, follows a parabolic path rising d falling toward the ground (Hay, 1985). The action of the arms and gs causes shifting of the center of gravity within the body itself. fact, according to Fenn (1930), the synchronous changing limb itions causes the body's center of gravity to move within the body, st diagonally upward and backward, then downward and forward, twice ing each running cycle. Due to the influence of arm and leg ements, there is actually greater vertical range in the body's center gravity within the body than the relative up and down movement of the ner’s head (Housden, 1964). The range of the vertical (up and down) ement of the body's center of gravity is inversely related to running ed. That is, the faster the running speed the less rise and fall of body’s center of gravity for any given performance (Fenn, 1930; hanen & Komi, 1978; R.A. Mann & Hagy, 1980; Rapp, i963). erected tbeproduct of dhtmce cover fut and stridx penod by the x snarate distar 1. The t downw front suppu 3- The f cente ~1- Thel Porti 0t th Prods “Udelength m moportion to av 19951- within) ueachieved by imhnnfyjng one cruses SEVEral l. The time it i. More time is i. like“;Er “to 4a Effects of Speed (Velocity) Changes. Running speed (velocity) is the product of stride length and stride rate. Stride length is the distance covered from touchdown on one foot to touchdown of the opposite foot and stride rate is the number of strides taken within a given time period by the runner. A runner's stride length is the sum of three separate distances: 1. The takeoff distance is the horizontal distance that the downward vertical projection of the center of gravity is in front of the takeoff foot at the instant the foot leaves the support surface, IQ - The flight distance is the horizontal distance that the body‘s center of gravity travels while the runner is in the air, and 3. The landing distance is the horizontal distance that the portion of the foot which first contacts the support surface of the touchdown foot is forward of the downward vertical projection of the body's center of gravity (Hay, 1985). tride length and stride rate are interdependent and must be in correct roportion to achieve maximum running efficiency (Dyson, 1970; Hay 985). Within human physical limitations, increases in running speed re achieved by increasing both stride length and stride rate or by ntensifying one parameter without decreasing the other. As speed in- reases several related factors change: The time it takes to complete one stride decreases. More time is spent in flight and less time in support. Greater extension of the support leg occurs at takeoff. The recovery leg achieves a smaller knee angle, moves faster, and runnin discus 0n runx aechanx‘ have v,- lnatomi prerim fathoyo that whr "hethEr aVergge 5118911 if SuhlEcts 69 the thigh segment moves higher relative to the horizontal before beginning descent to touchdown. The vertical displacement of the body's center of gravity decreases. The angular velocities at the leg joints increase. The angular displacements of the segments about the hip and knee increase while the angular displacements of the segments about the ankle decrease. The angular displacement of the trunk also decreases. m1e 3 summarizes the research that describes changes in the running ctors as speed increased. Characteristics of Mature RunningiForm. In compiling reviews of nning research, Dillman (1975), Wickstrom (1983), and Williams (1985) scussed the difficulties encountered in attempting to interpret data running skill from the variety of protocols used to investigate the :hanics of running. Williams (1985) identifies 10 variables which may e varying influence on results: speed, sample size, gender, age, atomical and muscular characteristics, ability or state of training, erimental conditions and procedures of analysis, fatigue, handicap/ hology, and footwear/surfaces. Dillman (1975) particularly noted t when comparing the research on the effects of speed one should note ther the subjects were accelerating (continually increasing the rage horizontal speed) or moving at a constant (average horizontal) ed throughout the running cycles. Researchers often reported how 'ects ran at various constant speeds, within a certain range, which ‘discretely' incremented, without indicating if the same mechanical 7 0 Tatxle 3 Summary of Running Factors that Change with Increases in Speed (Velocity). Increase (+)/ Factor Decrease (-) Reference Stride Length f Dillman, 1975; Fenn, 1930; Hanson, 1975; Hogberg, 1952; Kurakin, 1972; Luhtanen 11x Hedi, 1978; D. l‘liller, 1978; Nelson 1: Gregor, 1976; Rapp, 1963; Saito, Kobyashi, Hiyashita, & Hoshikawa, 1974; Slocum & James, 1968; Wickstrom, 1983; Williams, 1985. Stride Rate + Dillman, 1975; Hogberg, 1952; Kurakin, 1972; Luthanen k Komi, Stride Tine Thigh Segment Height Minimum Knee Angle Speed of Leg Recovery Support Time Flight Time 1) Support Time) Greater Leg Extension at Takeoff Vertical Displacement Angular Velocities Angular Displacement Hip Knee Ankle Trunk Ila-+- 1978; D. fliller, 1978; Nelson 8 Gregor, 1976; Saito, et a1. 1974; Slocum & James, 1968; Hictstrom, 1983; Williams, 1985. Dillman, 1975; Hoskikawa, 1973; Kurakin, 1972; Nickstrom, 1983. Dillman, 1975; Fenn, 1930; Hanson, 1975; Hoskikawa, 1973; D. Hitler, 1978; Wickstrom, 1983; Williams, 1985. Dillman, 1975; Hanson, 1975; D. Miller, 1978; Nickstrom, 1983; Williams, 1985. Hanson, 1975; Hoskikawa, 1973. Dillman, 1975; Hanson, 1975; Hoskikawa, 1973; Kurakin, 1972; Luhtanen 8 Kent, 1978; D. Hitler, 1978; Nelson & Gregor, 1976; Slocum & James, 1978; Hickstrom, 1983; Williams, 1985. Dillman, 1975; Hanson, 1975; Hogberg, 1952; Kurakin, 1972; Luhtanen & Kooi, 1978; D. Hitler, 1978; Wickstrom, 1983; Nilliams, 1985. Dillman, 1975; Hogberg, 1952; D. Hitler, 1978; Wickstrom, 1983. Dillman, 1975; Fenn, 1930; Luhtanen k Komi, 1978; R.A. Mann 8 Hagy, 1980; Rapp, 1963; Wickstrom, 1983. Hoskikawa, 1973; D. Miller, 1978. Hoskikawa, 1973; Wickstrom, 1983. Hoskikawa, 1973; Wickstrom, 1983. Hoskikawa, 1973. Hoskikawa, 1973. 71 :hanges were evident if a runner was continuously and rapidly accelerating through the same range of speeds. Dillman (1975) and Wickstrom (1983) advised that a reviewer should note whether overground or treadmill running was used in a study. Conflicting results were obtained in the research that was specifically designed to compare overground and treadmill running (Dal Monte, Fucci, & Manoni, 1973; Elliott & Blanksby, 1976; Nelson, Dillman, Lagasse, & Bickett, 1972). Elliott and Blanksby (1976) equated jogging and running overground with treadmill jogging and running in males and females. No differences were noted among the subjects in stride length, stride rate, support and flight times at jogging speeds, but at running speeds stride length decreased, stride rate increased and flight time was less when running on the treadmill in contrast to running on the ground. Nelson et al. (1972) found the support period increased while vertical velocity decreased and that vertical and horizontal velocities were less variable 1on the treadmill than on overground running. Nelson et al. (1972) iconcluded significant mechanical changes did occur when running on the treadmill as compared to overground running. 0n the other hand, Dal Monte et al. (1973) concluded running technique was no worse on the treadmill than overground because there were no significant kinematic differences evident within the two running forms. The type of subjects used (good vs poor, elite runner vs recreational jogger) and the subjects' familiarity with treadmill running also may have affected the results and must be considered when contrasting results of research on mature running form. Despite the inconsistencies and differences among the subjects and 72 3cols used, certain characteristics of mature running form are ent throughout the literature. Dillman (1975) and Wickstrom (1983) summarized the characteristics of mature running form. These two ors conclude that relative to the immature runner, the mature er: Has a longer length of stride relative to the physical dimensions of the body. Spends less time in contact with the ground. Has a smaller vertical displacement of the body. Has greater angular velocities and complete extension of the leg during the takeoff phase of the drive interval. Has greater knee flexion during the forward swing phase of the recovery interval. Has a more efficient sequential backward rotation (with respect to the trunk) of the leg just prior to touchdown during the foot descent phase of the recovery interval. Has less knee flexion and ankle dorsiflexion in the support leg after the foot makes contact with the ground. Has thigh segment reaching a greater height relative to horizontal during the recovery interval. Has touchdown of the foot closer to the downward vertical projection of the body's center of gravity. Maintains only a very slight forward lean of the trunk throughout the running cycle. Swings the arms forward and backward in synchronized opposition to the leg action allowing the hands to move toward the body's midline 73 on the forward swing. This review of literature has reflected the interdisciplinary iroach of the present study by recapitulating the biological and ychological origins of developmental stage theory; the Piagetian iteria for stages (hierarchization, structural wholeness, integration, nsolidation, and equilibration) and their application to motor skill velopment; the major early research in motor skill development; the velopmental staging research for fundamental motor skills; the velopment of running from both developmental staging and developmental omechanics research; and finally, the biomechanical analysis of the ture running form to serve as a basis for measuring skill development. Physical educators have taken two approaches to the study of the velopment of running. Physical educators specializing in velopmental biomechanics have analyzed running in order to describe fferences and trends in skill performance on the basis of age or der, kinematic, and kinetic variables. Physical educators cializing in motor development have staged skill development ording to specific characteristics observed in skill development. ependently, motor development and developmental biomechanical roaches to motor skill maturation research have yielded valuable ormation about the development of fundamental motor skills in 'ldren. Both approaches have provided quanititative and qualitative ormation (direction and shape of developmental changes, mathematical rameters of developmental curves, and distance, speed, and velocity ores on skill performance) by age or grade and gender. Developmental omechanical studies have provided kinematic and kinetic information on at is happening to body segments and joints during skill performances children of differing ages or grades and gender. Motor development aging studies have identified age related, but not age dependent, anges for key descriptive characteristics in developing fundamental tor skills in boys and girls. The key descriptive characteristics entified by motor development staging studies are generally synonymous -kinematic variables investigated by age or grade level in velopmental biomechanics studies. However, biomechanical analysis of e identified developmental stages of various fundamental motor skills defined has yet to be done. For the motor development researcher, a omechanical analysis of the developmental stages of fundamental motor ills would help determine the extent and significance of mechanical fferences observed in developing skills. For the developmental mechanics researcher a biomechanical analysis of the developmental ges might begin to explain differences, or lack of differences found previous research based on age or grade level. The present study an the process of biomechanical analysis of the developmental stages fundamental motor skills by investigating selected kinematic and hropometric variables for the skill of running. Its purpose was to ine which specific variables, if any, differ among the four stages of ning as well as between the running performance of boys and girls. Chapter III Methodology The purpose of this study was to identify differences in selected 1ematic variables among the four developmental stages of running in aschool age boys and girls. This chapter will describe the subjects ad in the study, the protocols for the anthropometric measurements, Icedures for the filming session, data reduction, analysis of data, Tresearch design, and statistical treatment of the data. jects A pool of potential subjects for each developmental stage of ning was identified during the fall 1985 testing of all enrollees in Early Childhood Motor Development Program (E.C.P.) in the School of lth Education, Counseling Psychology, and Human Performance at higan State University. Each fall and spring, enrollees are tested stage of development in ten fundamental motor skills, distance in long jump, and performance times for balancing on each foot, an lity run, and a lS/SO-yard run. The 15/30-yard run requires a 1ing start and times are taken at the 15—yard and 30—yard marks using ilit time stopwatch. During the fall 1985 sessions, the author was 75 76 present at all testing sessions in order to identify enrollees exhibiting the classic stages of running as previously described. After a child was so identified, the accompanying parent was given a brief explanation of the study and asked for verbal permission to include that child in the appropriate subject pool. Since few program enrollees demonstrate a stage-one run, younger siblings of children being tested were screened, with parental permission, to create a subject pool for stage-one runners. Because there was approximately a six—month interval between the fall testing and the actual filming, all children enrolled in the E.C.P. program during the spring term were rechecked for running stage approximately one month prior to the filming. This verification was conducted at one of the teaching stations during the weekly E.C.P. classes which the children attended. Running stages were determined and 15/30 yard run times were collected. The pool of potential subjects for each running stage was adjusted for children who had moved into transition since the September screening. Between this second screening and film data collection, the author visited the weekly classes in which the selected subjects were enrolled. These visitations helped establish a positive rapport with the children in preparation for the filming sessions. Visitation of E.C.P. classes during the week prior to filming provided opportunity for a final verification of the stages. From the four subject pools, one boy and one girl (n=8) were selected who nearest represented the modal age for each stage (stage 1 = 18—23 months, stage 2 = 30-35 months, stage 3 = 42-47 months, stage 4 = 54-59 months) (Early Childhood, 1985). Parents were contacted by telephone to ascertain interest in bringing their children in for a filming session. If the response was positive, a filming time was tentatively scheduled and the parents were sent information detailing the study. Copies of the parent information materials are contained in Appendix B. If the parents had any questions or concerns after having read these materials, they were requested to contact the author. Testing Procedures All subjects were scheduled for a single filming session held at the Center for the Study of Human Performance in Erickson Hall on the campus of Michigan State University. Upon their arrival, informed consent forms and film release forms were collected from the parents, and the children were given a brief tour to familiarize themselves with the lab filming area and the film personnel. With the youngest children a brief play period with foam balls helped them become more comfortable with the film personnel. Testing procedures for each subject involved the collecting of anthropometric data and completion of two film trial runs. Specific explanations for each procedure follow. Anthropometric Measurements. Prior to the actual filming, selected anthropometric measurements were taken on each subjeat for statistical analysis of the relationship of body segment lengths to running stage. Dressed only in a swim suit (or diapers), the subjects were weighed on a weight-beam scale. Weight was measured to the nearest one-tenth kilogram. The subjects then were shown the measuring tools, a bow caliper and an anthropometer, and were told that these would be used to find out “how big you are." For each measurement the children were given a demonstration of how they should try to stand or sit. If they were unable to copy the position on their own they were gently placed into the correct position. Measurements to the nearest millimeter were taken on both sides of the body following procedures outlined by Seefeldt, Haubenstricker, Brown, and Branta (1983) and recorded. The selected anthropometric measurements were: standing height, sitting height, shoulder width (biacromial diameter), hip width (biiliac diameter), upper-arm length (acrom-radiale), forearm length (radio- stylion), hand length, total upper extremity length, foot length, shank length, total leg length, and trochanteric height. A detailed description of the measurements can be found in Appendix C. Cinematographic Procedures. After the anthropometric measurements were recorded the investigator marked the body joints with 3/4 inch round, contrasting markers. The joint markers were applied to assist in achieving more precise and uniform location of body joints during data analysis (Ulibarri, 1984). The subjects ran from left to right as viewed through the field of view of the sagittal camera (side view). Joint markers were placed on the lateral side of the right ankle, knee, and hip, and on the medial side of the left ankle, and knee. Lateral, medial, and front sides of each elbow were marked as were the front, lateral, and back sides of each shoulder. Wrist joints were marked with Specifically designed contrasting 3/4 inch elastic bands to insure easier identification of this joint from any position. The front of each hip, knee, and ankle also were marked. The children also received a special “belly-button" marker (Mersereau, 1974). They were told they couldtouch and take home this novelty marker, but the other markers were to be left untouched. The running surface in the staging area of the lab was marked to coincide with the filming field of view and to create a running track so the children could be instructed to run between the lines. Cross lines were placed one meter apart down the length of the runway. Along with the filming of a meter stick prior to the actual filming of a subject, the cross lines provided a known distance reference on the film for use in data analysis. Figure 14 illustrates the track area and placement of the cameras. The children were shown the running track and given a practice run. Prior to the actual filming of the running, the children were given an opportunity to listen to the camera sounds while the meter stick was filmed. This meter stick was used as the linear conversion factor in the planar analysis. Once familiar with the sound, the subjects were much less distracted during the filming trials. The children were then filmed from the sagittal (side view) and frontal planes (front view) simultaneously while they ran down the marked track to one of their parents who was waiting beside the frontal plane (front view) camera. Orange cone markers were placed on the end of the running track nearest the frontal plane (front view) camera, just inside the field of view of the sagittal plane (side view) camera. The children were asked to run as fast as they could, straight between the cones, and give their parent a big hug. Except for the addition of the cone markers and the marked track, the directions were identical to the ones . mcwu Esau 80 .mmcm ocfleflsw may we cmda Looflu .¢~ mcsmfiu .:2>m28 «cacao acmdm -gu_o~m ‘ s a u , amaze sucaaawtcs \ _ x a n , a x _ a a a , fill a _ , mac¢ a. n ,, acmamusmam: . _ , owcuu.oaoczu=c as n ,, ~ _ a a _ I ~ _ ’ illlllll g a _ / a _ x _ a, _ a \ _ z u _ , a _ , a \ _ a \\ _ a \\\~~ _ a \\\ so — a “a: aomaam . . . \ hxnniisnliiliiinii ii ATIIIIII I I I I cowuumcwa ~x~_> “cock, I I I I o wcwccsm “cacao madam HauCOca mucmom . waxes =a_sausucs=aas scabs ~.cc aces ease used f Childh lines in a s throug of two child field (or an qualit T EngSu lens 01 = -15m 20m (1. 1/1000' placed camere DErpen, tiller; “an; 81 used for the semiannual testing of the children enrolled in the Early Childhood Motor Skills Development Program. The cone markers and floor lines marking the running track were added to keep the children running in a straight line to minimize perspective error as each child moved through the field of view of the sagittal camera (side view). A minimum of two good trials was filmed. Additional tria1(s) were filmed if the child failed to achieve a full run or broke stride before exiting the field of view of the sagittal camera (side view). The trial selected for analysis was the one that demonstrated the best performance or quality of film from the sagittal view (side view). Two LDCAM cameras equipped with F .12-120mm zoom lenses were used in the filming. The cameras were mounted on separate tripods and each connected to a master switch with a 25 foot heavy duty extension cord. Kodak 4-X Reversal 7277 high speed 16mm film was used for the filming. iThe film rate was 100 frames per second with a 120° shutter angle and a 5.6 f-stop for the sagittal plane (side view) camera and a 4 f-stop for the frontal plane (front view) camera. This created a l/SOOth second exposure time and eliminated blurring of the movement on the film. The lens on the frontal plane (front view) camera was set at 7m (lens length = .15m) and the lens on the sagittal plane (side view) camera was set at 20m (lens length = .16m). Timing light boxes capable of measuring up to 1/1000th second, plumb lines, and subject identification boards were placed each camera's field of view. The sagittal plane (side view) camera was placed on a tripod 1.06 meters high and 12.4 meters from and Perpendicular to the running track. The frontal plane (front view) camera was on a tripod 1.12 meters high and was perpendicular to and cente front resen view) point two (i backd contr assis after lab Yield analy digit Guard with draft digit illus disk lllchi B2 centered between the two lines that marked the running track. The frontal plane (front view) camera was 6.27 meters from a point that rep- resented the center of the field of view for the sagittal plane (side view) camera so that a right angle was formed where the central focal point from each camera met (see Figure 14). The staging area was lit by two banks of ceiling flood lights and a gray CBS curtain provided the backdrop. Skill eliciting was done by the researcher, while camera control was handled by an expert in cinematography. Four graduate assistants (two during the morning filming sessions and two in the afternoon filming sessions) provided general technical assistance. Data Reduction and Analysis The analysis first required data reduction of the film. This yielded the needed raw data to complete the kinematic and statistical analyses according to the research design. Film Analysis. Data reduction was performed by the process of digitization. The film was projected onto a drafting table by a Van Guard Analyzer projection head. A sonic stylus was used in conjunction with two strip microphones set perpendicular to each other on the drafting table. Every frame for one running cycle for each leg was digitized. Seventeen data points were input for each frame as illustrated in Figure 15. Data were read directly to an IBM PC floppy disk then transferred to the Cyber 750 mainframe computer at the Michigan State University Computer Center for analysis using the Fl "re 15 599lenf,_ liabs. 83 ' ' ' d end points for digitizing body F g 15. Numbering of the de51gnate . ' . . segzests. Solid line indicates right limbs, dotted line indicates left limbs. biomechanics of segmental displacement using the Fi factor was c was verified angles, segmi as illustrati midpoint of ‘ Figure 17. | touchdown am minimum knee Fllure 20) dl measured in a and forearm . Figure 21, f maximum for,” Figme 21' DlSplacE the dlSPlacem for mmpirisg lEak angular colflarison am the sagittal illsg ("Ea horizontal di 84 biomechanics program, KINEMAT. This program supplied data for analysis of segmental and body centers of gravity, and linear and angular displacements, velocities, and accelerations. Raw data were smoothed using the First Central Taylor Expansion Series Equation. A conversion factor was calculated and used in the linear calculations. Frame time was verified by the timing lights. To determine lower extremity joint angles, segmental inclinations were measured relative to the horizontal as illustrated in Figure 16. Trunk inclination was measured from the midpoint of the hip joints relative to the horizontal as illustrated in Figure 17. Lower extremity segmental inclinations were evaluated at touchdown and takeoff during the drive interval (see Figure 18), and at minimum knee angle (see Figure 19) and maximum thigh segment height (see Figure 20) during the recovery interval. Upper extremities were measured in a similar manner. Segmental inclinations for the humerus and forearm were measured relative to the horizontal as illustrated in Figure 21. Humerus and forearm inclinations were evaluated at the maximum forward swing and at maximum backward swing as illustrated in Figure 21. Displacements and velocities were investigated in two ways. First, the displacements and velocities for upper and lower limbs were tabled for comparisons among the four running stages. Second, the sequence of peak angular velocities in the lower extremities were determined for comparison among the four stages. All data were calculated from film of the sagittal (side) view. Also measured from the sagittal film (side view) data was the morizontal distance between the lead foot at touchdown and downward ”4M. InterVal: (e Figure 16. Segmental inclinations for analysis during the drive interval: (a) foot, (b) shank, (c) thigh. “4m. 86 Figure 17. Measurement of trunk inclination. Fl fire 13. ‘ Maswe’aeflts ’ takeoff. 87 ' tal inclination ' ' lower extremity segmen F' 18. Selected p051tions for . . . hdown diggfifEEEhts for analysis during the drive interval. (a) touc , (b) takeoff. Film. Measurem nimimun knee angle c 88 I A.."l ... a ‘-n., o 1' ‘ ..""".’-'I'. ' ,. ..., .s .' . .., . . - ....0' . . -.......n"" oA-o... o a n a Figure 19. Measurement of segmental inclinations for analysis of minimum knee angle during the recovery interval. ":&;;Am*¢— Fiur 20_ "Easure n\ e 19h segment hEigh 89 E192££_29, Measurement of segment inclination for analysis of maximum thigh segment height during the recovery interval. 90 ‘o '- . Figure 21. Measurement of upper extremity segment inclinations for analysis of (a) humerus and (b) forearm at maximum backward and forward swing. vertical projectior Figure 22). This c Additionally, the 5 running velocity we From the from) drawn midline and l forearms, humeri, ' shoulder joints we: cycle for each leg the measurements w. recovery intervals and maximum thigh if" measurement of SEdimental centers shanks, feet, and W kinematic variable displacements and relation to the ,0 boys and girls. 1) f' . liming 5955mm lahlES’ while the MeasureS Were the multiple dePEndent 9°” trials. The 91 vertical projection of the body's center of gravity at touchdown (see Figure 22). This distance was measured for each foot at touchdown. Additionally, the stride length and stride rate were measured and running velocity was calculated from the sagittal view (side view) film. From the frontal plane (front view) film the distance between a drawn midline and the segment center of gravity for the hands, forearms, humeri, thighs, shanks, feet, and the midpoint betwwn the two shoulder joints were evaluated at selected points during the one running cycle for each leg analyzed. During the drive intervals for each leg the measurements were taken at touchdown and takeoff. During the recovery intervals, the measurements were taken at minimum knee angle and maximum thigh segment height. Figure 23 illustrates the procedure for measurement of the distances between the drawn midline and the segmental centers of gravity for the hands, forearms, humeri, thighs, shanks, feet, and the midpoint between the two shoulder joints. Research Design. This investigation was designed to study selected kinematic variables (positions in space and linear and angular displacements and velocities) and anthropometric measurements in relation to the four developmental stages of running in preschool age boys and girls. Data were collected during a single measurement and filming session. Running stage and gender were the independent var~ iables, while the selected kinematic variables and anthropometric measures were the dependent variables. This created a 4 x 2 design with multiple dependent variables. Film data were obtained for at least two good trials. The best trial was selected for analysis. Fi ure 22' Heasv Vertical Project touchdflwm 92 . o . c ... .- -.., ...... —.——_____,...‘_.La -" .- Figure 22. Measurement of the horizontal distance between the downward vertical projection of the body's center of gravity and the foot at touchdown. 93 Figure 23. Measurements for the relationship of segment center of gravity of the hands, forearms, humeri, thighs, shanks, and feet with the drawn midline (center line of progression). Missouri system 18! Missouri-St. Louis 1985b) statistical considered signifi Data were ana cycle for each leg significance of th running. Univaria Post hoc tests the anthropometric, or Correlations were stride length and Stride rate and rv Velocity. 94 Statistical Analysis. Data were analyzed on the University of Missouri system IBM 3278 mainframe computer at the University of Missouri—St. Louis Computer Center using the 898 Version 5 (1985a, 1985b) statistical programs. A p value equal to or less than .05 was considered significant. Data were analyzed at specific points during one complete running cycle for each leg using multivariate analysis to determine the overall significance of the differences in performance among the four stages of running. Univariate F, planned comparison tests and, where indicated, post hoc tests then were used to define which specific kinematic, anthropometric, or both variables differed between the four stages. Correlations were performed to determine the relationships between stride length and stride rate, stride length and running velocity, stride rate and running velocity, and trochanteric height and running velocity. Tin interdisc development in yo specifically sele cinematography, w developmental sta gender groups. K represented the d stages of running discussed in the included: (a) the stride time, cycl left cycle time, 1 lb) the segmental cYcle; (c) the di! b‘ldY center of gr. peak angular Velov center of gravity linear and angular Chapter IV Discussion of Results An interdisciplinary approach was used in this study of running development in young children. Biomechanics research techniques, specifically selected kinematic-analysis procedures using high speed cinematography, were used to evaluate the differences among the four developmental stages of running (Seefeldt et al., 1972) and between gender groups. Kinematic variables selected for investigation represented the distinguishing characteristics of the developmental stages of running. Seven major areas were investigated and will be discussed in the following pages. These areas of investigation included: (a) the running descriptors of stride length, stride rate, stride time, cycle length, total right-left cycle distance, total right~ left cycle time, running speed, and selected anthropometric measures; (b) the segmental inclinations at selected points during the running cycle; (c) the distance between the downward vertical projection of the body center of gravity and the foot at touchdown; (d) the sequence of peak angular velocity for leg segments; (e) the midline-limb segment center of gravity distance at selected points during the running cycle; (f) the temporal analysis; and (g) limb segment displacements, both linear and angular. The variables were analyzed for each leg in order 95 to 0) data Runni 96 to observe differences between right and left limb actions. Tabled raw data for the subjects studied can be found in Appendix E. Runnino Descriptors. Selected anthropometric measurements were analyzed for stage effect. Although trochanteric height was the leg measurement of choice for study, total leg length was also analyzed to compare with results from previous research on development of running in young children. Stage effect p values ranged from .0346 to .4372 and gender effect p values ranged from .0949 to .0662 for standing height, trochanteric height, total leg length, biacromial width, and biiliac width. Trochanteric height was statistically the same among the stage one, two, and three runners and the stage two, three, and four runners. The trochanteric height of stage one and four runners differed significantly at the p (.05 level (see Tables 4 and 5). There was no statistical difference for gender on trochanteric height. It is difficult to discern why the stage—effect significance occurred in trochanteric height and not in total leg length, unless the small number of subjects (and/or the .05 significant level used) in the study affected these factors. Perhaps analysis of both measures in future research should be performed to ascertain if the difference really is significant or is due to some other variable(s). Mean stride time, stride length, stride rate, cycle length, total right-left cycle distance and total right-left cycle time were evaluated (see Tables 6 and 7). P values obtained for stage and gender effect Table 4 Analysis Table 5 “Mm 97 Table 4 Analysis for Stage Effect on Selected Anthropometric Measures (cm). STAGE F 1 2 3 4 (3,3) STANDllfi HEIGHT 80.600 93.500 97.600 106.950 5.77 .0920 TRID’M'TERIC 33.400 44.350 44.350 48.900 12.60 .0346 fElBHT TOTAL LEG LENGTH 30.550 40.400 41.150 45.050 9.51 .0484 (felur + shank} , l BIACRDHAL 14le 19.600 21.650 22.800 25.100 1.98 .2950 1311le 11le 14.800 16.500 17.000 17.300 1.22 .4372 Table 5 Analysis for Gender Effect on Selected Anthropometric Measures (cm). GENDER F MALES FEMJES (1,3) STMDINE tEIGHT 90.175 93.150 0.44 .5539 TRIDMTERIC 42.300 43.200 0.23 .6660 fEllifT TDTN. LES LENGTH 36.875 41.700 5.81 .0949 (fear + shank) BIRCRM HIDTH 22.325 22.250 0.00 .9662 BITLIAC HIDTH 16.525 16.275 0.06 .8207 Table l dnalysi Table 1 98 Table 6 Analysis for Stage Effect on Selected Running Measurements. STAGE F n 1 2 3 4 (3.3) EAR STRIDE THE (5) 0.240 0.232 0.227 0.212 0.450 .7371 l‘EAN STRIDE LEhETH (cm) 41.080 50.790 66.470 85.700 6.370 .0813 MEAN STRIDE RATE (l/s) 4.210 4.340 4.420 4.720 0.400 .7650 [AN CYCLE LENGTH (co) 78.430 100.240 130.300 170.300 6.300 .0842 TOTPL RIGHT-{EFT CYCLE DISTMCE (cl) 117.880 154.070 197.760 252.600 6.250 .0833 TOTAL RIGHT-LEFT CYCLE THE is) 0.710 0.700 0.685 0.630 0.650 .6337 Tab 1 e 7 Analysis for Gender Effect on Selected Running Measurements. semen F e mu: FEMALE (L3) icon STRIDE me is) 0.241 0.215 2.280 .2278 new STRTDE LENGTH (c) 1.4.495 57.522 0.810 .4534 new STRIDE more (4751 4.192 4.652 1.000 .2721 teen CYCUE cavern (ca) 127.090 112.540 0.1340 .4244 rorw RIGHT-LEFT cvue misrmce (cn) 139.910 171.550 0.630 .4849 Tom RIGHT—LEFT CYCLE TIME (51 0.715 0.647 2.550 .3344 ran sta ten tot 198 198 501 nor val for non 6.5 ton lenv Ddt‘. cm), ten.- Htal Mich nged from .0813 to .7650. However, a clear developmental trend across ages can be observed for all variables. Males had longer stride ngth, cycle length, total right-left cycle distance, stride time, tal right-left cycle time, and lower stride rate than females. These ends are in agreement with previously reported research (Amano et al., 83; Beck, 1966; Brown, 1978; Clause, 1959; Dittmer, 1962; Fortney, 80; Glassow et al., 1965; Mersereau, 1974, 1977; Miyamaru, 1976; and ith, 1977). Running cycle length, stride length, stride rate, and stride time re also analyzed for within subjects right-left differences factor. P lues ranged from .1031 to .5287 for stage effect and .0367 to .7708 r gender effect (see Tables 8 and 9). Follow up test for p<.05 were in significant. The right running cycle was slightly longer (2.16 to 51 cm) than the left across all stages. Right stride length was mger (2.07 to 7.71 cm) in stages one, two, and three; left stride ngth was longer (3.60 cm) in stage four. As expected, this same ttern was seen in stride time. The opposite pattern is observed in ride rate. A faster (.25 to .77 #/5) stride rate on the left occurred stages one, two, and three, and on the right in stage four (.60 #75). e males had longer running cycles (14.56 cm), stride lengths (6.97 ), stride times (.027 s), and slower stride rates (.49 #ls) than the males. During the subject selection from among the children enrolled in e Early Childhood Motor Development Program (E.C.P.) in the School of alth Education, Counseling Psychology, and Human Performance at chigan State University, the children were timed as well as classified 100 'abl e 8 lnal ysi s for Stage Effect on Selected Right and Left Leg Running We STAGE F n 1 2 3 4 (6,2) Rtbifltfi CYCLE (cm) 1.337 .4871 R1818 81.680 101.490 132.930 171.380 LEFT 75. 170 98. 990 127.670 169. 220 STRIDE LENGTH (cm) 1.170 .5287 RIGHT 42.700 54.670 70.000 83.900 EFT 39.450 46.960 67.930 87.500 STRIDE RATE (Us) 5.413 .1641 RIGHT 4.100 4.010 4.175 5.050 LEFT 4.350 4.780 4.815 4.445 58?le TIME (5) 9.022 .1031 R1810 0.245 0.250 0.240 0.200 LEFT 0.235 0.215 0.215 0.225 101 Table 9 Analysis for Gender Effect on Selected Right and Left Leg Running Measurements. some: F n 1qu rows 12,2) masons one 1:.) 0.297 .7708 men 125.940 114.900 LEFT 125.250 110.230 STRIDE LENGTH in) 0.470 .5955 RIEfT 64.559 61.050 151 14.427 55.995 ermine RATE w/s) 21.235 .0449 men 4.515 4.552 LEFT 4.102 5.042 5112102 me (5) 26.274 .0547 1211310 0.2513 0.250 LEFT 0.245 0.200 TU) 511 haI Fri Par atr Ear Dre 102 nto stages for running performance. The running velocities for the ubjects selected for filming were then calculated and analyzed along ith the running velocities obtained from the film to see if there might e any notable changes over the approximate 30 day period between ubject selection (April, 1986) and actual filming (May, 1986). Stage ne velocities were only available from the film since these two ubjects were too young for the E.C.P. program. Analysis of velocity easures yielded a significanct effect for stage (see Table 10). The unning velocities obtained in April showed stage four runners were ignificantly (p.0117) faster than stage two and stage three runners. be running velocities recorded in May were slightly faster (.06 to 69 s) than those in April, especially among the stage three runners. ay running velocities were statistically the same for stages two, hree, and four, and for stages one, two, and three. Stage one and four iffered significantly (p .0392). Considering the two different onditions under which the velocities for stage two, three, and four inners were obtained, it was encouraging that the velocities and ignificance levels were similar. Unfamiliar situations can sometimes ive an adverse effect on skill performance in the preschool child. 'om the two sets of running velocity data it appeared that this .rticular variable was not greatly affected by the unfamiliar mosphere of a human performance laboratory rather than the familiar C.P. gymnasium. The velocities obtained from the film are in agreement with the 'ly Childhood (1985) study and several other studies involving eschool age children (see Table 11). In addition, Fortney's (1980) 103 1ble 10 ialysis of RunningiVelocity (m/s) from Subject Selection Testigg April) and from Film (Malt. smoe 1 2 5 4 sensor seecriou not 2.155 2.149 5.917 F = 84.70 p=.0117 TESTING available _ 12.2) Fth 1.494 2.191. 2.859 4.017 F = 11.15 p=.0592 15,51 104 Table 11 Comparison of Running Speeds (m/s) by Developmental Stage and Age from Selected Research ((n) = Number of Subjects). STUDY AND SUBJECT CATEEIRIZATIDN DEVEIDPT‘ETRAL STAGES 1 2 3 4 Early Childhood (1985) 1.990 (11) 2.714 (308) 3.103 (576) 3.405 (287) Kiger (1987) 1.696 (2) 2.196 (2) 2.859 (2) 4.017 (2) H 111 YEARS 2 4 6 Fortney (1980) 2.133 (6) 3.750 (12) 4.263 (10) Mersereau (1974) 1.938 (4) Miyamaru (1976) 2.470 (6) 3.665 (20) 4.270 (10) 3 5 2.945 (18) 4.105 (15) 105 'unning indices for her 2-, 4-, and 6-year old subjects provided some .nteresting comparisons to the four developmental stages of runners in :he present study. In the three indices compared in Table 12 (speed/leg .ength, speed/stature, and mean step length) Fortney’s (1980) 2-year jlds differed significantly from her 4- and 6—year olds. Although the :wo studies cannot be directly compared (age level versus developmental stage level)J it is noteworthy that the indices for the 2~year olds are ilmost identical to those calculated for the stage two runners from the iresent study, and the indices for the 4-and 6—year olds are almost .dentical to those of the stage four runners of the present study. One question emerges. How much of the significance in previous ige level studies might have been due to the skill pattern used in 'elation to the age of the performer? The degree of relationship among a selected number of variables was f interest to this researcher. Several of the running descriptors were orrelated to observe their relationship among the running stages. hese correlations are presented in Table 13. In light of the ignificance found in trochanteric height and not total leg length, orrelations were run for both variables and stride length, stride rate, nd running velocity. The highest correlations were obtained for mean tride length versus running velocity (.97) and trochanteric height ersus running velocity (.83). Trochanteric height correlated higher van total leg length with stride length and running speed, whereas ital leg length correlated higher than trochanteric height with stride ite. Again it is difficult to discern why the higher correlations )peared for trochanteric height versus total leg length or vice versa, 106 Table 12 Running Indices by Age (Fortney, 1980) Compared to Running Indices by Stage (Kiger,l987). AK -STA8E (Mar of subjects tested in each category) Speed/Leg Length (aisle) Age in Years 2 4 6 5.981 (6) 8.326 (12) 8.330 (10) Stage 1 2 3 4 5.725 (2) 5.505 (2) 7.051 (2) 8.963 (2) Speed/Stature (o/s/I) Age in Years 2 4 6 2.373 (6) 3.479 (12) 3.572 (10) Stage 1 2 3 4 2.088 (2) 2.477 (2) 2.920 (2) 3.761 (2) Mean Step Length (I) Age in Years 2 4 6 .563 (6) .940 (12) 1.167 (10) Stage 1 2 3 4 .410 (2) .508 (2) .664 (2) .857 (2) 107 le 13 relations for Selected Running Descriptors. CDTdiflATED FEASLREMTENTS R Mean Stride Length (Cl) vs Mean Stride Rate (4/5) 0.2427 Mean Stride Length (cm) vs Running Velocity (:15) 0.9698 Stride Rate (l/s) vs Running Velocity (Ils) 0.4583 Trochanteric Height (cl) vs Stride Length (co) 0.7815 Total Leg Length (cm) vs Stride Length (co) 0.6007 Trochanteric Height (co) vs RUnning Velocity (nls) 0.8263 Total Leg Length (ca) vs Running Velocity (a/s) 0.7275 Trochanteric Height (cm) vs Stride Rate (4/5) 0.5284 Total Leg Length (cu) vs Stride Rate (8/5) 0.7548 108 ess the small number of subjects in the study affected these factors. zse correlation results reinforce the need to include both measures in ure research to ascertain the value of the current findings. mental Inclinations Segmental inclinations for the legs were investigated at four nts during one running cycle for each leg: touchdown of the foot to chdown of the same foot. During the drive interval, measurements e initially evaluated at touchdown and takeoff with maximum leg ension added when the data indicated this particular event occurred ore takeoff in most of the subjects. Trunk inclination was also luated at touchdown and takeoff. During the recovery interval surements were evaluated at minimum knee angle and maximum thigh ment height. Arm segment inclinations were evaluated at humerus imum forward swing and maximum backward swing positions. elopmental trend predictions were based on tracings made from earch films by Seefeldt et al. (1972) and Seefeldt and Haubenstricker 32). See Figures 1 through 6 (pp. 17, 19-21, 23-24). All linations were measured from the distal end of the segment, relative :he horizontal. Leg Drive Interval - Touchdown. During the drive interval elopmental trends for the leg segment inclinations at touchdown were )icted based on Figure 1 (p. 17). The greater the magnitude of the )h and shank segment inclinations the more forward (relative to the 109 ownward vertical projection of the body’s center of gravity) was the osition of the leg at touchdown. The greater the magnitude of the foot egment inclination the more the foot was dorsiflexed relative to the upporting surface. For the thigh segment at touchdown it was predicted hat the inclination would decrease from stage one to stage two, ncrease from stage two to stage three, and decrease from stage three to tage four. Data analysis of the subjects depicted in Figure 24 showed hat from stage one to stage two the left thigh followed the prediction nd the right thigh did not follow the prediction. From stage two to tage three both thighs decreased as opposed to the predicted increase n inclination. From stage three to stage four both thighs increased as pposed to the predicted decrease in inclination. For the shank at ouchdown it was predicted that the inclination would increase from tage one to stage two, then progressively decrease at stages three and our. The data indicated the left shank progressively increased from tage one to stage three then decreased from stage three to stage four. be right shank inclination decreased from stage one to stage two, ncreased from stage two to stage three and then decreased from stage hree to stage four. The foot segment at touchdown was predicted to follow the same ends as the shank; increased inclination from stage one to stage two, en progressive decreased at stages three and four. The data showed at both feet did increase in inclination from stage one to stage two. on stage two to stage three the right foot continued to increase while e left foot decreased in inclination. From stage three to stage four e right foot decreased in inclination whereas the left foot increased FEMALE HALE - FEMALE MALE ~ 5190551; 110 wwmmas W“2544 wmmams ““1145 STAGE Film tracings of subjects at right and left touchdown. ane thr sta C8111 10191 111 in inclination. The right—left differences for each segment were interesting. The left thigh inclinations were greater (2.82°) than the right thigh inclinations at stage one and the right thigh inclinations were greater (5.06°to 10.19°) than the left thigh inclinations at stages two (10.19”), three (8.51°), and four (5.06"). The right shank inclinations were greater (6.13”) than the left shank inclinations at stage one and the left shank inclinations were greater than the right shank inclinations at stages two (1.75°), three (0.34’), and four (7.79°). Right foot inclinations were greater than left foot inclinations at stages one (11.48°) and three (14.13°). Left foot inclinations were greater than right foot inclinations at stages two (2.27°) and four (3.57°). The only statistical significance (p.0319) obtained in the analysis was in the position of the right shank. Stage one, two, and three were statistically the same and stage two, three, and four were statistically the same. P values for the other segment inclinations at touchdown were .6914 for the thigh and .4799 for the foot (see Table F-1). P values for differences in leg segmental inclinations at touchdown between boys and girls in this study ranged from .2259 to .3245 (see Table F—2). However, females had greater (0.83° to 10.78°) thigh, shank, and foot inclinations than males for both the right and left legs. The combination of lower magnitude thigh inclination and higher magnitude shank inclination indicates that the limb touches down farther in front of the downward vertical projection of the body‘s center of gravity than the limb with a combination of higher thigh and lower shank inclination. The finding of the lowest shank inclinations 112 (83.62°, 91.4l°) in the stage four runners may indicate a parallel of the research reported by Dillman (1975) and wickstrom (1983). They indicated that the more mature and faster runner has a more efficient sequential backward rotation (with respect to the trunk) of the leg just prior to touchdown and has touchdown of the foot closer to the downward vertical projection of the body’s center of gravity. The distance between the downward vertical projection of the body's center of gravity and the foot at touchdown will be discussed in more detail later in this chapter. Leg Drive Interval — Takeoff. At takeoff, smaller magnitudes of segmental inclinations indicated greater backward extension of the thigh and shank segments and greater plantar flexion of the foot. Predicted trends for leg segmental inclinations at takeoff were based on Figure 2 (p. 19). Analysis of the subjects in this study (see Figure 25) yielded range of p values from .2191 to .7788 among the four stages and etween gender groups and some interesting variations on the predicted rends (see Tables F-3 and F-4). The thigh inclination at takeoff was redicted to decrease from stage one to stage two, which did occur in he subjects' left thighs but not in the right thighs. From stage two 0 stage three the thigh inclination was predicted to increase, but both ight and left thigh inclinations decreased in the subjects studied. rom stage three to stage four the thigh segment was predicted to ecrease, which did occur in the subjects’ left thighs but not in the ight thighs. In stages two and four the right thigh inclinations were reater (4.84°, 4.42°) than the left thigh inclinations, whereas in 11419 8 2 212424 .42 0124 as 2421 STAGE Figure 25. Film tracings of subjects at right and left takeoff. stages one and three the left thigh inclinations were greater (13.18°, 4.81°) than the right thigh inclinations. For the shank at takeoff, inclination was predicted to decrease from stage one to stage two, then increase from stage two to stage three. The subjects in the study did follow these predictions. From stage three to stage four the shank inclination was predicted to ecrease, which did occur in the subjects' right shank inclinations, but at in the left shank inclinations. The difference in the magnitude of he inclinations between right and left shanks was just the opposite of he thigh inclinations. At stage one and three the right shank inclinations were greater (3.71“, 2.33°) than the left shank inclinations, whereas at stages two and four the left shank inclinations vere greater (3.96°, 10.65°) than the right shank inclinations. The leg vith the combination of lower thigh inclination and higher shank nclination (as compared to the opposing leg) had greater (7.15° to 6.88°) actual knee angle (shank inclination + (180° - thigh nclination)) than the leg with a combination of higher thigh nclination and lower shank inclination. Foot inclination at takeoff was predicted to decrease progressively rom stage one to stage three then increase from stage three to stage our. Just the opposite occurred for both feet. Foot inclinations rogressively increased from stages one to three then decreased from tages three to four. At takeoff, both boys and girls had greater 3.50°, 0.86°) inclinations with the left thighs than the right thighs, at greater right than left inclinations for the shank (2.00', 6.29°) 1d foot (11.50°, 8.18‘) segments. Similar to touchdown, the females 115 had greater (0.7750 to 27.04°) inclinations of the leg segments than the males at takeoff. Leg Drive Interval - Maximum LegiExtension. Research on mature running form generally agrees that in most instances maximum leg extension occurs as the foot leaves the ground at takeoff. Research on the development of running described increases in leg extension at takeoff as age (and speed) increased (Clause, 1959; Dittmer, 1962; Fortney, 1980; and Miyamaru, 1976). The subjects in the present study varied somewhat from the reported trends. Actual maximum leg extension was determined by calculating the greatest knee joint angle: shank inclination + (180° - thigh inclination). The greatest knee joint angle did occur prior to, but increasingly closer to, takeoff as stage increased: stage one = .09 seconds, stage two = .05 seconds, stage three = .02 seconds, stage four = .01 seconds. (See section on temporal analysis for further discussion on this point.) Simultaneous maximum leg extension and takeoff occurred only on the right takeoff for stage three male and left takeoff for both stage four runners. At actual maximum leg extension both right and left leg segmental inclinations progressively decreased as expected, yet the actual knee joint angle progressively decreased (see Figure 26 and Tables F-S and F-6). Males had lower (3.14'to 14.34°) segmental inclinations than emales, but the females had greater (right = l.32°, left = 13.07°) ctual knee angles. Only the inclinations of the left shanks ignificantly differed (p.0306) between gender groups. Generally both ight and left leg segmental inclinations continued to decrease from FEMALE — RIGHT MALE - RIGHT FEMALE — LEFT HALE - LEFT STAGE Figure 26. Film tracings of subjects at right and left maximum leg extension. 117 maximum leg extension to takeoff, but the progressive linear trend among stages for decrease in actual knee joint angle is not present at takeoff as it is at maximum leg extension (see Table 14). Calculation of the actual hip joint angle (trunk inclination + (180° - thigh inclination)) revealed just the opposite trend. Each successive stage resulted in an increase in hip joint angle at takeoff, but this did not coincide with maximum leg extension. Calculation of the actual ankle joint angle (shank inclination + (180° - foot inclination)) revealed greater increases in the angle of plantar flexion between the instant of maximum leg extension and takeoff at stages one (35.64°) and two (25.94“) than stages three (13.18°) and four (13.08°). At maximum leg extension and takeoff the actual ankle angle decreased from stage one to three then increased at stage four. At maximum leg extension a linear trend of decreasing shank inclinations was observed for stages one through four in both the right and left leg segments. Whereas at takeoff, the shank segments decrease from stage one to two and increase from stage two to three. From stage three to four the right shank inclination decreases and the left shank inclination increases. A partial explanation for the observed differences in segmental inclinations, actual joint angles, and timing etween maximum leg extension and takeoff can be found in R. V. Mann’s (1981) kinetic analysis of sprinting. He reported that as takeoff was pproached, the knee extensors decreased in activity and thus provided rotection from hyperextension. The maximum extension of the leg may at occur as the foot leaves the ground at takeoff due to this decrease n knee extension activity. Since the timing for this decrease in knee 118 Table 14 Comparison of Mean Actual Leg Joint Angles (deg) at Maximum Leg Extension and Takeoff by Stage. STAGE 1 2 3 4 NIMOINT1 MXIMH LE8 EXTENSION 179.274 189.605 164.208 165.697 recon 184.296 189.853 194.951 196.443 IOEE JDINF 144111171 LE8 EXTENSION 181.552 173.014 170.982 162.936 TAKETFF 155.450 150.850 160.556 159.245 8101: JOINT= mxmun LE8 EXTENSION 101.092 96.503 95.66 120.984 TfIKEllCF 136.733 122.440 108.845 134.059 TOE LAPSE‘ .09 .05 .02 .01 1 Actual hip joint angle = trunk inclination 1‘ (180° - thigh inclination). 2 Actual knee joint angle = shank inclination + (180° - thigh inclination). 3 Actual ankle joint angle = shank inclination f (180° - foot inclination). 4 Tile (5) between maxim leg extension and takeoff. 119 extensor action depends upon the fine tuning of the nervous system, the degree of nervous system development then may be reflected in the observed and measured differences between maximum leg extension and and takeoff in these young children. The 100 fps film speed enabled the researcher to ‘see’ elements of the running cycle that occur too fast for the naked eye to substantiate. In this study, as the stage-one runners approached takeoff they seemed to "lockout" the support knee then ride their momentum forward. The knee of the takeoff support leg would ”give" as runners fell onto the opposite leg for support. Even with the addition of the flight phase in stage two, the subjects' extending support leg seemed to cease extension, then they would ride their momentum into flight rather than time maximum plantar flexion for a final push at takeoff. The final push off seemed more evident in stages three and four. These observations suggest questions for future investigation. Where does the extension of the leg segments cease in relation to takeoff? How does the amount and timing of extension relate to neurological development? A kinetic analysis would provide additional insight into these questions. Trunk Inclination at Touchdown and Takeoff. Trunk inclinations were measured relative to the horizontal as illustrated in Figure 17 (p. 86). The greater the magnitude of the inclination the more upright the trunk position. Statistical analysis of the trunk inclinations at right and left touchdown and takeoff yielded p values ranging from .0808 to .7403 among the four stages and between gender groups (see Tables F-7 and F-B). The inclination values were so similar among the four stages (<4.6°) that one cannot readily see any developmental trend. At touchdown (Figure 24, p. 110) all runners had lower (1.54° to 3.40°) inclinations (i.e. meaning slightly more forward trunk lean) on the right leg than on the left leg. At takeoff (Figure 25, p. 113) the stage two and stage three runners continued to have lower (0.65°, 3.06°) inclinations on the right leg than on the left leg with just the opposite true for stage one (3.58°) and stage four (l.68°) runners. At takeoff, the trunk inclinations for stage one runners were slightly more (1.31°) forward than at touchdown. Trunk inclinations for stage three performers were slightly more (1.58°) forward at touchdown than at takeoff. Stage two and stage four runners had slightly more (l.06°, 2.83°) forward trunk inclination at right touchdown than at right takeoff with the opposite occurring on the left leg (1.26°, 2.25°). Females had slightly more (4.00°, 4.l7°) forward trunk inclinations than males at both touchdown and takeoff. Both males and females had slightly more (2.49°, 2.60°) forward trunk inclinations at right than left touchdown, with the opposite true at takeoff (0.40°, 0.36°). Trunk inclinations among the subjects were comparable to those reported by Miyamaru (1976) and with the preschool-age children in Brown's (1978) study. Leg Recovery Interval — Minimum Knee Angle. Developmental trends for thigh and shank segmental inclinations during the recovery interval at minimum knee angle were predicted based on Figure 3 (p. 20). Trends for the foot-segment inclinations were not predicted. Analysis of the 121 data on subjects in Figure 27 yielded a range of p values from .0266 to .7361 (follow up test for p<.05 were nonsignificant) among the stages and between the gender groups (Tables F-9 and F-10). The larger the value of the thigh inclination, the higher was the position of the thigh relative to the supporting surface. The lower the value of the shank inclination, the closer the foot was positioned to the buttock. Whether the value of the foot inclination indicated plantorflexion or dorsiflection depended upon the foot inclination's relation to the shank inclination. Actual knee joint angle was calculated by using the formula of shank inclination + (180° - thigh inclination). The thigh segment inclination at minimum knee angle was predicted to decrease progressively from stage one to three, then to increase from stage three to four. The right thigh followed this prediction, but the left thigh inclination decreased from stage one to stage two then progressively increased from stage two to stage four. Shank inclinations at minimum knee angle also were predicted to decrease progressively from stages one to three then to increase from stage three to four. The right shank followed this prediction with the stage four inclination lower (18.30°) than the stage-one inclination. The left shank decreased from stage one to stage two, increased from stage two to stage three, then decreased from stage three to stage four. gain the shank inclination at stage four was lower (18.22°) than the bank inclination at stage one. Specific predictions were not made for foot inclinations at minimum :nee angle. From stage one to stage two both right and left-foot nclinations at minimum knee angle decreased. From stage two to stage 122 k 3" MALE - RIGHT g 1? Figure 27. Film tracings of subjects at right and left minimum knee angle. 123 three the right foot inclination continued to decrease while the left foot inclination increased. The opposite change occurred from stage three to stage four in that the right foot inclination increased and the left foot inclination decreased. The actual knee joint angle in the right leg followed a progressive linear developmental trend from stage one to stage four. The actual left knee angle progressively increased from stage one to stage three then decreased at stage four to a smaller (14.70°) angle than the stage one runners’ actual left knee joint angle. For both boys and girls there was a developmental trend of a decreasing actual minimum knee joint angle. However, at minimum knee angle, the males had greater (9.56° to 23.75°) thigh, shank, and foot segmental inclinations than the females. Right leg segmental inclinations were greater (2.98° to 9.06°) than left leg inclinations 3or the females, but for the males the right thigh and the left shank Lfld foot inclinations were greater (2.99° to 5.52°) than the left thigh nd right shank and foot inclinations. The actual minimum knee angle as smaller (1.59°, 8.27°) in females than males and the actual minimum nee angle for the right leg was smaller (1.80°) than the actual minimum Tee angle for the left leg. This overall developmental trend of an Icreasingly smaller actual minimum knee joint angle is in agreement th the previously reported research (Clouse, 1959; Dittmer, 1962; rtney, 1964; Glassow et al., 1965; Miyamaru, 1976; Brown, 1978; and 'tney, 1980). Although the segmental inclination measurements at minimum knee le were not statistically significant, it is of note that there were 124 right-left differences particularly in the shank and foot segments of the stage two and three runners. (See Table F-9.) Right-left differences in the shank and foot segments of the stage one and stage four runners were as much as 17 degrees less than those of the stage two and three runners. Right-left difference in thigh inclinations was approximately 20 degrees in stage two runners and less than four degrees among the stage one, three, and four runners. Leg Recovery Interval - Maximum Thigh Segment Height. The predicted developmental trend for maximum thigh segment height was based on Figure 4 (p. 21). The larger the inclination value for the thigh segment, the higher the runner was lifting the leg. Analysis of the data from the subjects shown in Figure 28 is presented in Tables F—11 and F-12. Statistical analysis yielded p values of .6856 to .9734 among the four stages and between gender groups. However, a developmental trend was evident. It was predicted that the thigh segment relative to the horizontal (measured from the distal end) would decrease from stage one through tage three, then increase from stage three to stage four. The data evealed this trend was followed by the subjects in this study. The high segment inclinations of the stage four runners were greater 1.39°, B.10°) than those of the stage one runners. At stages one and wo the runners had slightly greater (3.39°, 1.21°) thigh inclinations or their right thighs than their left thighs. The opposite occurred in he stage three and stage four runners (1.51°, 3.32°). The trend of ncreased thigh segment inclination between stages one and four and FEMALE - RIGHT MALE - RIGHT FEMALE - LEFT MALE - LEFT STAGE Figure 28. Film tracings of subjects at right and left maximum thigh segment height. 126 three and four is in agreement with the reported literature (Clouse, 1959; Fortney, 1964; Glassow et al., 1965; Miyamaru, 1976; and Brown, 1978). Specific predictions for the shank and foot segments at maximum thigh segment height were not made, but the data are interesting. The right shank and foot segment inclinations at maximum thigh segment height increased from stage one to stage two, decreased from stage two to stage three, then increased from stage three to stage four. Magnitudes of the stage four right shank and foot inclinations were greater (12.26°, 18.99°) than those in stage one. The opposite of this pattern was observed in the left shank and foot in that the stage four inclination were less (3.90°, 0.09°) than that in stage one. Left foot inclinations at maximum thigh segment height progressively increased from stage one to stage three, then decreased to the same degree as stage one. Although not statistically different, gender differences were evident. Thigh and foot segment inclinations for the males were greater ( 4.39° to 20.94°) than those in females. No trends were found for degrees of shank inclinations. The males had greater (10.160) inclinations in the left shank than in the right, and the females had greater (6.49°) inclinations in the right shank than in the left. Left- right differences in the thigh segments were less than one degree for both genders. Left-right differences in foot segment inclinations were Qreater in males (7.30°) than females (4.12°). Arm Segment Inclinations. Humerus and forearm inclinations were measured from the distal end of the segment, counterclockwise relative to the horizontal at the maximum forward and backward positions of the humerus (see Figure 21, p. 90). Predictions for the humerus and forearm 'nclinations at maximum forward position were based on the film tracings 'n Figure 5 (p. 23). At the maximum forward position the inclination of he humerus was predicted to decrease progressively from stage one to tage three, then increase from stage three to stage four. The left umerus followed this prediction with the stage four inclination being reater (6.89 ) than that for the stage one runners. The degree of nclination of the right humerus did decrease from stage one to stage .wo, but then progressively increased in degree of inclination from tage two to stage four. The degree of inclination of the stage four umerus was slightly less (4.80 ) than that of stage one. The forearms t maximum forward position were predicted to decrease progressively in nclination from stage one to stage three then increase inclination from tage three to stage four. Both right and left forearms followed this rediction. Predictions for the humerus and forearm inclinations at maximum ackward position were based on the film tracings in Figure 6 (p. 24). the maximum backward position the inclinations of the humerus were edicted to decrease from stage one to stage two, to increase from age two to stage three, and to decrease from stage three to stage ur. Both the right and left humeri decreased progressively in clination from stage one to stage four. The forearm at maximum ckward position was predicted to decrease progressively from stage one 128 to stage four. The right forearms progressively decreased from stage one to stage three, then increased in inclination, but remained less (16.28°) than that in the stage two. The inclinations of the left forearms increased from stage one to stage two, decreased from stage two to stage three, then decreased but remained lower (2.69°) than the stage one inclination. This would be the expected trend considering the position and action of the humerus. Statistical analysis of the data yielded p values of .0018 to .5422 among the four stages with only the right forearm significant when the right humerus was in the maximum backward position (see Figures 29 and 30 and Table F-13). At maximum humerus backward position the right forearm inclinations of stages one and two were statistically different (p.0018) from those of stages two, three, and four. Among the stages, the range of humerus motion .decreased from stage one to stage two and three then increased at stage four. The range of stage four runners was greater (37.26°) than stage one runners. The stage two through stage four trend is in agreement with the findings of Miyamaru (1976). It is interesting to note the left-right differences in the humerus range of motion (3.12” to 20.00°) across stages (see Table F—13). From stage one the greater range shifts from right to left and back to right with the largest right-left differences in stage two (20.00‘) and three (19.37°). This pattern is reflective of what is happening with the umerus inclinations. That is, the greater the humerus range, the reater the magnitude of the humerus inclinations at the maximum forward osition and the maximum backward position. P values of .1889 to .9626 were obtained between gender groups. 129 8 8 a» x 8. 29 a 8828. STAGE Figure 29. Sagittal film tracings of subjects at right humerus maximum forward and maximum backward. FEMALE - FORWARD FEMALE - BACKWARD MALE - FORWARD MALE - BACKWARD .5 STAGE 1 2 3 Figure 30. Frontal film tracings of subjects at right humerus maximum forward and maximum backward. 131 Females had larger (13.03°, 11.49”) ranges of motion and smaller (2.29° to 13.58°) forearm inclinations at both the forward and backward positions (see Table F-14). These observations raise the question of when, during the development of running skill, does arm motion become less of a reaction to and more of a contribution to force production? A kinetic study of developmental stages of running is needed to answer this question. Also, might there be some better way, than that used in the present study, to quantitatively analyze the qualitative changes observed in arm movements? Body 8.8.8. - Foot Distance at Touchdown. Two previous studies on the development of running in children have investigated the distance between the downward vertical projection of the body’s center of gravity and the foot at touchdown (Dittmer, 1962; Mersereau, 1974). The analysis of this distance for the subjects in the present investigation, yielded p values of .6552 and .4156 among the running stages and between gender groups. However, the data provide some insight to the conflicting findings of the previous two studies (see Figure 31 and Tables F-15 and F-16). Note the data are presented as actual measurements (cm), and as percent of standing height. From stage one to stage two the distance between the downward vertical Projection of the body’s center distance for the left foot of stage one runners was less (10% standing height) than for the right foot, with the opposite true for stage two (22 standing height), three (12 standing height), and four (3X standing height) runners. Males placed the right STAGE LIME Key: (1) = actual displaceaent in co (1) = percent of standing height L = left, R = right, H = huaerus, F = foreare Eigggg_§1. Distance between downward vertical projection of body center of gravity and foot at right and left touchdown. 133 foot closer (21 standing hieght) to the downward vertical projection of the body's center of gravity than the left foot, with the opposite (41 standing height) true for females. Keeping in mind that the developmental stages are age related, but not age dependent, the research by the Early Childhood Motor Skills Development Study (1985), Fountain, Ulrich, Seefeldt and Haubenstricker (1981), and Seefeldt and Haubenstricker (1982) gives evidence of the stage and age relationship in running development. Dittmer's (1962) subjects ranged in age from 5 to 11 years, an age span where the majority of the children are stage three and stage four runners. Mersereau’s (1974) subjects were 22 and 25 months old, an age span where children are generally stage one and stage two runners. Considering the age differences of the subjects in these two previous studies (Dittmer, 1962; Mersereau, 1974), the data reported in the developmental stage studies (Early Childhood, 1985; Fountain, Ulrich, Seefeldt and Haubenstricker, 1981), and the trend in the present study, the findings reported by Mersereau (1974) may not be the opposite of the findings reported by Dittmer (1962), but the two previous studies may be at opposite ends of a developmental trend. Further research is needed to verify the trend reported. Seguence of Peak Angular Velocity in the Leg,. Only one previous study of the development of running in young children investigated the sequence of peak angular velocities of leg action. Predictions for the present study were made based on Fortney's 134 (1980) data on limb joint peak angular velocities of 2-, 4—, and 6-year old children. The present study investigated the limb segment peak angular velocities of children ranging in age from 16 to 56 months who were categorized according to developmental stage of running skill. The reader is cautioned that a direct comparison between Fortney's (1980) results and those of the present study is not possible due to differences in the biomechanics software programs used in the two studies (Fortney, personal communication, April 14, 1987) as well as the difference in subject classification (age versus running stage). However, the two studies provide an interesting parallel. Drive interval. A thigh, shank, foot sequence of segment peak angular velocity was predicted for leg action during the midsupport and takeoff phases of the drive interval. This arrangement was selected since Fortney (1980) reported the majority of her 2-year olds had a simultaneous hip and knee, then ankle sequence, and the majority of her 4- and 6-year olds had a hip, knee, ankle succession of joint peak angular velocity. In the present study the stage one runners had thigh, shank, foot segment sequences except for the male’s left leg which sequenced shank, thigh, foot. The stage three and stage four runners had shank, thigh, foot segment sequences except for the stage three female‘s left leg which sequenced thigh, foot, shank. The stage two male had a shank, thigh, foot sequence of segment peak angular velocity, but the female had a right leg sequence of foot, thigh, shank and a left leg sequence of foot, shank, thigh. Several interesting observations can be made from the sequences reported in Table 15. Table 15 Seguence of Leo Segments Peak Angular Velocities for Leg Extension During the Drive Interval (ms = midsupport phase, to = takeoff phase). STARE GENDER RIGHT LE8 LEFT LE6 H thigh (to), shank (to), foot (to) shank (85), thigh (as), foot (to) 1 F thigh (as), shank (to), foot (to) thigh (as), shank and foot (to) II shank (as), thigh (to), foot (to) shank (as), thigh (as), foot (to) 2 F foot (as), thigh (as), shank (to) foot (as), shank (as), thigh (as) H wank (as), thigh (to), foot (to) shank (Is), thigh (to), foot (to) 3 F shank (as), thigh (to), foot (to) thigh (as), foot (as), shank (to) (1 shank (as), thigh (to), foot (to) shank (to), thigh (to), foot (to) 4 F shank (to), thigh (to), foot (to) shank (to), thigh (to), foot (to) 136 In the less mature runners, more of the leg segments peak during the midsupport phase of the drive interval whereas in the more mature runners, more leg segments peak during the takeoff phase of the drive interval. The sequence order seems to shift from thigh, shank, foot, in the immature running form of stage one, to shank, thigh, foot, in the mature running form of stage four. And, the greatest inconsistency in sequences is found in the stage two runners. Could these observations be reflective of neurophysiological developmental changes? Recovery Interval. A shank, thigh, foot sequence of segment peak angular velocity was predicted for leg action during the follow through and forward swing phases of the recovery interval. This arrangement was selected since Fortney (1980) reported the majority of all her subjects had a knee, hip, ankle sequence of joint peak angular velocity (see Table 16). In the present study all runners except the stage two male had a shank, thigh, foot sequence of segment peak angular velocity. The only other near variation was seen in the stage one female, whose foot segment velocity actually peaked during the foot descent phase. Two points are worthy of note here. The high speed of the film (100 fps) revealed the stage one female was beginning to move into the transition period between stage one and two (See section on temporal analysis for detail.). A question arises then. In qualitative assessment, both the stage one and stage two males were classic examples of their respective running development stages. The sequences of segment peak angular velocities for the stage one male were consistent for both legs whereas the sequences were inconsistent for the stage two male. Might the stage Table 16 Sequence of Leg Segments Peak Angular Velocities for Leg Flexion During the Recovery Interval (ft = follow through phase, fs = forward swing phase). STASE GENDER RIGHT LE8 LEFT LE8 H shank (f5), thigh (f5), foot (fs) shank (f5), thigh ((5), foot (fs) 1 F shank (f5), thigh (f5), foot (fdli shank (fs), thigh (f5), foot (fd)i h shank (fs), foot (fs), thigh (f5) foot ((5), shank (f5), thigh (fs) 2 F shank (f5), thigh (fs), foot (fs) shank (fs), thigh (fs), foot (f5) H shank (fs), thigh (fs), foot (fs) shank (fs), thigh (fs), foot (f5) 3 F shank (f5), thigh (fs), foot (fsl) shank (fs), thigh (f5), foot (f5) 8 shank (fs), thigh (fs), foot (fs) shank (ft), thigh (f5), foot (fs) 4 F shank (fs), thigh and foot (f5) shank (ft), thigh (f5), foot (fs) i Indicates actual peak angular velocity occurred during foot descent phase. one female‘s foot peak velocity occurring in the foot descent phase be a possible indication of her moving into the right-left inconsistency observed in the stage two male? A second point of note, since the stage two female, instead of having an inconsistent sequence of segment peak angular velocity, had the consistent right-left sequence found in the stage one male and the stage three and four runners. 8n the day of filming the stage two female ran in a stage three form during one of her trials, a common occurrence among children in transition between classic running stages. Might her consistency in segment sequence of peak angular velocity be an indication that she had begun the transition into a stage three running form? These questions can only be answered through further research on peak angular velocities in the developing FLITITIEF. Drawn Midline - Limb Segments Centers of Gravity Distance Previous research on running skill development has been almost entirely conducted from the sagittal plane (side view) and limited to leg action. In addition to the sagittal plane (side view) film analysis, the present study also used frontal plane (front view) film to explore an approach to investigating the rotary movements of the arms and legs about the vertical axis of the body. Four specific events within a complete running cycle for each leg were selected for analysis: touchdown, takeoff, minimum knee angle, and maximum thigh segment height. For each subject, the selected film frames were projected onto graph paper (10mm to a centimeter) in order to trace a stick figure of the subject's body position to be analyzed. A midline (determined by locating the midpoint between the two hip joints, then by drawing a line from, and perpendicular to, the supporting surface up through the midpoint between the hip joints, and continuing to equal head height, as illustrated in Figure 23, p. 93) was drawn over each stick figure. Using a Walton template (Walton, 1970), segmental centers of gravity were located and marked for each limb segment. The distance between each segment center of gravity, midpoint between the two shoulder joints, and the drawn midline was measured, multiplied by the film conversion factor, and then recorded for later statistical analysis. Data from the support and nonsupport sides of the body for the right and left touchdown, takeoff, minimum knee angle, and maximum thigh segment height were then analyzed. The statistical analysis a range of p values from .0755 to .9954 among the four stages and between gender groups. When the measurements are considered as a percentage of standing height, evidence of some possible developmental trends begin to appear among the four running stages. By comparing the right and left support side foot with the nonsupport side hand, as well as the nonsupport side foot with the support side hand, one can begin to see the rotary reactions of the limbs. At touchdown (Figure 32), several trends were apparent in the data (see Table F-17). Most obvious was that the support foot at right touchdown was closer (stage 1 = 2%, stage 2 = 5%, stage 4 = 2% standing height) to the drawn midline than the support foot at left touch down for all stages except three (12 standing height). The greatest (51 standing height) variation between support foot at left and right 140 RIGHT LEFT STAGE KEY:-————— = Support Side of the Body --------- = Nonsupport Side of the Body Figure 32. Frontal film stick figures for comparison of the distance between the drawn midline and the segment centers of gravity at right and left touchdown. 141 touchdown was in stage two. The support foot position in relation to the drawn midline did not show a trend over the four stages, but the opposing hand moved progressively closer (232 to 6.52 standing height) to the drawn midline across stages. The nonsupport foot moved closer to, then farther away (4.52 to 42 to 2.52 to 62 standing height) from the drawn midline across the stages while the opposing hand moved closer (342 to 14.52 standing height) to the drawn midline across the stages. The right touchdown nonsupport side hand was closer to the drawn midline than the left touchdown nonsupport side hand in all stages except stage two (right stage 1 = 102, stage 3 = 52, stage 4 = 42, left stage 2 = 32 standing height). The same, but opposite, overall pattern could be seen the in the nonsupport side feet and support side hands. At left touchdown the nonsupport leg seemed to be in position for greater outward rotation than the nonsupport leg at right touchdown for stages one, two, and three. Limb counterrotations seemed more symmetrical in stages one and four than stages two and three, but the limbs were much closer to the midline in stage four than the other three stages. Shoulder variation from the drawn midline, was toward the touchdown side of the body across all stages and was greatest (32 standing height) in stage three. The only item of note between gender groups was that females seemed to have slightly less (.0052 standing height) shoulder variation than males (see Table F-18). At takeoff (Figure 33), no real trend was noted in the support or nonsupport leg segments (see Table F-19). The hands moved closer to the drawn midline (support side = 262 to 52, nonsupport side = 312 to 132 standing height) across stages with greater variations (7 = 9.52 RIGHT LEFT STAGE KEY:——-———-= Support Side of the Body --------- = Nonsupport Side of the Body Eigure 33. Frontal film stick figures for comparison of the distance between—the drawn midline and the segment centers of grav1ty at right and left takeoff. standing height) on the nonsupport side in stages two and three than in stages one and four (2 = 4.52 standing height). No noticeable trends were observed between gender groups (see Table F-ZO). At minimum knee angle (Figure 34), the position of the nonsupport leg was observed to move closer (thigh = 112 to 42, shank = 132 to 52, foot = 122 to 12 standing height) to the drawn midline across stages indicating less outward rotation of the swing leg (see Table F—21). This decrease in outward rotation was evident in both right and left minimum knee angle and would agree with Nickstrom's (1983) observations. Again, no real differences were noted in the position of the support foot, and arm position moved closer (e.g. support side forearm = 242 to 152, nonsupport side forearm = 232 to 152 standing height) to the body across stages. As at touchdown and takeoff, there seemed to be slightly more right-left variability in stages two and three. The only point of note between boys and girls was that the support foot of the males was slightly closer (left = 12, right = 22 standing height) to the drawn midline than that of the females for both right and left minimum knee angle (see Table F-22). At maximum thigh segment height (Figure 35), the swing leg moved closer (thigh 7 = 8.52 to 5.52, shank Y = 102 to 4.52, foot 7 = 112 to 62 standing height) to the drawn midline and there was a reduction in foot flair (abduction) across stages (see Table F-23). The support side foot and arm moved closer (foot 7 4.52 to 32, hand 2 212 to 72 standing height) to the drawn midline across the stages. Between gender groups, the support and nonsupport foot were closer ($12 standing height) to the drawn midline at right maximum thigh segment height than at left maximum 144 RIGHT LEFT STAGE KEY: = Support Side of the Body .~'-~ = Nonsupport Side of the Body Figure 34. Frontal film stick figures for comparison of the distance between the drawn midline and the segment centers of gravity at right and left minimum knee angle. RIGHT "'Cbnltn LEFT “- unnunI-O‘ ' L— STAGE : Support Side of the Body — Nonsupport Side of the Body Figure 35. Frontal film stick figures for comparison of the distance between the drawn midline and the segment centers of gravity at right and left maximum thigh segment height. I46 thigh segment height except for males‘ support side where the left foot was closer (12 standing height) than the right (see Table F-24). Figures 36 and 37 offer a graphic illustration of the counter rotary action of the limbs at each of the selected events of touchdown, takeoff, minimum knee angle, and maximum thigh segment height. Position of limb segment centers of mass are indicated as if one were viewing the event from directly overhead the runner. Note that the changes in support foot position between touchdown and takeoff and minimum knee angle and maximum thigh segment height are due to the measurement method for determining the drawn midline location and thus reflects the amount of lateral shifting in the hips as the runner moved from one event to the next. Across all stages, the closer the foot was located to the drawn midline, the farther away was the opposing hand, but the distances decreased across the stages. As observed in the other variables within this study, there seemed to be greater left-right event variability in stage two and stage three runners than in stage one and stage four runners. Sagittal (side) and frontal (front) view analyses of paths of the total body center of gravity might give a clearer understanding than Single planar analysis of the development and refinement of running skill. Temporal Analysis. Based on previous research it was pFEdiCtEd that during one running cycle for each leg, the time in support would decrease while the time in flight would increase at each successive stage. This would also mean 147 ioucxnoux LEFT RIGHT (Support Side) (Non Support Side) STAGE (Non Support Side) (Support Side) 5 i 1 5 FT : MU A 6 UA H f F T HAU “ 1 FT TF ‘ UAH i s s : f '. I S f 2 S n : u A R 3 AA u : r K A ll ‘ 2F 5 T I SF 1 ‘ 1) AH : l S FST 1 11 HA 2 HA U f F T H A U ‘1 F S I T SF 3 ‘ U A H : : T i i T F5 : u A H l n A o : rs H A U " f F 5 IS F l ‘ U A : T i : : : i : : : : i : : f : : : 30 20 10 o no 20 30 3o 20 10 o (0 20 so LET TAKEOFF mam (Support Side) (Nan Support Side) STAG£ (Non Support Side) (Support Side) 5 : A : rr 1 u x 4 x A u : rsr m ‘isn n! ~ A A : : u : : S : : s r r : u A u x A A u : FT AHU *: r F ST .' ~ u A u : s i i r : S i 1 IF : u A x 2 H A u : mi A MU ‘: F FST :" U A )l l S f i i : : : TS r : u A H i H A u : rs T HA u o rs rs r u A x : r T : : : : : : i : : : : : ' : : 10 23 10 o [0 20 so so 20 10 o 10 20 .0 KEY: Limb segment location represented as a percentage of standing height. H = Hand, A = Forearm, U = Humerus, F = Foot, 5 = Shank, I = Thigh, ‘ = Shoulder Variation. Figure 36. Graphic illustration of ,eft touchdown and takeoff. limb segment locations for right and LEFT I48 HlNIHUH KNEE ANGLE RTEHT (Non Support Side) (Support Side) STAGE (Support Side) (Non Support Side) 5 T . TF T U A H A AU H TF TS H U TA FS T T F T " U H A T S T A 1 SF T U A H S k A U Tf S T H A U T " F T TSF‘ T U A H T S T T A T S T SF T U H 2 HA U T FT H A U T‘ FST F “ T U A ll T S T T T T T T SFT T U A H T H A U T TF5 H A U T‘ FT T SF ‘ T U A )l T S T T T T T T T T T T T T T T T 30 20 lo 0 TO 20 50 30 20 10 o 10 20 50 HT LEFT HAXTHUH THIGH SEBHENT HEIG RIGHT (Non Support Side) (Support Side) STAGE (Support Side) (Non Support Side) T l T T FS T A 4 U A H T S F HA U T“ FST T F ‘T US if T S T T T T T U A T T FS T All 3 U T SF AH U T ‘ T T SF ‘T U A N T F T T S T F ST T H HA 2 AM U T TS F H A U T" FST TSF A T U A H S T A T FT T )1 HA T H T T S F ‘1 A U T‘l FS T SF ‘T U A H T T T 30 20 10 0 To 20 30 30 20 )0 0 10 20 30 KEY: Limb segment location represented as a percentage of standing height. H=Hmd,A=FmeHy ‘ = Shoulder Variation. U = Humerus, F = Foot, 5 = Shank, T = Thigh, Figure 37. Graphic illustration of limb segment locations left minimum knee angle and maximum thigh segment height. for right and 149 the total time in support would decrease while total time in nonsupport would increase at each successive stage. Statistical analysis of this data in terms of time in seconds and as a percent of the total cycles for the subjects in the present study yielded p values ranging from .0390 to .0035 for stage effect and from .3384 to .8754 for gender effect (see Tables F-25 to F-32). P values (.05 were nonsignificant in follow up testing. The developmental trend across the stages observed in Tables F-25, F-26, F-29, and F-30 does follow the reported research (Beck, 1966; Brown, 1978; Dittmer, 1962; Glassow et al., 1965; Mersereau, 1974; Miyamaru, 1976; Smith, 1977; Vilchkovsky et al., 1973; and Wickstrom, 1983). Males spent more time in support (.015, .04s) and nonsupport (.355, .17s) on each side than females (Table F-27), but females spent slightly more time (.0025) in nonsupport than males (Table F-ZB). In terms of percentages, right—left differences for gender groups were mixed (Table F-31). Overall, males spent a greater (1.25) percent of the total right—left cycles in support than females and conversely, the females had a greater (2.75) percent of the total right- left cycles in nonsupport (Table F-32). Dne surprise and another possible explanation of an observed phenomenon emerged among the data. The surprise occurred in the stage one female runner. Two days prior to the filming, and during the filming session itself, she moved as a very highly motivated stage one runner with no visible flight. However, the film revealed .04 seconds Of flight in her run. This raised the question of how long must flight be before it becomes visible to the naked eye? One often observes an unevenness to the running of young children, 150 particularly those in stages two and three. A possible explanation for this unevenness becomes evident when one examines the temporal qualities of the run cycle for each leg. Taken as a total (both sides of the body and subjects for each stage averaged together), the developmental trend in support and nonsupport is smooth (see Figure 38). By separating the subjects within each stage the picture begins to change (see Figure 39). Females have less (19, 5) percent of cycles in support in stages one and four, where males have less (3, 16) percent in support in stages two and three. By further examining the percent of support and nonsupport for each leg of each subject at each stage, the picture becomes even clearer (Figure 40). In stages one and two there is noticeable difference in the percent of each leg cycle spent in support with males having greater (7, 4) percent in support on the left leg and females having greater (7, 5) percent support on the right leg. Although the difference is still observed in stages three and four, the magnitude of the variation is less (12 to 32) For both gender groups the left leg had greater (2) percent of support in stage three and the right leg has greater (2) percent of support in stage four. By examining the time breakdown for five selected periods within the cycle for each leg one can further inspect the variations. Table E-24 gives the time in seconds for each leg from: (a) touchdown to maximum leg extension, (b) maximum leg extension to takeoff, (c) takeoff to minimum knee angle, (d) minimum knee angle to maximum thigh segment height, and (e) maximum thigh segment height to touchdown. There were more occurrences of greater ().025) right-left variation in stage two than in the other three stages. A developmental trend can also be noted 151 STAGE 4 STAGE 3 STAGE 2 STAGE 1 0 20 40 60 80 100 PERCENT OF CYCLES _‘ = Support [:1 = Nonsupport Figure 38. Percent of total cycles in support and nonsupport by stage. -.s éu/ 54- 152 STAGE 4 n r STAGE 3 n F STAGE 2 H . F STAGE 1 M F 0 20 40 60 80 100 PERCENT OF CYCLES _ = Support :1 = Nonsupport Figure 39. Percent of total cycles in support and nonsupport by stage and gender. 153 STAGE 4 0 20 40 60 80 100 PERCENT OF CYCLES L FQEZLEJJ = Support E l = Nonsupport Figure 40. Percent of right and left cycles in support and nonsupport by stage and gender. 154 in the maximum leg extension to takeoff timing, which decreased as stage increased. Figure 41 illustrates the points of occurrence for the selected events for each leg for each subject represented as percent of the time for the combined cycles. The unevenness in the right-left leg cycles were more evident in the stage two runners. One must ask then, would further research involving greater numbers of children in each running stage reveal the same temporal variations? If the variations would prove common to the stage two runners, what is the relationship with the development of balance ability and neurophysiological maturation? Limb Segment Displacements Both linear displacement (centimeters) and angular displacement (radians and degrees) data for limb segment centers of mass were analyzed. The running cycle for each leg was divided into four periods for the analysis of leg segments displacement: 1 touchdown to takeoff, 2. takeoff to minimum knee angle, 3. minimum knee angle to maximum thigh segment height, and 4 maximum thigh segment height to touchdown. One forward—backward limb swing was analyzed for arm segments. Angular displacement values are tabled in both radians and degrees, however only the latter are included in the discussion and related figures. 155 STAGE 4 L A BC D E F F R A B C D E F \ L A BC D E F M R A B C D E F STAGE 3 L A B C D E F F R A B C D E F L A B C D E F M R A BC D E F STAGE 2 L A B C D E F F R A B C D E F L A B C D E F M R A B C D E F STAGE 1 L A B C D E F F R A B C D E F L A B C D E F M R A B C D E F 0 20 40 60 80 100 PERCENT OF CYCLES KEY: A = Touchdown D = Minimum Knee Angle B = Maximum Leg Extension E = Maximum Thigh Segment Height C = Takeoff F = Touchdown Figure j}: Point of occurrence for selected events within one running cycle for each leg by stage and gender. 156 Linear Displacement of Centers of Mass of Leg Segments. Analysis of linear displacements for centers of mass for leg segments yielded p values of .0638 to .8870 for stage effect and .0532 to .8853 for gender effect (see Tables F—33 and F-34). However, a graphic illustration of the data from Table F-33 provides further insight into the development of running skill (see Figure 42). Data are illustrated as actual measurement (cm), and as a percent of standing height. The period 1 portion of the graph (touchdown to takeoff) shows a nearly symmetrical configuration for each stage with stage two displaying some left—right limb segment variation. In the period 2 portion of the graph (takeoff to minimum knee angle) stages one, three, and four remained fairly symmetrical for right—left limb segment displacements with the most obvious right-left differences in stage two. In period 3 of the graph (minimum knee angle to maximum thigh segment height) stage one seemed to remained almost symmetrical. Stages two and three had greater (82 to 152 standing height) linear displacements of centers of mass of the left leg segments while stage four had greater (72 to 162 standing height) linear displacements of centers of mass of the right leg segments. In period 4 of the graph (maximum thigh segment height to touchdown), Fight-left linear displacements of centers of mass of leg segments appeared fairly symmetrical with slightly greater (42 to 182 standing haight) linear displacements of centers of mass for the right limb segments across all four stages. Again, the greatest (62 to 182 standing height) right-left variations occurred in stages two and three. Looking at the linear displacements of the centers of mass of the 199 segments in terms of a percent of standing height enables one to .amH comm L0+ w~u>u acaccsc mco mewcsu mycmEumm amH so mmme we mcmucmu +o Ayzufimc mcwucmum we acmucmu ucm suv «cmemumfiamwn mec«4 .Te mcmdim £35 A a ass " m .33 A a Jet . a £2 L .ugmmm; ucwucaum +o “caucus u A". .ucmamuufiamwu gasuum u «_L "sax 535...: 2 :2... 2...: 5:: .22.... . 2!; 2...; 5:: c 3 .::a ...; ::.E: n :95 :2 2:2... 2 :55. m .:szE SEE. . mafia . a. . _ _ . a. a . _ E; . a ma _ _ a a. ._ a N as; . .a . ma _ _ as L a a as; win a re a . as E a _ m _ I _ .21 _ I as .m as a _k. a .4 compare performance without considering any differences that might otherwise be reflected by stature differences among subjects. During period 1 the linear displacements for the centers of mass of the leg segments in terms of percent of standing height ranged from 262 to 472 for stage one, 262 to 502 for stage two, 182 to 392 for stage three, and 162 to 412 for stage four. During period 2 the linear displacements for the centers of mass of the leg segments in terms of percent of standing height ranged from 342 to 432 for stage one, 232 to 392 for stage two, 302 to 452 for stage three, and 522 to 662 for stage four. During period 3 the linear displacements for the centers of mass of the leg segments in terms of percent of standing height ranged from 112 to 262 for stage one, 202 to 532 for stage two, 242 to 532 for stage three, and 212 to 552 for stage four. During period 4 the linear displacement for the centers of mass of the leg segments in terms of percent of standing height ranged from 182 to 322 for stage one, 172 to 302 for stage two, 222 to 442 for stage three, and 252 to 322 for stage four. Through periods 1-3, stages two and four runners had a greater (132 to 342) range of linear displacements for the center of mass of the leg segments than stages one and three in terms of percent of standing height. During period 4, stages one and three had a greater (142, 222) ranges of linear displacements for the centers of mass of the leg segments than stages two (132) and four (72) in terms of percent of standing height. Between gender groups, in terms of both actual and percent of standing height (Table F-34), males had greater (12 to 132 linear displacements for the centers of mass of the leg segments than females during periods 1, 2, and 4. Females had greater (12 to 62) linear displacements for the centers of mass of the leg segments than males during period 3. The same general pattern was observed in the magnitude of right-left variations in linear displacements for centers of mass of the leg segments; right greater (02 to 72) than left for periods 1, 2, and 4 (except for males' left thighs were 12 to 22 greater than the right thighs in periods 1 and 2), and left greater (02 to 52) than right for period 3. Angular Displacement of Leg Segments. Analysis of angular displacements for leg segments yielded p values of .4823 to .9567 for stage effect and .1824 to .9951 for gender effect (see Tables F-35 and F-36). Figure 43 illustrates the angular displacements for each stage in Table F-35, which were measured from the distal end of the limb segment, counterclockwise relative to the horizontal. During period 1 (touchdown to takeoff) the thigh segment increased in angular displacement across stages while the shank segment decreased. The angular displacement of the foot segments increased from stages one to two, decreased from stages two to three and increased again from stages three to four. During period 2 (takeoff to minimum knee angle), angular displacement of the thigh segment decreased from stages one to two, then increased progressively from stages two to four. The angular displacement patterns for the shank were the opposite for the right and left segments. The right shank decreased, then increased, then decreased, where the left shank increased, then decreased, then increased in angular displacement across the stages. For stage two the left shank had greater (-21.21°) angular displacement than the right, .3: 5mm of EEG 055:: was 9:56 3:235 mm: to 33: ucmemummams 2235a .jmfiiu geese; 2.0 883:. Spas ate so: A a .:_: A s .235 A a .ass A m :82 A a "as a Ea as: 2%: seem :25 22:5: 3 toga A m sign 3 29a 35. SEE: A m _ P m ... _ p m ... mem xgzszg 83m zgmgzg Hz; msxozs «AHMAA as .6... . I o. . A ,. 5.862: 2 :83 2 cases A . 23m: 295% 5:: SEE A . L — m a Q N h m a u ._. m u N H m A_ 83m agxgxg 85m xgmuxq 35m ~3¢4m4 Show» 4&5 .o Asawfiw I .. .. . . . 0 .. . .. V V AC . o 1 I. .. I... m h m a m h m ... mmEm 14m4m4 82m ~3~3x4 an a.» 1 .T x.» w .Mv .. i v c h m ... ¢ _ m a . p m m 8.2% mgmgzg Wufim mgmgxq WEB mm «Magi Annwwo Aswan“ no. ... ... I . V . l. .om4 comm L0+ m4u>u oc4ccsc mco ocwczu mucmemmm mmH $0 .4cmemum4amwu Lo c044umu4u mm4mu4u:w geccc .4gowa A x .44m4 A 4 .50454 A a .4cmnm A m .4004 A a ”sax a4oc¢ mwcx 4:34AI 4caaoam ca452 e=e4c42 04 Laomxmh A m asacxwz as sauce sues asa_c_: A m LSOASAW o4 axocsasaL A exouzusob o4 4:04ax 4cmeamm 4m44H age4x~z A A 4 H m a _ _ m m _ H m m wu¢_m m 4 a 4 m 4 mochm x 4 m 4 m 4 mechm m 4 x 4 z 4 «fl 9 D k» A b «Aflqhd hwwn u ,Nww. u 1. a n u I; . a I .. .. ,l. mm. N 4 m a N a m a a 4 w a waqhm K 4 m 4 m 4 mochm m 4 z 4 x 4 macaw z 4 m 4 m 4 n«HWHD MUN? b ahflfififi l. .. . A . o .a . .A v V :0 A . It I. A. <2 m P m a m h m a mm¢4m m 4 x 4 x 4 um¢pm x 4 x 4 x 4 « A“ a w a. 4. x.» ..o [No .. .. av . a m a . a m a . a m a 425 2444 «4 sea as «414 am «was: Annowo spawn“ u I. .. x V .. lo. . ammu4 quEmum41m4n cmflamc¢ .n¢ mcamsm whereas in stage three the right shank had greater (~18.42°) angular displacement than the left. The magnitudes of the right~left shank differences are much smaller in stages one (-4.31°) and four (-9.99°). Angular displacements of the foot segments were different for each stage during period 2. For stages one and four the right foot dorsiflexed and the left foot plantar flexed. The angular displacement (disregarding direction) was greater (stage 1 = 51.62°, stage 4 = 0.51°) in the left foot than in the right. In stages two and three both feet plantar flexed with greater (-4.86°,-44.96°) angular displacements in stage three. The left foot had greater (-11.23°) angular displacement in stage two, whereas the right foot had greater (-28.75°) angular displacement in stage three. During period 3 (minimum knee angle to maximum thigh segment height), the right-left angular displacement patterns differed across the stages. The right thigh increased its angular displacement progressively from stages one to three, then decreased from three to four. The left thigh increased its angular displacement from stages one to two, then progressively decreased from stages two to four. The right shank and foot segments progressively increased in angular displacement from stages one to four, whereas the left shank and foot segments progressively increased in angular displacement from stages one to three, then decreased from stage three to four. Left shank and foot segments had greater (3.29°to 11.71°) angular displacements across stages one to three, whereas the right shank and foot segments had greater angular (13.44°, 13.82°) displacements in stage four. During period 4 the right-left limb angular displacement patterns 162 were different. The right thigh progressively decreased its angular displacement across the stages, whereas the left thigh progressively decreased its angular displacement from stages one to three then increased from stage three to four. The right shank and foot segments decreased, then increased, then decreased across the stages, whereas the left shank and foot segments increased, then decreased, then increased across the stages. Angular displacements for the right shank and foot segments were greater (5.80 to 27.59°) than those for the left shank and foot in stages two and four, but the opposite was true for stages three (left greater (31.02°, 42.94°) than right). For stage one the left- right angular displacements were mixed for the shank and foot segments. There were no evident trends for boys and girls except during period 3 (minimum knee angle to maximum thigh segment height). Here the females had greater (0.15° to 15.850) angular displacements than the males, but the right-left differences were mixed. Linear Displacement of Centers of Mass of Arm Segments. Humerus and forearm segments for each arm were evaluated from the maximum forward position of the humerus to its maximum backward position. Analysis of the linear displacement of centers of mass of arm segments data yielded p values of .7745 and .9373 for stage effect and .8908 and .9195 for gender effect (see Tables F-37 and F~38). Graphic illustration of the data in Table F-37 depicts the left-right variations observed for each stage presented as actual measure (cm) and as a percent of standing height (Figure 44). Greater (282, 332 standing height) linear displacements of the centers of mass of the left arm 163 STAGE r‘ h 3:! ”1:2'71 F-- STAGE Key: (1) = actual displacement, (T) = percent of standing height. L = left, R = right, H = humerus, F = forearm. Eiflflifi_ii, Linear displacement (cm and percent of standing height) of Centers of mass for humerus and forearm from humerus maximum forward position to humerus maximum backward position. 164 segments were particularly prominent in stage one. Stage two and four subjects also had greater (5% to 10% standing height) linear displacements of the centers of mass of the left arm segments whereas stage three subjects had greater (92 standing height) displacement of the center of mass of the right humerus. Males displayed greater (ll to 4% standing height) linear displacements of the centers of mass of right and left humerus segments than females. Linear displacements of the centers of mass for the left limb were greater (6% to 16% standing height) than those for the right limb for both boys and girls (see Table F-38). Angular Displacement of Arm Segments. Angular displacements of the humerus and forearm were evaluated from maximum forward position of the humerus to its maximum backward position, measured from the distal end of the segment, counterclockwise relative to the horizontal (see Figure 21, p. 90). Analysis of the data yielded p values of .0528 and .8698 for stage effect and .4476 and .6824 for gender effect (see Tables F~39 and F-40). Follow up tests revealed significant differences (p.0023) for angular displacement of the right forearm. Stage one differed from stages two, three, and four. Stages two and three differed from stages one and four. Stage four differed from stages one, two, and three. The right-left differences observed in the angular displacements of the centers of mass of the arm segments were even more striking than in their linear displacements (see Figure 45). In stage one, there was very little (-3.02°) difference in the left-right angular displacements of the humeri, but considerable (~40.74°) difference in the forearms. in mm 165 Key: H = humerus, F = forearm, L = left, R = right. Mow indicates direction of displacement. Note: Significance in right foreara.,1_ 3 _1, Figure 45. Angular displacement (deg) of humerus and forearm from humerus maximum forward position to humerus maximum backward position. In“ "EH 166 Stage two presents a mixture. The right forearm had greater (~45.07°) angular displacement than the right humerus, but the left humerus had greater (-7l.05°) angular displacement than the left forearm. In stage three, the left humerus had greater (~17.58°) angular displacement than the right humerus, but the forearm angular displacements were almost (0.59°) the same. In stage four, angular displacement was greater in the right humerus (-14.77°) and forearm (-33.05°) than in the left. Females had greater (-l.0°, ~12.74°) humeri angular displacements than males, but males had greater (-10.0l°, -16.22°) forearms angular displacements than females (Table F-40). Males had greater (-.081°, -20.51°) angular displacement in the right humerus and forearm than in the left whereas the females presented a mixture of results. For future research efforts, it might be interesting to attempt to assess the hand dominance of the subjects to determine if there is any relationship with the magnitudes of the angular and linear displacements of centers of mass of arm segments. Summary of Results This experimental interdisciplinary study used biomechanics research techniques to investigate the motor development stages (rather than age or grade common to previous research) for running in young children. Kinematic variables selected for investigation represented the distinguishing characteristics of the developmental stages of running according to Seefeldt et a1. (1972). The variables investigated were grouped into seven major categories: (a) running descriptors; fill an: 167 (b) segmental inclinations; (c) distance between the downward vertical projection of the body’s center of gravity and the foot at touchdown; (d) sequence of peak angular velocity for leg segments; (e) midline-limb segment center of gravity distance; (f) temporal analysis; and (g) limb segment displacements. Statistical significance (p$.05) was obtained for stage effect for mean trochanteric_height, running speed, right shank at touchdown, right forearm at humerus maximum backward position, angular displacement of right forearm, and for gender effect in the left shank at maximum leg extension. Since analysis of gender by stage groups could not be done due to the small number of subjects in the study, comment on the degree of any found or possible gender differences must wait for further research. However, of more notable importance were the developmental trends across the stages that were identified in almost all the areas of inquiry. By investigating action on both sides of the body (as opposed to single side analysis common among previous research) and then attempting to consolidate the multitude of variables analyzed, one gains intriguing insight into the intricacies underlying the qualitative characteristics previously identified for the developmental stages of running. Although symmetrical performance was not expected, diverse right-left variations were consistently observed among the data for stage two and stage three runners. Here again one must be somewhat cautious in that right-left differences range from less than one to as much as 10-20+ degrees, centimeters or percent of standing height. The data revealed two general patterns. These were left to right and thigh to shank relationship across stages and events. For example 168 in comparing right and left touchdown across stages, the leg with the combination of lower thigh segment inclination and higher shank segment inclination (see Table F-l) made contact with the supporting surface farther (1-82 of standing height) ahead of the downward vertical projection of the body's center of gravity (see Table F-15). The opposite combination (higher thigh segment inclination, lower shank segment) made contact closer (l-BZ standing height) to the downward vertical projection of the body‘s center of gravity. This combination held true across the stages and between gender groups. In the stage four runners the left leg made contact farther ahead (32 standing height) of the downward vertical projection of the body’s center of gravity than the right leg. This left-right, thigh-shank relationship was observed across events (touchdown, maximum leg extension, takeoff, minimum knee angle and maximum thigh segment height) for stage four runners. This same relationship was observed in stage two and three runners for touchdown, maximum leg extension, and takeoff and in stage one runners at touchdown, takeoff and maximum thigh segment height. A second right to left and thigh to shank relationship observed in stages one through three was that of the higher thigh to shank inclinations occurring in the same leg. This relationship was observed at maximum leg extension for stage one runners, minimum knee angle for stage one through three runners and at maximum thigh segment height for stage two and three runners. Evidence of the proximodistal deve10pment (Espenschade and Eckert, 1980, Haywood, 1986) is seen in the qualitative differences of limb action, but can be lost in the segmental approach to quantitative 169 analyses. The investigation of arm action in the present study was an example of this. Qualitatively there is considerable difference in what is happening in whole arm action (see Figures B-ll, pp 46-49), yet when segmentally measured from the sagittal plane (side view) the qualitative differences are much less evident. Expanding the way in which arm action is investigated, beyond the drawn midline-limb segment center of gravity distance measures attempted in the present study, would help more accurately quantify the observed qualitative differences in arm action. The developmental stages characterize differences in mechanical efficiency in the developing skill. The differing quantitative measures lend evidence to the identified qualitative differences across the stages. Yet the similarities in time and percent of support-nonsupport and magnitudes of obtained measures in linear (actual measurement in centimeters and percent of standing height) and angular (degrees and radians) displacements across stages give evidence of invariances within the developing skill. The degree of relationship among leg and arm measures of inclinations, displacements, and sequence of peak velocities (both linear and angular) for the develOping runner as opposed to the mature, adult runner, awaits further research. Inclusion of these variables in future research may help increase understanding of the relationship of neurophysiological maturation and sequential summation 0f the power train in motor skill development. Reflections on the Analyses Process. The traditional p<.05 level of significance was adhered to in this study. This researcher now questions the appropriateness of p<.05 to identify statistical significance in future research of this type. This belief is based on five factors: 1. the limited number of subjects, 2. the accepted qualitative differences in running form used across the stages, a. the developmental trends disclosed among the various individual quantitative measures, 4. the number of obtained p values between .05 and .20, and 5. the several places where p values of less than .05 occurred yet the location of statistical difference(s) could not be identified through follow up testing. Strictly adhering to the p<.05 level may be too stringent to flush out what is believed to be hidden significance, in the statistical sense, when research techniques and restrictions demand the use of a small number of subjects. In the present study evidence (as described above) of something happening (or about to happen) can be found in as many as 15 different stage effects and 11 different gender effects. (Again the reader is cautioned in respect to the potential of gender effects since stage by gender analyses were not possible in the present study.) In addition, since the identified qualitative characteristics distinguish points along a continuum of immature to mature skill form and since biomechanical research techniques are more likely to distinguish 171 extremes rather than gradations in performance (Ulibarri, personal communication, October 26, 1987), the suggestion that future researchers to consider a less stringent level of significance is strengthened, if indeed one desires to identify statistical differences in performance. For the present study, the types of information about the developmental stages and the obtained quantitative evidence to support the observed qualitative trends is of far greater importance to the understanding of skill development than whether a variable was statistically significant. Chapter V Conclusion and Recommendations This chapter contains two main sections. Concluding remarks and new questions arising from the present research will be presented in the first section. The second section will contain a series of recommendations for future research into the development of running skill in young children. Conclusion Previous research by physical educators specializing in motor development and developmental biomechanics has contributed greatly to the understanding of the development of fundamental motor skills, running particularly, in young children. The developmental biomechanics research has provided kinematic and kinetic information on position and movement of body segments and joints during skill performances by children of differing age or grade and gender (e.g. Fortney, 1980, Mersereau, 1977). The motor development research into developmental staging of motor skills has identified age related, but not age dependent, changes for key descriptive characteristics in developing fundamental motor skills in young children (e.g. Seefeldt et al, 1972). 172 173 These key descriptive characteristics in developing skills are generally synonymous to kinematic variables investigated by age or grade level in developmental biomechanics studies. Prior to the present study, biomechanical analysis of the identified developmental stages of various fundamental motor skills, as defined, had not been attempted. The present interdisciplinary study was therefore undertaken to explore the potential for using biomechanical research techniques, specifically high speed cinematography, to help determine the extent and significance of mechanical differences observed in developing running skill. Selected kinematic and anthropometric variables for the skill of running were investigated to define which specific variables, if any, differed among the four developmental stages as well as between the performance of boys and girls. Considering the research techniques used and previous research in developmental staging of motor skills, a very small number of subjects was selected for the present study with the understanding of the risks involved both from the standpoint of statistical analysis and the unpredictability of preschool age children. The variables investigated in the present study were categorized into seven major areas: (a) running descriptors (stride length, stride rate, stride time, cycle length, total right-left cycle distance, total right-left cycle time, running Speed, and selected anthropometric measures as they relate to running skill); (b) segmental inclinations at selected points during the running cycle; (c) distance between the downward vertical projection of the body‘s center of gravity and the foot at touchdown; (d) sequence of peak angular velocity for leg segments; (e) drawn midline-limb segment center of gravity distance at 174 selected points during the running cycle; (f) temporal analysis; and (g) limb segment displacements, both linear and angular. The variables were analyzed for each leg in order to observe differences between right and left limb actions. Two hypotheses were examined in this study: (a) each of the selected kinematic variables will follow the predicted trends, showing significant differences from stage to stage, in the running behavior of young children, and (b) there will be no statistical differences for each of the selected kinematic variables across stages between boys and girls. The results of this study fail to support the first hypothesis. Only five variables yielded statistical significance for stage effect, (trochanteric height, running speed, right shank at touchdown, right forearm at maximum humerus backward position, and angular displacement of the right forearm). Whether the lack of statistical significance for the other variables was due to the small number of subjects studied or to actual nonsignificance among the variables as they were measured can only be determined by further research using much larger numbers of subjects. However, many of the predicted trends were followed, developmental trends were present, and of the variables investigated, several items provided valuable insight into running skill development. The second hypothesis, that there will be no statistical differences between boys and girls across stages on each of the selected kinematic variables was not fully supported by the results of this study because a significant difference was indicated for the left shank at maximum leg extension. However, the reader is cautioned. The small number of subjects made it impossible to cross analyze variables by gender by stage. Before one can verify that no differences exists between gender groupss or among the stages additional research needs to be conducted with enough subjects to warrent stage by gender statistical analysis. The use of high speed cinematography not only allows the researcher to review, repeatedly, the skill performance of a child, it also reveals elements of the skill that are otherwise unobservable to the naked eye. No flight was observed in the skill performance of the stage one female until the film was first reviewed. The .04 seconds of flight present in her run immediately raised the question of how long must flight be before it is visible to the naked eye? A first hint as to the arrhythmical run often observed in stage two and three runners was also revealed through analysis of the film. Occasionally a child would not have flight on one side of the body. This observation raises the question at what point does the rhythmical quality of the run even out? Of particular note and interest were the consistently larger left- right limb variations among the variables studied in the stage two and stage three runners. The right-left variations were first revealed in the segmental inclinations data giving indication of a reason for the choppy run often observed in the children running in stage two and stage three. A further basis for this arrhythmical run became particularly apparent from the temporal analysis and linear and angular displacement data analysis. The larger right-left variations in stages two and three were also evident in the data analyzed from the frontal film (front view). Graphic illustrations (Figures 36 and 37, pp. 147-148) of the distance between the midline and limb segments centers of gravity 176 provided an interesting view of the development of the counterrotary reaction at the selected events during the running cycles for each leg. The researcher cannot help but wonder that if the drawn midline-limb segments’ center of gravity information were combined with linear and angular displacement data for both arms and legs, would it provide greater insight to the development of running skill in young children? Little research on the development of arm action in running has been attempted in the past. The present study investigated arm segment inclinations at maximum forward and maximum backward humeri positions as well as the linear and angular displacements between these two positions. In retrospect, and in light of the type of information obtained, the researcher believes it would have been more informative to analyze arm inclinations at the same positions leg inclinations were investigated. Likewise, analysis of arm linear and angular displacements during the same periods used for the angular and linear displacements of the leg segments analysis might have proven more informative. Then comparisons, similar to the one done for limb segments‘ center of gravity from the drawn midline could have been made. The observation of the results of the distance limb segments' center of gravity distance from the midline raised the question of when during the development of running skill does arm motion become less of a reaction to and more of a contribution to running? Although the data analyzed in the present study provided insight into the development of arm action, the researcher questions if there might be some other, more informative method of studying developing arm action in running? Both linear and angular displacement data were generated by 177 the biomechanics software program used by this researcher, each were analyzed for the subjects to determine which data might be more useful to motor development skill study. The linear and angular data analyses for the subjects studied provided fascinating insight into the development of the running skill. which displacement data would prove more useful to motor development will depend on what any one researcher is attempting to interpret. If the ultimate goal of this type of research is to help the preschool and elementary physical education teacher better understand and observe skill development and to plan more effective programs, then perhaps the angular displacement information might be more easily observed and interpreted by the teacher in the school gymnasium (especially for individuals with a limited background in physics and biomechanics). The timing and film observation of action from maximum leg extension to takeoff in the stage one and stage two runners studied raised some questions. Maximum leg extension occurred prior to takeoff in stages one and two. These runners seemed to achieve the maximum leg extension then ride their momentum onto the opposite leg or into flight. This observation raised the question of where does the actual extension of the leg segments during the drive interval cease in relation to takeoff? How do the amount and timing of extension and summation of power train relate to neurological development of the young runner? A kinetic analysis of the developmental stages of running would begin to provide insight into this observation? The research of Fortney (1980) and Mersereau (1974) provided much stimulation for this researcher's present effort. Among the variables Hersereau (1974) investigated with her 22— and 25-month-old girls was the distance between the downward vertical projection of the body center of gravity and support foot at touchdown. Since Mersereau's (1974) results (an increase in the distance from 22 months to 25 months in age) were opposite of those obtained by Dittmer (1965) (a decrease in distance as age increased from five to eleven years), this variable was included in the present study in an attempt to obtain a possible understanding of the conflicting results in the two previous studies. The findings of the present study suggest that the Mersereau (1974) and Dittmer (1965) results were not contrary, but at apposite ends of a developmental trend. In the present study the distance increased from stage one to stage two, then progressively decreased from stage two to stage four. Further research on this variable is needed to verify this developmental trend. A study of running skill development by age (2-, 4-, and 6-year olds) conducted by Fortney (1980), resulted in significant differences between the 2-year olds and the 4- and 6-year olds, but no differences between the 4- and 6-year-olds. Fortney (1980, personal communications, February 14, 1985 and April 14, 1987) raised the question of what might be happening to the running performance of 3- YEar-olds. Considering that developmental stages are age related, but not age dependent; that the mean age for stage two, stage three, and stage four runners are 2.5, 3.5, and 4.0-4.5 years, respectively (Early Childhood, 1985); and the comparison running indices by age and stage in Table 12 (p. 106) are similar, one might suggest that indeed something a, was happening in the running skill of a-year-olds. More research by 179 developmental stage, involving greater numbers of subjects is needed to answer the question raised by Fortney (1980, personal communications, February 14, 1985 and April 14, 1987) and to verify the findings of the present study. Despite the lack of statistical significance for stage effect, the researcher feels the present study did, indeed, reveal that the use of biomechanical research techniques to investigate the developmental stages of running will provide invaluable information and insight into skill development in young children. This motor development researcher echoes Garrett's (1978) expression of the promise of synergistic research efforts between motor deveIOpment and developmental biomechanics specialists. Recommendations Based on the experience gained and the results obtained from conducting the present study, the following recommendations are made: 1. If additional research is conducted on the developmental stages of running skill, it should be a cooperative, team effort involving at the least individuals specializing in developmental biomechanics and motor development. Individuals interested in motor learning, developmental psychology, developmental neurology, and developmental neurophysiology would also be valuable additions to a team approach to a study of running skill development. 2. A future study in skill development should contain enough subjects to permit statistically cross comparisons of limb side, gender, stage, 180 and age to obtain a more detailed understanding of skill development. Such cross comparisons would provide deeper insight into the developing skill. Perhaps more important, such comparisons may provide greater understanding of age versus stage changes in motor skill development. 3. Once the minimum number of subjects is ascertained to conduct the desired statistical analyses, select and film twice as many subjects, if possible. Preschool children are unpredictable in their behavior. Some may perform at, or above, expected skill stage and others may perform poorly when placed in the formal situation of data collection. Also, it is unknown when a child may move into transition between stages. Since one day may make a difference, longitudinal study of skill development in young children would be valuable. If extra subjects are filmed, the best possible representations of each developmental stage could be obtained in the quantities needed for statistical analysis. 4. Future studies should consider adding kinetic variables to the data analysis to obtain developmental information on these factors. The collection of data that requires technical equipment to be applied to the subject's body or to be crossed by the subject creates additional challenges in dealing with preschool age children. However, the potential of kinetic data for increasing the understanding of skill development would be well worth the effort if the expertise, equipment, and computer programming are available. 5. Future studies should investigate the path of the body’s center of gravity. Both horizontal and lateral oscillations should be investigated to determine differences among the developmental stages. One might also note the location of the bOdY'S center 0* gravity within 181 the runners performing at each stage and what effect this location (or the movement of) might have on the developing skill performance. 6. Future studies should investigate arm segment inclinations, velocities, and displacements at the same points and periods as leg segments to obtain a more detailed understanding of the total skill development. Likewise, investigate both right and left limbs to gain better understanding of developmental stage differences. 7. Future research should attempt to determine the subjects‘ ability to maintain states of static balance and dynamic control for right and left limbs to correlate with skill development data in an effort to determine to what degree, if significant relationships are evident between balance development and motor skill development. 8. Future research in motor skill development should continue to use multidimensional analysis using whatever state-of-the—art systems are available to the research team (e.g. Cellspot, Natsmark, optoelectric). Consideration should also be given to overhead and/or three dimensional analysis if such equipment and computer programming is available to the research team. 9. If at all possible, at least one member of the research team should be familiar with the subjects prior to the data collection. This researcher made an effort to visit the classes attended by the subjects and became familiar with the motor skill patterns used by the children in informal play situations. Although most of the children were familiar with the testing situation as conducted in the Early Childhood (1985) research, the filming situation was new. The more at ease the children are with the researcher(s) and the surroundings the 182 more likely they are to perform in their true developmental stage. Researchers not intending to collect force platform generated data might consider collecting data in‘a gymnasium more familiar to the children than the formality of a human performance laboratory (assuming proper lighting conditions are available for the system used for data gatherings). Consideration might also be given to the time of day the child is to be filmed in order to obtain the child's truest developmental stage performance. PPPPPPPPPPP APPENDIX A Early Childhood Motor Skills Development Study Tables on Running (able PErCEI Table A-1 Percent of Children Running at Various Stages by Age and Gender. ME IN EKDB (Mehikmfl 81E HERE 30-35 36-41 42-47 48-53 54-59 60F65 TOTALS TOTALS (2.5) (3.0) (3.5) (4.0) (4.5) (5.0) (Z) (N) (Z) (N) GENDER H F H F H F b F H F E F (N) (134) (124) (175) (166) (199) (125) (159) (118) (123) ( 68) ( 69) ( 34) (100)(859) (100)(635) STAGE 3.7 0.8 13.1 2.4 28.6 8.0 37.1 22.0 59.3 38.2 60.9 52.9 30.2 259 13.4 85 4 (a-) STAGE 39.6 34.7 54.3- 52.4 81,8_ 24,2; 48,4 88,8 82,8 48,4 28,8: 44,_: 45.2 388 53.7 341 3 (a-) (a) (a-) (a) (a) (af) (a) (af) STAEE 56.0+ 88,8 31.4 43.4f 19.6 20.8 14.5 14.4 8.1 13.2 10.1 5.9 24.3 209 31.3 199 2 (a+) (a) (afl STAGE 0.7 5 6 1.1 1.8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.3 3 1.6 10 l PRE- 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0.0 0 STAGE 5. D 0.6 0.6 0.7 0.6 0.7 0.5 0.7 0.6 0.6 0.7 0.7 0.6 ( a = The median stage for each age group. f or - indicates transition between stages. For example a+ indicates the median stage for 4.5 year old males is 3+. underlined numbers = The mean stage for that particular age. + or - indicate transition between stages. For example 43.4f indicates three year old females mean stage is 2+. Z ote: From The Early Childhood Motor Skills Development Study (1985). tandards of Performance on Selected Fundamental Motor Skills for Egeschool Age Children. Tabulated data. School of Health Education, (.0 Counseling Psychology, and Human Performance, Michigan State University, East Lansing, Michigan. (able Parcel Perfm 184 Table A-2 Percentile Ranks with Transitions Separated from Whole Stage Running Performance by Age and Gender. flfii AGE! 1- 1 1+/2- 2 2f/I- 3 3+/4* 4 MEDIAN S. D. HNMR W) (i (134) 1 l 40 70 92 98 100 2+ 1 1 25 F (124) 2 11 47 77 94 99 100 2+ 1 1 H (175) 1 3 21 45 80 93 100 2+l3- 1.2 30 F (166) 1 3 34 55 93 99 100 2+ 1 l H (199) 12 26 61 81 100 3 1.2 35 F (125) 1 14 32 79 97 100 3- 1.0 H (159) 9 21 53 79 100 3 1.2 L0 F (118) 1 11 23 67 B3 100 3 1.2 H (123) 5 10 31 54 100 3+ 1.1 45 F (6& 9 16 50 79 NM 3 L2 M ( 69) 3 10 33 61 100 3+ 1.1 50 F ( 34) 6 9 29 68 10 3fl4- 1.1 2 ate: From The Early Childhood Motor Skills Development Study (1985). andards of Performance on Selected Fundamental Motor Skills for eschool Age Children. Tabulated data. School of Health Education, Counseling Psychology, and Human Performance, Michigan State University, East Lansing, Michigan. U) I"? ( 'T.‘ ..., ( Table (H mm- M: Frog Standards (l ”(501% Counseling UMVersity’ 185 Table A-3 Mean 15-Yard (13.71 Meter) Run Times in Seconds and Speeds by Age and (lends;- 1481: GENDER 14 4 me 5. 0. 9mm 94140878280410 monsoon 11 107 5.71 1.30 8.67 2.63 2.40 2.5 r 98 5.56 1.18 7.79 2.70 2.46 I y 14 140 4.93 1.08 8.23 3.04 2.78 ' 3.0 F 134 5.15 1.03 6.81 2.91 2.66 14 165 4.41 0.78 5.01 3.40 3.11 3.5 r 98 4.59 0.74 4.31 3.27 2.99 11 124 4.12 0.64 3.93 3.04 3.33 4.0 F 98 4.32 0.73 4.12 3.47 3.17 14 97 3.90 0.48 2.84 3.85 3.51 4.5 r 52 3.93 0.54 2.91 3.82 3.49 14 54 3.71 0.47 2.03 4.04 3.69 5.0 r 25 3.73 0.31 1.25 4.02 3.17 Note: From The Early Childhood Motor Skills Development Study (1985). (D .Landards of Performance on Selected Fundamental Motor Skills for Egeschool Age Children. Tabulated data. School of Health Education, Counseling Psychology, and Human Performance. Michigan State University, East Lansing, Michigan. 2.5 M: FFOm Standar115 Counseling Ufllversity’ 186 Table A-4 Mean 30-Yard (27.42 Meter) Run Times in Seconds and Speeds by Age and weer..- ABE GENDER 11 1 THE 5. 11. R1481: YARDS/SECOND PETERS/$801111) 11 107 11.88 2.71 17.37 2.53 2.31 2.5 r 99 11.83 2.48 15.63 2.58 2.38 11 138 10.23 2.55 20.75 2.93 2.88 3.0 r 134 10.81 2.04 11.87 2.83 2.58 14 185 8.99 1.83 12.71 3.34 3.05 3.5 r 98 9.35 1.48 7.08 3.21 2.93 14 124 8.35 1.38 9.51 3.59 3.28 4.0 F 98 8.83 1.45 8.22 3.48 3.17 14 97 7.83 1.08 8.59 3.83 3.50 4.5 r 52 7.90 1.09 5.83 3.80 3.47 14 54 7.37 1.01 5.12 4.07 3.72 5.0 r 25 738 0.81 2 82 4 06 3 71 flggg; From The Early Childhood Motor Skills Development Study (1985). Standards of Perforgance on Selected Fundamental Motor Skills for Preschool Age Children. Tabulated data. School of Health Education, Counseling Psychology, and Human Performance, Michigan State University, East Lansing, Michigan. Table A-5 Percentile Ranks ’_____.__——— and Gender. ((51 8.64 f 15 7.70 H 97 9.09 F 52 9.511 (I (24 9.50 l 165 11.00 1 l Table A-5 Percentile Ranks for 30-Yard (27.43 Meter) Run Times in Seconds by Agg and Gender. 088/ (N) 10 20 25 40 50 60 70 80 90 100 fled. 8.0. H 54 Bid 7J0 7J5 7A5 L 04 H 7.02 6.79 6.66 6.48 5.88 7.30 1.01 50 F 25 7.70 7.81 7.80 7.64 7.43 7.29 7.07 6.90 6.77 5.87 7.40 0.61 H 97 9.09 8.48 8.27 7.99 7.77 7.56 7.32 6.95 6.68 6.06 7.71 1.06 L5 F 52 9.50 8.75 8.55 7.98 7.76 7.62 7.34 7.07 6.71 6.07 7.75 1.09 H 124 9.50 9.04 8.84 8.39 8.14 7.97 7.73 7.51 7.05 6.20 8.13 1.38 L0 F 98 10.40 9.56 9.29 8.70 8.51 8.17 7.97 7.66 7.07 6.33 8.49 1.45 H 165 11.00 10.10 9.86 9.26 8.94 8.46 8.03 7.60 7.24 5.85 8.91 1.63 35 ' F 98 11.42 10.56 10.25 9.59 9.14 8.60 8.35 8.15 7.85 6.80 9.12 1.48 H 138 12.17 11.18 10.96 10.02 9.76 9.40 9.09 8.84 8.20 6.31 9.73 2.55 F 134 13.60 11.90 11.19 10.49 10.25 9.90 9.62 9.23 8.60 7.54 10.20 2.04 H 107 14.70 13.42 13.17 11.98 11.47 10.96 10.39 9.94 9.01 6.82 11.43 2.71 25 F 99 14.44 12.80 12.50 11.96 11.51 10.80 10.28 9.92 8.90 7.13 11.46 2.48 Note: From The Early Childhood Motor Skills Development Study (1985). Standards of Performance on Selected Fundamental Motor Skills for Preschool Age Children. Tabulated data. School of Health Education, Counseling Psychology, and Human Performance, Michigan State University, East Lansing, Michigan. Table 1H: Mid—MIL” smaE 15E Continued on next page Table A-6 188 30-Yard Run Times in Seconds and Sneeds by StageJ Age, and Gender. STAGE 00E GENDER N x HEDIAN RANGE 0.0. 100/000 HISEC 4 5.0 n 33 7.04 7.00 2.05 0.04 4.20 3.09 E 14 7.17 7.13 2.02 0.05 4.10 3.02 4.5 n 57 7.57 7.50 3.92 0.92 3.90 3.02 E 21 7.39 7.10 3.59 0.95 4.00 3.71 4.0 n 40 7.04 7.02 3.27 0.79 3.03 3.50 E 23 7.54 7.04 3.14 0.00 3.90 3.04 3.5 n 52 0.20 7.97 5.95 3.02 3.31 E 9 0.75 0.15 3.00 3.43 3.13 3.0 u 20 0.07 0.01 4.49 . 0 3.10 E 4 9.47 9.90 2.40 . 3.17 2.09 2.5 n 5 9.25 0.70 0.24 2.34 3.24 2.90 F 1 0.50 0.50 - - 3.53 3.23 3 5.0 n 10 7.55 7.30 3.79 0.09 3.97 3.03 E 10 7.23 7.00 1.57 0.49 4.15 3.79 4.5 n 32 7.99 7.91 4.40 0.09 3.75 3.43 E 20 0.01 7.91 2.04 0.70 3.74 3.42 4.0 n 50 0.31 0.10 5.50 3.01 3.30 E 00 0.09 0.50 5.04 . 3.45 3.15 3.5 n 03 9.10 9.03 0.75 3.30 3.01 E 71 9.00 0.90 5.03 3.31 3.03 3.0 n 71 10.02 9.04 19.02 2.39 2.99 2.74 E 74 9.77 9.09 5.50 1.21 3.07 2.01 2.5 n 42 11.11 10.70 0.00 1.99 2.70 2.47 E 33 11.13 10.53 11.72 2.34 2.09 2.40 Continued on next page- Table A-6 Continued STAGE AGE 861 1 5.0 I' F 4.5 1' F 4.0 n F 3.5 44 F 3.0 H F 2.5 H F \ 1 5.0 H F 4.5 H F 4.0 H F 3.5 H F 3.0 H F 2.5 H F \ N0. 4. Table A-6 Continued. 189 01005 ASE GENDER N x MEDIAN RANGE 0.0. YDS/SEC H/SEC 2 5.0 n 2 9.00 0.04 4.09 1.09 3.33 3.05 E 1 7.70 0.04 — - 3.00 3.52 4.5 n 7 9.24 0.02 5.09 3.25 2.97 E 5 9.47 9.05 4.03 3.17 2.09 4.0 n 17 9.97 9.00 7.10 2.33 3.01 2.75 E 15 10.09 9.33 1 2.00 2.97 2.72 3.5 n 30 9.92 9.57 11.07 3.02 2.70 E 17 10.01 10.50 5.73 2.77 2.54 3.0 n 45 11.03 10.41 14.00 2.70 2.72 2.40 E 50 11.51 10.04 9.00 2.13 2.10 2.30 2.5 n 59 12.02 12.00 15.03 2.94 2.30 2.17 E 00 11.73 11.70 15.03 2.30 2.50 2.34 1 5.0 n 0 - - - - - - E 0 - - - - - - 4.5 n o - - - - - — E o - - - - — - 4.0 n 0 - - - - - - E 0 - - - - - - 3.5 n o - - - - - - E o - - - - - - 3.0 n 2 14.07 14.07 3.12 2.21 2.04 1.07 E 3 10.20 15.54 5.11 2 0 1.04 1.00 2.5 n 1 0.90 10.90 - - 2.74 2.50 E 5 14.32 14.10 0.04 3.04 09 1.91 Note: From The Early Childhood Motor Skills Development Study (1985). §£§ndards for Performance on Selected Fundamental Motor Skills for School of Health Education, Preschool Age Children. Counseling Psychology, and Human Performance, Tabulated data. University, East Lansing, Michigan. Michigan State APPENDIX 8 Parental Information liCHlGAN STATE UN MEOFEDUCATION . SCHOOL 0 M91346 PSYCHOLOGY AND HUM lWKlFCllCLE leer Parent, Recently I spoke 1y dissertation r age boys and girl study as Hell as t The purpose of the stages identified by sieultaneous, h running doom a sho vieu) say he reque froo your child. leesurenents will are and leg joints shorts/sail suits for the Study of H iiichigan State Uni Heesureoent and fi understanding of t also is the potent students and educa only be after you and have given you identified only by results will be tr anonyeous. Upon your arrival he asked to couple studies using huea required before yo you on April 30 or if you change your have any questions 155-9931). Thank you very nuc Sinnerely, in E. Kiger Protect Coordinate Graduate Teaching/ insistent, hotor D Your Soheduled Fil 190 MICHIGAN STATE UNIVERSITY COLLEGE OF EDUCATION 0 SCHOOL OF HEALTH EDUCATION EAST LANSING 0 MICHIGAN 0 48824-1049 COUNSELING PSYCHOLOGY AND HUMAN PERFORMANCE 0 1M SPORTS CIRCLE Dear Parent, Recently I spoke with you concerning an interest in including your child in my dissertation research study on the development of running in preschool age boys and girls. This letter is to inform you of the details of the study as well as the extent of your involvement. The purpose of the study is to do a kinematic analysis of each of the four stages identified in the development of running skill. This will be done by simultaneous, high-speed filming of side and front views of children running down a short runway. Your assistance, (out of camera field of view) may be requested in order to elicit the best possible performance from your child. Prior to the filming, a set of anthropometric measurements will be taken and small stick-on markers will be placed on all arm and leg joints. Children will need to be dressed only in diapers or shorts/swim suits and sneakers. All filming will take place in the Center for the Study of Human Performance (Erickson Hall) on the campus of Michigan State University. Measurement and film data collected will be used to further the understanding of the development of running skill in young children. There also is the potential for using the film to assist in the education of students and educators in running skill development. However this would only be after you have had the opportunity to review the film of your child and have given your written consent. The children in the film will be identified only by subject number and birth date. All calculated data results will be treated with strict confidence and subjects will remain anonymous. Upon your arrival at the Center for the Study of Human Performance you will be asked to complete consent forms according to university regulations for studies using human subjects. Parent signature on the consent forms is required before your child may participate in the study. I will be calling you on April 30 or May 1 to remind you of the filming time you selected. If you change your mind on your child’s participation in this project or have any questions, please call me (office: 353-9459 or 353-3866; home: 355-9931). Thank you very much for your time and effort. Sincerely, Jay E. Kiger PFOiect Coordinator and Graduate Teaching/Research Assistant, Motor Development Your Scheduled Filming Time: M5 U i: an Affirmative Action/Equal Opportu nity Institution ——— iiCHiGAN STATE UNI WWI EDUCATION ' SCI IUUL OF H W88 PSYCHOLOGY AND HUMAN "MS CIRCIE The purpose and tony satisfaction. and an willing to a the risks involved without recrininati i understand the [and/0r my child's] University will pro any other medical program. I understand the with strict confide to view the films a such films may be u Ihild‘s Name: Parent's Signature: Date: 191 MKHHGAN SLATE UNIVERSYFY COLLEGE 01-" EDUCATION 0 SCHOOL 01‘ HEALTH EDUCATION liAS'I' LANSING o MKJyygAN . 4351440...) COUNSELING PSYCHOLOGY AND HUMAN PERFORMANCE ° IM SPORTS CIRCLE Motor Development Dissertation Study Consent Form \ The purpose and extent of involvement in this project has been explained to my satisfaction. I agree to my child's participation in this project and am willing to assist in eliciting responses if necessary. I understand the risks involved and am free to discontinue participation at any time without recrimination. I understand that if I [and/or my child] an injured as a result of my [and/or my child’s] participation in this research project, Michigan State University will provide emergency medical care if necessary, but these and any other medical expenses must be paid from my own health insurance program. I understand the results of my child’s participation will be treated with strict confidence. I also understand that I will have an opportunity to view the films of my child and must give my written permission before such films may be used for ecucational or other purposes. Child's Name: Parent's Signature: Date: AMT/ix 4m Af/irmme'vr x11firm/liquid()fI/mrlunily[nilirulinn iiHlGAN STATE UNI IIIOFHIIJCATTON ' SCHOOL Ol- llIIliiii’SYLIlUlIKiY ANI) IIUMA IMOIIIE Subject Name __ We have chc of Iy/our chi the project of purposes. Parent/Guardian __ N fill of the fi director and/ 2‘ Only sections he used by th educational p hrentliuordinn 192 MICHIGAN STATE UNIV ERSl'I‘Y ’— I{:\T\'T IANSING ' MM lli(}.\1\1 0 SHSli-lfli‘) mun-14:5. 0E EDUCATION . 131314101411-~ 11147413111 14111113411014 COUNSELING PSYCHOLOGY AND HUMAN |11-,11|-()RMAN(15 . 1M SPORTS CIRCLE Running Development Study Film Release Form Subject 0 Subject Name l/we have chosen not to view the Running Development Study film made of my/our child and give my/our permission for the film to be used by the project director and/or Michigan State University for educational purposes. Parent/Guardian Date ___ I/we have viewed the Running Development Study film made of my/our child. All of the film made of my/our child may be used by the project director and/or Michigan State University for educational purposes. Only sections designated below from the film made of my/our child may be used by the project director and/or Michigan State University for educational purposes. Date Parent/Guardian 4 irmurimr .‘Ic'linn 4 I" moi vapnrlum'n' Inelilufirm APPENDIX C Anthropometric Measurement Procedures The followin are described it" those outlined by are recorded to t: Note: To ob1 young subjects it the child assist i will be noted in 1 study measurements body. Several of taken on the left Anthropometric Measurements Procedures The following written descriptions of anthropometric measurements are described for the right side of the body. These procedures follow those outlined by Seefeldt, Haubenstricker, Brown, and Branta (1983) and are recorded to the nearest millimeter. Note: To obtain the most accurate measurement possible on very young subjects it is often necessary to have another person familiar to the child assist in positioning various body segments. Such assistance will be noted in several of the following illustrations. For this study measurements were made on both the right and left side of the body. Several of the pictures will illustrate the measurement being taken on the left side of the body. hnsuenents Usinc Honer Width (Bi Thesubjects stanc uththeir back t1 tahng the measure thnr shoulders 'W Theacronion proc, laud using the in Doe and of the ca: U“thalateral Edl anonion and the 1 until it was in p; 180741 Edge of tl acronion. 194 Measurements Using the Bow Caliper Shoulder Width (Biacromial Diameter). The subjects stand on both feet with their back to the person taking the measurements and let their shoulders “droop down." The acromion processes are pal- pated using the index fingers. One end of the caliper is placed on the lateral edge of one acromion and the other end moved until it was in place on the lateral edge of the other acromion. X1 ”1 1110114 10111 With the SUbjec “18 8885 of the 195 Hip Width (Biiliac Diameter). With the subjects remaining in the same position as for shoulder width, the iliac crests are palpated to locate the points of greatest width. The ends of the caliper are placed on these points for measurement. F0 ”3“" L9” to 100 \g\ Maintaining the lac are asked to flex toward the thin. PUrIlbn Of the lat ““94 0n the tip 197 Forearm Length (Radio-Stylion). Maintaining the body position for the upper-arm measurement, subjects are asked to flex their wrists so that the extended fingers are pointing toward the chin. One end of the caliper is then placed on the posterior Portion of the lateral epicondyle of the humerus and the other end is Placed on the tip of the styloid process of the radius. U EF‘Arm Le” th The SUblects are aking the 091351114 hisplaces the r 90' Site, PRIpa ofthe caliper at Portion of the hu helateral CDndy 196 UEEQL:Brm Length (Acrom-Radiale). The subjects are asked to stand with their right side toward the person taking the measurements and to place their right hand on their stomach. This places the right brachium at their side with the elbow flexed at 90°. After palpating the landmarks, the anthropometrist places one end at the caliper at the top of the lateral projection of the superior Partion of the humerus. The other end is placed in the groove between the lateral condyle of the humerus and the head of the radius. Measurements Using ’__————‘- ' / Main. The subjects right extended and togeth lateral side of the the direction the 5 held parallel to th crease to the tip 0 198 Measurements Using the Shortened Anthropometer Hand Len th. The subjects right hand and fingers are turned palm up, with the fingers . o . h extended and together. The elbow is flexed 90 and held next to t e lateral side of the trunk with the forearm and hand extended forward in t is the direction the subject is facing. The shaft of the anthropome er . 'st held parallel to the fingers, and the hand 15 measured from the wri crease to the tip of the middle finger. V. U 07 Eltl'enit The SUblECts are llith the anthrop the tOn 01 the 1 (just below the the anthrOPomete Note: ASSlstance 4019 I0 achieVe ‘ 199 Upper Extremity Length. The subjects are asked to place their hand in an extended position and to hold it down at their side with a straight arm, palm toward the body. With the anthropometer held in the sagittal plane, one end is placed at the top of the lateral projection of the superior portion of the humerus (just below the lateral projection of the acromion). The other end of the anthropometer is placed at the distal end of the middle finger. Note: Assistance is needed with this measurement if the child is not able to achieve a straight arm on his own as illustrated above. W. The Subjects are apart and their f distributed on 51 Projection of the anthroponEter is 200 M. The subjects are instructed to stand with their feet shoulder width aPart and their right side nearest the anthropometrists, weight evenly distributed on both feet. The right foot is measured from the posterior f the PFOJection of the heel to the tip of the longest toe. The shaft 0 . . t. anthropometer is held parallel to the midline of the foo A . £347.?" Total Le Len th. lith the subjects 1 length, they are a C lateral projection and marked with a s oeasured from this 201 W. With the subjects remaining in the same standing position as for foot length, they are asked to fold their arms across their chest. The most lateral projection of the greater trochanter of the right leg is located The length is and marked with a small dot using a fine tip marking pen. measured from this mark to the inferior boarder of the right malleolus. V ‘1 II ”I Shank Length. The subjects stand Snail bench so that Edge of the lateral the same manner as Sagittal plane, and lateral condyle of lilleolus. 202 Shank Length. The subjects stand on their left foot and place their right foot up on a small bench so that a 90° angle is created at the knee. The proximal Edge of the lateral condyle of the right tibia is located and marked in the same manner as the trochanter. The anthropometer is held in the saOittal plane, and the leg is measured from the superior aspect of the lateral condyle of the tibia to the inferior boarder of the lateral malleolus. Measurements Using Measurements Using the Full Anthropometer Standing Height. The subjects stand on a small bench with heels together and in contact With the wall. The head is positioned in the Frankfort plane with the arms hanging free at their sides. The anthropometer is placed PErpendicular to the floor and parallel to the wall in the mid-frontal Plane. The subjects are asked to stand as tall as they can while the Sliding bar of the anthropometer is brought down on the vertex of the head with slight pressure. The head is stabilized by placing a hand lightly under the subjects jaws. ,- 111110} Tr ochanteric Height- The subjects remain arms over their ches perpendicular to the had been placed on t 204 Trochanteric Hei ht. The subjects remain standing on the bench and are asked to cross their arms over their chest. With the anthropometer in the sagittal plane and PErpendicular to the floor, the sliding bar is lowered to the mark that had been placed on the trochanter for the thigh and leg measurement. S The subjects Sit o anthropomete, is p ”M“ The head is under the Chin. T. the sliding bar 04 the head with 51,9, 205 The subjects sit on the bench with their back against the wall. The anthropometer is placed in the midfrontal plane and perpendicular to the floor. The head is stabilized in the Frankfort plane by light support under the chin. The subjects are asked to sit as tall as they can, and the sliding bar of the anthropometer is brought down on the vertex of the head with slight pressure. APPENDIX D Data Collection Forms Anthropometric Mea Data Sheet height Standing Height Trochanteric Heigh Sitting Height Shoulder Tlidth (Bi Hip hidth (Billiac Upper-Arm Length '( Forearm Length (Fla Total Arm Length Hand Length Total Leg Length Leg (Shank) Lenoth Fenur Length (Tota 206 Name: Anthropometric Measurement Subject # Data Sheet Birthdate: Age-Months: Date: Weight Standing Height Trochanteric Height R: L: Sitting Height Shoulder Width (Biacromial Diameter) Hip Width (Biiliac Diameter) Limbs: __Bigb$____. ___Leit____ Upper-Arm Length (Acromradiale) Forearm Length (Radiostylon) Total Arm Length Hand Length Total Leg Length _____—————— Leq (Shank) Length ___ Femur Length (Total Leg — Shank) __.fl______— jek:3/86 FTLMING 8 Time Started:__ 00541." Frame Rate: Lens: Camera-Subject Dis lanera Calibration 05;}; """"" frame Rate: Lens: \ Camera-Subject Di 5 Camera Calibration ... -.---~-------- lrtificial Lights \ BaFl’gl’ound: \ Reference Marks: ~ ““~-. jek:3/86 FILMING RECORD Time Started: PROJECT: DATE: LOCATION: Time Completed: Camera #1: View: Frame Rate: Shutter: Exposure Time: Lens: f/stop: Camera Height: Camera-Subject Distance: Camera Calibration: Camera #2: View: Frame Rate: Shutter: Exposure Time: Lens: f/stop: Camera Height: Camera-Subject Distance: Camera Calibration: Lighting Conditions: Artificial Lights (Number & Type): Background: Reference Marks: Timing Device: Filming Crew: General Filming Sequence: Misc. Comments: jek:3/86 SUBJECT F“ REI TU Subject ll Start 208 jek:3/86 PROJECT SUBJECT FILMINB SEOUENCE RECORD DATE LOCATION Time Subject # Start End Filming Sequence Comments APPENDIX E Raw Data Tables Table E-l Sub’ect Anthro on SITE AK (amths) EIGHT (kgs) STMTITE EIGHT 209 Table E-l Subject Anthropometric Measurements. ASE (Ionths) 16 23 37 35 45 35 56 43 HEIGHT 1kgs) 9.54 12.34 14.74 16.26 18.2 16.26 22.88 17.78 MWWHB HEIGHT 76.7 84.5 93.2 93.8 101.4 93.8 113.4 100.5 HIDTH 17.3 21.9 21.8 21.5 24.1 21.5 26.1 24.1 MP HIDTH 13.6 16.0 16.5 16.5 17.5 16.5 18.5 16.6 'mun. 3&1 366 4&35 44J5 445 4Lfii {MAE 4L8 H35” “Ml LE5 33.3 34.3 38.4 39.5 4 . UNHH 39.5 49.6 41.25 (A (A FOOT 11.85 13.15 15.35 15.5 16.55 15.5 19.25 15.5 * Stage one male refused to allow measurements other than weight and standing height. Measurements were obtained by hand measuring the various segments in several film views of the subject, us1ng a conversion factor, then averaging the obtained measures for each segment. Table E-2 Subject Running EMOTTE lBBTTT Tu} TENT STTTTTI LETETTT Tum) TUTTT. TH MES TTTSTTTCE Tu) TTTTTL Rt TYRES TTTE TsT EAT STRTTE TTTE Ts) PEST STRTTTE RITTE TTlsT TTTTTTTS SPEED (:15) \ 0 3. 210 Table E-2 Subject Running Descriptors. ENE 3 H F H F H F H F ENHWOE LENBTH (cm) 69.118 87.736 109.907 90.566 158.333 102.264 171.018 169.583 mnesnme LENBTH (co) 36.397 45.755 56.481 45.094 79.630 53.302 85.463 85.938 TMH.R£ CYCLES 103.677 132.076 168.518 139.622 237.037 158.491 250.000 255.208 DISTNCE (ca) TMfl.Rt CYCLES 0.78 0.64 0.74 0.64 0.74 0.63 0.60 0.66 TIfiE (s) TENT STRIE TIME (5) 0.265 0.215 0.255 0.210 0.245 0.210 0.200 0.225 PEAR STRIDE RATE (#751 3.77 4.65 3.92 4.76 4.08 4.76 5.00 4.44 RNOEHTEI (:15) 1.329 2.064 2.277 2.115 3.203 2.516 4.167 3.867 Table E-3 Semental Incline Gender. 84! EMIR 811K H 79.909 T F 75.120 H 81.213 T F 76.418 4 84.915 2 F 78.447 4 79.443 1 F 79.072 \ Table E-3 Segmental Inclinations (degs) for Right and Left Touchdown by Stage and Gender. 211 menrunmmn LETTNHOWN STAE GENDER TRUNK THIGH 51M F1111 TRlN( THISH SHAW FOOT H 79.909 116.414 83.780 171.869 79.779 119.800 91.036 172.725 4 F 75.120 129.435 83.469 177. 627 82.053 115.918 91. 777 183. 918 H 81.213 117.607 94.845 180.000 83.329 106.798 96.115 164.358 3 F 76.418 123.689 102.284 197.904 77.382 117.492 101.673 185.274 H 84.915 124.055 98.326 178.569 87.447 116.762 99.461 188.749 2 F 78.447 127.037 94.999 194.827 81.858 113.962 97.353 189.189 H 79.443 113.386 101.560 169.695 84.892 120.966 95.195 166.185 1 F 79.072 115.578 104.535 172.876 78.154 113.639 98.654 153.437 Table E-4 Se mental lnclina by Stage and Send 0161 11119 600611 0011' 11 75.611 1 9 00.131 1 83.069 1 F 79.716 H 03.25 2 F 00.19: 1 H 79.116 F 75.225 \ W89 “'91" = Wk incl: Table E-4 Segmental Inclinations by Stage and Gender. 212 (degsl for Right and Left Maximum Leg Extension RIGHT 114111141 LE8 EXTENSION LEFT P14118181 LE8 EXTENSION a i QM! HWMR ‘mma 8881 SMMK RBI HEEG TMNK ‘WHH SW8 RBI HESS H 75.611 72.285 48.335 139.634 156.000 79.449 58.068 44.957 100.368 166.889 4 F 80.134 61.876 44.052 92. 725 162.176 77. 890 63.641 50. 316 91 . 005 166. 675 H 83.069 58.393 50.728 122.242 172.335 84.918 62.784 47.095 131.037 164.311 3 F 79.716 72.745 60.423 154.759 167.678 76.769 67.378 66.984 154.551 179.606 H 83.255 73.344 60.485 134.432 167.141 84.297 76.588 62.331 155.074 165.743 2 F 80.194 72.825 64.476 146.822 171.651 81.553 68.120 73.639 158.585 187.519 H 79.416 71.566 72.379 142.925 180.813 79.160 78.691 73.645 161.564 174.954 1 F 75.25 80.717 80.790 165.752 180.073 78.359 84.088 94.458 166.654 190.370 .— * Knee angle = shank inclination + (180° - thigh inclination) Table E-5 Se mental Incline Sender. 900 00001 111.111 1 77.997 1 1 82.675 11 83.069 1 1 77.406 1 06.100 2 F 79.385 1 H 01.092 F 75.896 [\J p—n. (A ale E-5 1mgntal Inclinations (degsl ader. for Right and Left Takeoff by Stage and TUEHTNGGF LBWTAGGF STAGE GENDER TRIM T111811 SIM FOOT TRUTK THIGH SHAW FMT 77. 997 68. 851 35. 976 90.649 79.449 58. 068 44. 957 100. 368 82.675 61.699 37.990 70.973 77.890 63.641 50.316 91.005 83.069 58.393 50.728 122.242 .524 63.887 46. 32 99.091 77.406 70.441 46.365 124.379 81.083 74.575 45.898 128.432 86.100 72.498 46.220 91.569 85.261 77.593 44.997 87.957 79.385 78.775 37.962 118.675 81.530 63.995 47.096 110.672 84.892 67.575 46.470 87.797 80.241 81.764 34.904 58.839 75.896 70.865 59.982 107.652 73.398 83.027 64.137 124.290 Table E-6 Segmental Inclina- Stage and Gender. 81811 11111111181111.1111 11 77.605 11 F 78.490 11 11 84.648 11 F 78.980 10 1 88-401 1a 1 31.798 126 _'.' 79-886 110 214 able E-6 ggmental Inclinations (degs) for tgge and Gender. Right and Left Minimum Knee Angle by RIGHT HINIHUH KNEE ANGLE LEFT HININUH KNEE ANGLE a 1 NEE ENMR “WMC 'WHH QWK FER KEEB WMK 8081 8W8 H81 REES 1'1 77.605 128.091 23.648 86.330 75.557 82. 652 130.5? 25.862 95. 295 75. 305 4 F 78.490 124.089 6.496 87.397 62.407 80.123 113.729 5.663 73.256 71.934 H 84.648 113.593 0.469 60.362 66.876 83.375 119.055 33.289 91.878 94.234 3 F 78.980 102.533 13.144 75.124 90.611 81.426 98.264 12.527 82.996 94.263 H 88.404 133.846 39.045 107.743 85.199 86.651 97.471 12.159 81.472 94.688 2 F 79.325 104.037 15.006 82.280 90.969 86.022 99.699 7.370 74.473 87.671 H 81.798 126.417 48.655 121.675 102.380 73.196 132.797 52.473 127.997 99.676 1 F 79.886 118.442 18.105 93.069 79.663 77.235 118.519 15.492 70.911 76.973 * Knee angle = shank inclination + (180° - thigh inclination) Table E-7 Se mental Inclin Height bx Stage 01011 SITE 00001 111111 11 00.111 1 1 77.750 1 05.611 1 F 76.80 2 1 05.092 F 00.126 1 H 79.013 F 72.192 \ 119 5‘7 ggental Inclinations (degs) for Right and Left Maximum Thigh Segment ght by Stage and Gender. RIGHT NAXIHUH THIGH SEGMENT HEIGHT LEFT MAXIMUM THIGH SEGMENT HEIGHT IPGE GENDER TRIM THIGH 518884 FOOT TRIM THIGH SHARK FIT H 80.114 142.910 74.442 161.377 83.498 149.256 58.461 129.646 4 F 77.750 148.298 92.260 170.000 79.077 148.595 83.716 168.472 H 85.611 139.899 55.796 139.086 84.409 136.685 109.201 196.556 3 F 76.280 138.460 64.901 140.315 77.310 144.687 58.083 145.617 H 85.082 146.310 75.123 159.443 82.280 148.877 77.365 168.693 2 F 80.126 137.148 79.993 166.152 84.196 132.157 62.578 133.150 H 79.043 153.436 85.561 173.019 73.582 144.904 86.533 167.241 1 F 72.492 134.999 56.613 118.372 76.866 136.743 63.438 131.059 Table HS 50 mental Incline forward and Maxim STTGE RlfiiIhllFNT 11180111111!) 71.1 225.0 114.51 48.36 130.78 1e E-8 lgental Inclinations (degs) for Right and Left Arms at Humerus Maximum ward and Maximum Backward Position by Stage and Gender. 571100 01511051 11 r 11 F 11 r 11 9 0100mm 1111131115 100.115 151.092 88.268 90.650 129.060 90.001 106.157 126.446 mam 251.201 191.556 102.555 205.505 157.710 169.018 251.115 207.001 01011110101011 1111211115 71.115 22.115 20.541 15.755 59.550 25.190 - 6.864 15.260 mam: 225.000 100.150 71.055 106.050 48.630 62.269 90.001 50.551 051111111501 HIERUS 114.567 123.687 110.001 119.664 09.519 75.009 120.015 152.011 01011111 185.461 150.251 150.001 165.600 159.772 125.290 209.427 215.202 15111191101010 1111-5118 48.367 55.695 59.006 25.060 20.122 19.069 16.006 17.200 FDREPRH 150.701 71.209 125.111 182.561 11.901 01.117 123.806 75.569 Table E-9 Traun Midline - Se Tell Touchdown b 5 SITE hmm4 mmm 0mm 0mm m ZIDQIUDDF FIG~¢ 9181111181 1001 ‘3 111101 0mm stm~m ZRDQIUDDK 6mm 0mm m KKMJ Ktm~t kde 16111111011 2 E-9 1fMidline - Segment Center-of-Gravity Distance (cm) at Right and LTouchdown by Stage and Gender. STABE 1 2 3 4 00111611 11 F 11 F 11 r 11 r 7007 2.5 5.1 5.9 5.0 0.1 7.1 1.1 0.7 .:_ 0119111 5.5 6.3 5.1 6.0 1.0 0.0 5.9 6.5 :11 7111011 6.9 6.8 0.5 7.1 7.7 0.0 7.0 6.5 2 7007 1.6 6.0 1.5 1.0 9.1 5.0 1.9 1.1 g 5; 511911 6.2 5.5 .: 1.9 7.7 1.2 1.9 5.9 g 0.; 1111011 6.4 5.7 5.1 5.7 6.5 6.5 5.7 6.5 23 119110 5.0 22.6 22.0 10.6 12.5 20.7 2.0 7.2 :90; 5: 7111201111 9.1 16.0 10.5 11.2 15.5 17.5 10.2 15.6 a 2.9 11111511115 7.1 11.6 11.1 11.1 9.0 10.6 11.9 15.6 . 110110 51.0 29.1 20.6 21.5, 20.0 15.0 11.1 15.2 53 711100101 21.6 17.5 11.1 14.6 21.2 12.7 11.5 15.5 52 1611571110 15.0 11.5 10.9 12.1 11.1 12.7 15.5 12.0 91112111211 01.6 11 0.1 R 1.1 R 2.1 R 1.9 R 2.0 111.0 0 9111111171111 7007 7.6 5.6 6.6 9.0 1.1 5.5 5.0 7.1 .5: 0195: 6.5 5.6 5.5 0.9 1.1 5.1 5.0 5.6 3 711151 6.5 5.6 6.2 7.0 5.2 6.1 5.0 5.6 F007 1.1 5.6 1.1 0.0 o o 1 0 96 2 0 § *5 5119111 5.5 6.7 7.0 1.1 5.7 1.1 6.7 6.5 E '53 7111011 65 69 9.6 65 01 70 65 05 L) :3 E 111111 21.5 29.2 29.5 21.1 21.1 52.0 15.1 16.6 - FEREARI‘T 14.6 20.0 22.5 19.2 10.7 25.1 16.3 15.7 E E 1111511115 9.0 15.5 16.4 15.7 16.1 15.2 15.0 12.0 110110 19.5 25.7 22.9 1.9 22.0 20.5 1.0 15.7 as 700001111 16.3 19.1 10.0 11.1 15.0 10.2 12.5 16.6 5*: 1111271115 11.1 11.1 12.5 11.1 0.1 12.5 12.5 11.1 SHOULDER 0 L 2.8 L 2.1 L 3.0 L 4.9 L 6.0 L 1.5 L 3.3 VARIATION Table E-lO Left Takeoff b 011110 Midline - . 66 666 666 666 666 66 666 666 666 666 66 ES :32 E: Em; Em: Ema Ema “—1.563... :53. 6666.63 54 le E~10 0n Midline - Segment Center-of—Gravity Distance (cm) at Right and tmjakeoff by Stage and Gender. 571355 1 2 3 4 EWHR H F H F H F H F 71107 7.6 0.5 6.5 9.9 10.6 9.5 5.6 11.5 011111 6.5 7.1 6.5 .5 9.6 6.5 5.6 9.2 E 1111011 6.5 6.5 6.5 6.0 6.9 6.5 5.6 6.9 11107 1.1 1.2 2.1 5.1 1.9 1.1 5.6 5.7 E 3; 0111111 5.5 1.9 1.1 5.1 2.9 2.1 5.0 1.6 g a 7111111 6.5 5.0 6.5 5.9 1.6 5.9 5.6 0.0 '5: 111111 21.5 27.0 5.5 25.0 27.9 51.0 22.1 20.7 E '5: 711101011 11.6 19.1 19.0 17.0 21.0 21.9 19.2 10.1 ... 11111311110 9.0 11.6 11.0 12.0 19.2 15.0 11.1 16.1 111111 19.6 22.2 16.9 5. 11.5 , 11.5 1.0 16.5 g m 16.5 10.1 16.5 11.6 9.6 11.6 10.6 17.2 22 1111211115 11.1 11.1 11.6 11.6 7.5 11.6 12.5 11.9 0111111571 0 L 2.2 L 2.1 0 L 5.0 11.7 L 1.5 L 2.5 1111111171011 1007 1.2 1.0 5.6 6.0 1.2 5.0 5.5 2.1 011111 6.5 5.2 1.6 .5 1.0 5.0 1.6 2.9 E1 7111011 0.2 5.6 0.0 7.2 5.6 7.1 5.9 1.9 7001 1.1 5. 5.0 7.5 6.2 5.0 1.1 5.2 1% 01110: 6.5 5.0 1.0 7.2 5.9 5.0 5.7 5.6 g 3 7111011 6.5 5.0 1.1 7.1 5.2 6.2 5.9 1.1 111111 25.9 6.1 20.1 6.0 15.0 11.0 0.9 0.9 E; 71111511111 10.1 7.6 10.0 12.1 15.5 15.1 0.9 15.7 .55 111131115 10.6 7.1 11.0 11.1 11.6 11.5 11.1 15.0 119111) 22.6 21.7 20.1 11.5 25.5 17.5 15.7 15.0 5 11111011111 19.0 17.1 12.0 12.1 19.6 15.0 11.0 12.2 22 111071110 15.9 ~ 12.7 9.2 12.1 15.0 15.1 12.9 10.6 SHOULDER L 0.2 R 2.2 L 0.6 R 1.5 R 0.6 R 1.5 R 1.8 0 VRRIRTIUN fable E-ll Drawn Midline -g Left Minimum Knee j RIGHT HINIPIJH KBEE ME LEFT mmnun 10155 W e E-11 1n Midline - Segment Center-of-Gravity Distance (cm) at Right and PMinimum Knee Angle by Stage and Gender. 57100 1 2 5 1 001111011 11 F 11 1= 11 0 11 F 0007 5.1 1.1 5.2 0.1 1.6 6.6 5.6 1.9 E 011111 5.1 2.2 1.0 0.1 5.1 6.1 1.0 1.1 711101 7.0 1.2 5.0 7.5 1.9 6.1 0.6 6.2 g 0007 5.2 11.0 7.7 2.9 0.0 2.9 5.0 -1.6 5 511111 0.7 0.5 7.5 5.2 7.5 1.7 6.2 1.1 g E 701011 9.1 5.6 7.7 1.9 0.9 7.2 0.0 0.2 § :2: , 1111111 27.2 15.7 29.9 10.7 19.5 51.6 7.7 16.5 t '53 011101101 20.6 15.6 22.7 20.5 17.2 25.1 15.0 16.5 E 11101110 15.2 10.0 16.2 15.1 11.6 16.0 12.5 11.6 111110 22.1 20.6 26.9 12.2 51.7 20.9 15.1 22.0 5 01110117111 10.5 10.0 19.2 12.2 21.9 17.2 17.5 19.5 e 111011115 12.6 15.2 10.6 9.9 11.5 11.5 15.1 10.6 SHILDER L 1.7 R 1.4 L 2.9 L 1.6 L 3.2 L 2.1 R1.0 L 2.4 VPRIATILN F801 7.2 11.9 4.4 5.3 3.6 5.6 3.2 8.9 SHRNK 10.5 9.9 7.1 6.8 5.6 7.0 5.7 8.3 E THIGH 10.2 7.0 8.9 8.3 7.6 8.3 8.1 6.9 NET 62 23 09 SJ L7 52 3A 28 E; QWK 62 32 Z? 60 31 56 L9 28 22 “8&1 L2 46 53 62 53 76 '12 56 25.6 26.4 25.7 19.6 18.1 26.8 16.9 14.6 170110111111 19.5 18.3 20.4 16.0 15.4 21.3 18.7 13.9 E 11131115 11.3 12.6 13.3 11.0 10.0 14.4 14.6 11.1 LEFT HINIHLH KNEE ME 12110) 27.5 22.9 21.5 6.8 25.1 16.5 16.2 22.2 20.9 17.1 16.0 12.8 20.1 14.6 17.1 18.1 111911.15 15.4 12.0 11.5 13.6 15.3 12.0 14.8 11.1 R1511 5111111011 R 2.0 0 R 0.7 R 1.8 R 2.1 R 0.9 R 0.8 L 1.4 VARIRTIDN "1 Iable E1 1111 Maximum T111 1 Drawn Midline - SE 3116:" E18128 11111111131 1,6 16 mm mm m 1.6 1W6 mm mm m mmm mwm m m . m mmm m m m 1 m a m :5 .:EE :5 EE sum: 55E Fm: :GE ...IwwmI ...zmzwmm Im.::. t::~x¢: .:GTK s6~$ 552%...“ TGNIK §~k¢t E4 111781111011 Table E-12 Drawn Midline - Segment Center-of—Gravity Distance (cm) at Right and Left Maximum Thigh Segment Height by Stage and Gender. 571181 1 2 3 4 85111181 11 F 11 1 11 1 11 1 1007 5.9 1.1 5.8 6.0 0.7 6.0 5.6 1.6 .:_ 511111 1.1 2.8 1.1 6.5 0.7 6.1 1.6 2.9 g 1:1 7111811 5.1 5.5 6.1 6.5 1.2 7.6 6.5 1.9 f 1007 8.9 9.7 9.6 7.1 9.5 6.9 1.8 5.7 g 5 5111111 8.9 6.2 7.5 5.0 7.1 6.9 1.8 5.6 g 1: 7111811 7.0 1.9 6.5 5.5 6.9 6.9 1.1 1.9 E 1M) 21.7 9.7 21.2 7.5 11.7 17.7 1.5 8.1 g 18110111 19.6 11.1 18.5 12.1 11.7 16.9 10.0 11.1 25 L51 111E888 15.2 9.1 15.5 9.8 10.6 11.7 12.0 15.0 1;: 111118 21.5 .26.9 26.1 20.6 28.2 20.8 17.6 11.7 g 3 1111151101 17.0 18.6 18.5 15.9 21.7 16.9 11.8 11.1 :2 11111511118 11.7 11.8 12.5 11.6 15.8 15.5 15.7 9.8 911111.081 L 0.6 11 0.7 0 11 5.0 11 0.7 11 2.0 71 0.9 L 1.5 9011111711111 1007 8.1 9.5 8.1 11.9 8.5 6.7 8.1 10.1 - 5118 9.8 8.0 1.9 10.1 6.9 6.7 7.5 7.5 u- w 3 711181 9.0 7.1 1.9 7.2 5.8 7.1 7.5 5.7 E . - g 1007 5.7 1.7 1.5 5.6 1.1 5.5 5.1 5.2 +- 5 811111: 6.2 1.7 2.5 1.5 1.1 1.1 1.1 1.8 g 3 7111811 6.1 5.6 5.1 51 1.2 5.5 6.5 5.1 § 11018 5.6 27.1 26.5 22.1 11.2 29.1 19.8 15.2 '— 1: 11510911 15.2 19.1 21.1 11.9 15.5 50.5 19.5 12.7 E :11 111151118 9.2 12.6 15.1 10.1 11.2 15.1 15.5 10.8 C 113 111101 16.0 20.1 16.1 0.0 6.9 11.2 11.6 5.7 ‘J 5 10711181 16.1 11.9 11.5 8.7 8.2 12.1 17.9 12.7 2 111111115 12.5 10.5 9.8 10.9 10.8 8.9 15.5 9.1 8110111181 11 0.8 L 1.0 L 2.1 0 L 2.8 L316 R 0-3 L 2-3 VPRIATION Iable E-IS Linear Disglacem Touchdown to Talc 11111 181181 1111111 1 55.951 1 1 51.721 1 17.511 1 1 15.210 H 11.119 2 F “I482 1 H 17.875 F 11.551 \ Table E-13 Linear Displacement (cm) of Centers of Mass for Leg Segments from Touchdown to Takeoff by Stage and Gender. RIGHT LEFT 511K GENDR 181M THIGH SHAW FEDT TRIM THIEI 81M FOOT 8 53.950 45.866 30.713 18.059 57.835 45.262 29.100 18.105 4 F 51.724 41.558 25.113 16.966 46.216 38.397 27.868 20.414 H 47.561 38.872 26.702 21.824 46.620 38.156 23.871 15.520 3 F 43.240 36.545 24.899 19.252 41.764 35.850 24.752 18.780 H 61.649 50.089 41.036 31.421 50.699 47.681 37.474 28.498 2 F 46.482 44.354 ' 32.183 25.514 39.582 35.662 23.137 19.669 H 37.875 36.597 31.849 29.201 45.739 45.614 39.248 33.198 F 44.331 39.018 26.498 21.024 30.225 28.350 24.709 20.058 Table E-14 W W 11111 1008 1111111. 11 19.801 1 1 11.08 1 19.292 1 1 22.080 1 11.102 2 F 11.212 1 H 15.981 F 21.58 222 Table E-14 Linear Displacement (cm) of Centers of Mass for Leg Segments from Takeoff to Minimum Knee Angle by Stage and Gender. RIGHT LEFT STAGE GENDER TRIM THIGH SHA‘K FDUT TRLN( THIGH SHNK FillT H 39.803 55. 763 66. 025 66.891 61. 642 76.404 89. 245 91.044 4 F 44. 038 55.599 66.166 69.128 40.896 49.327 50.052 50.380 H 39.292 49.286 56.566 58.982 38.502 57.308 55.612 57.686 3 F 22.080 27.357 31.335 28.569 19.387 23.331 27.776 25.778 11 31. 402 40.032 49.641 53.173 14.241 16.809 18.381 18.026 2 F 13.242 17.301 20.947 20.108 20.645 26.118 30.025 28.421 11 15.986 21.682 26.628 27.931 12.688 17.269 23.444 29.164 F 24. $9 33.486 37.943 41.912 32.555 37.198 39.795 39.188 Table E-15 linear Displacem Hininun Knee Ang 81111 18081 TRIM 11 25.602 I F 32.347 H 19.687 1 F 15.828 11 9.450 1 F 21.059 1 H 9.815 F 5. 375 \ Table E-15 Linear Displacement (cm) of Centers of Mass for Leg Segments from Minimum Knee Angle to Maximum Thigh Segment Height by Stage and Gender. RIGHT LEFT STAGE GENDER TRIM THIGH SHAW FIDT TRIM THIGH SHAW FDDT 14 25.602 24.816 39.998 55.362 12.248 13.798 19.273 27.943 4 F 32.347 35.733 46.706 62.855 27.254 32.195 42.776 56.067 14 19.687 26.142 32.130 41.886 28.415 34.197 45.113 61.398 3 F 15.828 20.(89 28.306 36.498 19.472 27.401 34. 774 42.003 1‘1 9. 450 10. 527 16. 752 24. 271 28.116 33.702 46.821 59.510 2 F 21.059 26.811 35.073 46.557 18.490 22.896 30.521 40.266 11 9.865 11.660 17.950 24.103 8.445 8.627 11.045 17.112 F 5.375 6.170 11.173 16.722 11.258 14.235 18.661 25.473 Table E-16 Linear Disglacen Maximum Thigh 88 11111 81081 7111111 11 18.181 1 1 28.521 11 11.111 1 F 22.197 2 N 12285 F 15.985 1 H 15.798 F 20.111 \ Table E-16 Linear Displacement (cm) of Centers of Mass for Leg Segments from Maximum Thigh Segment Height to Touchdown by Stage and Gender. ME” LET STAGE GENDER TRUM THISH 81M FMT TRlM THTBH SPAM FUJT H 38.688 36.262 37.748 44.179 38.052 37.253 35.410 48.474 4 F 28.528 26.773 25.835 24.073 17.234 17.167 18.763 20.711 H 33.641 31.191 36.452 45.331 28.256 26.614 24.283 24.520 3 F 22.697 25.030 30.808 39. T35 16.600 16.966 20.752 26.928 11 32.283 30.274 30.305 36.349 19.078 16.028 18.246 23.355 2 F 13.985 14.625 16.505 19.037 15.362 16.163 17.623 24.054 H 15.798 13.816 15.109 18.051 13.051 15.338 16.731 19.035 F 20.644 20.857 23.907 33.761 14.737 13.301 16.211 25.957 Table E-17 W Gender. STE 8888? H 4 F H 3 F H 2 F H 1 F \ Pd 1’0 U1 Table E-17 Linear Displacement (cm) of Centers of Mass for Arm Segments from Humerus Maximum Forward to Maximum Backward Position by Stage and Gender. MG” U57 MRI HmMR 'WWK HMEMS HHWW mom Hflfifi FWEMH 1'! 59.158 70. 847 56.784 70.502 59.177 48.022 4 F 63.50. 54.699 41.213 97.488 77.297 66.855 M 71.792 65.140 55.990 65.889 61.255 58.194 3 F 49.961 49.087 35.158 38.706 34.417 35.911 H 58.826 54.064 44.550 51.101 50.609 44.103 2 F 51.947 44.628 38.968 . 68.280 61.843 58.104 M 22.021 17.730 16.728 50.945 58.805 56.361 F 53.890 43.007 37.464 51.354 47.922 52.210 Table E-18 Angular Disglace to Takeoff by St mm m n -4 (. 4 F 4 l- H -5' 1—3 3 F -52 H 1 ~51 1-0 2 F -48. H). '1 45. 1 1-0. F ~44. 1‘0; Table E-18 Angular Displacement in Degrees (Radians) to Takeoff by Stage and Gender. 226 of Leg Segments From Touchdown MG” LEW STNiE GENDER THIGH SHANK FmT THIGH 5149M FOOT M -47.563 -47.804 -81.220 -61.732 -46.034 -72.357 (-0.8291 1-0.833l {-1.418) (-1.0751 {-0.8041 {-1.2631 4 F ~67.766 -45.479 -102.681 -52.340 -41.461 -92.913 (-1.1831 10.794) (-1.861) {-0.912) {-0.724) (-1.620) M ~59.214 -44.099 -57.758 -47.185 ~48.525 -81.705 1-1.034) {-0.769) {-1.0091 l-O.823) (-0.848) {-1.426) 3 F -53.253 -55.919 -66.743 -42.917 -55.775 -56.856 (-0.9321 1-0.975) 1-1.282l {-0.747) (-0.971) 1-0.994) H -51.557 -52.106 -87.000 -39.169 -57.554 -100.798 (-0.901) (-0.909) (-1.519) (-0.682) {-0.942) (-1.758) 2 F ~48.262 -57.028 ~76.152 -49.877 -50.257 -78.517 1-0.840) (-0.995) (-1.328) (-0.875) {-0.878} (-1.368) H -45.811 -55.080 -81.898 -39.202 -60.281 -107.346 (-0.7971 (-0.960) (-1.427) (-0.686) {-1.052} (~1.872) 1 F -44.713 -44.553 -65.197 -30.612 - 4.517 —29.147 (-0. 780) 1-0. 778) 1-1. 1381 00.535) (-0.603) 1-0. 508) Table E-19 Angular Disglace4 10 Minimum Knee 4 44444 new 44 4 T 4 4 4 4 ll 5 4 4 F 3 (4 H a. 2 4: F 24 44 '1 54 4 44 F 47 4o \ Table E-19 Angular Displacement in Degrees (Radians) of Leg Segments from Takeoff to Minimum Knee Angle by Stage and Gender. F1188 LEFT STASE GENDER THIGH 3819K F1111 THIGH SHAW. FCDT M 59.239 -12.330 - 4.319 72.480 -19.149 -4.985 11.034) 1-0.214l 1-0.076) 11.267) (-0.323) {-0.090) 4 F 62.420 -31.494 16.424 50.088 -44.653 ~8.131 11.083) 1-0.547) (0.287) (0.874) (-0.078) (-0.142) 11 55. 202 -50. 259 -60. 880 55.168 -13. 293 -7. 213 10. 963) 1-0.881) H.081) 10.964) (-0.231) 1-0. 125) 3 F 32.092 -33.244 49.255 23.689 -33.371 -45.436 (new) enam) been) 1043) 005%) 14LNO H 61.342 -7.175 16.174 19.878 -32.838 -6.485 11.010) (-0.125) 10.283) 10.347) (-0.572) 1-0.113) 2 F 28.262 -22.950 ~36.395 35.704 -39.726 -36. 199 (0.440 (-0.400) 00.635) (0.623) {-0.694) {-0.631) 1'! 58.842 2.185 33.886 51.033 17.569 -69.158 11.027) 10.039) 10.591) 10.890) 10.307) 1-1.206) 1 F 47.577 -41.877 -14.583 35.492 ‘48. 645 53.379 (0.829) 1-0.731) {-0.254) 10.621) 1-0.849) 1—0.934) Table E-20 Angular Disglace4 Knee Angle to Ma) 444444 8708 44 1 4 4 4 2. 44 11 21 4c 4 F 15 4n 1 12. 2 40. F a. 4n. 1' 27. 1 4o. 1 14.: Pd DJ 1:: Table E-ZO Angular Disglacement in Degrees (Radians) of Leg Segments from Minimum Knee Angle to Maximum Thigh Segment Height by Stage and Gender. 818447 LEFT STAGE GENDER 7441844 54444444: FCIJT 4441844 8414444: 7004 44 14.819 50.774 74.597 18.899 32.600 34.354 (0.258) 10.886) 41.309) (0.326) 10.569) 40.8007 4 F 21.209 86.764 82.594 34.866 78.052 95.218 40.4234 41.5097 41.427 (0.609) (1.361) (1.661) H 26.304 55.327 78.724 17.630 75.912 104.678 (0.458) 10.966) 41.374) (0.258) 41.321) (1.832) 3 F 35.927 51.757 65.191 46.423 45.556 82.871 10.626) 40.904) (1.138) 10.709) 40.7947 41.0957 41 12.464 36.708 51.700 51.408 65.206 87.218 40.2174 40.8294 40.905) (0.898) 11.138) 41.5254 2 F 35.111 64.987 83.872 32.458 5.208 58.877 10.578) (1.1557 (1.464) 10.566) 10.963) 11.0254 41 27.019 36.906 51.344 12.107 34.060 39. 244 10.472) 10.644) 40.8987 40.2114 40.592) (0.684) 1 F 16.557 38.508 25.303 18.225 47.946 60.148 (0.224) (0.672) (0.441) (0.319) 10.837) (1.049) Iahle E-21 Angular Disglacm Thigh Segment He: SWIM Table E-21 Angular Displacement in Degrees (Radians) of Leg Segments from Maximum Thigh Segment Height to Touchdown by Stage and Gender. 229 RIGHT LEFT STAGE GENES? THIGH 81M: FCDT THIGH W FOOT )1 -18.416 20.389 9.615 25.905 29.671 42.412 (-0. 321) (0.356) (1.167) (04$) (0.517) (0.740) 4 F -19. 709 -5. 441 4.131 -16.168 11. 481 17.“ (-0.345) (0.097) (0.073) 1-0. 282) (0.201) (0.311) )1 -21. 798 48.276 58.593 -19.868 -5.827 -4.987 1-0. 379) (0. 774) (1.05) (-0.348) 1-0. 102) (-0.086) 3 F -18.997 43.299 62. 990 -11.536 35. 358 40.w6 (-0.332) (0. 755) (1 . 100) (-0.202) (0.618) (0. 713) H -27.737 16.260 10.962 -6.536 8.673 33.581 (-0. 484) (0.284) (0.192) 1-0. 116) (0.151) (0.587) 2 F -15.820 17.244 20.894 -18.891 36.421 53.461 1-0. 276) (0.301) (O. 368) (0330) (0.636) (0. 932) H '37. 238 19.184 -0.144 -30.097 12.310 18. 285 (-0.649) (0.335) (-0.003) 1-0. 525) (0.215) (0.319) 1 F -17.241 46.629 60.801 24.836 40.601 45.254 (‘0.301) (0.813) (1.062) 00.433) (0.709) (0. 790) (able E-22 1414 ular Dis lace WILL 511588081 [NJ DJ 0 Table E-22 Angular Displacement in Degrees (Radians) of Arm Segments from Humerus Maximum Forward to Maximum Backward Position by Stage and Gender. RIGHT LEFT ENE EMER THEME FUENM nnmm FUENM H -113.023 ~141.435 -103.207 -85.952 (~1.972) (2.471) (-1.801) (-1.500) 4 F -125.342 ~142.966 ~105.623 -132.355 ('2.177) (-2.601) (-1.844) (-2.361) N -86.206 -79.237 -72.222 -110.522 (~1.653) (-1.384) (-1.261) (-l.930) 3 F -7.711 -72.937 -56.866 -42.811 (~0.134) (~1.275) (-0.984) (-0.747) H -59.724 -108.296 -49.142 -22.615 (-1.070) {-1.889) (-0.858) (-0.3947 2 F 64.885 476.444 472.305 23.271 40%n7 FLHH) bLfiW 1048 )1 447.030 -26.821 -68.201 -54.677 000”) 008m (4A3) 404m 1 F -112.069 '3.415 -88.945 ~57.005 (-l.893) (-0.060) (-1.550) (-0.994) (able E-23 W W SITE E1081 )1 4144441444 E” 9.11 _\ 4439411441 nulber indica FJ I'JJ ... Table E-23 Distance (cm) Between the Downward Vertical Projection of the Total Body Center of Gravity and the Support Foot at Right and Left Touchdown. STAGE 1 2 Z . 4 GENDER 14 F 41 F 71 F 71 F 41441214417444 7418444 8.529 10.189 14.815 10.755 114.182 11.132 2.983 8.333 L181 9.118 - 5.8804 20.370 10.377 10.983 9.434 5.741 12.083 * Negative number indicates foot landed behind the downward vertical projection of the body center 04 gravity. (able E-24 lam oral (s) (lbs 514 e and Gender E’s—agfi 411411144414 to .1 41444144 Leg Extensim 11747114 Leg Extensim .0 (1414118011 41111011 (0 ,1; (444m Knee A4919 (444444 (441144 04918 ,0; (1)44in41 Thigh 59844 4479411 4311!! Thigh Segmt '05 \ Table E-24 Temporal Stage and Gender. IQ 1.2-I r0 (5) Observations for One Running Cycle of Right and Left Leg by STAGE SEWER LEE HEM Touchdom to Maxim Leg Extension Haximl Leg Extension . to Takeoff Takeoff to l'liniluo Knee Angle Minion: Knee Angle to Maxim Thigh Segoent Height 44844148. 1741944 Segment . Height to Touchdown .19 . .10 . '07 U .06 .04 . .... r44 .07 .06 '09 I 06 .14 .08 .07 .00 . .14 . . 07 .11 .10 .07 .09 .09 .09 .03 I07 .07 .11 .03 . .11 .15 .15 .14 .15 .01 .01 .13 . .15 APPENDIX F Statistical Analyses Tables 11118 N 1111545 for Star Wean- 111101 111.180 117.301 9101 103.050 96.921 1011 171.290 159.81( \ 4418144441444 in 41944 sh Table F-2 £1111 sis for Send 4 W- \ 111181 1011 233 Table F-l Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Touchdown. HMEHBNS 1 2 3 4 4 14 L 44 L 44 L R L 18.24 THIGH 114.480 117.300 125.550 115.360 120.650 112.140 122.920 117.860 0.69 .6914 51M 103.050 96.924 96.660 98.410 98.560 98.899 83.620 91.406 30.66 .0391! F007 171.290 159.810 186.700 188.970 188.950 174.820 174.750 178.320 1.37 .4799 * Significance in right shank inclination: 1 3 4 —_. —— Table F-2 Analysis for Gender Effect on Segmental Inclinations (deg) at Right and Left Touchdown. 88441484 (EMS 444415 FEl‘hAli 4 p 44 L R L 12,24 THIGH 117.870 115.250 123.930 118.080 2.08 .3245 5448444 94.828 95.452 98.322 97.384 2.49 .2884 FEET 175.030 173.000 185.810 177.950 3.43 .2259 110144 F -3 114414515 for Sta Left Takeoff. 111181 69.20 82.31 81111 $1.226 49.52 1071 77.720 91.56 \ 14018 F -4 114441 515 far Bend 181 w. \ THIGH F011 10 (A .b Table F-3 Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Takeoff. SHHEMNG 1 2 3 4 F 14 R L R L 14 L 44 L 48,27 THIGH 69.220 82.395 75.636 70.794 64.417 69.231 65.275 60.854 0.76 .6659 5888K 53.226 49.520 42.091 46.046 48.546 46.215 36.983 47.636 2.60 .3040 F887 97.720 91.560 105.120 99.310 123.310 113.760 80.810 95.690 0.68 .6983 Table F-4 analysis for Sender Effect on Segmental Inclinations (deg) at Right and Left Takeoff. 88447844484448 44448 4424444415 4 p 14 L 44 L 42,24 4441844 88.829 70.328 70.445 71.309 0.28 .7788 5449144 44.848 42.847 45.575 51.882 3.58 .2192 44174 98.060 88.580 105.420 113.600 1.24 .4488 441419 F6 Lift—“MM 4104 74.144 81-3 9m 76.534 SW 4414 151.3“ “’4'“ 444414 4414 440.443 182-64 44541 Table F‘6 44.4 515 for Gel L W9 \ THIGH 91444 F4111 404411 ”E My LN lnee angle = shan 54041414141118 for left 5 Table F-5 235 Analysis for Stage Effect on Segmental Inclinations (deg) at Right and Left Maximum Leg Extension. SHHEEWG 3 F p R L R L R R L (6;) THIfil 76.141 81.389 73.084 72.354 65.569 65.081 67.080 60.854 1.20 .5211 SM 76.584 84.051 62.480 67.985 55.575 57.039 46.193 47.636 3.21 .2563 Elm 154.341 164.109 140.630 156.829 138.500 142.794 116.186 95.686 9.39 .0994 HHWl KNEE 180.443 182.662 169.396 176.631 170.006 171.958 159.090 166.782 3.61 .2329 “EUR 5 * Actual knee angle = shank inclination + (180° - thigh inclination). Table F-6 igalysis for Gender Effect on Segmental Inclinations (deg) Jfit Maximum Leg Extension. at Right and BHWEififlfi ROLE FM F p R L R L (LE THIBl 68.897 69.033 72.041 70.807 0.17 .8546 W 57.982 57.007 62.435 71.349 31.70 .0306“ FOOT 134.810 137.011 140.016 142.699 0.47 .6797 “3&1 KNEE 169.072 167.974 170.394 181.042 3.65 .2148 "EUR {Etna knee angle = shank inclination 4 (180° - thigh inclination). 1* Significance for left shank only Table F-7 Analysis for St Touchdown and T 1111111011 79.257 81 11110): 81.394 71 M 14019 H; An“ 515 10r Gen W \ "100044 WEIR 236 Table F-7 Analysis for Stage Effect on Trunk Inclination (deg) at Right and Left Touchdown and Takeoff. SHHEENE 1 2 3 4 F p R L R L R L R L 16,2) TUUEHBOHN 79.257 81.523 81.681 84.652 78.815 80.355 77.514 80.916 0.59 .7403 ' TRKEUFF 80.394 76.812 82.742 83.395 80.247 83.303 80.346 78.669 6.73 .1349 .— able F-8 galysis for Gender Effect on Trunk Inclination (deg) at Right and Left Qgchdown and Takeoff. EMEREWE HlE FEW£ F p R L R L Q3) TWWN 81.370 83.862 77.264 79.862 6.13 .1402 TAKEDFF 83.014 82.619 78.840 78.475 11.38 .0808 Table F-9 Analysis for St Left Minimum Kn 111181 122.129 125.1 0191 31.380 33.9 F1111 107.370 99.4 117111 1118 91.020 88.31 11814 \ 111114141 knee angle : 51181 Table F~10 Wm \ M 115.1 11198 angle : Shank able F-9 lglysis for Stage Effect on Segmental Inclinations (deg) at Right and eft Minimum Knee Angle. 318815 ENE 12 L n L n l. n L (6,2) '7 1111811 122. 429 125.658 118.941 98.585 108.063 108.659 126.090 122.143 9.51 .0982 SM 33.380 33.982 27.030 9.764 6.810 22.908 15.070 15.762 0.67 .7037 F081 107.370 99.450 95.010 77.970 67.740 87.440 86.860 84.280 0.60 .7361 HHWl IGEE 91.020 88.324 88.080 91.179 78.740 94.248 68.980 73.619 0.93 .6000 MB Eel knee angle = shank inclination + (130° - thigh inclination). ble F-lO glxsis for Bender Effect on Segmental Inclinations (deg) at Right and Ltghinimum Knee Angle. HMERH$EE 110115 FEMLE F p R L R L (2,21 THIGH 125.487 119.970 112.275 107.553 36.60 .0266 SHRNK 27.954 30.946 13.188 10.263 3.71 .2122 F1101 94. 030 99. 160 84.470 75.410 1. 40 .4158 HHWI KNEE 82.500 90.976 80.910 82.710 1.81 .3563 ”EU? .;¥ :tual knee angle = 5hank inclination + (180° - thigh inclination). lallle F-ll 1na1515 for Stat left Maximum Thit _____._._——- 111101 144.217 140.821 5111 71.090 74.991 1011 145.700 149.150 \ lable F-12 lnal 515 for Send \ 11111311 F1111 238 le F-ll Lysis for Stage Effect on Segmental Inclinations (deg) at Right and t Maximum Thigh Segment Height. SUHEHWfi I 2 3 4 F p R L R L R L n L (6,2) SH 144.217 140.823 141.729 140.517 139.179 140.686 145.604 148.925 0.14 .9734 NK 71.090 74.990 77.560 69.970 60.350 83.640 83.350 71.090 0.24 .9246 1 145.700 149.150 162.800 150.920 139.700 171.110 164.690 149.060 0.22 .9351 e F-12 xsis for Gender Effect on Segmental Inclinations (deg) at Right and _flaximum Thigh Segment Height. EMHQENS 1441.15 FEMLE F p R L R L (AD 11111314 145.639 144.930 139.730 140.540 0.46 .6fi6 SHRNK 72.730 82.890 73.440 66.950 0.40 .7151 FIT 158.230 165.530 148.710 144.590 0.39 .7204 ntle F-13 lnal 515 for Sta W 10148 111ml; 121.100 119 mm 221.680 167 11001111 111E115 46.610 51 11118411 206.560 102 111816 1180’ 78.470 68. 11111111 ISlqnlflcance in right 11 ble F-13 alysis for Stage Effect on Segmental Inclinations (deg) at Right and ftfiHumerus Maximum Forward and Backward. EWEJEMB HUMERUS 121.100 119.120 93.450 118.832 109.530 81.179 116.300 126.014 37.74 .0206 FUREARH 221.680 167.860 192.830 156.800 153.370 141.530 219.620 211.310 1.12 .5422 HUHERUS 46.630 51.030 36.150 41.030 32.420 23.750 4.200 17.050 1.31 .4927 Fm 206.560 102.540 90.460 152.840 55.450 63.050 74.180 99.690 561.51 .0018? line 961501: 78.470 68.100 57.800 77.800 77.110 57.430 112.100 108.970 1.12 .5414 ”EN Significance in right forearm inclination: 1 3 4 .— fl Table F-14 lnal sis for Ge MW 8118490 240 11319 F-14 talysis for Gender Effect on Segmental Inclinations (deg) at Right and fitHumerus Maximum Forward and Backward. 101101 HMERHEMS 1W}: FEM}: F p R L R L (2,2) HEM“) HUHERUS 107.900 110.483 112.290 112.093 0.04 .9626 FIREPRH 200.830 176.170 192.920 162.590 0.37 .7302 Hflflflm 111911.15 33.040 38.150 26.660 28. 280 0.79 .5599 Fm 109.420 105.670 103.900 103. 380 4. 29 . 1W9 lfllflfi RANEE 8F 74.860 72.330 87.890 83.820 0.64 .6112 1a111eF-15 lnalysis for Stat Vertical Project: ant at Right ant 18811 111811 LEFT \ 11151100.” percent 04 star 11611 H), 3111th 1‘" 59nd Fertlcal Pro‘ecti not at R1 ht and \ 10.11111 1118 N 51m : patent 81 stam 1e F-15 lysis for Stage Effect on the Distance (cm) Between the Downward Lical Projection of the Total Body Center of Gravity and the Support 5 at Right and Left Touchdown. 241 QMEHENB F p l 3 4 16,2) E18111 80.6 93.5 97.6 107 Tflflfiflfl 0J8) $8? 81897 9. 559 12.785 10.657 5.648 11211 114) 111) (5) LEFT 1.729 15.373 11.198 8.912 12) 116) 112) (8) E = percent of standing height. e F-16 ygjs for Bender Effect on the Distance (cm) Between the Downward ical Projection of the Total Body Center of Gravity and the Support cgt Right and Left Touchdown. semen 1150115 F n 1181: mm (2.2) ,_ tclan 96.2 93.2 m 1.41 .4156 men 9.122 10.102 1911 1111 LEFT 12.048 6.558 1127 171 E: percent of standing height. 111118 F-l7 Analysis for St tint Segments C 61166 1001811816 it man 1110115116 11181 6.06 m 0111 5.74 17) 817 5.11 (6) 1118113 14.08 117. 111W 19.47. 1241 1111) 10.211 1371 1088815116 11181 6.1141 (81 5191' 5.010 m ”“1 1.712 (S) ”“115 9.454 1121 W 12.70: (161 1110 14.180 1101 61:18 111101 2.1.17 (31 1115th. : PHCent of S 242 'able F-17 inalysis for Stage Effect on the Distance (cm) Between Drawn Midline and :imh Segments Centers of Gravity for Right and Left Touchdown. n__, 18.81811415ch R L 9 L n L n L (6,2) % 115180 80.6 93.5 97.6 107 StFPDRT 5101: 1111611 6.085 5.950 5.557 6.975 6.540 5.777 6.129 5.658 0.528 .7695 1774 177 (6) (7) (6) (6) (6) 151 5144144 5.742 6.039 5.150 7.257 5.957 4.593 4.415 6.658 0.921 .6042 177 (7) (51 (8) (6) 151 141 (6) 5007 5.514 6.581 5.061 8.156 6.189 4.696 4.632 6.582 0.228 .9004 16) (81 131 (8) 161 45) 141 (6) means 14.058 12.530 11.646 15.023 15.545 15.628 12.636 13.509 0.441 .8151 1171 (16) 1121 (16) (141 (16) 1121 115) 50450101 19.475 17.699 14.343 20.860 16.911 22.050 14.011 15.014 5.167 .2594 1241 (221 115) 1221 1177 1221 1131 1141 14901 50.218 25.344 20.973 26.842 21.918 26.547 14.676 16.012 3.559 .2485 137) 1511 1221 1297 1227 1277 1147 1151 10181139181 SIDE 01181 6.841 6.733 7.679 8.066 7.857 7.957 7.155 7.429 0.275 .9075 (81 (8) (8) (9) (8) (8) 171 (7) 81485: 5.810 6.601 5.734 5.925 6.031 4.894 6.231 6.601 0.066 .9954 171 (8) (61 (6) (6) 45) (6) (6) 7007 5.712 5.521 4.441 2.455 3.887 0.512 6.396 6.194 0.291 .8987 151 (4) 157 (3) 141 1.51 (6) (6) 1495885 9.454 11.099 12.744 11.836 10.182 10.210 13.767 11.099 0.545 .6383 (12) 1141 1141 1131 1107 1101 113) 1101 FDREARH 12.703 17.874 16.377 14.542 15.387 17.002 12.947 14.475 4.885 .1796 116) 1221 1177 (16) 116) 117) 1121 1141 14907 14.180 22.650 16.757 13.911 16.595 21.522 4.611 10.261 0.593 .8416 (18) (28) (18) 1157 4171 (221 14) 191 514111.088 vummm 2.337 1.399 1.608 1.137 2.334 2.746 0.512 2.435 0.324 mos 451 121 421 (11 127 157 1.41 127 I Distance = percent of standing height. Iable F-18 Anal 51's for Be and Limb 513 men 68M MUM SIDE fEIEiT WT SIDE iHIEi 1001 “811011 81015 111181 FUJI WWI) 9mm 11111141101 M : Pficmt of Sta 243 1e F-lB li§i5 for Bender Effect on the Distance (cm) Between Drawn Midline _L1mb Segments Centers of Gravity for Right and Left Touchdown. 8121011511 11411: 7511415 F p g (EIGHT 96.2 93,2 QPHRTSHE 18188 5.989 5.855 6.065 6.314 0.219 .8201 (61* (6) (6) (7) SHflNK 5.791 5.472 3.841 6.291 4.104 .1959 (6) (6) (4) (6) F081 5.821 5.999 3.777 7.008 0.523 .6567 (6) (6) (4) (7) HUfiERUS 13.101 14.317 12.842 14.028 0.039 .9629 (14) (15) (14) (15) FUREQRH 17.861 18.036 14.508 19.776 2.519 .2841 (18) (19) (16) (21) HAND 23.668 21.834 20.224 25.538 0.397 .7159 (25) (23) (22) (27) MNHPHRTSHE THIGH 7.659 7.705 7.106 7.388 0.669 .5993 (8) (8) (8) (8) SHANK 5.176 5.867 6.727 5.325 1.205 .4534 (5) (6) (7) (6) F801 2.673 3.700 6.545 2.541 3.258 .2349 (3) (4) (7) (3) HUHERUS 10.794 10.954 12.279 11.469 0.362 .7342 (11) (11) (13) (12) FUREARH 12.902 15.603 15.785 16.343 6.229 .1383 (13) (16) (17) (18) HAND 10.781 17.520 15.281 16.642 0.693 .5906 (11) (18) (16) (18) Sfluflm VARIATION 2.158 2.116 1.237 1.761 0-924 -5199 (2) (2) (1) (2) tance = percent of standing height. Fable F-l‘) Wis—11.51 Limb Segments C 01161 1111171111 11 111811 3110115111 11181 6.1; 181 11111 4.01 151 11101 2.62 131 "15116 1109 114 W 17.18 121 “"0 20.841 1261 108410115111 181 W 6.941 (8) H1111 7.971 1101 ””13 12.183 1151 mm 17.005 1211 H111 21.650 13 5mm 1) 111111101 1111 111 401513!“ : Meat 01 st .e F-19 244 Lysis for Stage Effect on the Distance (cm) Between Drawn Midline and 1 Segments Centers of Gravity for Right and Left Takeoff. F4181: _ 2 3 4 F p .1er SIDE 11 L 11 L R L 11 L 16.21 £18117 80.6 93.5 97.6 107 11117 SIDE 711181 6.177 6.902 6.142 7.613 5.263 5.568 6.812 5.397 0.279 .9055 1814 181 161 181 151 161 161 151 81411 4.061 4.749 5.917 6.066 2.498 3.591 5.142 5.774 1.749 .4075 151 161 141 161 121 131 151 141 1007 2.627 2.618 2.586 5.189 1.489 2.502 4.701 3.993 2.185 .3471 131 151 151 161 121 131 141 141 11751118 11.099 8.822 11.587 12.568 9.460 11.562 13.725 12.050 1.475 .4567 1141 1111 1121 1131 1101 1121 1151 1111 1111817111 17.180 12.981 14.015 15.417 12.091 14.554 15.911 11.266 0.357 .8617 1211 1161 1151 1161 1121 1151 1131 1101 1191111 20.849 14.966 11.165 13.201 14.005 13.556 7.577 4.954 0.397 .8394 1261 1181 1121 1141 1141 1141 171 151 1111410117 SIDE 7111811 6.277 5.699 6.567 5.740 6.628 5.684 6.237 4.991 0.085 .9921 181 171 171 161 171 161 161 151 5140414 6.941 5.699 7.417 5.615 7.974 5.853 7.587 3.637 0.217 .9387 181 171 181 161 181 161 171 151 1007 7.971 5.002 8.098 5.267 10.039 5.998 8.557 4.655 0.093 .9896 1101 161 191 161 1101 161 181 141 14112808 12.183 15.396 13.765 10.624 17.552 15.417 15.259 11.755 0.738 .6751 1151 1171 1151 1111 1181 1141 1141 1111 11116111111 17.005 18.045 18.849 12.173 24.475 17.275 18.813 13.493 2.454 .3175 1211 1221 1201 1131 1251 1181 1181 1131 4 111410 24.650 23.637 25.695 17.347 51.560 21.598 21.405 14.561 1.185 .5251 1311 1291 1271 1181 1321 1221 1201 1131 1181 ITION 1.111 1.132 1,055 1.053 3.729 1.059 1.919 1.181 0.133 .9769 111 111 111 111 14) (I) 1-2’ W 1tance = percent of standing height. Table F-ZO A081 51's for G and Limb 88 me E1081 IMF SIDE LEIGH WT SIDE 111181 8196' FLDI WWI SIDE 111181 F1111 1W108 “Wm 1M) SmU181 11111111011 m : patent of St 245 ,e F-20 Lysis for Gender Effect on the Distance (cm) Between Drawn Midline LLgmb Segments Centers of Gravity for Right and Left Takeoff. GENDER HPLE FEME F 9 1518117 96.2 95.2 SPHRTSHE 78188 5.762 6.440 6.436- 6.200 0.397 .7159 (6)! (7) (7) (7) SHANK 3.606 4.141 4.203 4.849 1.699 .3705 (4) (4) (4) (5) F007 2.194 3.631 3.508 3.520 2.589 .2787 (2) (4) (4) (4) HUHERUS 10.627 11.804 12.307 10.698 4.352 .1869 (11) (12) (13) (11) FDREARH 13.241 14.835 15.557 12.174 1.366 .4226 (14) (15) (161 (13) HAND 13.200 14.547 13.619 8.772 0.522 .6571 (14) (15) (15) (9) 1H6U9GUSHE THIGH 6.284 5.464 6.571 5.596 0.218 .8210 (6) (6) (7) (6) SHHNK 7.012 4.991 7.848 5.411 0.134 .8820 (N 5) (m (M FUJI 7.524 4.431 9.798 6.020 0.994 .5015 (8) (5) (10) (6) 888E889 14.554 12.455 14.816 12.091 0.035 .9665 (15) (13) (16) (131 FUREARH 19.420 16.331 20.151 14.161 1.528 .3955 (20) (17) (22) (15) “8ND 24.267 21.041 27.288 17.330 1.697 .3708 (25) (22) (29) (191 901MB VARIATION 2.355 0.810 1.553 1.299 0.207 .8283 (2) (.8) (2) (2) tmm=pemMoffimfimhd¢t (able F-21 Anal 51's for S) Limb Segments 1 114111 11111543111114 111111 111111115111 11111 5.5 11; 1144 1.111 151 F007 1.14 141 141915 15.02 1151 FEW 17.152 1211 “‘0 21.414 1251 4111141111111 11111 7.452 111 W 1.514 1111 1111 14.511 1101 1114115 12.102 1111 m 18.614 1251 4111 25.501 1121 91111111 1111111111 1.514 121 = me") 91 51de 246 e F-21 Lsis for Stage Effect on the Distance (cm) Between Drawn Midline and _§egments Centers of Gravity for Right and Left Minimum Knee Angle. 81881 1 2 3 4 1 p 1155 MGLE SIDE P. L 14 L 11 L 11 L 15,21 ELM 80.5 93.5 97.5 107 81 5105 1111814 5.52 5.813 5.524 5.752 5.514 5.429 7.415 5.355 0.838 .5340 1714 171 171 151 151 151 171 151 8144144 3.828 4.573 5.459 4.345 4.720 4.301 4.435 3.828 1.759 .4042 151 151 171 151 151 141 141 141 1887 3.142 4.501 5.551 3.308 4.091 3.422 4.255 3.095 0.710 .5851 141 151 171 141 141 141 141 131 11111105 13.025 13.582 15.800 12.551 15.305 13.548 13.557 12.954 0.154 .9541 1151 1171 1171 1131 1151 1141 1131 1121 181451104 17.132 19.022 21.509 14.392 21.318 17.372 15.053 17.554 0.455 .8019 1211 1241 1231 1151 1221 1181 1141 1151 1114111 21.434 25.153 22.811 14.128 25.529 20.797 11.975 19.211 0.413 .8305 1251 1311 1241 1151 1251 1211 1111 (18) 142881 SIDE 18181 7.452 8.507 5.285 8.582 8.055 7.979 4.548 7.537 0.225 .9338 191 1111 171 191 181 181 141 171 3.149144 8.514 10.195 5.280 5.941 5.014 5.291 5.272 7.012 1.525 .4474 1111 1131 151 171 151 151 151 151 41111 8.511 9.528 5.310 4.855 1.434 4.579 1.110 5.070 0.855 .5275 1101 1121 151 151 111 151 111 151 111-£8115 12.902 11.919 10.248 12.157 12.859 12.210 12.977 12.873 0.212 .9415 1151 1151 1111 1131 1131 1121 1121 1121 111514911 18.514 18.873 15.715 18.193 19.579 18.339 18.505 15.294 0.148 .9709 1231 1231 1171 1191 1201 1191 1171 1151 441 25.501 25.003 19.559 22.554 25.309 22.432 18.558 15.747 0.404 .8353 1321 1321 1211 1241 1271 1231 1171 1151 =14 1011 151,11 1,024 2.255 1.259 2.550 1.504 1.700 1.101 0.107 .9855 121 111 121 111 131 121 121 111 me = percent of standing height. (1018 PM 4111] 515 for GEI and Limb Se men? 1.01111- (8081 MN DEE ME 31 5180 9.11011 SIDE (H181 511011 F031 HIERUS PM 100 100.8108 SIDE T1081 511441 F001 1110013 1041 51411181 41111111111 014...\ = Percent of stand 247 1-22 Leis for Gender Effect on the Distance (cm) Between Drawn Midline L1_mb Segments Centers of Gravity for Right and Left Minimum Knee :— 33“? 84E FBWI p mNKMI4wa£suE R 1 R L (23, EIGHT 95.2 93.2 SPHRTSmE 8881 55% 5551 508 5501 0021 AME 104 01 01 01 580 055 4JES 1052 035 05m .052 5) 18 10 6) 100 39D :005 025 4151 0AQI.£M6 n1 (5 01 10 1uens 1020 M583 1023 HLU4 005 .550 um 151 15) um 10558 1000 185M 1008 1555 045 .001 0% 1H) 12» (N) 14418 20.325 22.555 20.550 17.079 0.548 .5057 121 my 02 um 1ueunn1sw1 0mm 020 8J2 045 259 225 .209 81 1% 15 m1 EHMK 230 7JW3 ELNZ 802 305 .ZWB 0) 1n (0 W) HBT 4J3? 05H 320 28W 205 .257 n1 (5 18 m1 iflfififi 13201 1230 1028 122W 090 .559 (M) an 02 05 18080 102n 0055 1005 1235 05m .5m5 120 (H) 101 um 188 2085 2:55 2023 ZLBU 0001 302 120 02 um 05 50108 kumun 2501 2004 005 00m 085 .8w5 12 18 Q) (U ce = percent of standing height. Table F-23 Analysis for St Limb Segments C Segment Height. 11111 111111515115 11 11151 1115115115 11151 5.5 171 111111 3.51 111 11111 2.65 131 "MB 12.33 1151 W 15.331 1191 W) 15.711 1191 1{11911111119115 THIEH 5.909 171 W 7.51 191 11111 9.319 1111 ”'9“ 11.772 1151 “W 17.734 1221 W” 21.12 1301 1111111111 0.753 1.91 W = Pertent of! 1 F-23 [sis for Stage Effect on the Distance (cm) Between Drawn Midline and L§egments Centers of Gravity for Right and Left Maximum Thigh {fit Height. 18? 3 1 p 118151115 11 L 11 L 11 L 11 1 15.21 @111 80.5 93.5 97.5 107 1151115 11181 5.355 5.975 5.339 5.217 5.873 1.715 5.582 5.781 10135 .0925 1711 171 171 151 151 151 151 151 11101.1( 3.553 5.115 5.377 3.310 3.539 2.913 3.771 1.500 1.557 .1230 111 171 151 111 111 131 131 111 1181 2.551 5.211 1.938 2.512 3.311 3.217 3.585 3.127 2.1: .2821 131 151 151 131 131 131 131 131 111511115 12.31 11.391 11.530 10.309 11.111 9.853 12.513 12.199 0.213 .9110 1151 1111 1121 1111 1111 1101 1121 1111 81112111111 15.338 15.523 15.155 11.580 11.305 10.131 10.583 15.272 0.517 .7753 1191 1191 1151 1121 1151 1101 1101 1111 1111 15.731 18.015 11.315 8.019 11.702 10.570 1.712 10.155 0211 .9211 1191 1231 1151 191 1151 1111 111 1101 1111:1111 9105 11181 5.909 8.221 1.927 5.059 5.951 5.155 1.173 5.507 0.511 .7533 171 1101 151 151 171 171 111 171 1111111 7.581 8.915 5.151 7.508 1.158 5.811 2.713 7.329 0.813 .5320 191 1111 151 181 171 171 121 171 1111 9.318 8.828 8.501 10.002 8.109 7.538 3.770 9.128 0.550 .7113 1111 1111 191 1111 (8) 181 111 181 1138115 11.772 10.895 11.957 12.919 13.531 11.55 11.719 13.022 0.228 .9332 1151 1111 1131 1111 1111 1151 1111 1121 REAR?! 17.781 17.291 15.059 18.027 19.301 22.900 1305 15.0% 0.578 .7150 1221 1211 1171 1191 1201 1231 1121 1151 1110 21.121 25.193 23.199 21.391 21.515 21.535 11.535 17.511 0521 .7718 1301 1321 1251 1251 1251 1221 114) (16) 11 011 0753 0920 1.507 1.219 1.355 3.153 1.113 1.301 1.118 .5130 1.91 111 121 111 (I) (3) 111 “’ tance = percent of standing height. fable F-24 111111515 for Se and Limb Se men Segment Height. ENIER FAX THIGf SIB EIGHT EMT SIDE THIGH 9M "1151111111 5111 HIGH F03? WI) 90111181 1151111101 249 a F-24 [sis for Gender Effect on the Distance (cm) Between Drawn Midline Limb Segments Centers of Gravity for Right and Left Maximum Thigh ent Height. GENDER 11115 11211115 F p HEIGHT 96.2 QPHRTSHE THIGH 5.567 5.597 6.000 5.264 12.249 .0755 (6) (6) (6) (6) SHANK 3.529 3.550 4.598 4.569 0.503 .6654 (4) (4) (5) (5) F007 3.507 2.850 3.750 4.199 3.275 .2339 (4) (3) (4) (4) HUHERUS 12.817 12.092 10.992 9.783 2.458 .2892 ()3) (13) (12) ((0) FUREAHH 14.087 14.235 12.850 12.068 0.325 .7549 (15) ((5) (14) ((3) HAND 13.979 13.413 10.766 10.002 0.186 .8434 (14) (14) (12) (ll) KNWWUHSHK THIGH 6.128 6.760 5.004 6.066 0.575 .6348 (6) (7) (5) (7) SHANK 6.364 7.243 4.948 0.056 0.339 .7201 (7) (7) (5) (9) FOOT 7.411 8.248 7.437 8.248 0.430 .6992 (0) (9) (8) (9) HUHERUS 12.871 13.448 11.618 12.283 0.726 .5795 ((3) (14) (12) (13) FUREARH 17.935 17.772 15.185 19.381 1.161 .4627 (19) (18) (16) (21) HAND 23.363 20.976 20.039 23.542 0.500 .6667 (24) (22) (22) (25) QULMR VARIATION 0.575 1.509 1.749 1.714 3.989 .2004 0m :mm=p«mMofdmfimhd¢L (fl (fl (3 Table F-25 Analysis for 5 Right and Left Table F‘26 1”“ 515 for St \ 519mm 250 (ble F-25 [Elysis for Stage Effect on Time (s) in Support and Nonsupport for lght and Left Leg Running Cycles. 570E F p 1 2 3 4 10,2) 3mm 25.000 .0390 RIGHT 0.230 0.210 0.170 0.150 LEFT 0.225 0.200 0.175 0.140 W027 0.070 .9930 RIGHT 0.250 0.255 0.275 0.290 LEFT 0.240 0.245 0.270 0.200 ble F-26 alysis for Stage Effect on Total Time (s) in Support and Nonsupport. STAE F p 1 2 3 4 13,31 SUPPORT 0.675 0.615 0.530 0.445 0.297 .8956 MT 0.000 0.005 0.155 0.100 Table F-27 Analysis for Be Right and Left Table F-23 MW \ ale F-27 alysis for Gender Effect on Time (s) in Support and Nonsupport for [ht and Left Leg RunninggCycles. GENDER F p mus 7151-0115 12,2) WT 20.000 .0570 men 0.195 0.105 LET-T 0.202 0.107 mama 0.055 .5592 mm 0.285 0.245 LEFT 0.207 0.250 'le F-28 :lysis for Gender Effect on Total Time (s) in Support and Nonsupport. 015m F p HALE m (1,3) 51mm 0.007 0.525 0.700 .5590 11115117130127 0.120 0.122 Table F-29 Analysis for St for Right and L Table F-so “"31 sis { W 'able F-29 palysis for Stage Effect on Percent of Cycle in g£_Right and Left Leg. 252 Support and Nonsupport 57005 F p 1 2 3 4 10,21 51mm 0.511 .7784 RIGHT 47.500 45.500 30.000 35. 500 LEFT 47.500 45.m0 40.000 33.000 ma 0.511 .7704 9130 52.500 54.500 02.000 04.500 LEFT 52.500 55.000 00.000 07.000 ale F-3O aLysis for Stage Effect on Total Percent of Cycles in Support and nsupport. SHE F p l 2 3 _4 (Ln SPHRT 9050 815W 0100 iMJfiO L3? .584 MNEHflm' $3” ”$03 2200 2250 IL Table F-31 Anal sis for T for Right and Table F-32 W "Mam. ("J 01 (A (ble F-31 yalysis for Gender Effect on Percent of Cycle in Support and Nonsupport g! Right and Left Leg. GENDER F n 5011-: Few; (2,21 5101047 1.95 .5504 1110777 40.000 45.250 LEFT 42.500 40.250 WT 1.955 $04 111547 00.000 50.750 LEFT 57.500 59.750 lble F-32 ialysis for Gender Effect on Total Percent of Cycles in Support and unsupport. F 71 TM FEW-E 71,37 QPHRT 822% 0000 008 .E54 IHGUHRT 1775 1200 Table F-33 Analysis of Ste of Leg Segments for Each Leg. 575 0105191 777017 1.1 777701 37.7 11 9191' 29.1 17 F007 25.1 71 2,7 WISH 27.51 1:9 W 72.29 744 F011 31qu 141 1.7 711707 9.91 111 W 14.54; 110; ”I" 20.41; 1257 (.1 5707 17.134 7227 W 19.509 1247 7017 25.910 132) T . ll :1”de (0 Take: "£18011 t0 (lining 254 1le Ffl33 gysis of Stage Effect on Linear Dispjacement (cm) of Centers of Mass Leg Segments for Selected Periods During One Complete RunninLCycle 'WEach Leg. 577105 1 2 3 4 L018 SIDE R L R 1 71 1 11 L p 17518177 80.0 93.5 97.0 107 70.21 .I* 7111811 37.802 30.982 47.221 41.071 37.708 37.003 43.712 41.829 2.12 .353 747111 7401 7501 7441 7391 751 7411 7391 8141117 29.173 31.978 30.009 30.305 25.800 24.311 27.913 28.484 3.23 .2550 7301 7401 7391 7321 7201 7251 7201 7271 7001 25.112 20.028 28.407 24.083 20.538 17.150 17.512 19.259 15.01 .0038 7311 7331 7301 7201 7211 7181 7101 7181 .14 7171817 27.580 27.230 28.070 21.400 38.320 40.320 55.080 02.870 0.52 .7728 7341 7341 7311 7231 7391 7411 7521 7581 5114117 32.290 31.020 35.290 24.200 43.950 41.090 00.100 09.050 0.70 .0910 7401 7391 7381 7201 7451 7431 7021 7051 7007 34.920 34.180 30.040 23.220 43.780 41.730 08.010 70.710 0.04 .7171 7431 7421 7391 7251 7451 7431 7041 7001 1' 717181 8.915 11.431 18.009 28.299 23.115 30.799 30.274 22.990 0.08 .0901 7111 7141 7201 7301 7241 7321 7281 7211 51141.17 14.501 14.850 25.912 38.070 30.218 39.940 43.352 31.020 1.22 .5149 7181 7181 7281 7411 7311 7411 7401 7291 7007 20.412 21.290 35.414 49.890 39.192 51.700 59.108 42.000 1.27 .5034 7251 7201 7381 7531 7401 7531 7551 7391 E 711181 17.330 14.319 22.449 10.095 28.110 21.790 31.517 27.210 0.48 .7924 7221 7181 7241 7171 7291 7221 7291 7251 5114114 19.508 10.471 23.405 17.934 33.030 22.517 31.791 27.080 0.42 .8252 7241 "7201* *7 7251 7191 7341 7231 7301 7251 7087 25.910 22.490 27.090 23.700 42.530 25.720 34.130 34.590 0.31 .8870 1321 7281 7301 7251 7441 7201 7321 1321 111 = Percent of standing height. = Touchdown to Takeoff. = Takeoff to Mini-um Knee Angle. = Hinilun Knee Angle to Maxi-7171 Thigh Segaent Height. = liaxilua Thigh Segment Height to Tmchdom. Table F-34 w W for Each Le 6801 (1T8 TETBH 3.1 THIGH 7007 4.1 THIGH Table F-34 1nalysis of Gender Effect on Linear Displacement 255 (cm) of Centers of Mass 1f Leg Segments for Selected Periods During One Complete Running Cycle Ior Each Leg. GENDER ME (:81nt L188 SIDE R L R L p (EIGHT 96.2 93.2 (2.2) 1.! THIGH 42.856 44.178 40.369 34.565 6.49 .1335 (44)“ (46) (43) (37) 51M 32. 575 32. 423 27.173 25.116 5. 35 .1574 (34) (34) (30) (27) FOOT 25.126 23.830 20.689 19.730 17.81 .0532 (26) (25) (22) (21) 2* THIGH 41.691 41.950 33.436 33.990 0.34 .7484 ME (M) (M) 1%) 81M 49.715 46.670 39.098 36.910 0.52 .6572 (52) (48) (42) (40) F007 51.740 48.980 39.930 35.940 0.63 .6151 (54) (51) (43) (38) &! THIGH 18.286 22.581 22.201 24.182 0.17 .8515 (19) (23) (24) (26) STM 26.707 30.563 30.314 31.683 0.17 .8579 (28) (32) (32) (34) FIXIT 36.405 41.490 40.658 40.950 0.13 .H (38) (43) (44) (44) L! THIGH 27.896 23.808 21.821 15.899 1.33 .4283 (29) (25) (23) (17) SHAW 29.903 23.667 24.264 18.337 0.75 .5727 5D (5) HM (N) F087 35.977 28.846 29.157 24.410 0.23 .8102 (37) (30) (31) (26) 1. = Touchdown to Takeoff. H = Percent of standing height. 2. = Takeoff to Hinilun Knee Angle. 3. = inilun Knee Angle to l'iaxioun Thigh Segment Height. 4- = ilun Thigh Segment Height to Touchdom. Table F-35 Analysis of Leg Segment: Each Leg. SITE U18 SIDE R 1.1 01181 -45.. (0.1 91118 49.1 (-0.( mm 43.5 (-1.2 230081 53.2 (0.9 W 99.81 [-0.31 FWT 9,55 (0.16 3-1 111189 21.78 256 Table F—35 Analysis of Stage Effect on Angular Displacement in Degrees (Radians) of Leg Segments for Selected Periods During One Complete Running Cycle for Each Leg. STAE 1 2 3 4 F L188 SIDE R L R L R L R L (6.2) 1.! THIGH -45.626 -34.907 -49.909 -44.523 -56.233 -45.051 -fi.664 -57.036 1.358 .4823 (0788) (0.610) (0.870) (0.778) (-0.983) (-0.785) H.006) (0994) (1.314) (.4926) SIM ~49.816 -47.399 -54.567 53.905 50.009 -52.150 -46.641 -43.747 0.180 .9568 (-0.869) (4.1.828) 00.952) (-0.910) (-0.872) (-0.910) 00.814) (-0.764) (0.303) (.8922) FUJI -73.550 -68.250 -81.580 89.650 -62.250 ’69.280 -93.950 -82.630 0&3 .6175 H.282) H.190) H.424) H.563) H.146) H.210) H.640) H.442) (0.500) (.7842) 2.! THIGH 53.210 43.260 44.800 27.790 43.650 39.430 60.830 61.280 1.074 .5556 (0.928) (0.756) (0.725) (0.485) (0.762) (0.688) (1.058) (1.070) (1.195) (.5520) SIN -l9.850 ~15.540 -15.070 -36.280 -41.750 -23.330 ~21.910 -31.900 0.550 .7584 (-0.346) (—0.271) (-0.262) (-0.633) (-0.730) (0.408) (-0.380) (-0.200) (0.291) (.8988) FIBT 9.650 ~61.270 -10.110 -21.340 -55.070 -26.320 6.050 -6.560 0.987 .5821 (0.168) H.070) (-0.176) (-0.372) (-0.971) (-0.460) (0.106) (-0.116) (0.991) (.5811) 1.! THIGH 21.788 15.160 22.787 41.930 31.115 32.030 19.514 26.780 0.371 .8538 (0.348) (0.265) (0.398) (0.732) (0.542) (0.484) (0.340) (0.468) (0.357) (.8618) 8114844 37.710 41.000 50.850 60.210 53.540 60.730 68.770 55.330 0.403 .8362 (0.658) (0.417) (0.882) (1.050) (0.935) (1.058) (1.198) (0.965) (0.389) (.8436) FOOT 38.320 49.700 67.790 72.950 71.960 83.670 78.600 64.780 0.413 .8304 (0.668) (0.866) (1.184) (1.274) (1.56) (1.464) (1.366) (1.130) (0.423) (.8251) J 18188 -27.239 -27.466 ~21.778 -12.713 -20.397 -15.702 -l9.062 ~2l.036 0.544 .7615 (0475) (-0.479) (-0.380) (-0.223) (0&6) (-0.275) (0333) (-0.368) (0.554) (.7615) 88188 32.910 26.460 16.750 22.550 45.790 14.770 7.480 20.580 0.815 .6825 (0.574) (0.462) (0.292) (0.394) (0.764) (0.258) (0.130) (0.359) (0.872) (.6215) FCKJT 30.330 31.770 15.930 43.520 60.790 17.850 6.870 30.130 0.709 .6852 (0.530) (0.554) (0.280) (0.760) (1.062) (0.314) (0.120) (0.526) (0.705) (.6871) l. = Touchdom to Takeoff. NOTE: Negative number indicates clockwise 2. = Takeoff to Minimum Knee Angle. movement of segment. 3. = Hinimun Knee Angle to Haxinuo Thigh Segment Height. Positive number indicates counter- 4- = Hexinun Thigh Segment Height to Touchdown. clockwise mveoent of sequent. Table F-36 Analysis of of Leg Segme ELEM L111) 2.! I 3.! m 4.. m1 257 Table F-36 Analysis of Gender Effect on Angular Displacement in Degrees (Radians) of Leg Segments for Selected Periods During One Complete Running Cycle for Each Leg. EMER (WI PERI F p LIHB SIDE R L R L (2.2) Li THIBH -51.036 46.822 -53.498 43.936 0.133 .8827 (~0.890) (-0.816) (-0.934) (-0.767) (0.124) (.8894) 58885 -49.722 -53.098 -50.745 -45.502 3.599 .2174 (-0.868) (~0.912) (-0.886) (-0.794) (4.346) (.1870) FWT -76. 969 -90.550 -78. 693 -64.360 2.847 .2599 (-1.343) (-1.580) (-1.402) (-1.122) (2.589) (.2787) THIGH 58.656 49.640 42.5% 36.240 4.482 .1824 (can) (08H9 (088) WJKH (45%) (A8”) SHANK -16.890 -11.930 -32.390 -41.600 1.882 .3470 6025) 002%) 805%) (05m) (083) 66M” FEET -3. 780 -21.960 -20.950 -35.790 0.876 .5329 (0071) (-0.384) (-0.366) (-0.625) (0.867) (.5356) THIGH 20.151 24.960 27.451 32.990 0.934 .5171 (0.351) (0.423) (0.463) (0.551) (0.643) (.6088) SHAHK 44.929 51.940 60.504 56.690 1.122 .4713 (0.781) (0.905) (1.055) (0.989) (1.102) (.4757) MIT 64. 090 66. 370 64. 240 69.180 0. 005 .9951 UJKH HAHN (an (can) (008) L958 THIGH -26.297 -20.601 -17.942 -17.858 1.683’ .3727 (-0.458) (-0.360) (-0.314) (-0.312) (1.680) (.3731) SHANK 26.030 11.210 25.430 30.970 1.394 .4178 (0.437) (0.195) (0. 443) (0.541) (1.495) (.4008) FGDT 19.760 22.320 37.222 39.310 0.652 .6054 (0.345) (0.390) (0.651) (0.686) (0.654) (.6047) 4 1. = Touchdown to Takeoff. NDTE: Negative number indicates clockwise 2. = Takeoff to Ninioun Knee Angle. movement of sequent. 3. = ('(inioun Knee Angle to Haxinuo Thigh Segment Height. Positive number indicates comterclockwise 4. = ioua Thigh Segment Height to Touchdown. UOVEHEflt Of sequent. Table F-37 Analysis for M STAGE LIN) SIDE 1 (£180 (3 ((881114 27. (3 m Table F-3g Anal sis far 8 “MW \ SEWER IIHB SIDE (£180 \ ((18108 ((8881 m 258 Table F—37 Analysis for Stage Effect on Forward—Backward Swing Linear Displacement (cm) of Centers of Mass of Arm Segments. N (rd 4 erase 1 L188 SIDE n L R L n L R L F p HEIGHT 80.6 93.5 97.6 107 (6,2) HUHERUS 30.37 53.36 49.35 56.23 57.11 47.84 62.77 68.24 0.519 .7745 (38)! (66) 1531 (60) (58) 149) 1591 (64) FDREARH 27.10 54.29 41.76 51.10 45.57 47.05 49.00 57.44 0.220 .9373 1341 (67) 1451 1551 147) (48) (46) (541 f = Percent of standing height. Table F-38 Agalysis for Gender Effect on Forward-Backward Swing Linear Displacement (cm) Centers of Mass of Arm Segments. GENDER HALE FEHALE 1188 8106 R L R L p HEIGHT 96.2 93.2 12,2) HUHERus 51.945 57.460 47.855 55.370 0.088 .9195 15411 (60) 151) 159) FOREARH 43.513 51.670 38.201 53.270 0.123 .8908 1411 1571 (45) (54) L f = Percent of standing height. Table PM W W SHE UM SIDE R HERE -75.550 (1.268) W -15.118 {-0.264} flute: '-' = tlockuise iSiqnificant for righ Table F-40 3% \ SEWER UHF SIDE \ lllERUS FM Table F-39 Analysis for Stage Effect on Forward-Backward Swing Angular Displacement in Degrees (Radians) of Arms. STABE 1 2 3 4 F p LIHB SIDE R L R (6,2) HUHERUS -75.550 -78.570 -57.300 ~70.720 ~46.960 -64.540 *119.180 -104.410 0.343 .8690 (1.268) (-1.352) (-1.014) (-1.214) (-0.894) (~1.122) (-2.074) (-1.822) (0.353) (.8639) PM -15.118 -55.840 402.370 0.330 -76.082 -76.670 442.200 '109.150 18.273 .0528! (-0.264) (-0.976) (-1.786) (0.006) (-1.330) {-1.338) (~2.536) (-l.930) (14.062) (.0679) Note: '-' = clockwise rotation of liab segment leasured frol the distal end. I Significant for right forearm. 1 _2_§_ 1 Table F-40 Analysis for Gender Effect on Forward~Backward Swing_Angular Displacement in Degrees (Radians) of Arms. GENDER HALE FEME 1: p LIHB SIDE 11 L R L 12,21 MERLE -74.000 -73.190 -75.000 -85.930 0.465 .6824 H.335) H.268) 11.2901 11.4871 10.5951 1.62681 Fm 448.947 68.440 48.938 452.220 1.234 .4476 (‘1.553) (~1.196) (-1.405) (-0.924) (0.589) (.6293) H712: = clockwise rotation of 11.5 sequent leasured 1m. the distal end. BIBLIOGRAPHY hmano, Y.. Mizuta running of 58 Kobayashi (Ed. Biomechanics V 01biomechanic Publisher. (1105, L. B. (1937 the human infa hmes, L. B. (1966 the American f \ Atwater, A. E. (1 (111. Haven (E1 m Health. Atwater, A. E., I Kinematic aspt ”(AM Ra1191. N. 11935 three years. 1 (Mm, ”“11 N- D. 1196 W University 13 BEfnstein’ N. (1 York: PErqamo Brainerd! C. (19 “W7. The E1 (1111111611I B. R. and “mm Bibliography Amano, Y., Mizutani, S., & Hoshikawa, T. (1983). Longitudinal study of running of 58 children over a four-year period. In H. Matsui & K. Kobayashi (Ed.). International series on biomechanics, Volume 48, Biomechanics VIII-B, Proceedings of the eighth international congress of biomechanics (pp. 663-668). Champaign, 111.: Human Kinetics Publisher. Ames, L. B. (1937). The sequential patterning of prone progression in the human infant. Genetic Psychological Monographs, 12, 409-460. Ames, L. B. (1966). Individuality of motor skill development. Journal of the American Physical Therapy Association, 49 (2). 122-127. Atwater, A. E. (1980). Kinematic analysis of sprinting. In J. M. Cooper & B. Haven (Eds.). Proceedings fo the boyggghanics symposiumgglndiana University, October 26-28, 1980 (pp. 303-314). Indiana State Board of Health. Atwater, A. E., Morris, A. M., Williams, J.M., & Nilmore, J. H. (1981). Kinematic aSpects of running in 3- to 6-year-old boys and girls. International Journal of Sports Medicine, 5 (2), 282-283. Bayley, N. (1935). The development of motor abilities during the first three years. Monograph of the Society for Research on Child Development, 1, 1-26. Beck, M. C. (1965). Theypath of the center of gravity during running in boys, grades one to six. Unpublished doctoral dissertation, University of Nisconsin. Bernstein, N. (1967). The co-ordination and regulation of movements. New York: Pergamon Press. Brainerd, C. (1978). The stage question in cognitive-developmental theory. The Behavioral and Brain Sciences, 2, 173~213. Brandell, B. R. (1973). An analysis of muscle coordination in walking and running gaits. In S. Cerquiglini, A. Venerando, & J. Nartenweiler (Eds.). Medicine and sport, Vol. 8: Biomechanics III (pp. 278-287). Baltimore: University Park Press. Branta, (3., HanE Relationshi o the preschool annual confere- Sport and Phys Branta, (3. F., Ki1 uue£_eecie£euu National Conve1 Education, Rem Druer, ('1. R. (197' Philadelphia: I Brown, E. )1. (1971 girls three to University of l Burnside, L. H. (. Carpenter, n. (19. General motor . 11.444-465. cavanagh! PI Re, I CODDirison of 1 “”“591 F- c. 1191 fitfluflflfflitteeu “‘VEFSItv of 1 Cunningham, B. (1, d”Nonment of W911 191 Di) "flnte, A” FUt training and a Whiting. In 3. Medicine and 5 “(Warm Uni‘ Death, D. F. (195] (Iron h Six ea University of l DEShon' D. E 8, N Sprint r(InningE 261 Branta, C., Haubenstricker, J., Kiger, J., & Ulrich, B. (1984). Relationship of qualitative and quantitative motor performance during the preschool and elementary school years. Paper presented at the annual conference of the North American Society for the Psychology of Sport and Physical Activity. Eugene, Oregon. Branta, C. F., Kiger, J. E., & Yager, M. A. (1985). Profiles of the motoryperformance of preschool age children. Paper presented to the National Convention of the American Aliance of Health, Physical Education, Recreation and Dance. Atlanta, Georgia. Broer, M. R. (1973). Efficiencyyof human movement (4rd ed.). Philadelphia: N. B. Saunders, Co. Brown, E. W. (1978). Biomechanical analysis of the running patterns of girls three to ten years of age. Unpublished doctoral dissertation. University of Oregon. Burnside, L. H. (1927). Coordination in the locomotion of infants. Genetic Psychological Monographs, 2 (5). 238-372. Carpenter, A. (1942). The measurement of general motor capacity and general motor ability in the first three grades. Research Quarterly, Li, 444-465. Cavanagh, P. R., Pollock, M. L.,& Landa, J. (1977). A biomechanical comparison of elite and good distance runners. Annuals of the New York Academy of Science, 301, 328-345. Clouse, F. C. (1959). A kinetic analysis of the development of The [ggning pattern of preschool boyg) Unpublished doctoral dissertation, University of Wisconsin. Cunningham, B. (1927). An eXperiment in measuring gross motor development of infants and young children. Journal of Educational stchoiogy, 1.2. 458-464. Dal Monte, A., Fucci, 8., & Manoni, A. (1973). The treadmill used as a training and a simulator instrument in middle- and long-distance running. In S. Cerquiglini, A. Venerando, & J. Nartenweiler (Eds.). Uggicine and sport, Vol. 8: Biomechanics III (pp. 359-363). Baltimore: University Park Press. Deach, D. F. (1951). Genetic development of motor skills of children two LhEough six years of age. Unpublished doctoral dissertation, University of Michigan. Deshon, D. E. & Nelson, R. C. (1964). A cinematographical analysis of Sprint running. Research Quarterly, §§(4), 451-455. 1111110, B. (1975). J. F. Keogh (Eds 193-216). New Yc Dittmer, J. (1962). running pattern Unpublished mast 015011. 6. H. 8. 111 of London Press. Early Childhood Mot 0.1m mum. Tabul, Psychology, and lansing. Dliutt, B. C. 6 B overground and . Erikson, E. H. (19 Espenschade, A. (1 (£11.), M York: Harper 8‘ .‘ Espenschade, A. S. Cfllumbus’ Ohio: Farm, (1). U. (1930) changes in run" Penn, (1). D. (1931) ML B21 34 Fortney1 v. L. (19 W. (Urtney’ v' L. ( attern of tho- ductoral disse, Fountain, (3. D l '9 1 19811. 33% childI'en 2 112. m unvention, Chi 262 Dillman, C. (1975). Kinematic analysis of running. In J. H. Wilmore & J. F. Keogh (Eds.). Exercise and sport sciences reviews: Vol. 3 (pp. 193-218). New York: Academic Press. Dittmer, J. (1962). A kinematic analysis of the development of the running pattern of grade school girls and certain factors which distuinguish_good from poor performances at the observed ages. Unpublished masters thesis, University of Wisconsin. Dyson, G. H. G. (1973). The mechanics of athletics. London: University of London Press, Ltd. Early Childhood Motor Skills Development Study (1985). Standards of performance on selected fundamental motor skills for preschool age children. Tabulated data. School of Health Education, Counseling Psychology, and Human Performance. Michigan State University, East Lansing. Elliott, B. C. & Blanksby, B. A. (1976). A cinematographic analysis of overground and treadmill running by males and females. Medicine in Science and Sports. Q (2), 84-87. Erikson, E. H. (1963). Childhood and society, New York: Norton. Espenschade, A. (1960). Motor development. In W. R. Johnson (Ed.). Science andggedicine of exercise and sport (pp. 419-438). New York: Harper & Brothers. 1 Espenschade, A. S. & Eckert, H. M. (1980). Motor Develgpment (2nd.ed.). Columbus, Ohio: Charles E. Merril. Fenn, W. D. (1930). Work against gravity and work due to velocity changes in running. American Journal of Physiology, 9;, 433-462. Fenn, W. D. (1931). A cinematographic study of sprinters. The Scientific Monthly, 3;, 346-354. Fortney, V. L. (1964). The swinging limb in running of boys ages seven through eleven. Unpublished masters thesis. University of Wisconsin. Fortney, V. L. (1980). The kinematics and kinetics of the running flattern of two-, four-, and six-year-old children. Unpublished doctoral dissertation, Purdue University. Fountain, C. D., Ulrich, B. D., Seefeldt, V. D., & Haubenstricker, J. L. (1981). Relationship of developmental_stages and running velocity in ghildren 2 1/2-5 years of age. Paper presented at American Alliance of Health, Physical Education, Recreation, and Dance Midwest District Convention, Chicago. Frederick, four, an Indiana Freud, S. ( Trans.). 1905.) Gardner, H. ed.). Bos Barrett, 6. NAPECU/NC Office of Circle. Gesell, A. ( Gesell, A. (1 W Gesell, A. (1 Brothers. Massow, R, 3 Me “111%., Wisconsin, (3135501,. R- 3. 14. m Bfldfrey' B. 8, Ne" York: A Duruzhanin. 9. man. 814m GFDVEs, R. & Philadfiphi. buttridge, H. l y means Of L0. 107~2e6. ”MW". . E children. Du. I‘J 0* (A Frederick, S. D. (1977). Performance of selected motor tasks by three, four, and five year old children. Unpublished doctoral dissertation, Indiana University. Freud, S. (1962). Three contributions to the theory of sex (A. A. Brill, Trans.). New York: E. P. Dutton. (Original work first published in 1905.) Gardner, H. (1982). Developmental psychology, An introduction (2nd. ed.). Boston: Little, Brown and Company. Barrett, G. E. (1978). Developmental biomechanics. In Proceedings of the NAPECW/NCPEAM National Conference (pp 156-159). Denver, Colorado: Office of Publication Services, University of Illinois at Chicago Circle. Gesell, A. (1928). Infancy and human growth. New York: Macmillian Co. Gesell, A. (1939). Reciprocal interweaving in neuromotor development. The Journal of Comparative Neurology, 1 (2). 161-180. Gesell, A. (1948). Studies in child development. New York: Harper & Brothers. Glassow, R. 8., Halverson, L. E., & Rarick, G. L. (1965). merovemegt of motor development and physical fitness in elementary school children. Cooperative Research Project #696. Madison: University of Wisconsin. Glassow, R. B. & Kruse, P. (1960). Motor performance of girls age 6 to 14. Research Quarterly, §113), 426-433. Godfrey, B. & Kephart, N. (1969). Movement patterns and motor education. New York: Appleton-Century-Crofts. Gorozhanin, V. S. (1973). Investigation of the kinematics of running in man. Bigphysics, LB, 1177-1181. Groves, R. & Camaione, D. N. (1983). Concepts in kinesiology (2nd. ed.). Philadelphia: Saunders College Publishing. Guttridge, M. V. (1939, May). A study of motor achievements of young children. Archives of Psychology, 241, 1-178. Halverson, H. M. (1931). An experimental study of prehension in infants by means of systematic cinema records. Genetic Psychology Monographs, 1g, 107-286. Halverson, L. E. (1966). Development of motor patterns in young children. Quest, p, 44-53. Halverson, L. Hopping ov: (luarterl 1 Hanson, J, B. sprint runn University Haubenstricker validation 1 Paper preser Society for Lansing, Mic Haubenstricker, A. (1984). Q Mum Midwest Dist, Education, R1 Haubenstricker, ”Aim Paper present Health, Physi Minnesota. Haubenstricker, W c("ll/Ention of Health, PhYSll “41.11. 8. (1985) E"Ulewood [31,, HPYHbod’ K. M. (1 Human Kinetics 264 Halverson, L. a Williams, K. (1985, March). Developmental sequences for Hopping over distance: A prelongitudinal screening. Research Quarterly for Exercise and Sport, pp111, 37-44. Hanson, J, B. (1975). A kinematic analysis of the support_phase of sprint running in selected individuals. Unpublished masters thesis, University of Wisconson. Haubenstricker, J., Branta, C., & Seefeldt, V. (1983). Preliminany validation of developmental sequences for throwing and catching. Paper presented at the annual conference of the North American Society for the Psychology of Sport and Physical Activity. East Lansing, Michigan. Haubenstricker, J., Branta, C., Ulrich, E., Brakora, L., & E-Lotfalian, A. (1984). Quantitative and qualitative analysis of jumping behavior in young children. Paper presented at the annual convention of the Midwest District of the American Alliance of Health, Physical Education, Recreation and Dance. Indianapolis, Indiana. Haubenstricker, J., Seefeldt, V., a Branta, C. (1983). Preliminacy validation of a deveIOpmentaI sequence for the standing long jump. Paper presented at the annual convention of the American Alliance of Health, Physical Education, Recreation and Dance. Minneapolis, Minnesota. Haubenstricker, J., Seefeldt, V., Fountain, C., & Sapp, M. (1981). A developmgntal sequence for kicking, Paper presented at the annual convention of the Midwest District of the American Alliance of Health, Physical Education, Recreation and Dance. Chicago, Illinois. Hay, J. G. (1985). The biomechanics of sports technigges (3rd. ed.). Englewood Cliffs, N. J.: Prentice-Hall, Inc. Haywood, K. M. (1986). Life span motor development. Champaign, Ill.- Human Kinetics Publishers. Hellebrandt, F. A., Rarick, L. G., Glassow, R. E., & Carns, M. L. (1961). Physiological analysis of basic motor skills: 1. Growth and development of jumping. American Journal of Physical Medicine, mp11) 14-25. Hinrichs, R. N., Cavanagh, P. R., & Williams, K. R. (1983). Upper extremity contributions to angular momentum in running. In H. Matsui & K. Kobayashi (Eds.). International series on biomechanics, Volume 48, Biomechanics VIII-B. Proceedings of the Eighth International Qgggress of Biomechanics Nagoya, Japan (pp. 641-647). Champaign, lll.: Human Kinetics Publishers. Hogberg, P. (1952). Length of stride, stride frequency, ‘flight' period and maximum distance between feet during running with different speeds. Arbeitsphysiologie, 13, 431-436. Holstein, C. B. development-o females. DEL Hupper, B. J. (1 Track Technig Hushikaua, T., M pattern in re Volume 8: Bio Press. Housden, F. (196 Hill (Ed.). R and Field New James, S. L. 2, 8 Wm James, S. L. k B aspects of ru sciences revi \— (enkins, L. M. ( (“New Publications, JDhnsun, R. p. ( 01 elementary (90111.1. 119651 A'lUEles: Dapa (”“1991 L. 119 moral order. W1 (1, 11 Kurakin, M. (197 M1 3‘ (l 1972). Kurtines, H. & E Evie" and ev Lat”“911. H. . (19: flth and sj LErnEr, M. (197: um“) Chlldre "We’Sitv. 1 265 Holstein, C. B. (1976). Irreversible, stepwise sequence in the development of moral judgement: A longitudinal study of males and females. Child Development, 41, 51-61. Hopper, B. J. (1964, September). The mechanics of arm action in running. Track Technique, Ll, 520-522. Hoshikawa, T., Matsui, H., & Miyashita, M. (1973). Analysis of running pattern in relation to speed. In E. Jokl (Ed.). Medicine and sport, Volume 8: Biomechanics III (pp. 342-348). Baltimore: University Park Press. Housden, F. (1964). Mechanical analysis of the running movement. In F. Wilt (Ed.). Run,run,run (pp. 240-242). Los Altos, California: Track and Field News, Inc. James, S. L. & Brubaker, C. E. (1972, August). Running Mechanics. Journal of the American Medical Association, 221, 1014-1016. James, S. L. & Brubaker, C. E. (1973). Biomechanical and neuromuscular aspects of running. In J. H. Wilmore (Ed.). Exercise and sport sciences reviews: Vol. 1 (pp. 189-216). New York: Academic Press. Jenkins, L. M. (1930). A comparative study of motor achievements of children five, six, and seven years of age. New York: Bureau of Publications, Teachers College, Columbia University. Johnson, R. D. (1962). Measurement of achievement in fundamental skills of elementary school children. Research Quarterly, §§, 94-103. Keogh, J. (1965). Motoryperformance of elementary school children. Los Angeles: Department of Physical Education University of California. Kohlberg, L. (1963). The development of children's orientations toward a moral order. I Sequence in the development of moral thought. Vita Humana, p, 11-33. Kurakin, M. (1973). Relationships among running parameters. Yessis Reviews, §_(1), 1-4. (Originally published in Track and Field, 4, 15, 1972). Kurtines, W. & Greif, E. (1974). The development of moral thought: Review and evaluation of Kohlberg’s approach. Psychological Bulletin, BL 18), 453-470. Latchaw, M. (1954, December). Measuring selected motor skills in fourth, fifth, and sixth grades. Research Quarterly, 2:, 439-449. Lerner, H. (1975). Performance of selected fundamental motor skills by ZQQng children. Unpublished masters project. Michigan State University. East Lansing, Michigan. LuManen, P. R speed. In E. Park Press. hum R. A. b H sprinting. J Nun,R. V. (19 Science in S harey, E. J. (1 D. Appleton Huon, R. B. (1 parameters 1 dissertatior HcCaskill, C. l uhievementr MDlenaghan, 3 music HcBraH, M. p. Appleton-Ce Mersereau, M. “New UDPUblished Mersereau, M. BIE§§§._gg BHLlflflfligg dissertatio HitlerI D. (,9 future hold 229~236. (1111”1 1). & D aim. r (Tiller, 5': Ha e"(Al’fllance cnnVEntIOn and RECreai Miyamaru’ B. ‘ FUnning pal BiomeChani1 Inkyg, KYr1 266 Luhtanen, P. a Komi, P. (1978). Mechanical factors influencing running speed. In E. Asmussen (Ed.). Biomechanics VI-B. Baltimore: University Park Press. Mann, R. A. & Hagy, J. (1980). Biomechanics of walking, running, and sprinting. Journal of Sports Medicine, §_(5), 345-350. Mann, R. V. (1981). A kinetic analysis of sprinting. Medicine and Science in Sports and Exercise, L§_(5), 325-328. Marey, E. J. (1895). Movement (E. Pritchard, Trans.). New York: D. Appleton & Company. Mason, R. B. (1980). A kinematic and kinetic analysis of selected parameters during the support phase of running} Unpublished doctoral dissertation. University of Oregon, Eugene. McCaskill, C. L. 6 Wellman, B. L. (1938). A study of comon motor achievements at the preschool ages. Child Development, 9, 141:150. McClenaghan, B. A. a Gallahue, D. L. (1978). Fundamental movement: A developmental approach. Philadelphia: W.B. Saunders Co. McGraw, M. B. (1935). Growthg A study of Johnny_and Jimmy. New York: Appleton—Century. Mersereau, M. R. (1974). A cinematographic analysis of the developmemnt of the running pattern of female infants at 22 and 25 months of age. Unpublished masters thesis, Purdue University. Mersereau, M. R. (1977). The relationship between measures of dynampg pppcess, outputg and dynamic stability in the development of running and jumpinqppptterns of pre-school age females. Unpublished doctoral dissertation, Purdue University. Miller, D. (1981, December). Biomechanics of running - What should the future hold? Canadian Journal of Applied Sport Science, §(4), 229-236. Miller, D. 6 Nelson, R. (1973). The biomechanics of sport - - A research approach. Philadelphia: Lea and Febiger. Miller, S., Haubenstricker, J., & Seefeldt, V. (1977). Standards of performance in selected motor skills. Paper presented at the annual convention of the Michigan Association for health, Physical Education and Recreation. Dearborn, Michigan. Miyamaru, G. (1976). Development of motor pattern in preschool boys, running pattern and jumping pattern. In Japanese Society of Biomechanics (Eds.). Science of human movement (Vol. 2, pp. 96-114). Tokyo: Kyroin Book Company Ltd. Hmris, A. “-1 September). 6 year old 1 hubridge, E. Publicat1on1 Huybridge, E.‘ Dover Publi1 NHsun, R., D1 BlOHECHflnlCT Science in 1 Nelson, R. b 61 running. 3g; Nmthrip, J. W uuui_ueiiel Piaget. J. 119. proceedings StUdY Group 1965. In J. Baaleeeeet Universitie Piaget. J. 119 Béflflél_gj_g; h00.1. E. (1 Unpublished HEELSD_Ebymp In lication mm; Roberton, (‘1. A trials: Imp devEl011111th Ruberton' M. A ‘Ed~l. Moto Tincetdfij“ RODertOn’ H. A devalopment °1 motor be (Than Kine); 267 Morris, A. M., Williams, J. M., Atwater, A. E., & Wilmore, J. H. (1982, September). Age and sex differences in motor performance of 3 through 6 year old children, Research Quarterly, 84(3), 214-221. Muybridge, E. (1955). The human figure in motion. New York: Dover Publications, Inc. (Original work published in 1887). Muybridge, E. (1957). Animals in motion (L. S. Brown, Ed.). New York: Dover Publication, Inc. (Original work published in 1887). Nelson, R., Dillman, C., Lagasse, P., & Bickette, P. (1972). Biomechanics of overground verses treadmill running. Medicine and Science in Sports, 4 (4), 233-240. Nelson, R. & Gregor, R. (1976, October). Biomechanics of distance running. Research Quarterly, 41(3), 417-428. Northrip, J. W., Logan, 8. A., a McKinney, W. C. (1983). Analysis of sport mption (3rd. ed.). Dubuque, Iowa: Wm. C. Brown Co. Piaget, J. (1960). The definition of stages of development: in the proceedings of the Fourth Meeting of the World Health Organization Study Group on the Psychobiological Development of the Child, Geneva, 1965. In J. M. Tanner & B. Inhelder (Eds.). Discussions on Child Development (pp. 116-135 in Vol. IV). New York: International Universities Press. Piaget, J. (1983). Piatet's theory. In P. H. Mussen (Ed.). Carmichael's manual of childppsyghology (pp. (03-128). New York: Wiley. Rapp, K. E. (1963). Running_velocity: Body_rise and stride lemgth. Unpublished masters thesis, State University of Iowa. Roberton, M. A. (1972, October). Developmental Kinesiology. Journal of Health Physical Education and Recreation, 4p, 65-66. Roberton, M. A. (1975) Stability of stage categorizations across trials: Implications for the ‘stage theory’ of overarm throw development. Unpublished doctoral dissertation. University of Wisconsin, Madison. Roberton, M. A. (1977). Stability of stage categorizations across trials: Implications for the "stage theory" of overarm throw development. Journal of Human Movement Studies, 4, 49-59. Roberton, M. A. (1978a). Stages in motor development. In M. Ridenour (Ed.). Motor deve10pment: Issues and applications (pp. 63-81). Princeton, N. J.: Princeton Book Company. Roberton, M. A, (1978b). Stability of stage categorizations in motor development. In D. A. Landers & R. W. Christina (Eds.). Psychology of motor behavior and sport - 1977 (pp. 494-506). Champaign, 111.: Human Kinetics Publishers. Rot Robe c B g R) Huber pp Robert seq NEH up Pub: Roberta scre item Sflto, p Ieupo (Eds. m Press. 591. 1. UR) VHF! “3 (nstlt Etlljgpl Uslnstjt, (PM. 198191“, V “1 Realty 59119] ((1 (h 1 V. E Seatt Roberton, M. A. (1982). Describing ‘stages' within and across motor tasks. In J. A. S. Kelso & J. E. Clark (Eds.). The development_pi movement control and co-ordination (pp. 293-307). St. Louis: John Wiley & Sons Ltd. Roberton, M. A. (1984). Changing motor patterns during childhood. In J. Thomas (Ed.). Motor development during childhood and adolencence (pp. 48-90). Minneapolis: Burgess. Roberton, M. A. & Halverson, L. E. (1984a). The developing child-His changing movement. In B. J. Logston, K. R. Barrett, M. Ammons, M. R. Broer, L. E. Halverson, R. McGee, & M. A. Roberton (Eds.). Physical education for children: A focus on the teaching process (pp. 24-67). Philadelphia: Lea & Febiger. Roberton, M. A. & Halverson, L. E. (1984b). Develgping children — Their movement. A guide for teachers. Philadelphia: Lea & Febiger. Roberton, M. A. a Langendorfer, S. (1980). Testing motor development sequences across 9-14 years. In C. H. Nadeau, W. R. Hallwell, K. M. Newell, & G. C. Roberts (Eds.). Psychology of motor behavior and sport - 1979 (pp. 269-279). Champaign, 111.: Human Kinetics Publishers. Roberton, M. A., Williams, K. & Langendorfer, S. (1980). Prelongitudinal screening of motor development sequences. Research Quarterly for Exercise and S ort, 54, 724—731. Saito, M., Kobayashi, K., Miyashita, M., & Hoshikawa, T. (1974). Temporal patterns in running. In R. L. Nelson 8 C. A. Morehouse (Eds.). Biomechanics IV: Proceedings from the fourth international seminar on biomechanics (pp. 106-111). Baltimore: University Park Press. Sapp, M. M. (1980). The development of galloping in young children: A preliminary study. Unpublished masters project. Michigan State University. East Lansing, Michigan. SAS Institute Inc. (1985a). SAS user’s guide: Basics, Version 5 Edition. Cary, North Carolina: Author. SAS Institute Inc. (1985b). SAS user's guide: Statistics, Version 5 Edition. Cary, North Carolina: Author. Seefeldt, V. (1972, March). Developmental sequence of catching skill. Paper presented at the national conference of the American Alliance of Health, Physical Education, and Recreation, Houston. Seefeldt, V. (1974). Definitions of commonly used terms. As developed at the Seattle Conference of Motor Development (July, 1974), Seattle. See (19 Seefeldt, V. & Haubenstricker, J. (1982). Patterns, phases, or stages: An analytical model for the study of developmental movement. In. J. A. S. Kelso & J. E. Clark (Eds.). The development of movement control and co-ordination (pp. 309-318). St. Louis: John Wiley 8 Sons, Ltd. Seefeldt, V., Haubenstricker, J. L., Brown, E. W., 6 Branta, C. F. (1983). Description of anthropometric measurements. Unpublished manuscript, (Laboratory Protocol), Youth Sports Institute, Michigan State University, East Lansing, Michigan. Seefeldt, V., Reuschlein, 5., & Vogel, P. (1972). Sequencing motor skills within the physical education curriculum. Paper presented to the National Convention of the American Association for Health, Physical Education and Recreation. Huston, Texas. Seils, L. G. (1951, May). The relationship between measures of physical growth and gross motor performance of primary-grade school children. Research Quarterly, 22(2), 244-260. Shirley, M. (1931). The first two_years: A study of twenty:five babies, I postural and locomptor development. Minneapolis: University of Minnesota Press. Simonian, C. (1981). Fundamentals of sports biomechanics. Englewood Cliffs, N. J.: Prentice-Hall Inc. Sinning, W. E. & Forsyth, H. L. (1970). Lower limb actions while running at different velocities. Medicine and Science in Sports, g_111, 28- 34. Slocum, D. B. & Bowerman, W. (1962). The biomechanics of running. Clinical Orthopaedics, 2;, 39-45. Slocum, D. B. & James, S. L. (1968, September). Biomechanics of running. Journal of the American Medical Association, 205, 97-104. Smith, S. A. (1977). Longitudinal changes in stride length and stride rate of children running. Unpublished masters thesis, University of Wisconsin. Smoll, F. (1982). Developmental kinesiology: Toward a subdiscipline focusing on motor development. In J.A.S. Kilso & J.E. Clark (Eds.). The develgpment of movement control and coordination (pp 319-354). New York: John Whiley & Sons, Ltd. Stewart, M. J. (1980). Motor skill analysis: An introduction. In C. B. Corbin (Ed.). A textbook of motor development (pp. 42-52). Dubuque, Iowa: Wm. C. Brown. Uli Ulr U111 1111, , Ru\n Inc. ”01111111 Rtau Ulibarri, V. D. (1984). An introduction to high-speed cinematographic procedures and analysis...or...You ought to be ingpictures. Manuscript submitted for publication. Ulrich, D. A. (1985). Test of Gross Motor Develgpment. Austin, Texas: Pro.ed. Vilchkovsky, E. S. (1972). Motor development in preschool children and school age children. Theory and Practice of Physical Culture, 6, 29-33. Vilchkovsky, E. S., Dreshchuk, S. A., 6 Shpitalny, V. B. (1973). Investigation of running in preschool children. Theory and Practice of Physical Culture, 2, 40-41. Walton, J. S. (1970). A template for locating segmental centers of gravity. Research QuarterLy, 44 (4), 615-618. Way, D., Haubenstricker, J., 6 Seefeldt, V. (1979). Performppce standards of selected motor skills for_primary grade children. Unpublished manuscript. Michigan State University. East Lansing, Michigan. Wellman, B. L. (1937, March). Motor achievements of preschool children. Childhood Education, 42(7), 311-316. Wickstrom, R. L. (1975). Developmental kinesiology: Maturation of basic motor patterns. In J. F. Wilmore 6 J. F. Keogh (Eds.). Exercise and sport sciences reviews: Volume 4 (pp. 163-192). New York: Academic Press. Wickstrom, R. L. (1983). Fundamental motor patterns (3rd. Ed.). Philadelphia: Lea 6 Febiger. Wild, M. R. (1938, October). The behavior pattern of throwing and some observations concerning its course of development in children. Research Quarterly, 2(3) 20-24. Williams, R. K. (1985). Biomechanics of running. In R. L. Terjung (Ed.). Exercise and sport sciences reviews: Vol. 13 (pp 389-441). New York: Macmillian Publishing Co. Wilt, F. (1964). Fundamental movements in running. In F. Wilt (ed.). Run,run, run (pp. 235-239). Los Altos, Calif.: Track 6 Field News Inc. Wohwill, J. (1973). The study of behavioral development. New York: Academic Press. Bra Keogh, 76- General References Bijou, S. W. (1968, June). Ages, stages, and the naturalization of human development. American Psychologist, 2§_(6), 419-427. Branta, C., Haubenstricker, J., 6 Seefeldt, V. (1984). Age changes in motor skills during childhood and adolescense. In R. L. Terjung (Ed.). Exercise and sport sciences reviews: Vol. 12 (pp. 467-520). Lexington: The Collamore Press. Braune, W. 6 Fischer, 0. (1985). On the center of gravity of the human bogy as related to the equipment of the German infantry soldier (P. G. J. Marquel 6 F. Furlong, Trans.). New York: Springer-Verlag. (Original work Published in 1889). Cavagna, G. A., Saibene, F. 8., 6 Margaria, R. (1964). Mechanical work in running. Journal of Applied Physiology, 43, 249-256. Cavanagh, P. R. 6 Grieve, P. W. (1973). The graphic display of angular movement of the body. British Journal of Sports Medicine, Z, 129-133. Cooper, J. M. 6 Glassow, R. B. (1972). Kinesiology. St. Louis: C. V. Mosby. Corbin, C. 8. (Ed.) (1980). A textbook of motor development. Dubuque, Iowa: Wm. C. Brown. Cretzmeyer, F. X., Alley, L. E., 6 Tipton, C. M. (1969). Bresnahan and Tuttle's track and field athletics. St. Louis: The C. V. Mosby Co. Dempster, W. T. (1955). Space Requirements of the Seated Operator (WADC Technical Report 55-159). Wright Air Development Center, Air Research and Development Command, United Staes Air Force, Wright-Patterson Air Force Base, Ohio. Garrett, R. E., Boardman, T., 6 Garrett, G. E. (1973). Poor man‘s graphics, In S. Cerquiglini, A. Venerando, 6 J. Wartenweiler (Eds.). Medicine and sport, Vol. 8: Biomechanics 111 (pp. 74-83). Baltimore: University Park Press. Garrett, G. E., Reed, W. 8., Widule, C. J., 6 Garrett, R. E. (1971). Human motion: Simulation and visualization. In J. Verdenbregt 6 J. Wartenweiler (Eds.). Biomechanics II (pp 299-303). Baltimore: University Park Press. Keogh, J. (1977). The study of movement skill development. Quest, 28, 76-88. 271 Robert tea 173 Seefel ele Hal bgp Kim Sinclaj Herr Thomas, 1491 Ulibar. up m Hldul E, RTOcs mdule, in ci Kiger, J. E. (1980). A cinematographic analysis of running in kindergarten age children. Unpublished manuscript, Northern Illinois University, DeKalb. Knapp, B. (1977). Skill in sport: The attainment of proficiency. London: Routledge 6 Kegan Paul. March, R. H. (1970). Physics for poets. New York: McGraw-Hill, Inc. Pinard, A. 6 Laurendeauy, M. (1969). “Stages“ in Piaget's cognitive- developmental theory: Exegesis of a concept. In D. Elkind 6 J. Flavell (Eds.). Studies in cognitive development (pp. 121-170). New York: Oxford University Press. Plagenhoeff, S. (1971). Patterns of human motion: A cinematographic analysis. Englewood Cliffs, N. J.: Prentice—Hall, Inc. Rarick, G. L. (1982). Descriptive research and process-oriented explanations of the motor development of children. In J. A. S. Kelso 6 J. E. Clark (Eds.). The development of movement control and coordination (pp 275-292). New York: J. A. Wiley 6 Sons. Ltd. Riley, D. R. 6 Garrett, G. E. (1976). Dynamic interactive computer graphics package for human movement studies. In P. V. Komi (Ed.). International Series on biomechanics, Volume 18, Biomechanics V—B (pp 371-379). Baltimore: University Park Press. Roberton, M. A. (1977). Motor stages: Heuristic model for research and teaching. Proceedings of NAPEW/NCPEM National Conference (pp. 173-180). Orlando, Florida. Seefeldt, V. (1980). Developmental motor patterns: Implications for elementary school physical education. In C. H. Nateau, W. R. Hallwell, K. M. Newell, 6 G. C. Roberts (Eds). Psychology of motor behavior and sport - 1979 (pp. 314-323). Champaign, Ill. : Human Kinetics Publishers. Sinclair, C. B. (1973). Movement of the young child. Columbus: Charles Merrill Co. Thomas, J. (Ed.) (1985). Motor development during childhood and adolescence. Minneapolis: Burgess. Ulibarri, V. D. (1974). A cinematographical analysis of mechanical and anthrppometric characteristics of highly skilled and average skilled female sprinters. Unpublished masters' thesis. Purdue University. Widule, C. J. (1976, May). Segmental moment of inertia scaling procedures. Research Quarterl , 41_(2), 143-147. Widule, C. J. 6 Gossard, D. C. (1971, March). Data modeling techniques in cinematographic research. Research Quarterl , 42, 103-111. 273 Widule, C. J. 6 Gossard, D. C. (1973) Data modling techniques in cinematographic - biomechanical analysis. In S. Cerquiglini, A. Vereranda, 6 J. Wartenweiler (Eds.). Medicine and sport, Vol. 8: Biomechanics 111 (pp. 108-115). Baltimore: University Park Press. Winter, D. (1979). Biomechanics of human movement. New York: John Wiley and Sons. 11111111111111