Z. , 3.1.3:. .1... u. . Q . K, . imp"... J? a?” 5 . .5: z . v. _ . H15 . $1,“. .3, , rm, L w} L .GW.‘ . ”64,... 1...: 2.59.2... f. is... . sniff"... .x “w . =65.“ 4.43.19 . n. . 5...... . «2.1.... ”final. .3 .. 1‘ . . ‘4: I: 4’ .Uksxnmmw .t . . .la...fl......u . . . . )- Hagan? ti! 231.....t: r «Tuareg... .I up .5. #77,. .. .1555.” 35. «um .. .i. .-..7.. . . .v .. . M 33.7. .. ...2 it; .2. . 15.1.... I “7.3 K\ m 9 U‘ Q» 5 w ‘— :5; on This is to certify that the dissertation entitled THE IMPORTANCE OF PHYSICAL EDUCATION CLASSES IN RELATION TO PHYSICAL ACTIVITY BEHAVIORS, PHYSICAL FITNESS, AND ACADEMIC ACHIEVEMENT IN MIDDLE SCHOOL CHILDREN presented by Dawn Podulka Coe has been accepted towards fulfillment of the requirements for the PhD. degree in Kinesiologx a Major Professor’s Signature December 12, 2003 Date MSU is an Al‘fimativo Action/Equal Opportunity Institution PLACE IN RETURN Box to remove this checkout from your record. To AVOID FINES return on or before date due. MAY BE RECALLED with earlier due date if requested. DATE DUE DATE DUE DATE DUE APR222005 .0422 133 6'01 cJCIRClDateDuepss-QIS THE IMPORTANCE OF PHYSICAL EDUCATION CLASSES IN RELATION TO PHYSICAL ACTIVITY BEHAVIORS, PHYSICAL FITNESS, AND ACADEMIC ACHIEVEMENT IN MIDDLE SCHOOL CHILDREN BY Dawn Podulka Coe A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Department of Kinesiology 2003 ABSTRACT THE IMPORTANCE OF PHYSICAL EDUCATION CLASSES IN RELATION TO PHYSICAL ACTIVITY BEHAVIORS, PHYSICAL FITNESS, AND ACADEMIC ACHIEVEMENT IN MIDDLE SCHOOL CHILDREN BY Dawn Podulka Coe The purpose of this study was to determine whether participation in physical education class alters daily physical activity behaviors, health-related fitness, and academic performance. This dissertation contains three sets of research questions. The first set of research questions dealt with the effect of physical education class on physical activity behaviors. The study design allowed for the determination of differences in physical activity (in 30 minute time blocks) as a function of semester of physical education enrollment, test time, and an interaction between the two. There was no effect of physical education enrollment on physical activity. However, there was an effect of test time on physical activity levels. Participants were most active at the beginning of the school year. Activity levels dropped Significantly at the study midpoint and then rose again at the end of the school year. The results infer that there is a seasonality effect on the students’ out of class physical activity behavior. The second set of research questions dealt with the effect of physical education class on health-related fitness, and most specifically, cardiorespiratory endurance. The study design allowed for the determination of differences in cardiorespiratory endurance (PACER shuttle run laps) as a function of semester of physical education enrollment, test time, and the interaction between the two. There was no effect of physical education class enrollment on cardiorespiratory endurance. There was a significant effect of test time on cardiorespiratory endurance. Students achieved the highest number of lapS at the beginning of the school year, regardless of physical education class enrollment. There was also a Significant interaction between semester of enrollment and test time. The interaction was illustrated by the fact that students who were enrolled in physical education class during the first semester had the highest initial fitness levels. The final set of research questions dealt with the effect of physical education class on academic achievement. The research design allowed for the determination of differences in academic achievement as a function of semester of enrollment and physical activity. There was no effect of physical education enrollment on academic achievement, detemiined by grades and standardized test scores. Students who achieved Healthy People 2010 recommendations for vigorous physical activity achieved higher grades compared to other students; this relationship was not found with standardized test scores. Moderate physical activity did not affect grades or standardized test scores. In conclusion, results from this study indicate no Significant relationship between physical education class enrollment, cardiorespiratory endurance, and academic achievement. However, vigorous physical activity was significantly related to higher academic achievement. These results may provide an impetus to improve physical education programs in order to increase both moderate and vigorous physical activity levels during class. ACKNOWLEDGEMENTS First and foremost, I would like to thank my advisor, Jim Pivamik. I could not have asked for a better mentor. It has been a pleasure to work with you for the past four years. You have taught me a great deal and I will forever be grateful to you. You have prepared me well for my academic career and I can only hope to achieve a fraction of what you have. I hope someday that I can have the same impact on my students that you had on me. Dr. Chris Womack and I came to MSU the same year, so I have always felt a special bond with him. Chris, I enjoyed our runs together, especially when I could keep up! I have learned a great deal from you both in class and in the research lab. Dr. Bob Malina, you have taught me the importance of growth and maturation. By working with you, I have learned to be critical of the literature and not to take it at face value. Dr. Mat Reeves, you have led me to think critically (especially about statistics!) and have helped to bring out the epidemiologist in me. I truly appreciate all the time and effort all of my committee members have dedicated to me and this enormous project. My mother and father, Rich and Lenora Podulka are the greatest parents that anyone can ask for. Although I left home almost ten years ago, they have continued to support me from afar. They have always pushed me to do that best that I can. I hope I make them as proud of me as I am of them. My brother and Sister, Richie and Desi, tried to get out of school as quickly as I could, while I never wanted to leave. Although we don’t see each other very often, we have a Special bond and they truly are my best friends. I would like to thank my iv husband Matt for the support and patience he has shown me, especially over the past 2 years. He was always there to let me know that things would be ok and has always helped me keep my focus. I could have asked for a better partner for life. I would like to acknowledge Taryn VanRhee, my research assistant, who literally worked for pennies an hour to help me finish my dissertation. Without her help, this project would not have been possible to the extent that it was. I want to thank Evie Warner and Craig Poppema for volunteering their time to help with data collection. I want to thank the HERLerS for making my time at Michigan State on of the greatest times in my life. You are all truly awesome people to work with and I already miss you! Jo Ann JaneS, thank you for being a friend, supplying me with candy, and always knowing how to fix my mistakes, you are the greatest! I would also like to acknowledge the following people, departments and organizations: 0 Linda Pivamik. the lovely bride of my advisor. Thank you for your kindness and support throughout my career at MSU. o The West Ottawa public school district administrators Jerry Klomparens and Rich Zuker. . The West Ottawa Physical Wellness teachers for allowing me to steal students out of their classes virtually every day. 0 The Department of Kinesiology for the support that l have received throughout graduate school. . The College of Education for also supporting me through the Dissertation Completion Fellowship. 0 The North American Pediatric Exercise Society and Blue Cross/Blue Shield Foundation of Michigan for monetary support. TABLE OF CONTENTS LIST OF TABLES ............................................................................................... viii LIST OF FIGURES ............................................................................................. ix CHAPTER 1 INTRODUCTION ............................................................................ 1 CHAPTER 2 REVIEW OF LITERATURE ............................................................ 6 Introduction ............................................................................................... 6 Physical Activity ........................................................................................ 6 Physical Activity Assessment .................................................................... 7 Physical Activity Recall ............................................................................. 7 Accelerometry ........................................................................................... 9 Tracking of Physical Activity .................................................................... 10 Physical Inactivity/Sedentary Behaviors .................................................. 11 Physical Activity and Maturity Status ....................................................... 14 Seasonality and Physical Activity Levels ................................................. 16 Physical Education and Physical Activity Levels ..................................... 18 Effect of Physical Activity on Physical Fitness ......................................... 22 Effect of Physical Activity on Academic Achievement .............................. 25 CHAPTER 3 METHODS ..................................................................................... 30 Study Participants .................................................................................... 3O Anthropornetry .......................................................................................... 31 Maturity Status Assessment ..................................................................... 32 FITNESSGRAM Protocol ......................................................................... 33 Body Composition .................................................................................... 33 Cardiorespiratory Endurance ................................................................... 34 Muscular Strength and Endurance ........................................................... 34 Flexibility .................................................................................................. 35 Physical Activity Recall ............................................................................ 35 System for Observing Fitness Instruction Time (SOF IT) ......................... 37 Academic Achievement ............................................................................ 38 Statistical Analyses .................................................................................. 38 CHAPTER 4 RESULTS ...................................................................................... 41 CHAPTER 5 DISCUSSION ................................................................................. 52 APPENDIX A LETTERS OF PERMISSION ........................................................ 66 APPENDIX B HUMAN SUBJECTS APPROVAL ................................................. 69 vi APPENDIX C CONSENT FORM ........................................................................ 71 APPENDIX D THREE-DAY PHYSICAL ACTIVITY RECALL .............................. 74 APPENDIX E SUPPLEMENTAL QUESTIONNAIRE ........................................... 80 APPENDIX F SYSTEM FOR OBSERVING FITNESS INSTRUCTION TIME (SOFIT) ......................................................................................... 82 APPENDIX G ANOVA SOURCE TABLES FOR TABLE 2 .................................. 84 APPENDIX H ANOVA SOURCE TABLES FOR TABLE 3 .................................. 86 APPENDIX I ANOVA SOURCE TABLES FOR TABLES 4 AND 5 ...................... 88 APPENDIX J PERCENT OF STUDENT IN THE HEALTHY FITNESS ZONE FOR FITNESSGRAM TESTS ....................................................... 90 REFERENCES ................................................................................................... 92 vii Table 1. Table 2. Table 3. Table 4. Table 5. Table 6. Table 7. Table 8. LIST OF TABLES Subject age, anthropometric, and demographic data .......................... 42 Pretest, midpoint, and posttest activity/sedentary variables ................ 44 Pretest, midpoint, and posttest health-related fitness variables .......... 46 Midpoint and posttest academic achievement variables ..................... 48 Distribution of grades, moderate, and vigorous activity physical activity scores .................................................................................................. 49 Activity levels during physical education classes using SOF IT (% of class time) by semester ...................................................................... 5O Lesson Context Decisions during physical education classes using SOFIT (% of Class time) ....................................................................... 50 Teacher Involvement Decisions during physical education classes using SOF IT (% of class time) ....................................................................... 5O viii LIST OF FIGURES Figure 1. Tirneline for data collection ................................................................ 31 CHAPTER 1 INTRODUCTION In adults, physical activity has a protective effect against morbidity and mortality from many chronic diseases. For example, physically active persons and those with high cardiorespiratory fitness have a lower overall mortality rate than sedentary individuals and those with low cardiorespiratory fitness, respectively 5. Low levels of physical activity or cardiorespiratory fitness increase the risk of cardiovascular disease mortality, which is the number one cause of death in US.69 In contrast, physically active persons may have a reduced cardiovascular disease (CVD) risk 43. In children, the presence of CVD risk factors may indicate the future development of disease, which manifests much later in life. Risk factors that track into adulthood include dyslipidemia, hypertension, obesity, impaired glucose tolerance, and sedentary behavior 11:69:70. Each of these risk factors can be modified positively through physical activity. Therefore, it is important that children become physically active during childhood and continue this behavior through adolescence into adulthood, so that their risk of CVD and all cause mortality is reduced. High levels of physical activity also positively affect health-related fitness levels. Rowlands et al. and SimonS-Morton et al. found that increased levels of physical activity resulted in increased test time in the Bruce treadmill test and increased distance in the mile run/walk test, both suggesting improvements in cardiorespiratory fitness 50.53. Sallis et al. found that increased physical activity levels were associated with all five components of health-related fitness (body composition, cardiorespiratory endurance, muscular strength, muscular endurance, and fiexibility)53. In addition to the effects physical activity has on CVD risk factors and health-related fitness, it may also affect academic achievement. Shephard et al. found that children assigned to a daily physical education Class earned significantly better grades than children who were assigned to an extra academic course57. Using data from the Youth Risk Behavior Surveillance System (Y RBSS) survey, Pate et al. concluded that youth with low physical activity participation levels perceived their academic performance to be low45. Evidence of physical education Class participation being positively related to academic performance could help administrators convince school boards of the need for year-long, required physical education programs. According to data obtained from the YRBSS survey, approximately 73% of Michigan's high school students (grades 9-12) do not participate in moderate physical activity, defined as activities that make them sweat or breathe hard for 330 minutes on 35 of the past 7 days. Also, 35% of Michigan’s high school students do not participate in vigorous physical activity, defined as activities that make them sweat and breathe hard for 320 minutes on 33 of the past 7 days“. Low levels of physical activity in many Michigan youth exemplify a trend towards sedentary lifestyles. Youth are adopting habits that contribute to the evolving pediatric obesity epidemic as well as the development of other cardiovascular risk factors such aS high cholesterol and blood pressure”. Daily physical education class is one way that youth can achieve physical activity levels that correspond with the Surgeon General’s recommendation of 30 minutes of moderate physical activity performed most days of the week 59. However, only 34.5% of Michigan’s high school students are enrolled in physical education classes 11. This number is lower than the national percentage of 56.5%. The percentage of students enrolled in physical education drops as they progress through school. In grade 9, 78.9% of students were enrolled in physical education, 60.9% in grade 10, 40.7% in grade 11, and 36.6% in grade 12. Also, only 26.9% of Michigan students enrolled in physical education attend class daily. At the national level, daily participation in physical education is 29.1%. These percentages also decline as students progress through high school (grade 9 (42.1%), grade 10 (30.4%), grade 11 (20.0%), and grade 12 (20.1%) 11. These physical education participation findings are particularly ominous because youth who do not have regular physical education classes may not make up the activity that they would have done in class, outside of school 14. Thus, physical education classes may provide the only physical activity performed by youth during the day. In addition to providing daily physical activity, physical education classes may aid in the development of an active lifestyle 21. Students from the West Ottawa, Michigan school district have a daily physical education requirement for one half of the school year and an arts and computers class for the remaining half of the school year. Thus, approximately half the students are randomly assigned physical education class the first semester (arts and computers the second semester) and the remaining students have arts and computers the first semester (physical education the second semester). This model provides an excellent opportunity to study the effects of daily physical education class. The overall purpose of this study was to determine whether participation in a physical education class alters daily physical activity behaviors, health related fitness scores, and academic performance. This dissertation includes nine research questions and hypotheses: Research Question 1: Is there an effect of semester (first or second) on students' physical activity behavior outside of school? Research Question 2: Is there an effect of physical education class enrollment (yes or no) on students’ physical activity behavior outside of school? Research Question 3: IS there an interaction between semester (first or second) and physical education class enrollment (yes or no) on students’ physical activity behavior outside of school? Hypothesis: Students enrolled in physical education class will be more active outside of school compared to those not enrolled in physical education class. Students enrolled in physical education during the first semester (late summer and fall) will be more active outside of school than those enrolled in physical education class during the second semester (winter and spring). Research Question 4: Is there an effect of semester (first or second) on students’ health-related fitness? Research Question 5: Is there an effect of physical education class enrollment (yes or no) on students’ health-related fitness? Research Question 6: Is there an interaction between semester (first or second) and physical education class enrollment (yes or no) on students' health- related fitness? Hypothesis: Students enrolled in physical education class will have higher levels of health-related fitness than those not enrolled in physical education class. Students who have physical education the first semester will have higher levels of health-related fitness than those enrolled in physical education class the second semester. These higher levels of health-related fitness will be due to the hypothesized increase in activity levels during the first semester. Research Question 7: Is there an effect of physical education enrollment (yes or no) on students’ academic achievement? Research Question 8: Is there an effect of physical activity level (no activity, some activity, activity meeting Healthy People 2010 guidelines) on students’ academic achievement? Hypothesis: Students enrolled in physical education class will have greater academic achievement than those not enrolled in physical education class. Students who meet or exceed Healthy People 2010 guidelines for physical activity will have the highest academic achievement. CHAPTER 2 REVIEW OF LITERATURE INTRODUCTION Physical activity levels are influenced by many factors that include, but are not limited to age, gender, ethnicity, and maturity status. These factors are not modifiable but may have a profound effect on physical activity levels in youth. Physical activity has been Shown to have a positive influence on physical fitness levels and academic achievement. Enrollment in physical education Classes and season may also play a significant role in youth physical activity levels 19-41 and may influence the tracking of adolescent physical activity during progression into adulthood 24.32. The focus of this literature review is to examine the effects of physical education class status/enrollment, maturity status, and seasonality on physical activity levels and to demonstrate the effect that physical activity has on physical fitness and academic achievement in youth. PHYSICAL ACTIVITY Physical activity is defined as “any bodily movement produced by skeletal muscle that results in caloric expenditure 9.” The term “physical activity” differs from the term “exercise” in that exercise is a subset of physical activity that is “planned, structured, and repetitive bodily movement done to improve or maintain one or more components of physical fitness.” Physical fitness is often a result of a physically active lifestyle. Physical fitness is a set of attributes that people have or achieve that relate to the ability to perform physical activity 9. Physical activity guidelines developed by The Centers for Disease Control and Prevention (CDC) and the American College of Sports Medicine (ACSM) recommend that adults should accumulate at least 30 minutes of moderate physical activity on most, preferably all days of the week 54. Similar physical activity guidelines for children and adolescents have been published as part of the Healthy People 2010 program. Recommendations for moderate activity are 30 minutes per day for at least five days per week. Recommendations for vigorous activity are 20 minutes per day for at least three days per week. Physical Activity Assessment Habitual physical activity is a difficult variable to measure. There are many different methods used to assess physical activity, each emphasizing different activity constructs. Measurement of energy expenditure via indirect calorimetry may provide the best measurement of physical activity. This method also allows determination of activity intensity level. However, in large population studies this method is not feasible. More reasonable physical activity measurement methods include physical activity recall via self-report questionnaires and motion detection monitors (accelerometers). Physical Activity Recall Self-report questionnaires allow an individual to recall how physically active slhe was on the preceding day(s). Questionnaires usually do not incur high costs and generally take a short period of time to complete 8. However, one must be cautious when using questionnaires with young children. Prepubescent youth often cannot recall detailed information as well as adolescents and adults due to their less developed cognitive abilities. Children also tend to lose concentration rather quickly, which may alter results 51. For this reason, it is suggested that subjects filling out physical activity questionnaires be at least ten years old 3. The previous day physical activity recall (PDPAR) is a popular instrument that was developed by Weston et al. 72 The PDPAR requires children to recall what activities they perfonned on the previous day. In addition to activity performed, children also recall the amount of time spent doing the activity, as well as the intensity level of the activity. Physical activity levels are quantified as 30-minute time blocks of moderate and vigorous activity. Days of recall can range from one day to one year 7. One day of recall may not be representative of a child’s habitual physical activity and it may be hard for a child to recall what they did in the previous year. Therefore, it is necessary to collect more than a single day’s worth of data. Multiple days are needed in order to account for intra-individual variability in activity patterns 71. A revision of the PDPAR consists of recalling activities performed over three consecutive days (3DPAR). The child is asked to recall on Wednesday what slhe did on Sunday, Monday, and Tuesday. These three days allow for physical activity information to be obtained on one weekend day and two weekdays. The PDPAR has been validated in children using accelerometry and heart rate monitoring as criterion measures. Weston et al. found a moderate to high correlation between the PDPAR (SO-minute time blocks of moderate and vigorous activity) and heart rate (r=0.53) and PDPAR and accelerometry (r=0.88) 72. The 3DPAR was recently validated by Pate et al. 43, using accelerometry as the criterion method. Self-report of physical activity was converted to total METS, 30-minute blocks of moderate activity, and 30-minute blocks of vigorous activity. These values correlated significantly with comparable accelerometry variables (r=0.27-0.46; P<0.05) using three days of data collection. Accelerometry Accelerometry has become one of the most widely used methods of assessing physical activity in large population studies 66. Accelerometry has also been used as a criterion measure to validate other types of physical activity assessment, such as a physical activity recall 72. The Computer Science and Applications, Inc. accelerometer (CSA) (now known as the Manufacturing Technology, Inc. Actigraph) is a motion-sensitive device that is used to quantify physical activity 2325.31.66.67. The CSA is unobtrusive and comfortable for Children to wear. The CSA has no external buttons, so there is minimal chance of data loss due to subject tampering. The CSA is able to record data for several days, and can be programmed to begin and end data collection at specific times. Stored data can be downloaded easily via a personal computer (PC). The CSA has been validated as a physical activity monitor in laboratory settings, using standard activities such as treadmill walking or running at specific Speeds and grades. The criterion measure used to validate the CSA in laboratory studies has typically been indirect calorimetry (r=0.77-0.94) 1337-4258. The CSA has also been validated in the field by heart rate telemetry, which has been shown to be reliable and valid when used with children 16. Using heart rate telemetry as the criterion measure, studies have shown the CSA to be moderately to highly valid instrument (r=0.50-0.74) for physical activity measurement. The CSA is also sensitive enough to detect intensity changes of normal daily activity performed by children1223v25. In a recent study, Trost et al. 35 suggested that a seven-day monitoring protocol is necessary to assess habitual activity in children when using the CSA accelerometer. By assessing seven days of activity, intraindividual variability as well as differences between weekend and weekday activity may be determined 65. These seven days also allow for lapses in data collection when children forget to replace the activity monitor after removing it for showering, bathing, sleeping, etc. Through the use of a combination of physical activity assessment methods, the 3DPAR and accelerometry, children’s overall habitual physical activity levels may be determined. Tracking of Physical Activity Tracking refers to the maintenance of relative rank within an age-sex group so that a measurement over time tends to follow a pattern where initial measurements predict later levels or relative rank in the same individual 32. Several studies have investigated the relationship between physical activity levels during childhood and those during adulthood. Malina published a review article of studies that evaluated physical activity levels over a lifespan. Overall, there was a moderate correlation (I-—-0.2-0.3) between activity levels during childhood and adulthood 32. Janz et al. found a Similar trend in the Muscatine study, which is a longitudinal, population-based investigation of cardiovascular 10 disease risk factors in youth 24. Physical activity was assessed once every three months over five consecutive years. The authors found that physical activity levels during childhood Show a moderate correlation (#032065) to activity levels in adolescence. Telama et al. found that children, whose primary source of physical activity was sports participation, had an increased probability of higher physical activity levels later in life 53. The authors also found a low to moderate correlation (range, r= 0.0-0.27) between physical activity indices over a 12-year period 63. These findings provide evidence that children who adopt a physically active lifestyle may have a better Chance of continuing this behavior later in life. Physical lnactivltylSedentary Behaviors Research Shows that the average child is sufficiently active to meet recommended adult guidelines for physical activity, which have been defined as 20 to 30 minutes per day of moderate to vigorous conditioning activities 52. Sallis reviewed several studies that evaluated habitual activity levels in youth 52. Overall, in studies conducted with children, both boys and girls met the recommended levels for physical activity. However, the picture is very different when children enter adolescence, particularly for girls. Once girls reach mid to late adolescence, they no longer perform adequate amounts of activity to meet guideline recommendations 52. Suggested reasons for this decline include barriers to organized sport activities, social pressure, and the girls’ lack of perceived competence in their abilities to perform physical activities. 11 Some research has shown that very few children are completely sedentary. Krisjansdottir & VIlhjalmsson 29 evaluated 3,270 11-16 year-old Icelandic school children and adolescents. Physical activityfInactivity levels were assessed through use of a questionnaire. The authors found that only 1% of the students in their study were “all day sedentary.” During leisure time, the percentage of students who were sedentary rose to 31 .3%, meaning that the majority of study participants were active only during the school day in physical education class 29. Myers et al. 41 suggests that a partial explanation for decreases in physical activity levels of Bogalusa Heart Study participants may be the fact that children who participate in sedentary activities must reduce or discontinue their participation in physical activities due to time constraints from the sedentary activities. The investigators studied physical and sedentary activity in 995 children in grades 5-8. Physical activity levels and sedentary behaviors were assessed using the Self-Administered Physical Activity Checklist, a 24-hour recall instrument. It is significant that Myers et al. also found that children do not compensate for a lack of activity during school by increasing activity at other times 41. Dale et al. found results similar to those of Myers et al. in a study that restricted physical education Classes and recess time 14. Participants were 76 3m and 4th grade children. During the study, two days were categorized as active when children participated in physical education class and outdoor recess. There were also two days categorized as restricted. During restricted days the 12 children did not have physical education class and recess was spent indoors at a computer terminal. Dale et al. found that children did not compensate for a sedentary school day by increasing levels of physical activity outside of school. In addition, this study showed that when the children were active during the school day they were more active after school compared with to when their activity was restricted during the school day. Physical activity levels were assessed using accelerometry. Gordon-Larsen et al. 19 also found that when children participated in a daily physical education program, they were more than twice as likely to participate in moderate to vigorous physical activity outside of school. Data from this study came from a nationally representative sample from the 1996 National Longitudinal Study of Adolescent Health. Participants were 17,766 US. adolescents enrolled in US. middle and high schools 19. Studies discussed in the previous few paragraphs provide evidence that if children are physically active during the school day that they will be more likely to continue this behavior outside of school. However, this is not always the case. Some children may only have the opportunity for activity in school. If this opportunity is not available, the children may become sedentary. Current statistics Show that the percentage of students enrolled in physical education classes is declining. As students progress in school, 2001 Youth Risk Behavior Surveillance System (YRBSS) data Shows that enrollment in physical education classes declines from over 74% in ninth grade students to only 31% in twelfth grade students 20. Over the past decade, data show that participation in 13 daily physical education classes is also declining. In 1991, 42% of high school students participated in daily physical education classes 59. In 2001, the percentage of students attending physical education classes was reduced to 29% 2°. The current decline in physical education class enrollment and daily physical education participation may play a role in the decreased amount of moderate and vigorous physical activity performed by youth. Physical Activity and Maturity Status Transition through puberty may affect youth physical activity levels. This may be due to physical changes such as an increase in deposition of body fat, which tends to have a negative influence on motor performance. Conversely, physical activity levels may also affect when a child begins to mature and the rate of maturation. Numerous studies have been published that examine both of these relationships. Kemper et al. 23 examined the influence of maturation (from age 12-22) on physical activity patterns in 200 youth participating in the Amsterdam Growth and Health Longitudinal Study. Biological maturation was assessed using a hand- wrist x-ray to determine skeletal age; these assessments were completed four times over the course of the study. For the purpose of statistical analyses, the youth were categorized as early, late, and average maturers. Physical activity levels were estimated using a structured interview to determine average weekly time spent performing physical activity. Results showed a trend of late maturers. both male and female, being slightly more active than early maturers. This trend was only significant (P<0.05) for males in the young adult period ( 17-22 years). 14 Results from this study Should be interpreted with caution because skeletal age cutpoints were three months past (late maturer classification) or prior to (early maturer classification) calendar age. Three months is standard estimate error for skeletal maturity, therefore some subjects may have been misclassified. Bradley et al. 5 studied the effect of maturity status on physical activity. This study was part of the Cardiovascular Health in Children and Youth study. Subjects (n=656) were drawn from 63 elementary, middle, and high schools in North Carolina and were assessed once a year for six years, starting with 3'‘1 and 4‘" grades. Physical activity levels were determined through the use of an activity questionnaire. Pubertal status was determined using the Pubertal Development Scale in sixth grade continuing through tenth grade. Results showed that for middle school girls, early maturation was a predictor for increased sedentary activities (P<0.0001). Pubertal status was not a predictor of activity in high school girls, middle school boys, or high school boys. After analyzing data from previous studies, Malina and Bouchard 3 determined that regular activity does not accelerate nor delay somatic or skeletal maturation. A relationship between activity and sexual maturation could not be determined due to unavailability of information on the subjects. In a longitudinal study that compared inactive and active children, Malina 31 concluded that regular physical activity and sport training appear to have no effect on timing of peak height velocity, rate of growth in stature or attained stature. Beunen et al. 4 also examined the effect of physical activity on maturation as part of the Leuven Growth Study of Belgian Boys. This longitudinal study 15 followed 588 boys for five years, from ages 13-18 years. From the subject pool, 64 boys (32 active, 32 inactive) with complete longitudinal data were selected. Activity status was determined using a sport participation questionnaire. Skeletal maturation was determined using hand-wrist x-rays and peak height velocity was estimated using nonsrnoothed polynomials. Results showed that indicators of somatic and skeletal maturity did not differ between the active and inactive groups. These results suggest that activity status does not influence biological maturation (timing of peak height velocity or skeletal maturation). Overall, previous studies Show a trend of increased levels of physical activity related to late maturation and increased sedentary activities related to early maturation. It also appears that physical activity does not have a detrimental effect on growth and maturation. Although children may exercise without the risk of interruption in the growth and maturation process, researchers should account for maturity status when studying physical activity in children since it may influence activity level. Seasonality and Physical Activity Levels Season may affect physical activity levels due to temperature differences, precipitation, and amount of daylight. Extreme hot and cold temperatures and inclement weather limits the participation of youth in outside activity. If alternatives to outside activity are not readily available, youth may perform more sedentary activities such as television watching and surfing the lntemet. Baranowski et al. 3 studied the effect of season on physical activity in 3- and 4-year-old Children as part of a longitudinal study in Galveston, TX. Data on 16 physical activity were collected on 191 children using direct observation [Children’s Activity Rating Scale (CARS)] for up to four days per year for three consecutive years. Outside activity was lower for all children during the summer months, particularly in July, which is the hottest month in Galveston. During January through July, physical activity levels decreased in all children and inside activity levels were higher during the months of August through November. These findings suggest a negative effect of extremely hot/humid conditions on the activity levels of Children. Crocker et al. 13 also investigated the seasonal effect on physical activity in youth using the Physical Activity Questionnaire for Older Children (PAC-Q). The subjects (n=200; age 8-16 years) in this study were participating in the Saskatchewan Paediatric Bone study. During a one-year period, the PAC-Q was administered three times to each student. The PAC-Q is a 7-day recall instrument. PAC-Q scores were determined using an average of nine physical activity items, these scores ranged from one to five. The physical activity scores from the PAC-Q were collected in January, April, and October-November. There was no measurement taken during the summer months. Results revealed that physical activity scores in April (3.10) were significantly higher than those in January (2.84) and October-November (2.79). The authors speculated that this may be due to warmer temperatures and longer daylight hours in April compared with the other months. Findings from the National Children and Youth Fitness Study I also Show a seasonal effect on youth activity levels outside of school. Ross et al. 49 found 17 that activity levels were highest in the summer. These values were 42% higher than the annual average of 760 minutes/week. Physical activity levels were lowest in the winter (69% of the annual average). During the fall, activa levels dropped below summer levels (84% of the annual average), and in the spring activity levels reached the annual average. Activity levels were determined by self-report on a one-year physical activity recall. These seasonal differences in physical activity may play a significant role in Michigan children’s habitual physical activity levels. Pivamik et al. examined seasonal variation in leisure-time physical activity in 2,843 Michigan adults using the 1996 Michigan Behavioral Risk Factor Survey 47. Results from this study indicate that the average weekly leisure-time energy expenditure in Michigan adults was significantly greater (P<0.05) during the spring (April - June) and summer (July — September) than during the fall (October — December) and winter (January - March). 47 It may be likely that Michigan children may follow the same pattern of physical activity as Michigan adults. Due to the fact that Michigan experiences the extremes of all four seasons (i.e., hot summers, cold winters), the potential for a seasonal effect should be considered. In the case of the present study, controlling for a seasonal effect was done through the assessment of physical activity by either recall or accelerometry at various times during the year. Physical Education and Physical Activity Levels Daily physical education class is one way that children can achieve levels of physical activity that correspond with the Surgeon General’s recommendation 18 of 30 minutes of moderate physical activity perfomied most days of the week 69. However, data from the 2001 YRBSS survey indicate that the percentage of high school students who are enrolled in physical education classes is 44% and the percentage of students that participate in daily physical education is only 32% 20. Participation in physical education classes tends to decline through middle school and high school 39. Simons-Morton et al. 59 studied the physical activity levels of fifth-grade students during physical education Classes. Physical activity was assessed using direct observation. Overall, 157 students in twenty elementary schools were observed. Results Show that on average, 8.6% of physical education class time was Spent in moderate to vigorous activity and 68.1% of class time was sedentary 59. No school in the study met the recommendation that 50% of class time be spent in moderate to vigorous activities (Healthy People 2010 Guidelines). The authors suggest that daily physical education will not increase children’s overall activity levels unless a greater proportion of Class time is spent on activities. In a subsequent investigation, Simons-Morton et al. 60 studied elementary and middle school children using a revised version of their original observational instrument. Twenty elementary schools and seven middle schools were sampled. For comparison purposes, the authors selected an additional nine elementary schools and six middle schools, identified as having excellent physical education programs. Results from this study were similar to their previous study, as average moderate to vigorous physical activity in the 19 elementary schools only accounted for 8.6% of the time spent in physical education class. This number was significantly less (P<0.05) than the middle school (16.1%) and the comparison elementary (20.6%) and middle schools (24.0%) considered having high quality physical education programs. Moreover, the results showed that no school met the recommended 50% minimum of moderate to vigorous physical activity per Class (Healthy People 2010) or the estimated national average of 27%. McKenzie and colleagues 34 also examined activity levels in physical education classes. In one study, this group looked at third-grade classes in 95 elementary schools in four states. The System for Observing Fitness Instruction Time (SOF IT) was used to observe these classes. This system differs from the instrument used by Simons-Morton et al. because it assesses not only student activity level, but also lesson context and teacher behavior. Results from this study showed that children engaged in moderate to vigorous physical activity for an average of 37% of a given class period. This provides only a small percentage (12% of moderate to vigorous physical activity and 25% of vigorous physical activity) of nationally recommended physical activity levels. McKenzie and colleagues 35 also looked at physical activity levels in adolescents attending 24 middle schools in southern California. SOF IT was used to assess children's activity levels, teacher behavior, and lesson context. Four students were randomly selected during each observation period and monitored to determine activity levels. During this study, 430 lessons were observed. An average of 48.5% of lesson time (16.5 minutes) was spent with the 20 children participating in moderate to vigorous physical activity. Only 14.6% of lesson time was spent participating in activity at an intensity level to improve cardiovascular fitness. Overall, only 83 minutes of moderate to vigorous physical activity was accumulated over the course of the week, a value that is lower than recommended physical activity levels for children. Overall, these studies show that participation in physical education class does not contribute significantly to overall time spent by the children performing moderate and/or vigorous physical activity levels. Gordon-Larsen et al. 19 investigated the determinants of physical activity and inactivity patterns in youth who participated in the 1996 National Longitudinal Study of Adolescent Health. Results derived from this data set indicate increased levels of physical inactivity and decreased levels of moderate to vigorous physical activity are associated with a decrease in physical education participation. Also, students who participated in physical education classes were more than twice as likely to engage in increased levels of moderate to vigorous physical activity outside of scth (AOR=2.21; 95%Cl=1.82-2.86). Taken together, these studies clearly illustrate the need to implement quality physical education programs in schools. It appears that physical activity levels outside of school are influenced by the amount of activity perfon'ned during physical education classes. Physical education class may be the sole source of physical activity in some children. Therefore, it is necessary to increase physical education class enrollment rates, rates of participation in daily physical education, and the amount of time spent doing moderate-vigorous activity during 21 class. These changes may help children become more active as well as aid in their development of a healthy, active lifestyle. Effect of Physical Activity on Physical Fitness The literature concerning the relationship of physical activity to physical fitness in youth indicates a weak to moderate relationship. In the majority of studies, physical fitness has been represented solely by cardiorespiratory fitness, which has been Shown to predict cardiovascular disease (in adults) as well as other chronic disease risk. A small number of studies have looked at overall health-related fitness, which includes cardiorespiratory endurance, body composition, flexibility (low back/hamstring), and muscular strength and endurance (abdominal and upper body). Morrow and Freedson 40 published a review article to determine whether a consensus could be reached concerning the relationship between physical activity and aerobic fitness. Overall, they included 37 studies in their analysis. Review of studies was limited to those that included physical activity assessment (assessments included self-report, heart rate monitor, and/or motion sensor devices), a direct measure of VOW or VOW, or a field test of aerobic capacity. There were no age limitations due to limited number of studies on adolescents. Correlations were derived from works relating physical activity to aerobic fitness. The authors concluded that overall, there is a small to moderate relationship between physical activity and aerobic fitness in youth (r~0.16). However, the authors noted that some studies did not Show a relationship between the two variables. 22 Pate et al. 44 examined the relationship between physical activity and physical fitness in a sample of third and fourth grade students (1150 boys, 1202 girls) who were part of the National Children and Youth Fitness Study (NCFYS). In this cross-sectional study, physical activity was assessed using two questionnaires, one completed by the parents/guardians and one completed by the teacher. Physical fitness (cardiorespiratory endurance) was assessed using the 1.6km walk/run test. Results showed a moderate relationship beMen numerous physical activity variables and physical fitness (r=0.42-0.46; P_<_0.05). Rowlands et al. 50 evaluated the relationship between activity levels and aerobic fitness in 8- to 10-year-old children. Thirty-four children (17 boys, 17 girls) from two primary schools in North Wales participated in the study. Physical activity was estimated using heart rate telemetry, a pedometer, and the Tritrac- R3D activity monitor. The children wore the pedometer and the Tritrac for an average of 4.93 days each and the heart rate monitor was worn for 1 day. Aerobic fitness was assessed using the endurance time attained during the Bruce treadmill protocol. Output measures from the pedometer and the Tritrac were positively correlated (Tritrac, r=0.66; pedometer, r=0.59; P<0.01) with fitness for the entire group indicating a relationship between activity and fitness. Katzmarzyk et al. 26 examined health-related physical fitness and physical activity in Canadian youth. This was a cross-sectional sample derived for The Quebec Family Study. There were 640 subjects in this study (age range: 9-18 years). Each subject completed a three-day activity record. Health-related fitness was assessed using the PWC15o (estimate of cardiorespiratory 23 endurance), skinfolds (body composition), sit-ups (muscular endurance), and maximal voluntary isometric contraction of the quadriceps (muscular strength). Results showed a weak to moderate relationship between physical activity and health-related fitness in youth (r=0.19-0.32; P<0.05). Huang and Malina 22 also studied physical activity and health-related fitness in youth. Participants in this study were 282 Taiwanese adolescents 12- 14 years of age. Physical activity was estimated using a three-day physical activity record. Health-related physical fitness was assessed using the one-mile run (cardiorespiratory endurance), sit-ups (abdominal strength and endurance), sit-and-reach (flexibility), and sum of skinfolds (body composition). This study also revealed that health-related fitness is related to physical activity (r=0.23- 0.34). However, the range of the variance in fitness accounted for by estimated physical activity is low (<1-12%). Sallis et al. 53 investigated the relationship between habitual physical activity and health-related fitness. Participants included 528 apparently healthy fourth grade children. Physical activity was assessed using child self-report, parent report, and a one-day accelerometer score. Health-related physical fitness was assessed using the FITNESSGRAM battery of tests, which included the mile run (cardiorespiratory endurance), sit-ups (abdominal strength and endurance), pull-ups (muscular strength and endurance), sit-and-reach test (flexibility), and sum of skinfolds (body composition). Results showed significant correlations (r=0.10-0.24) among all fitness variables and physical activity index, with the exception of skinfolds and number of pull-ups for girls. The researchers 24 concluded that the physical activity index was significantly associated with all five fitness components. The literature indicates a weak to moderate relationship between physical activity and physical fitness in children. Correlations between physical activity and fitness vary greatly among the studies (r=0.10-0.66), with the majority showing a weak relationship between the two variables. In contrast, approximately 2/3 of the variance in aerobic fitness in adults is a function of their physical activity behaviors 69. Since a stronger relationship exists between activity and fitness in adults, it is recommended that youth become active so they may be more likely continue this behavior into adulthood. These stronger relationships in adults may be due to fact that adult are fully matured, whereas children as still growing and maturing. Also many of the fitness tests have been developed on adults and therefore may not be valid measures of fitness on children. Effect of Physical Activity on Academic Achievement Research on the effect of physical activity and academic achievement has provided inconsistent results that overall, do not Show a distinct relationship between the two variables. The research that is available is variable in study design, measurement of physical activity, and measurement of academic achievement. Daley and Ryan 15 studied academic performance and the effect of participation in physical activity in 232 British secondary school Children (ages 13-16 years). Participants” physical activity levels were assessed using a 25 questionnaire, which determined frequency and duration of sport-based physical activity. Academic achievement was measured using English, mathematics and science exam scores. Results revealed no significant correlations between sport-based physical activity and academic achievement. Dwyer et al. 17 evaluated the relationship between academic performance and physical activity in 7,961 Australian children participating in the Australian Schools Fitness and Health Study. Subjects’ ages ranged from 7-15 years. Each student's academic performance was categorized as excellent, above average, average, below average, or poor by a school representative, usually the principal. Sport participation and exercise information was assessed using a questionnaire. Only students who were nine years of age or older completed the questionnaire. A significant, although weak, correlation (r=0.29-0.51; P<0.001) was found between scholastic ability and the two measures of physical activity (sport participation and exercise). This suggests that children who are more active in sports may perform better academically. Tremblay et al. 34 examined physical activity and academic achievement in 12-year-old Canadian children as part of the Elementary School Climate Study. The participants in this cross-sectional study consisted of 6,923 sixth grade students. Physical activity was assessed using a questionnaire, which included four questions on participation in physical activities, both in and outside of school. Academic achievement was assessed using standardized test scores in reading, mathematics, science, and writing. This study revealed that physical activity levels may be inversely related to achievement. An increase in physical 26 activity level resulted in a small, nonsignificant reduction in standardized test scores. In this study, the authors also looked at the relationship between physical activity and self-esteem and found a positive correlation (r=0.20). Tremblay et al. concluded that for some children, physical activity may indirectly enhance academic achievement through an increase in self-esteem. Pate et al. 45 examined the relationship between physical activity and academic performance using data from more than 11,000 students who participated in the 1990 Youth Risk Behavior Survey. Physical activity was estimated from two items on the questionnaire and academic performance was based on a single item that asked for students’ perception of the type of student they considered themselves to be (bottom/little above middle or far above middle/best). For the analysis, a subsample of the population was classified as either low active (n=1641) or high active (n=2652). Students who rated themselves academically as bottom/little above middle were almost twice as likely to be low active (OR 1.73; 95%Cl 1.27-2.36). Shephard and Lavallee conducted the Trois Rivieres experiment in the Province of Quebec 55. This study included 546 primary school students. The authors examined the relationship between physical activity and academic performance. Academic perfonnance was determined using report cards that gave letter ratings of A through F for each subject. These letter ratings were converted to a numerical score (1-6) for statistical analyses. In this study, the subjects were assigned to either an experimental group (1 hour per day of additional physical education taught by a specialist) or a control group. The 27 experimental group had a modified curriculum starting in grade 1 and continuing through grade 6. Academic performance in the control group was greater at the beginning of the study (grade 1). However, in grades 2 through 6, the experimental students achieved significantly (P<0.001) greater overall academic performance compared to control students. Caterino and Polak 10 used a different approach and examined the effect of activity on concentration in elementary school students. The Woodcock- Johnson Test of Concentration 73 was administered to 177 second-, third-, and fourth-grade students. The children were Split into two groups, Classroom Activity and Physical Activity. After each activity, the children completed the concentration test. Results revealed no significant differences in the concentration scores for the two groups in the second- and third-grade children. In the fourth-grade children, the mean concentration score was significantly greater (P<0.05) for the Physical Activity group compared to the Classroom Activity group. The authors concluded that physical activity was not detrimental to students’ performances. In fact, they performed better than those students who did not perform physical activity. The authors also speculated that nonsignificant differences in the second- and third- graders might be due to developmental differences in concentration ability. Overall, previous studies indicate a trend of increased physical activity leading to improved academic achievement. The majority of the studies performed were cross-sectional. This study design provides information relative to one specific time period and is unable to assess changes that may occur over 28 a specified amount of time. Due to a variety of different study designs and methodologies, it is important to conduct further research in this area so that a more defined relationship between activity levels and academic achievement may be determined. Longitudinal studies designed to examine various aspects of academic achievement may provide a clearer picture of this relationship. If a positive relationship can be established through further research, administrators and school boards can be made aware of die significance of physical education class and the role it might play in the academic achievement of their students. This may lead to the reduction in the number of physical education programs being cut as well as the increase in the percentage of students participating in daily physical education class. 29 CHAPTER 3 METHODS Study Participants Participants were 214 students out of approximately 622 in the 6th grade of the West Ottawa School district. Students' ages ranged from 10 - 13 years. Permission to conduct the study was obtained from the schools’ principals and administrators (Appendix A). The West Ottawa public school system is located in Holland, Michigan, whose population is middle to upper-middle class. The racial breakdown of the student population is 62.7% Caucasian, 17.5% Hispanic, 8.6% Asian, 5.8% multiracial, 3% Black, 2.1% Migrant, 0.2% Native American, and 0.1% Pacific Islander. There were 7,875 students children enrolled in these schools (K-12) for - the 2002-2003 academic year. There are nine elementary schools, one 6'h and 7'" grade building, one 8th and 9‘" grade building, and a high school (10“ -12"‘ grade). All study participants attended school in one building. The school year begins during the last week in August and ends mid-June. Outside of school activity opportunities included “Girls on the Run” and specialized extracurricular clubs (i.e., Lego league, magician’s club etc). There are no school sponsored sports teams at the sixth grade level. Students in the school were randomly assigned to one of two groups by school administrators. One group had physical education the first semester (August - mid-January) and one group had physical education the second 30 semester (mid-January — June). During the semester that the children did not have physical education, they were enrolled in arts and computer classes. All classes met each day of the week for 55 minutes. Subjects participated in the study on a volunteer basis. Each subject was assessed three times during the scth year. The first assessment occurred at the beginning of the school year (August — September), the second assessment was taken at the midpoint of the school year (January), and the third assessment was taken at the end of the school year (May - June). Figure 1 gives a timeline of these events. This study was approved by the Michigan State University Committee on Research Involving Human Subjects (Appendix B). Written child assent and parental consent was obtained prior to the subject entering the study (Appendix C). Figure 1. Timeline for Data Collection Semester 1 Semester 2 August- January January - June Pretcst Midpoint Posttest Measurements Measurements Measurements August — September January May - June (Start of semester 1) (End of semester 1, (End of semester 2) Start of semester 2) Anthropometry Each participant’s standing and sitting height was assessed using a moveable anthropometer. Heights were measured (to the nearest mm) by one trained technician. Participants’ weights were assessed (to the nearest 0.1 kg) using a calibrated digital scale (Precision Health Scale UC-300; Milpitas, CA). 31 Height and weight measures were used to calculate each participant’s body mass Index (BMI; kg - m4). Maturity Status Assessment Maturity status of each child was estimated at the beginning, midpoint, and end of this study. Maturity status, determined as the number of years from peak height velocity, was estimated via anthropometric measurements. This method allows maturity status to be estimated in an unobtrusive manner. The following anthropometric measurements were taken; weight, standing height (stature) and sitting height. Sitting height was measured as the distance from a sitting surface to the top of the head with the child seated in a standard position 33. Leg length was estimated using the difference between stature and sitting height. Prediction equations developed by Mirwald et al. 38 were used to determine maturity offset, which is defined as the difference in years between age at peak height velocity and chronological age at the time of the assessment. Children who have not yet reached peak height velocity, have a negative maturity offset prediction value (in years) and children who are at or post their peak height velocity have a positive maturity offset prediction value (in years). The equations are as follows: Equation 1. Prediction equation for boys Maturity offset = -29.769 + 0.0003007 - Leg Length and Sitting Height interaction - 0.01177 - Age and Leg Length interaction + 0.01639 - Age and Sitting Height interaction + 0.445 - Leg by Height ratio 32 Equation 2. Prediction equation for girls Maturity offset = 46.364 + 0.0002309 - leg length and Sitting height interaction + 0.006277 - Age and Sitting height interaction + 0.179 - Leg by height ratio + 0.0009428 - Age and weight interaction Children who have a negative maturity offset prediction were considered pre-peak height velocity and children who have a positive maturity offset prediction were considered post-peak height velocity. FITNESSGRAM Protocol Physical fitness was assessed using The Prudential F ITNESSGRAM Test battery. The FITNESSGRAM is a comprehensive health-related fitness testing system that uses criterion-referenced standards to evaluate fitness performance 43. The five fitness components included body composition, cardiorespiratory endurance, muscular strength, muscular endurance, and flexibility. Brief descriptions of each test follow. Specific instructions for the setup and administration of these tests can be found in the FITNESSGRAM manual 43. Fitness testing was conducted on a subsample of the population (104 students). Cardiorespiratory endurance and body composition were the only components of the FITNESSGRAM that were assessed on all participants. Only data from the PACER test were used in data analysis because cardiorespiratory endurance is the most important measure of health-related fitness. Body Composition Body fatness (% fat) was estimated using calf and triceps skinfold measurements 52. Two trained investigators performed all skinfold 33 measurements (in triplicate) using Lange calipers. In order to reduce the interobserver variability, the two technicians had several practice sessions. Also during pilot testing the technicians assessed skinfolds on approximately 50 subjects to determine their reliability. Results of the pilot testing showed a Chronbach’s Alpha of 0.97 and a Pearson correlation of 0.94. The technical error of measurement was 1.73mm. Cardiorespiratory Endurance The Progressive Aerobic Cardiovascular Endurance Run (PACER), which is a 20-meter shuttle run, was used to determine cardiovascular endurance. A distance of 20 meters was measured on a gymnasium floor, with lines marking the area. Each child ran back and forth to an audible cadence projected from a portable cassette player. The timing was provided by an audiotape with prompts occurring more rapidly as the test progresses. Each 20-meter run counted as one lap. The test ended when the participant was unable to maintain the proper cadence for two consecutive laps. Each child’s score was recorded as the number of laps completed during the test. Prior to testing, the PACER was demonstrated to the children by one of the investigators. Muscular Strength and Endurance The number of push-ups each child could perform was used as an estimate of upper body strength and endurance. A metronome was used to insure that the children performed the push-ups at the proper cadence. The test was stopped when the child’s form needed to be corrected twice. The participant’s score was the number of push-ups completed with the correct form. Abdominal strength and endurance were measured using the curl-up test. A metronome was used so that the child could perform the curl-ups at the proper cadence. The child performed the test until either slhe reached volitional exhaustion or achieved the maximum number of 75 curl-ups. The test was stopped when the child could not keep up with the cadence or broke form. Flexibility Hamstring flexibility was estimated using the back saver sit-and-reach test. The Figure Finder Flex-Tester (Novel Products Inc; Rockton, lL) sit-and- reach box was used to quantify the flexibility score (in inches). Each child performed three trials with the right leg and three with the left leg. The investigator recorded and averaged scores from both legs as an estimate of flexibility. I Physical Activity Recall Each participant's habitual physical activity was estimated using the three- day physical activity recall (3DPAR), a variation of the previous day physical activity recall developed by Weston et al. 72 (Appendix D) Each child was asked about his/her previous day's activities for three consecutive days. The child was asked to recall on Wednesday the activities that were performed on the previous Sunday, Monday, and Tuesday. These three days were divided into 30-minute time blocks. The child was instructed to choose a single activity code for each 30-minute time block. If the child performed more than one activity, the activity performed for the majority of that 30-minute period was listed. A list of activities, 35 with numerical codes, was provided to each child. For each 30-minute time block, the child also provided an intensity level for the activity performed. The intensity levels are described below: Intensity Description Light Require little or no movement with slow breathing Moderate Require some movement; and normal breathing Hard Requires a moderate amount of movement and increased breathiqu Very Hard Require quick movements and hard breathing MET values for each of the activities in the questionnaire are listed in the validation article of the instrument 72 and also in the Compendium of Physical Activity 1-2. For analytical purposes, the number of 30-minute time blocks of moderate and vigorous activity was used to determine each child’s activity level outside of school. In addition to the 30-minute time blocks for moderate and vigorous activity, these activity scores were converted to ordinal data. Scores of 1 (no activity), 2 (some activity), or 3 (activity that meets Healthy People 2010 guidelines) were given to each student, based on his/her activity levels, for both moderate and vigorous activity. Healthy People 2010 guidelines for moderate activity are 30 minutes per day for at least five days per week and for vigorous activity are 20 minutes per day for at least three days per week. A supplemental questionnaire (Appendix E) was given to assess participation in sports and extracurricular activities. 36 System for Observing Fitness Instruction Time (SOFIT) SOFIT is an observation instrument designed to assess variables associated with students’ activity levels and opportunities to become physically fit (Appendix F) 36. SOFIT involves direct observation of the physical education classes while recording student activity levels, curriculum context variables, and teacher behavior. Four randomly selected students in each class, on a rotational basis, were observed every 20 seconds for the duration of the class. There are five activity categories; lying down (1), sitting (2), standing (3), walking (4), and very active (5). Levels of moderate to vigorous physical activity can be determined by combining categories 4 and 5. Phase II of SOFIT is the coding of lesson context. Lesson context was observed every 20 seconds for the duration of the class. Lesson context can be broken down into several categories; management, general knowledge, physical fitness knowledge, fitness, skill practice, and game play. The last phase involves teacher behavior, which is coded as one of the following, promotes fitness, demonstrates fitness, instructs generally, manages, observes, and off-task. Teacher behavior was observed every 20 seconds for the duration of the class. A single observer trained in SOFIT assessed time spent in activity as well as student and teacher behavior during a physical education class. Each physical education teacher was assessed a total of four times, twice during each semester of the school year. The data obtained using SOFIT were used to provide descriptive information regarding the quantity of physical activity performed during physical 37 education class, teacher behavior, and also type of activity generally performed during the class. These analyses were performed subsequent to the statistical analyses to help explain major research findings. Academic Achievement Academic achievement was determined using individual grades for each student in the study from the core classes (English, world studies, science, and mathematics). The individual grades were converted to ordinal data. If the student received a grade of A, the grade was converted to a 5, a grade of B was converted to a 4, a grade of C was converted to a 3, a grade of D was converted to a 2, and a grade of F was converted to a 1. The grades for all core classes were combined for each semester. Therefore, each student had 2 calculated scores, one for each semester. These scores, as well as Terra Nova standardized test scores (administered in April, scores ranged from 1 to 99), were used as measurements of academic achievement. Statistical Analyses The JMP (SAS Institute Inc.) statistical package was used to analyze the data. Statistical power was calculated based on expected differences in physical activity (one 30-minute time block). A power analysis revealed that 142 subjects per group (2 groups) per semester (2 semesters) were necessary to achieve a power of 0.80, at an alpha level of 0.05, assuming an expected difference of one 30-minute time block, and a standard deviation of three 30-minute time blocks. 38 Research Question 1: Is there an effect of semester (first or second) on students’ physical activity behavior outside of school? Research Question 2: Is there an effect of physical education class enrollment (yes or no) on students’ physical activity behavior outside of school? Research Question 3: IS there an interaction beMen semester (first or second) and physical education class enrollment (yes or no) on students’ physical activity behavior outside of school? Analysis: Differences in moderate and vigorous physical activity performed outside of school (30-minute time blocks) were analyzed using a mixed model, repeated measures analysis of variance (ANOVA). This design allowed for the determination of differences in physical activity as a function of a) semester enrolled in physical education (between subjects factor) b) test time (within subjects factor) and c) the interaction between the two. Research Question 4: Is there an effect of semester (first or second) on students’ health-related fitness? Research Question 5: Is there an effect of physical education class enrollment (yes or no) on students’ health-related fitness? Research Question 6: Is there an interaction between semester (first or second) and physical education class enrollment (yes or no) on students’ health- related fitness? Analysis: Differences in cardiorespiratory endurance (PACER laps) were analyzed using a mixed model, repeated measures ANOVA. This design allowed 39 for the determination of differences in cardiorespiratory endurance as a function of a) semester enrolled in physical education (between subjects factor) b) test time (within subjects factor) and c) the interaction between the two. Research Question 7: Is there an effect of physical education enrollment (yes or no) on students’ academic achievement? Research Question 8: Is there an effect of physical activity level (no activity, some activity, activity meeting Healthy People 2010 guidelines) on students’ academic achievement? Analysis: Differences in academic achievement (individual combined scores and Terra Nova scores) were analyzed using a one-way ANOVA. This design allowed for the determination of differences in academic achievement as a function of a) semester enrolled in physical education or b) physical activity level. Both of these variables were between subjects factors. 40 CHAPTER 4 RESULTS Subjects in this study were 214 (34% of total number of sixth graders) sixth grade students randomly assigned (by school administration) to a physical education class either during the first (N=100) or second semester (N=114) of the school year. Subject age, anthropometric, and demographic data can be found in Table 1. 41 Table 1. Subject age, anthropometric, and demographic data (Mean 1 SD, Range) AgelAnthropometrichemographlc Physical Education Physical Education Variables 1" Semester 2"“ Semester n=100 n=114 Age (yrs) 11510.4 11.410.4 10.0-12.8 10.8-12.9 Height (cm) 147.7164 148.3180 1335-1662 1264-1653 Weight (kg) 46.71123 44.21124 28.3-85.6 24.9-95.8 Body Mass Index (BMI) (kg-m") 21.3149 20.0141“ 13.7-34.3 13.1-37.3 Sex Boys 51% 50% Girls 49% 49% Race White 68% 68% Hispanic 14% 10% Black 3% 4% Asian 3% 6% Other 12% 12% Maturity Offset Boys 2010.4 2110.5 ’3-‘1 ‘3-1 Girls 09610.48 01610.63 -2-1 -2-1 In the Race group, “Other" included Hispanic/white, black/white, Asian/white, and Hispanic/black mixes and Native American. *Significant difference at P<0.005 level. Three sets of research questions were developed and investigated over the course of the study. The first set of research questions dealt with the effect of physical education class on physical activity behaviors and included the following three specific questions: 42 Research Question 1: Is there an effect of semester (first or second) on students’ physical activity behavior outside of school? Research Question 2: Is there an effect of physical education class enrollment (yes or no) on students’ physical activity behavior outside of school? Research Question 3: Is there an interaction between semester (first or second) and physical education class enrollment (yes or no) on students’ physical activity behavior outside of school? Data from questions 1-3 are presented in Table 2. ANOVA source tables can be seen in Appendix G. There was no effect of physical education class enrollment on the study participants' physical activity levels. However, there was an effect of time of assessment on the activity levels, regardless of the semester the students were enrolled in physical education class. Midpoint moderate physical activity levels were significantly less than either pretest or posttest values (P<0.0001). In addition, pretest vigorous physical activity was significantly greater than midpoint or posttest values (P<0.0001). 43 Table 2. Pretest, midpoint, and posttest activitylsedentary variables (Mean 1 SD, Range) ActletyISedentary Levels Physical Education Physical Education 1" Semester 2"“ Semester Moderate physical activity (30-mlnute blocks) Pm 8.2 1 2.8 (0-40) 8.1 1 7.3 (0-31) Midpoint 5.9 1 6.7 (0-38)* 5.9 1 7.1 (0-40)* PM 8.8 1 7.6 (0-28) 9.9 1 8.6 (0-28) Vigorous physical activity (so-minute blocks) PM 3.3 1 4.4 (0-20)" 3.2 1 4.4 (0—24)" ""9“” 1.4 1 2.6 (0.11) 1.6 1 4.7 (0-32) Pm 1.6 1 3.3(c21) 2.3 1 4.7 (0-21) FTV time (Minutes) Protest 132.7 1 107.5 (2420) 130.2 1 92.7 (5-360) Midpoint 144.7 1 119.6 (0720) 152.5 1 108.5 (5-480) Posttest 133.6 1 118.6 (0-600) 138.2 1 102.4 (0-420) “Significantly different from pretest and posttest (P<0.0001) *" Significantly different from midpoint and posttest (P<0.0001) Although there was no Significant effect of semester of physical education on activity levels, average values were slightly higher during the semester when the students had physical education class. Specifically, physical activity participation averaged 13% more moderate activity and 32% more vigorous activity in the semester the students were enrolled in physical education class. Television viewing time was not included in the research questions, and thus, was not analyzed statistically. However, mean values were greatest at the midpoint of the study. The second set of research questions dealt with the effect of physical education class on health-related fitness variables and includes the following three specific questions: Research Question 4: Is there an effect of semester (first or second) on students’ health-related fitness? Research Question 5: Is there an effect of physical education class enrollment (yes or no) on students’ health-related fitness? Research Question 6: Is there an interaction between semester (first or second) and physical education class enrollment (yes or no) on students’ health- related fitness? Statistical analyses were run only on cardiorespiratory endurance (PACER laps). Table 3 shows the means, standard deviations, and ranges for all of the health-related fitness variables assessed. The ANOVA source table can be seen in Appendix H. 45 Table 3. Pretest, midpoint, and posttest health-related fitness variables (Mean 1 SD, Range) Health-Related Fitness Variables Physical Education Physical Education 1" Semester 2"“ Semester TPTCER (Laps) (N=100) (N=114) Pretest 23.6 1 13.4 (5-61)* 21.8 1 16.2 (7-58)* Midpoint 21.6 1 12.6 (5-57) 19.5 1 12.3 (4—62) Posttest 19.4 1 9.7 (4-50) 20.4 1 12.9 (4-50) CURL-UPS (number) (N=49) (N=55) Protest 34.8 1 24.2 (1.75) 42.6 1 24.8 (7-75) Midpoint 32.31 24.5 (2-75) 39.8 1 24.8 (3-75) Posttest 41.0 1 25.1 (0-75) 37.2 1 23.8 (0-75) PUSH-UPS (number) (N=49) (N=55) Pretest 9.6 1 6.8 (0-26) 8.8 1 6.5 (0-31) Midpoint 9.1 1 6.3 (0-23) 6.9 1 6.7 (0-25) Posttest 7.3 1 6.7 (0-25) 8.9 1 8.0 (0-25) FLEX-RT (inches) (N=49) (N=55) Protest 11.9 1 2.8 (6-18.5) 11.4 1 2.8(6-17.25) Midpoint 11.8 1 2.7 (525-195) 11.8 1 2.7 (525-195) Posttest 11.8 1 2.7 (525-195) 11.8 1 2.7 (525-195) FLEX-LT (inches) (N=49) (N=55) Pretest 11.8 1 2.7 (4.5-18.25) 11.3 1 3.0 (4.5-17.0) Midpoint 11.5 1 2.7 (525-185) 10.9 1 2.8 (5.0.1675) Posttest 11.5 1 2.4 (6018.0) 11.4 1 2.7 (6.0-18.0) BMI (kg-m7“? (N=110) (N=114) Proton 21.3 1 4.9 (14.9—38.6) 20.0 1 4.1 (13.1-37.3) Midpoint 20.7 1 4.1 (14.3-31.5) 20.4 1 4.2 (13.0-39.1) Posttest 21.2 1 4.5 (137-343) 20.3 1 4.2 (13.3-38.8) *Significantly different from midpoint and posttest (P<0.05) Results revealed no effect of physical education enrollment on cardiorespiratory endurance. There was a significant effect of semester on cardiorespiratory endurance. Regardless of semester of enrollment, students achieved the greatest number of laps during the pretest (P<0.05). There was also a significant interaction between semester and enrollment status for 46 cardiorespiratory endurance (P<0.001). This means that students enrolled in the physical education during the first semester performed significantly better during the pretest, this interaction shows the combined effect of semester and enrollment status. The final set of research questions focused on whether there was an effect of physical education enrollment on the students’ academic achievement. This final set of research questions included the following two specific questions: Research Question 7: Is there an effect of physical education enrollment (yes or no) on students’ academic achievement? Research Question 8: Is there an effect of physical activity level (no activity, some activity, activity meeting Healthy People 2010 guidelines) on students’ academic achievement? Due to the fact that there are no pretest data for grades, only midpoint and posttest data for combined scores are presented in Tables 4 and 5. Terra Nova percentiles are also shown in Table 4. The ANOVA source tables can be seen in Appendix I. 47 Table 4. Midpoint and posttest academic achievement variables (Mean 1 SD) Academic Achievement Physical Education Physical Education “mm“ 1" Semester (n-ioo) 2"“ Semester (n=114) ”i'fSemester (Midpoint) 33.4 1 6.9 32.5 1 7.5 Combined Score 7" Semester (Postteet) 33.1 1 7.7 32.2 1 6.9 Combined Score Terra Nova Percentiles 55.3 1 27.5 60.6 1 20.3 Results revealed that academic achievement (combined scores) was not affected by physical education class enrollment status, nor were the results of the Terra Nova test. However, students who performed vigorous physical activity at a level that met the Healthy People 2010 Guidelines achieved higher academic scores compared to the other students (P<0.05). There was no Significant difference in grades as a function of moderate activity during either semester. 48 Table 5. Distribution of grades, moderate, and vigorous physical activity (Mean 1 SD) 1it Semester 2fiir Semester Combined Score Combined Score Moderate Physical Activity 34.3161 30417.9 (1 =No activity) Moderate Physical Activity 33.7165 33.5168 (2=Some activity) Moderate Physical Activity 33.4176 33217.5 (3= Activity meeting Healthy People 2010 guidelines) Vigorous Physical Activity 32.9168 32.0175 (1 =No activity) Vigorous Physical Activity 35.5169” 31.61113 (2= Some activity) Vigorous Physical Activity 35.9159 35.115? (3=Activity meeting Healthy People 2010 guidelines) * Significantly different from vigorous physical activity (1) P<0.05 # Significantly different from vigorous physical activity (1&2) P<0.05 Data derived from the observational instrument System for Observing Fitness Instruction Time (SOFIT) were used to assess physical education classes. The two sixth grade physical education teachers were assessed four times over the course of the school year (twice per semester). These data are presented in Tables 6-8. 49 Table 6. Activity levels during physical education classes using SOFIT (% of class time) by semester Activity Level 1if Semester 2m Semester Average (%) (%) 1't and 2'“‘ Semester 1 = Lying down 0.0 0.0 0.0 2 = Sitting 32.0 37.9 34.9 3 = Standigg 31.4 28.9 30.1 4 = Walking 28.4 7.3 17.9 5 = Very Active 8.2 25.9 17.1 Table 7. Lesson Context Decisions during physical education classes using SOFIT (% of class time) Lesson Context 1“Semester 2“ Semester Average Decision (%) (%) 1't and 2"“I Semester Game 39.5 0.0 19.7 Fitness 0.0 7.1 3.6 Knowledge 29.2 37.5 33.4 Management 24.3 30.9 27.5 Physical Fitness 5.2 17.7 11.5 Skill 1.8 6.8 4.3 Table 8. Teacher Involvement Decisions during physical education classes using§OFlT (% of class time) Teacher 1it Semester ZWSemester Average 1F Involvement (%) (%) and 2"" Decision Semester Promotes Fitness 3.0 0.7 1.5 Instructs Generally 32.0 38.2 35.1 Manages 20.5 23.2 21 .8 Off-Task 9.1 6.8 7.9 Demonstrates 1 .8 0.0 0.9 Fitness Observes 33.6 31.1 32.4 50 The majority of the class periods were spent in activity level 2 (sitting). The level of moderate to vigorous physical activity can be determined by adding activity levels 4 (walking) and 5 (very active). The students spent 35% of the class period in moderate to vigorous physical activity (approximately 19 minutes). Although the average of moderate to vigorous activity was similar for both semesters, the physical education classes in the first semester spent more time in activity at level 4 and the physical education classes in the second semester spent more time in activity at level 5. The lesson context was primarily dedicated to management and knowledge, which is consistent with the amount of time the students spent Sitting or standing during the class periods. Teacher involvement was primarily comprised of management, general instruction, and observation. Based on personal observation, the physical education classes of both teachers were organized in a Similar fashion. 51 CHAPTER 5 DISCUSSION Three sets of research questions were included within this dissertation. The first set dealt with physical education and physical activity behaviors. The three specific questions included: Is there an effect of semester (first or second) of enrollment on students’ physical activity behavior outside of school? Is there an effect of physical education class enrollment (yes or no) on students' physical activity behavior outside of school? Is there an interaction between semester (first or second) and physical education class enrollment (yes or no) on students’ physical activity behavior outside of school? It was hypothesized that students enrolled in physical education during the first semester (summer and fall) would be more active outside of school than those enrolled in physical education class during the second semester (winter and spring). Also, it was hypothesized that students enrolled in physical education class would be more active outside of school compared to those not enrolled in physical education class. Results showed that there was no significant effect of physical education class enrollment on physical activity behaviors (Table 2). During the semester that students were enrolled in physical education, they performed the same amount of physical activity as those not enrolled in physical education. The findings in this study differ from those of Dale et al. 14 and Gordon Larsen et al. 19 who reported that students enrolled in physical education had higher out of school physical activity levels compared to those not enrolled in 52 physical education. These differences may be due to the variations in study design and physical activity assessments across the studies. In the present study, physical activity was assessed longitudinally using a questionnaire (3DPAR). The 3DPAR measured three days of physical activity and was completed three times over the course of the school year. The Dale et al. 14 study was cross-sectional and used accelerometry to assess physical activity for four consecutive days. Accelerometry may be a better method for assessing physical activity since it does not rely on children’s memories or ability to recall like the questionnaire. However, the cross sectional study design did not allow the authors to determine whether individual children's activity behaviors changed over the course of the year. The Dale et al. 14 study included participants that were 3'“I and 4th graders, who were younger than the 6th graders used in the present study. Due to differing ages, there may be different mechanisms involved in driving physical activity, which may make the results of the Dale et al. 14 study not applicable to the results found in the present study. Gordon-Larsen et al. 19 used a seven-day physical activity recall to assess physical activity, which was assessed only one time during the study. This study was also cross-sectional. Only a small proportion (~21%) of the students in the study had physical education class but the authors did not elaborate on this issue. It is possible that physical education was an elective class in the Gordon- Larson study 19. If so, students who chose physical education may have already been active or participating in sports. This possible sampling bias may have skewed the results. 53 In the present study, students’ out of class physical activity levels were slightly higher (not significantly) during the semester they enrolled in physical education class. SOF IT data showed about 19 minutes of physical education class was spent in moderate to vigorous physical activity, which translates into one 30-minute time block per day. If the activity during physical education (one 30-minute time block) is added to the outside of school activity levels, students enrolled in physical education would have a higher overall activity level compared to the students not enrolled in physical education. There was an effect of test date of assessment on the activity levels, regardless of the semester the students were enrolled in physical education class. The values for moderate physical activity obtained during the midpoint of the study were significantly lower than pretest and posttest values (Table 2). Vigorous activity levels were highest at pretest and significantly lower at midpoint and posttest. However, the midpoint values are similar to those reported by Weston et al. 72 Weston et al. developed and validated the previous day physical activity recall, which was modified into the 3DPAR. Physical activity values obtained during the validation study are comparable to the values in the present investigation. High pretest values may be attributed to residual activity from the summer and high posttest activity levels may be attributed to warmer temperatures and possibly an increased potential for outdoor activity compared to those available in the winter (midpoint). The differences among baseline, midpoint, and posttest activity values indicate that there may be a seasonal effect on the children’s activity levels. Michigan experiences extremes of all four seasons (i.e., cold, snowy winters, hot summers), which may be a reason for the differences in activity levels. Pivamik et al. 47 studied seasonal variation in physical activity performed by Michigan adults. The authors found that adults are more active in the spring and summer compared to the fall and winter. Ross et al. 49 looked at seasonal variation in physical activity in a national sample of children involved in the National Children and Youth Fitness Study I. They found that physical activity levels were highest in the summer, followed by the spring, and then the fall. Physical activity levels were lowest in the winter. These results are similar to the findings in the present study. Students were most active at the beginning of the study (August, September), very active at the end of the study (May, June) and least active at the midpoint of the study (January). Regardless of physical education enrollment, warmer weather during the fall and spring allows for more opportunities to be physically active and during the winter these opportunities are diminished due to adverse weather conditions. Results from this study also show that physical activity levels declined during the midpoint of the study (winter) and television watching increased. Colder temperatures and unfavorable weather conditions hamper a student’s opportunities to lead an active lifestyle. As the temperature warmed during the spring, physical activity levels increased and television viewing time decreased. This finding illustrates the importance of physical education class, especially during the winter. If students are provided with an opportunity to be active during the school day, they may be able to achieve recommended levels of physical 55 activity. Increased levels of physical activity during the school day may attenuate the effects of increased sedentary behavior outside of school during the winter months. The second set of research questions dealt with the effect of physical education class on health-related fitness levels. The research questions included: Is there an effect of semester (first or second) on students’ health- related fitness? Is there an effect of physical education class enrollment (yes or no) on students’ health-related fitness? Is there an interaction between semester (first or second) and physical education class enrollment (yes or no) on students’ health-related fitness? It was hypothesized that students enrolled in physical education class would have higher cardiorespiratory endurance than those not enrolled and that students who have physical education the first semester would have greater fitness than those enrolled in physical education class the second semester. The results revealed that there was a significant effect of semester on cardiorespiratory endurance. There was also a significant interaction between physical education class enrollment and semester. In a systematic review by Morrow and Freedson 40, the authors found that the overall correlation between physical activity and physical fitness was small to moderate (typical correlation r=0.16-0.17). In the present study, there was a significant effect of test time on cardiorespiratory fitness. PACER laps were highest at pretest. This may be a residual effect from the summer, a time when youth are most active, as was indicated by 3DPAR results. PACER laps were 56 significantly lower at midpoint (winter) and remained at levels similar to the midpoint at posttest. At midpoint and posttest, physical activity levels were lower compared to pretest. These levels of activity may have an effect on the fitness of the participants. The interaction between physical education enrollment status and semester reveals interesting findings. Students who were enrolled in physical education during the first semester achieved the highest level of cardiorespiratory fitness at pretest. Their values decreased at midpoint and then further decreased at posttest, which was the end of the semester they were not enrolled in physical education. Students enrolled in physical education during the second semester also achieved the highest number of laps during the pretest. Their cardiorespiratory endurance decreased at midpoint, which was the end of the semester they were not enrolled in physical education. However, their values increased at posttest, which was the end of the semester that they were enrolled in physical education. This small increase in laps performed by students enrolled in physical education during the first semester may have been due to an increased effort put forth by those students. Students in the study were encouraged by their physical education teachers to do their best. The participants may have put forth an extra effort in order to impress their teachers, who often asked how they performed during the testing. Participants evaluated during their physical education class were tested with classmates who were also participating in the study. Since these students were in class with each other everyday, there was probably some 57 level of competition within the group. This competition may have motivated these students to work harder, which may be a reason the students enrolled in physical education class performed better on the PACER. Participants who were not enrolled in physical education were tested during a variety of academic class times. Therefore, many students did not know each other, which may have led to a lower level of competition and lesser number of PACER laps completed. We determined the percentage of students who were in the Healthy Fitness Zone (HFZ) for each health-related fitness variable (Appendix J). Students most often achieved values that fell in the HFZ for sit-and-reach, followed by curlups, cardiorespiratory fitness, and percent body fat. The variable that had least number of students in the HFZ was pushups. These passing rates are similar to those found reported by Looney et al. 30 who analyzed data from the National Children and Youth Fitness Study l and II (NCYFS l and II). The authors found that the variable most often passed by these study participants was sit-and-reach. This was followed by percent body fat, cardiorespiratory fitness, situps, and pushups 30. The variable that differed most between the present investigation and that of Looney et al. was percent body fat, with a smaller percentage of students achieving HFZ in the present study. The data from the Looney et al. 30 study were collected approximately fifteen years ago. Since oveniveight and obesity levels in youth have been increasing over the past two decades 70, this may be a reason why fewer students achieved HFZ values compared to study participants in the NCYFS l and II studies. Even though our study participants were not a 58 national sample, our results support this trend toward increasing body fatness in youth. Prevalence of obesity using BMI was determined, 23.9% of participants in the current study were considered overweight and 13.2% were considered obese. Overall, 56% of all students in the current study were in the HFZ for percent body fat. The percentage of students in the HFZ for body fatness in the Looney et al. 30 study was 87%. The percentage of students in the HFZ for abdominal strength and endurance (curlups) was actually higher for both groups during the semester that they were not enrolled in physical education class. Overall, the students performed better at the beginning of the study. The differences at midpoint and posttest periods may be due to lack of effort by the participants. The curlup test was performed to the beat of a metronome, so the test took longer than most others and was more difficult in terms of technique and stress on the abdominal muscles. Many participants complained or said they were not going to perform to the best of their abilities at posttest, which may have altered the results. The percentage of students in the HFZ for upper body strength and endurance (pushups) and cardiorespiratory endurance (PACER) was increased during the semester that students were enrolled in physical education. Flexibility rates in the HFZ were high for both groups through all testing periods. Body composition (percent body fat) rates in the HFZ declined in both groups over the course of the study. This increase in percent body fat percentage was somewhat expected since the children were growing. 59 The final set of research questions examined the relationship between academic achievement and physical education class enrollment. The research questions included: Is there an effect of physical education enrollment (yes or no) on students’ academic achievement? Is there an effect of physical activity level (no activity, some activity, activity meeting Healthy People 2010 guidelines) on students’ academic achievement? It was hypothesized that students enrolled in physical education class would have greater academic achievement than those not enrolled in physical education class. Students who achieved Healthy People 2010 guidelines for physical activity would have the highest academic achievement. Academic achievement was assessed using grades from four core academic classes and standardized test scores (Terra Nova percentiles). Grades were converted to ordinal data (A=5, B=4, C=3, D=2, F=1) for each marking period. Grades for all four courses were summed over two marking periods each semester. Physical education class enrollment status did not affect how well the students performed in school. Academic achievement in core classes did not differ significantly as a function of the enrollment status in physical education. The reason for this finding may be due to the fact that activity levels during the physical education classes were quite low. Only ~19 minutes of the 55-minute Class period was spent in moderate to vigorous activity. This low level of activity may not be sufficient to cause an increase in academic achievement. 60 Shephard 55 suggests that increased physical activity during the school day may induce arousal and reduce boredom, which may lead to increased attention span and concentration during the school day. He also noted that increased activity levels might be related to increased self-esteem, which would increase classroom behavior as well as performance. There may be a threshold or certain level of activity necessary to produce these desired effects. This may be why increases in performance are seen with vigorous physical activity and not with moderate physical activity in the present investigation. Results from the Shepherd and Lavallee Trois Rivieres Experiment revealed that when students received an additional hour of physical activity per day, taught by a physical educator, they showed better academic performance compared to controls 57. These findings suggest that if students in physical education classes receive an adequate amount of physical activity during the class, they may perform better academically. Academic achievement in the Trois River Experiment 57 study was assessed using average grades for French, English, mathematics, natural science, and conduct. These subjects are similar to the core classes from which grades were derived for assessing academic achievement in this study. In the present study, an average of 19 minutes was spent in moderate to vigorous physical activity during physical education class. In contrast, subjects in the Shephard and Lavallee 57 study performed one hour per day of physical activity. This increased amount of physical activity during the school day may be 61 the reason the authors found higher academic achievement levels in students who had the physical education class. ' Grades and standardized test scores were also compared to physical activity levels. The amount of moderate physical activity performed by the students did not affect academic achievement. However, there was a significant effect of vigorous activity levels on academic achievement. During the first semester, when the study participants perfomied any amount of vigorous activity, they perfon'ned better academically compared to students who participated in no vigorous activity. In the second semester, only students who reached guideline goals recommended by Healthy People 2010 for vigorous activity perfomied better academically compared to students who performed none or only a small amount of vigorous activity (T able 5). These findings may indicate that a threshold of physical activity intensity is necessary to achieve higher levels of academic performance. Keays and Allison 27 reviewed the literature and found studies demonstrating the positive effects of daily moderate to vigorous physical activity on student performance and academic achievement. Academic achievement in individual studies was defined as memory, observation, problem solving and decision-making. These measures of academic achievement differed from those in the current study; however results still indicate that increased levels of physical activity lead to increased academic performance. The only study that provided comparable study design to the present study was the Tres Rivieres experiment conducted by Shephard and LaVallee 57. 62 In addition to evaluating grades in core subjects, standardized test scores were also analyzed to determine if physical education class enrollment or physical activity levels affected test scores. The standardized test was administered during the second semester (April). Although there were no statistically significant results, test scores appear to be higher for students who were enrolled in physical education class. On average, the students enrolled in physical education class during the second semester fared ~10% better on the exam (55.31275 (PE Semester 1) vs. 60.61223 (PE Semester 2)). Regardless of how much moderate activity was perfomied, academic achievement (standardized test scores) was virtually unaffected. It appears that students who do some vigorous activity performed better than those who performed no vigorous activity and those who met Healthy People 2010 guidelines for vigorous activity. As stated previously, there may be a threshold of activity intensity needed to bring about changes in the child that lead to an increase in academic achievement. The intensity level of vigorous activity may be necessary to meet that threshold. Sports participation could provide the opportunity for students to reach threshold intensity. In the present study, many participants performed vigorous activity through sports participation. Vigorous activity levels achieved during sports participation may provide an adequate intensity level to meet the threshold necessary to see effects of physical activity on fitness and academic achievement. During the first semester, 48.5% of students played on sports teams, with the majority playing soccer and football. During the second semester, only 37.5% of students played on sports teams, 63 basketball and indoor soccer were the sports of choice. At the end of the study, 39.5% of students played sports, with the majority being soccer and baseball/softball. Results Show that physical activity behavior has a greater effect on classroom performance than standardized test performance. Classroom performance included assignments, homework, and tests. Grades were given over the course of four marking periods as opposed to the standardized test, which is based on a single performance. These factors, along with others such as test bias or test-taking anxiety, may affect how well a child performs on a standardized test. In conclusion, the results indicate no significant relationship between physical education class enrollment and physical activity behaviors, cardiorespiratory endurance, or academic achievement and physical activity. Vigorous physical activity levels are positively (and significantly) related to higher academic achievement. Children may be more active over the course of an entire day as consequence of taking daily physical education. This increase in physical activity may contribute to the positive trends found between activity, fitness, and academic achievement in this study. A limitation of this study may be sample Size. Power analysis required 142 subjects in each group to achieve statistical power of 0.80. In the current study, we had 100 students in one group and 114 students in the other group. Physical education classes appear to be especially beneficial during the winter. Physical activity levels outside of school were lower in the winter 64 compared to the levels of physical activity in the spring and fall. Physical education classes during the winter give students the opportunity for daily physical activity for 55 minutes. This increase in overall physical activity may offset the increase in television watching that occurred during the winter. These study results also provide an impetus to improve current physical education programs in order to increase both moderate and vigorous activity levels during class. Future research should be conducted to determine the efficacy of physical education programs as well as the effects that increases in activity time and intensity during physical education classes have on physical activity levels outside of school, health-related fitness levels, and academic achievement. Future investigations examining the amount of time spent doing actual physical activity during class will give an indication of whether the classes are providing ample opportunity for children to achieve Healthy People 2010 goals for physical activity. The impact of physical education class on physical activity levels outside of school, health-related fitness levels, and academic achievement may vary depending on the amount of time spent being active. Studies examining intensity of activity during physical education classes may help answer questions on “work intensity thresholds” that may need to be met in order to have an effect on physical activity outside of school, health-related fitness levels, and academic achievement. 65 Appendix A 66 Appendix A Letters of Permission July 29, 2002 To: Dawn Podulka Coe From: Jerry Klomparens Principal, Harbor Lights School West Ottawa Public Schools Dear Dawn, This is to confirm approval of your research project at Harbor Lights School during the 2002 I 03 school year. I look forward to reading your findings in what I'm sure will be a valuable dissertation. Sincerely, Jerry Klomparens 67 Macatawa Bay School . Wimm Holand,M1 49424 Warm mimics-am ‘WWEIZJBM July 29, 2002 Dawn Podulka Coe Department of Kinesiology Michigm State University Dear Dawn, This is to confirm that you may continue your study which involved gathering data on and float our students. 8 cc Iy, Richard liter Primipal m u an Grade Assist-I W 1W 9“! 018*: Am W _ 786-2099 786-2099 786-20I9 'AWWWMMWsm’ -WsstOtta‘IuPublic8chools 68 Appendix B 69 hwum ”CHM him “It.” mu Appendix B Human Subjects Approval RE: [RBI 02-525 CATEGORY: EXPEDITED 2-4, 2-7 APPROVAL DATE: July 22, 2002 TITLE: THE IMPORTANCE OF PHYSICAL EDUCATION CLASSES IN RELATION TO PHYSICAL ACTIVITY BEHAVIORS, PHYSICAL FITNESS, CARDIOVASCULAR DISEASE RISK FACTORS, AND ACADEMIC ACHIEVEMENT The University Committee on Research Involving Human Subjects’ (UCRIHS) review of this projediscanpletemdlanpleaeedbedvbethatflndghtsandwdfareofflnm subjects appear to be adequately protected and methods to obtain informed consent are appropriate. Therefore. the UCRIHS appreved this project. RENEWALS: UCRIHSapprovallsvdldforonecdaidaryea'.Mgmmngwithflnapprovddate shownabove. Prolactsconflmhgbeyondonewarmustberenewedufiththagreairerm form. Amaxlmumofloureuchexpedited renewals possible. lnvesiigatorswishlngtooontlrxiea projectbeyondthatfimeneedtowbmitltagahforacompletereview. REVISIONS: UCRIHS mudrevlawanydianges In procedures Involving human subjects. prior toinifiatlonofthechmge. Ifthislsdoneatthellmeofrenewal,pleaseuselhegieenienanal form. Torevhemapprwedprdoodatenyothertinedtmtheyaeerdmwrltui requestbfiwUCRlHSChaknequesthgmflsedappmdandrdmingflnpojedisBs and title. lndudehyaxrequesladasaipflonofmechangemdmyrevisedlnmnents. corieentformsoradvertisementsthatareapplicable. PROBLEMSICHANGES: Shouldeitharofihefollmrlngalsedufingtheootneofthem notify UCRIHS promptly. 1) problarns (unexpected side effects. complflrts, etc.) hvolvhg hummsubjedsa2)chmgcsinmemseuchmnaxunewhfmnubniidccdng greaterrbkthmanwbjecflflnnathedMnnflnpmtocdwasprefiwdymiewedw approved. lfwecanbeoffurtheraeslslance, pleasecontactusat(517)355-21800rviaemalz UCRIHSQmeusw. PIeasenotethatallUCRlHSfomrsarelocatedontheweb: httdewwmsuedu/userlticrlis flaw Ashir Kumar. MD. ‘ UCRIHS Chair AKzrt 60: Dawn Podulka Coe 3 IM Sports Circle 70 Appendix C 71 Appendix C Consent Form Investigators: James M. Pivamik, PhD. (5l7)353-3520 Dawn P. Coe, M.A. (616)738-l530 INFORMED CONSENT Title: The importance of physical education class in relation to physical activity behaviors, physical fitness, cardiovascular disease risk factors, and academic achievement. Many researchers are interested in finding out how physical education class relates to physical activity behaviors in children and adolescents. Physical activity is related to physical fitness as well as risk factors for cardiovascular disease. The purpose of this study is to find out your son/daughter‘s physical activity behaviors, aerobic fitness level, and measure other variables that may be related to cardiovascular disease. Your son/daughter is eligible for this study because slhe will be enrolled in 6‘, 7‘, or 8" grade in the West Ottawa School District. His/her participation is completely voluntary. Your child will perform a number of physical fitness tests. These include: a shuttle run for aerobic fitness a curl up test for abdominal strength a push-up test for upper body strength a sit and reach test for flexibility a measure of height and weight cpinchofthearmandlegtoestimatebodyfamess In addition, the investigators will determine your child’s blood pressure by the usual method of placing a cuff around his/her arm. Finally, your child will be asked a few questions about smoking behavior and physical activity behavior. All tests will be performed at school, either during physical education class or during a free period. Total time for the test should not exceed two class periods per semester. There are possible risks in the study. However, they are very minimal. The physical fitness tests are similar to those administered as part of a typical physical education curriculum. All researchers involved with the testing have been trained in either advanced or basic cardiopulmonary resuscitation (CPR). The investigators have extensive experience in working with children. Dr. Pivamik has worked with children for a number of years while serving as the Director of the Wellness Center at Texas Children‘s Hospital in Houston, Texas and through numerous research projects involving children while at MSU. Dawn conducted research involving children during her master’s program and for the past three years while working at MSU with Dr. Pivamik. A record of your child’s participation in the study will be kept in a confidential file at Michigan State University. The confidentiality of the data will be maintained to themaximum extent allowable by law and will not be shared with any personnel in the school. S/he is free to withdraw from the study at any time for any reason. Such withdrawal will not jeopardize your child's future treatment. There will be no cost to you or your child for participating in this study, and all participants will receive information about their physical fitness and other health related measures obtained. When slhe completes the study, your son/daughter will receive either an MSU t-shirt or complimentary movie passes for his/her participation. In the event of injury resulting fiom this research, parents or guardians assume responsrbility, since Michigan State University is notable to offer financial compensation nor to absorb the costs of medical treatment. However, necessary facilities, emergency treatment and professional senrices will be available to research subjects, just as they are to the community generally. Your signature on the following page, and your child‘s signature, acknowledges his/her voluntary participation in this research project. Such participation does not release the investigators, institutions, sponsor, or granting agency from their professional and ethical responsibility to your child. If you have any questions about this study, please contact the investigators [Dr. Pivamik (iimpixMedu, 5lT-353-3520) or Dawn Coe (Mulkadmmedg, 6I6-738-I530)]. If you have questions or concerns regarding your rights as a study participant, or are dissatisfied at any time with any aspect of this study, you may contact - anonymously, if you wish - Ashir Kurnar, M.D., Chair of the University Committee on Research Involving Human Subjects (UCRIHS) by phone: (517) 355-2 I 80, fax: (517)432-4503, e-mail: yorilg@g§u.edu, or regular mail: 202 Olds Hall, East Lansing, MI 48824. 72 James M. Pivamik. Ph.D. (5 l 7)353-3520 Investigator: Dawn P. Coe, MA. (6l6)738~l530 Please print your name, and the name of your child in the spaces below. I, , the parent/guardian of , grant permission for my son/daughter to participate in the study. My child will have the Opportunity to ask the researchers questions about this study before participating in this study. Parent or Guardian Signature Date Address Phone Number Address Mirror's assent to participate Study Participant Signature Date Date Investigator Signature 07/ 1 7/02 UCRIHS APPROVAL FOR THIS project EXPIRES: 'JUL 2 22003 SUBMIT RENEWAL APPLlCATlON ONE MONTH PRIOR TO ABOVE DATE TO CON l INUE 73 Appendix D 74 Appendix D Three Day Physical Activity Recall Activities Scale This purpose of this questionnaire is to estimate the amount of physical activity that you perform. The name of each day (Tuesday, Monday, and Sunday) that you will describe is located in the top right hand corner of each time sheet. 1. For each time period, write in the activity number that corresponds to the maln activity you actually performed during that particular time period. 2. Then rate how physically hard each activity was. Place a V" in the timetable to indicate one of the following intensity levels for each activity. - Llht -8low breathing, little or no movement. ~m - Normal breathing and some movement. Hm olncreased breathing and moderate movement. WT Hard- Hard breathing and quick movement. fi’ @% 75 Activity Numbers Eating I.) Eatingameal 2.) Snacking Work 3.) Working (e.g., part-time job, child care) ("8!) 4.) Doing house chores (e.g., vacuuming, dusting, washing dishes, animal care, etc.) 5.) Yard Work (e.g., mowing. raking) After SchoellSpare 'l'imel Hobbies 6.) Church 7.) Hanging around 8.) Homework 9.) Listening to music 10.) Marching band/flag line/(kill team ll.) Music lesson/playing instrument I2.) Playing video games/surfing Internet 13.) Reading 14.) Shopping 15.) Talkingon phone 16.) Watching TV or movie Transportation l7.) Riding in a cadbus I8.) Travel by walking l9.) Travel by bicycling Sleep/Bathing 20.) Getting dressed 21.) Getting ready (hair, make-up, etc.) 22.) Showering/bathing 23.) Sleeping Sample activity time sheet: School 24.) Club, student activity 25.) Lunch/free time/study hall 26.) RE. class 27.) ROTC 28.) Sitting in class Physical Activities and Sports 29.) Aerobics/aerobic dancing 30.) Basketball 31.) Bicycling 32.) Bowling ' 33.) Calisthenics(i.e., jmnpingjacb. sit-ups) 34.) Cheerieading 35.) Dancing (social, recreational) 36.) Dancing (ballet, jazz, modem, tap) 37.) Field hockey 38.) Frisbee 39.) Golf 40.) Horseback riding 4l.) Ice/roller skating 42.) Jogging/running 43.) Karate/judo/nnrtial artsl self-definse 44.) Rollerblading 45.) Skateboarding 46.) Soccer 47.) Softball/baseball 48.) Stationary exercise machines (e.g., cycle, ski machine, stair climber, treadmill) 49.) Street hockey 50.) Swimming, water exercise 51.) Tennis 52.) Volleyball 53.) Walking (briskly) 54.) Weight/circuit training 55.) Other (list) The table below shows the correct way to fill out the activity time sheets. Note that only one intensity level is checked for each activity. Activity tit-um Lila Ioderate m Very Hard 7:00-7:30 22 / 7:30-8:00 21 / 8:00-8:30 18 '/ 8:30-9:00 28 ‘/ 9:00-9:30 28 f 9:30-10:00 28 F 10:00-10:30 28 / 76 Puta'l'toratethe Pagans...“ MON DAY ”2,2,3,ng TUESDAY Appendix E 80 Appendix E Supplemental Questionnaire 1. Do you play on any sports teams? Which ones? How often? 2. Do you go to physical activity classes (dance, martial arts, etc.)? Which ones? How often? 3. How much time do you spend watching television per day (minutes)? 81 Appendix F 82 Appendix F System for Observing Fitness Instruction Time (SOFIT) SOFIT Categories Phase 1. Student activity decision-What is the physical nature of an individual learner's engagement? What is his or her activity level? (1) lying down (2) sitting (3) standing (4) walking (5) very active Phase 2. Lesson context decision-What is the context of the lesson? How is time allocated for the class as a whole (at least 51% of the students)? (M) Management (K) General Knowledge (P) Physical Fitness Knowledge (F) Fitness (S) Skill Practice (G) Game Play Phase 3. Teacher involvement decision-What is the teacher doing? (P) Promotes fitness (prompts, encourages, praises) (D) Demonstrates fitness (models) (I) Instructs generally (M) Manages (O) Observes (T) Off-task Abbreviated Coding Form Interval Student activity Lesson context Teacher behavior 1 12345 ,MKPFSG POIMOT 2 12345 MKPFSG POIMOT 1 12345 MKPFSG POIMOT 2 12345 MKPFSG POIMOT 83 Appendix G Appendix G ANOVA Source Tables for Table 2 ANOVA Source Table for PE Class and Moderate Physical Activity Source df PE Semester 1 Subjects 208 Test Date 2 Interaction 2 Error 372 Total 585 $8 131.35 17723.62 1305.08 41.05 17387.19 36480.25 MS F ratio P value 131.35 2.81 0.2160 85.21 1.82 <0.0001 652.54 13.96 <0.0001 20.53 0.44 0.6449 46.74 ANOVA Source Table for PE Class and Vigorous Physical Activity Source dt PE Semester 1 Subjects 208 Test Date 2 Interaction 2 Error 372 Total 585 88 5.57 5378.59 278.70 16.64 4694.31 10418.94 85 MS F ratio P value 5.57 0.44 0.6395 25.86 2.05 <0.0001 139.35 1 1 .04 <0.0001 8.32 0.66 0.539 12.62 Appendix H 86 Appendix H ANOVA Source Table for Table 3 Source df SS HS F ratio P value PE Semeaer 1 206.99 206.99 4.44 0.4511 Subjects 212 76352.40 360.15 7.73 <0.0001 Test Date 2 330.76 165.38 3.55 0.0296 Interaction 2 635.83 317.92 6.83 0.0012 Error 420 19560.43 46.57 Total 637 97149.86 87 Appendix I 88 Appendix I ANOVA Source Tables for Tables 4 and 5 ANOVA Source Table for Moderate PA and First Semester Grades Source df Moderate PA 2 Error 191 Total 193 SS 1 1 .43 8787.05 8798.48 IS F ratio P value 5.72 0.12 0.8833 46.01 ANOVA Source Table for Vigorous PA and First Semester Grades Source df Vigorous PA 1 Error 191 Total 193 $3 284.18 8514.30 8798.48 MS F ratio P value 142.09 3.19 0.0435 44.58 ANOVA Source Table for Moderate PA and Second Semester Grades Source df Moderate PA 2 Error 185 Total 187 $3 133.93 10223.56 10357.49 MS F ratio P value 66.97 1 .21 0.3000 55.26 ANOVA Source Table for Vigorous PA and Second Semester Grades Source df Vigorous PA 2 Error 185 Total 187 33 348.61 10008.88 10357.49 89 MS F ratio P value 174.31 3.22 0.0421 54.10 Appendix J 90 Appendix J Percent of student in the Healthy Fitness Zone for FITNESSGRAM tests 8 S S No 8 B .2“. 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