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F'— DATE DUE DATE DUE DATE DUE __ MSU Is An Affirmative Action/Equal Opportunity institution czblmmedtnpms-oi THE EFFECT OF BODY COMPOSITION TESTING ON ADHERENCE TO A SIX MONTH BEHAVIORAL WEIGHT LOSS PROGRAM AT THE WORKSITE BY Frederick W. Danziger A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF ARTS Department of Physical Education and Exercise Science 1991 688- 3&3??? ABSTRACT THE EFFECT OF BODY COMPOSITION TESTING ON ADHERENCE TO A SIX MONTH BEHAVIORAL WEIGHT LOSS PROGRAM AT THE WORKSITE BY Frederick W. Danziger The purpose of this study was to determine the effects of body composition assessments on adherence to a six month behavior modification weight loss program. Ten healthy females (age 25-53 yrs) served as subjects who received both the behavioral weight loss treatment and body composition testing (EXP). Ten similar females (28-60 yrs) underwent an identical weight loss treatment without body composition assessments and served as controls (CON). The EXP subjects had skinfold, body circumference, and hydrostatic weighing measurements taken before, at 3 months, and after the six month intervention. Repeated measures ANOVA revealed no statistically significant changes in any of the body composition parameters over 6 months in the EXP group. CON adherence (81.6 i 4.3%) was significantly greater (p < 0.01) than that of EXP (52.6 i 6.0%). Similarly, weight loss of CON (6.3 i 1.4 kg) was significantly greater (p < 0.05) than EXP's (1.8 f 1.4 kg). Therefore, body composition testing did not increase adherence to a six month weight loss program. DEDICATION To my parents, whose extraordinary amount of support and encouragement have made all of my educational endeavors possible. ii ACKNOWLEDGMENTS I wish to express my appreciation to Dr. Marc Rogers, my advisor and committee chairman, for not only making this research possible, but also for his assistance in all aspects of my graduate education. He has been my mentor and friend throughout my graduate program. I also wish to thank my other committee members: Dr. Brian Mavis, especially for his help with the psychological aspects of this study, of which I knew little, and Dr. Carol Rodgers, whose valuable suggestions and editing of the manuscript are greatly appreciated.) Bob Wells, coordinator of the Center for the Study of Human Performance, provided invaluable technical services during the body composition assessments. His help ensured the smooth operating of all the testing procedures. Finally, special thanks need to be given to Laurie Kaner for her belief in me when I had doubts. Her emotional support was imperative to the completion of the study. iii LIST OF LIST OF LIST OF Chapter I. II. TABLE OF CONTENTS Page TABLESOOOOOOOO000.00.00.00... ..... OOOOOOOOOOOOOOOOVi FIGURESOOOOOOOOO 00000000 0.0.0..OOOOOOOOOOOOOOOOOOVii APPENDICES. O O O O O O O 0000000000000 0 .......... O O O O O OViii INTRODUCTION ................ . ................ ...1 The PrOblemO O O O O O O O 0000000000000 O O O 0 0 O O O O O O O O O O O 4 Purpose of the Study... .............. ...........5 ResearCh Hypotheses. O O O O O O O O O O 0 O O O O O O O O O O O O O O O O 5 Research Plan............. ........... ...........7 Limitations of the Study........................8 REVIEW OF LITEMTIIRE ........ 0.0.0.000000000000009 Behavioral Aspects of Weight Loss...............9 The Evolution of Behavioral Weight Loss Programs.................................10 The Current Status of Behavioral Weight Loss Programs..... ...... ................13 The Role of Social Support Systems........14 Spousal Influence of Weight Loss.....15 Factors Affecting the Success of Social Support Systems..............16 Peer Support and Weight Loss.........18 Peer Support and the Worksite........18 Weight Loss Competitions at the Worksite............................19 The Role of Monetary Contracts ......... ...20 The Effects of Monetary Contracts on weight LOSSOOOOOOOOOOOO ...... 0.00.0021 The Effects of Monetary Contracts on Attrition...........................22 The Problem of Attrition..................23 Attrition and the Worksite...........24 Attrition and Exercise Programs......25 Knowledge of Results and Weight Loss ...... 26 Physiological Aspects of Weight Loss. .......... 28 Weight Loss and Body Composition ...... ....29 Indices of Bod Composition...............31 Hydrostatic We1ghing.................31 Skinfolds.......... ........ .. ..... ...32 Body Mass Index ...................... 34 iv Circumference Measurements...........34 summarYOO...0000......OOOOOOOOOOOOO0.0.0.0.0...35 III 0 RESEARCH METHODS O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 37 Research Design................................37 Subjects.......................................38 Weight Loss Program............................39 Assessment of Body Composition.................41 Body Mass Index...........................42 Body Circumferences.......................42 Skinfolds.................................43 Hydrostatic Weighing......................45 Data Collection Schedule..................47 Statistical Analyses...........................49 IV. RESULTS AND DISCUSSIONOOOOOOO0.00.000000000000050 Subject Characteristics........................50 Skinfold and Circumference Measurements........51 Body Composition...............................53 Weight Loss....................................54 Adherence......................................57 Discussion.....................................61 V. SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS......73 summary. 0 O O O O O O O 0 O O O O O O O O O O O O O O O O O O O O O O O O O O O O O .73 conClus ions 0 O O O O O O O O O O O O O O 0 O O O O 0 O 0 O O O O O O O O O O O O O 74 Recommendations................................74 APPENDICESOO...OOOOOOOOOOOOOOOO0.. ......... 0.0.0000000000075 REFERENCES...................... ................... .......98 LIST OF TABLES Page Subject Characteristics..............................51 Effects of Weight Loss Program on Average Skinfold Thickness for EXP Group..............................52 Effects of Weight Loss Program on Average Circumference Measurements at Three Sites for EXP GrouPOO0.00...0.0.0....OOOOOOOOOOOOOOOOOOOO0.00......53 Effects of Weight Loss Program on Body Weight, % Body Fat, and Lean Body Mass for EXP Group................54 Effects of Weight Loss Program on Body Weight for EXP and CON GrouPSOOOOOOOOOOOOOOOOOOOOOOOOOO...OOOOOOOOOOSS Correlation Coefficients of Body Composition Measures and Program Measures for EXP Group.................. 60 vi LIST OF FIGURES Figure Page 4.1 Weight Loss Over Six Months in EXP and CON Groups....56 4.2 Contract Adherence to the Six Month Program for EXP and CON GrouPSOOOOOOOOOOOOOOOOO00.0.0000000000000000058 vii LIST OF APPENDICES Appendix - Page A. Informed Consent Form........... ................. .....75 B. Circumference Measurement Techniques.. ............... .77 C. Skinfold Pilot Study Data.............................78 D. Skinfold Regression Equations... ......... . .......... ..79 E. Hydrostatic Weighing Formulas ........ ....... ....... ...80 F. Diagram of the Hydrostatic Weighing System............82 G. Body Composition Data Collection Sheets ............... 83 H. Individual Summary of Results Form. ............ . ..... .85 I. Raw Data..............................................86 J. Repeated Measures Analysis of Variance Tables ......... 93 K. Program Evaluation Data....... .......... ..............96 viii CHAPTER I INTRODUCTION Obesity has been associated with inordinate mortality (Armstrong, Dublin, Wheatley, & Marks, 1951; Build Study, 1979; Lew, 1961). It is considered to be a risk factor for cardiovascular disease, hyperlipidemia, diabetes mellitus, hypertension, respiratory and gallbladder disease, arthritis, gout, and cancer. The prevalence of obesity in the United States is widespread, with 15-50% of the population considered to be obese (Bray, 1976). Therefore, the impact of being overweight on human health is substantial. The treatments used to contend with obesity vary considerably in their methodology. Such treatment strategies include exercise, caloric restriction/dieting, surgery, and pharmacological therapy. Before behavioral weight loss programs, weight reduction was considered to be, by at least one expert, a futile effort (Stunkard, 1958). Today, behavior modification is viewed as one of the most effective forms of obesity treatment (Buckmaster & Brownell, 1988). Early behavioral weight loss programs reported in the literature focused primarily on techniques such as self- monitoring and stimulus control (Ferster, Nurnberger, & Levitt, 1962; Stuart, 1967; Wollersheim, 1970; Hagen, 1974). Although some of these programs yielded some of the most impressive results to date, their research designs left many extraneous variables uncontrolled. Yet as research designs continued to improve, results still showed marked success in behavioral programs over traditional approaches such as psychotherapy. A review of current behavior modification programs has found such programs to result in a weight loss of about 1.0 to 1.5 pounds per week (Buckmaster & Brownell, 1988), which appears to be an optimal rate of weight loss (American College of Sports Medicine, 1985). Yet today's programs are not without problems. One of the greatest obstacles is that of attrition, with approximately 50% of participants dropping out within several months (Dishman, 1982). In an attempt to increase participant motivation as a way of. combatting attrition and enhancing weight loss, various incentive and support schemes, such as social support, monetary contracts, and group competitions have been employed. In general, such tactics are successful at lowering attrition and promoting weight loss (Buckmaster & Brownell, 1988). The worksite is an environment that may provide readily accessible peer support to foster health promotion. Unfortunately, worksite programs have been found to have notoriously high attrition rates, with one program reporting an 82% dropout rate (Stunkard & Brownell, 1980). Often these program result in minimal weight loss (Foshee, McLeroy, Summer, & Bibeau, 1986; Glanz & Seewalk-Klein, 1986; Stunkard & Brownell, 1980). To help combat these problems, many worksite programs have turned to using group competitions as a way of capitalizing upon the natural social networks that develop at the worksite. One study reported that by using competitions between different companies, as well as other motivational tools, an attrition rate of about 1% could be obtained (Brownell, Cohen, Stunkard, Felix, & Cooley, 1984). Group competitions are also an effective tactic for promoting weight loss and company morale, as well as curbing attrition (Stunkard, 1989). An additional, and usually effective, method of enhancing motivation is the use of monetary contracts. The success of such strategies appear to be dependent on the amount of money invested and the specific goals that are contracted for by the participant. The more money which is deposited, the greater the likelihood of success (Eufemia & Wesolowski, 1985). Also, if attendance is specified by the contractual agreement, then this is what will be achieved, and not necessarily weight loss. As previously mentioned, the success of the early behavioral weight loss programs was partly due to the knowledge of results of self-monitoring techniques (Kazdin, 1989). Participants recorded results of daily fluctuations in body weight, waist girth, and caloric intake. Using more sophisticated body composition assessments (e.g., hydrostatic weighing skinfolds, etc.) as monitoring techniques to enhance weight loss has yet to be studied, and is the focus of the present investigation. Body composition may be assessed by a number of non- invasive techniques. Hydrostatic weighing is generally considered the most accurate of these methods, and is often referred to as the "gold standard". Other non-invasive methods, such as anthropometric techniques, have been designed on information from hydrostatic weighing. The anthropometric measurements may be of great value for providing informative feedback on body fat distribution and the location of fat loss (McArdle, Katch, & Katch, 1991). The Problem While the use of physiological testing in health promotion programs is believed by some to be a powerful motivator to enhance adherence (Franklin, 1988), no studies have specifically evaluated such a claim. Behavioral exercise programs that utilize monetary incentives, peer support and the writing of contracts have been shown to increase exercise adherence rates to about 95% over a program duration of six months. Such programs have included graded exercise testing and body composition assessment before and after the intervention (Robison et al., 1991). There is a need, then, to ascertain whether the participant's knowledge of the results of such testing is a crucial component to increasing the compliance to health promotion programs. ‘ The final criterion for most behavioral weight loss programs is a reduction in total body weight. Thus, body composition measurements are seldom conducted. However, decreases in body weight that can be attributed to losses in water and/or lean body mass are undesirable, as they are usually only temporary and provide little health benefits. Also, if losses of water and lean tissue are extreme, serious health risks may be encountered. Although it is assumed that optimal fat loss will occur with a 0.5-1.5 lb/week weight loss, verification is needed in behavioral weight loss programs. Assessment of body composition may therefore aid in determining if an individual is losing weight properly. Also, when anthropometric indicators of body composition are utilized, verification of the anatomical location of fat loss can be obtained. Overall, individuals who participate in weight loss programs may substantially benefit from having their body composition assessed rather than just scale weight. Unfortunately, the few behavioral weight loss programs that reported body composition data have used techniques which provide only crude estimations, such as height/weight tables (Coates, Jeffery, Slinkard, Killen & Danaher, 1982) or circumference measurements (Hermann-Nickell & Baker, 1989). Such techniques are frequently utilized merely as a screening procedure to determine eligibility into the weight loss program. Purpose _§ the Study This investigation was designed to determine (a) the effects of body composition testing on adherence to a behavioral weight loss program at a university worksite and (b) the effects of such a program upon body circumference measurements, skinfold measurements, and percent body fat in sedentary, middle-aged women. Research Hypotheses The topic of the current research was a novel method of enhancing an individuals motivation to adhere to a weight loss program. It was hypothesized that the use of pre, mid and post program body composition testing of participants in a behavioral weight loss program that incorporated monetary incentives would enhance adherence to the program. Monetary contracts stipulated a 0.5-1.5 lb weight loss per week. It was hypothesized that body composition testing would provide participants with greater informational feedback of their weight loss efforts. Such assessments may increase motivation by providing additional feedback as to the amount of body fat lost (vs. lean mass or water lost), and where the fat loss has occurred. In this way, participants are provided with much more information concerning their weight loss efforts than is available with only knowing changes in total body weight. This type of feedback is known as knowledge of results (KR), which has been found to have substantial motivating effects, particularly in the field of motor learning (Newell, 1976). Since proper weight loss is a slow process requiring much perseverance, new motivational tactics should be attempted. The use of body composition testing to provide knowledge of results and feedback has yet to be applied in a weight loss program setting. This study was designed to test the following hypotheses: 1. Weight loss adherence rates would be significantly higher in a group that has body composition assessment in addition to participation in a behavioral weight loss program, compared to those participating in a behavioral weight loss program without body composition assessment. 2. Body circumference measurements, skinfold measurements, and percent body fat would be significantly lower after a six month behavioral based worksite weight loss program. Research Plan The sample consisted of 20 women volunteers from two worksite units on the Michigan State University campus. The subjects were between 25 and 60 years of age and free from any medical abnormalities that would prohibit a weight loss of 0.5 to 1.5 pounds per week. Ten subjects from Worksite A received pre, mid, and post-treatment body composition analysis and were assigned to the experimental (EXP) group. The body composition measurements consisted of skinfolds from six sites (tricep, bicep, suprailiac, umbilical, and thigh), body circumferences from three sites (abdomen, buttocks, and calf), and hydrostatic weighing. Data for a control (CON) group, which had demographic characteristics (age, sex, employment level) similar to EXP, were selected from a previous weight loss program conducted on the MSU campus. These ten female participants received the same behavioral treatment with no body composition assessment. The behavioral weight loss program, for all subjects, consisted of weekly meetings where participants were weighed and an educational lecture of relevant weight loss topics was presented. To enhance motivation, monetary contracts that stipulated a weight loss of between 0.5 and 1.5 pounds per week were used. In addition, subjects at each worksite (EXP and CON) were divided into teams of five individuals who competed against each other for forfeited money from other participants failing to adhere to their weekly contract. Differences in initial, three month, and six month body composition measurements of the experimental group, and body weight of both groups, were determined by a one way repeated measures ANOVA. Adherence rates between experimental and control groups were analyzed using independent t-tests, with the level of significance chosen at the .05 level for all tests. Limitations 9: The §§ggy The following difficulties and limitations were inherent in this study: 1. Different leaders ran the weight loss programs at the EXP and CON worksites. 2. Subjects in the EXP and CON groups were not randomly assigned, nor were their worksites. 3. Since subjects in the EXP and CON groups consisted of volunteers from different worksite units, these groups may have been substantially different from each other. 4. A relatively small sample size. CHAPTER II REVIEW OF LITERATURE The literature related to this study has been divided into two basic parts: (a) behavioral aspects of weight loss, which reviews the various influences on the development and success of behavioral based weight loss programs, and (b) physiological aspects of weight loss, which reviews the physiology of weight loss and introduces the techniques for evaluation that were used in this study. Behavioral Aspects pf Weight Loss A statement about the long track record of unsuccessful weight loss programs was formulated over 30 years ago by A.J. Stunkard (1958) when he rendered a most cynical judgment: "Most obese persons will not enter treatment for obesity. Of those who enter treatment, most will not lose weight and of those who do lose weight, most will regain it". Before the initiation of behavior modification techniques, attrition rates of between 20 to 80 percent were common for weight loss programs. Of those individuals who did remain in treatment, only 25 percent lost more than 20 lbs. and only 5 percent lost as much as 40 lbs (Stunkard & McLaren-Hume, 1959). 10 Tee Evolution pf Behavioral Weight Lpee Programs The use of behavior modification techniques in weight loss programs stems from the work of Schachter, who believed that the obese are stimulus-bound to overeat. He theorized that cues from the environment controlled eating, rather than the existence of any psycho-pathological state (Schachter, 1971). His theory suggested that these external stimuli overrode an individual's internal satiety mechanism, thus making the eating process difficult to stop (Schachter, 1971). Ferster, Nurnberger, and Levitt (1962) were the first to report the effects of behavior modification techniques on weight loss. Their program consisted of various self- control techniques of eating behavior such as stimulus control, self-reinforcement and punishment, controlled deprivation, response chaining, and other modern therapy treatments. Unfortunately, results from this study were never published, but the researchers suggested that the treatment effects were not substantial. In accord with Schachter (1971), however, the authors hypothesized that obese people eat in response to external cues and in a way that causes them to overeat. In 1967, Richard Stuart presented his now landmark study "The Behavioral Control of Overeating" (Stuart, 1967). The experiment consisted of a one year, multifaceted behavioral treatment program for eight case study subjects that followed all of the behavioral techniques laid down by Ferster et al (1962). Subjects in the study were all judged to be obese by their physician with their weight between 172 11 and 224 lbs. at the start of the program. Results showed that 30 percent of Stuart's subjects lost more than 40 lbs., and 60 percent lost more that 30 lbs. This was a dramatic improvement over the results of previous weight loss studies (Stunkard & McLaren-Hume, 1959). In fact, these results were considered to be the best ever reported for the outpatient treatment of obesity (Stunkard, 1972). Few researchers since have been able to duplicate the results of Stuart. An incredible explosion of research has followed Stuart's original work (1967), with hundreds of studies being conducted using behavioral treatments for obesity. Unfortunately, the research design of the early behavioral experiments was quickly found to be defective. While the results of Stuart's (1967) investigation were certainly impressive, the validity of Stuart's study was questioned because no control group was employed. In 1969, Harris accounted for this weakness by assigning subjects to either behavioral treatment, or a no-treatment control. The behavioral treatments subjects lost an average of 10.5 lbs., while the control subjects gained an average of 3.6 lbs. The study showed that the behavior modification techniques resulted in significant decreases in the temptation to eat large meals as well as to overeat. Also, there was a low attrition (drop out) rate of approximately 13% in the behavioral group. It was soon realized, however, that subjects in the behavioral group were given much more personal attention than the no-treatment controls. In order to control for this extra attention given in the behavioral weight loss studies, Wollersheim (1970) established a protocol that contained four experimental 12 conditions: (a) 'Focal' or behavioral treatment, (b) 'Non- specific therapy' which did not deal with specific behavioral concerns, (0) 'Social pressure' or positive expectation, and (d) a no-treatment control group of persons to receive treatment later. Eighty college female subjects were treated by four therapists over a three-month period. Results showed that the behavior therapy group lost more weight at post-treatment and two-month follow up than those in the control group. Also, the behavior group lost significantly more weight than the other groups, who themselves lost a significant amount weight. Improvements in the experimental designs of such studies were still forthcoming. Although the use of a placebo group accounted for the amount of personal attention given to subjects, it did not control any biasing factors of the researcher. Penick, Filion, Rox, and Stunkard (1971) took this into consideration when they deliberately biased two treatment groups for weight loss. A very experienced therapist was used for a traditional psychotherapy control group, while the experimental behavior modification group's therapists had little clinical experience. The behavior modification group still lost twice as much weight as the other group, who's weight loss was equivalent to that of more traditional psychotherapy methods. Therefore the added attention given to participants of behavior modification based programs was not a factor in the early success of such programs. The next question to be addressed in behavioral weight loss research was to determine whether the content of the actual treatment was as important as the influence of the 13 therapist. Hagen (1974) essentially replicated Wollersheim's (1970) study in an attempt to answer this question. Ninety mildly overweight female college students were randomly assigned to one of four experimental groups: (a) behavior modification, (b) bibliotherapy, the use of a written manual containing a behavior modification program mailed weekly to subjects, (c) both group and bibliography treatment, and (d) deferred-treatment control. Findings revealed that there was no difference in weight loss between the manual only group and the therapist treatment group, with each group losing an average of 12 lbs. The combined treatment yielded a slightly greater, but insignificant, weight loss. Thus, the study seemed to indicate that behavior modification techniques used are more influential than the effects of a therapist in terms of weight loss. Studies which followed have verified the results of Hagen (1974) by showing that bibliotherapy was as effective as group therapy (Ferstl, Jokusch, & Brengelman, 1975; Hanson, Borden, Hall, & Hall, 1976). Today, behavior therapy is the most widely used formal treatment in the United States for obesity (Bray & Gray, 1988; Brownell, 1989; Foreyt & Kondo, 1984), and has been viewed as the most effective of all nonsurgical treatments for weight loss (Stunkard & Penick, 1979). The basic components of modern behavioral approaches to weight loss include (a) self-monitoring and analysis of behavior; (b) stimulus control, or restricting external cues that set the occasion for overeating or remaining sedentary; 14 and (c) reinforcement of altered behavior (Glanz, 1985). The aim of current behavioral weight loss programs is to permanently alter eating and exercise habits, attitudes, and cognitive factors. Many books and manuals have been written that describe behavior modification principles and techniques in relation to weight loss (Brownell, 1979; Mahoney & Mahoney, 1976a; Stuart, 1978). Behavior therapy is now typically used as a template for an educational based program that teaches the principles of nutrition, exercise, energy balance, and other factors related to weight loss. Many variables have been identified as being crucial to the success of such programs. These include, but are not limited to, social and peer support, incentives, and exercise. Most programs utilize a target weight loss of about one pound per week and a duration of 8-20 weeks (Buckmaster & Brownell, 1988). In typical programs, the average weight loss of a 16 week program is about 20-25 pounds (Brownell, 1986). Attrition in such programs is of great concern as about 50% of the participants drop out within the first several months (Dishman, 1982). The type and amount of social incentives given to participants may play a key role in promoting the overall success of weight loss programs (Brownell, 1986). Tee Rple 9: Social Support Systems Because of the social nature of eating and the dependence upon others for food purchasing, preparation, and serving, plus the positive reinforcement from those around us, the role of others (especially family members or other significant people) is considered to be a major influence in 15 our eating behaviors (Buckmaster & Brownell, 1988). Social support has been found to be a primary factor in the compliance to exercise programs (Knapp, 1988) and many researchers have found an increase in compliance to weight loss programs when social support systems have been utilized (Buckmaster & Brownell, 1988). . Spousal Influence p: Weight Lpee The influence of family members upon weight loss can have positive as well as negative effects. These negative influences are illustrated in a study conducted by Stuart & Davis (1972). In this investigation, the mealtime interactions of 14 overweight women and their husbands were tape recorded. The women were involved in a weight reduction program, while the husbands were not. Results from these tapes showed: 1. Husbands were 7 times more likely to initiate food- relevant topics of conversation; 2. Husbands were almost four times more likely than their wives to proffer food to the spouse; 3. Wives were slightly over twice as likely as their husbands to reject food offers; and 4. Husbands were over twelve times as likely to offer criticism of their wives' eating behavior than they were to praise it. The authors concluded that the husbands not only failed to help with their wives weight loss, but they actually prevented it (Stuart & Davis, 1972). At least one other study has shown a hinderance effect of spouses on weight loss (O'Neil, 1979). Conversly, other researchers have noted a facilitative influence of spouses when a couple have been trained in behavior modification programs together. Brownell and collegues (1978) used this concept as he devised three 16 treatment groups consisting of: 1. 'Cooperative-spouse-couple training' 2. 'Cooperative-spouse-patient-alone training' where the patient attended meetings alone even though the spouse agreed to enter treatment. 3. 'Non-cooperative-spouse-patient-alone training' whose spouses refused to enter treatment. For each part of the patient's program there was a corresponding assignment for the spouse. Patients were told that a mutual effort was critical to success. All three groups lost weight, but the couples training group lost significantly more weight at six months post-treatment (67% losing over 20 lb. and 22% losing over 40 1b.). The results from this study have been one of the most promising reported in the behavioral literature. Other studies which have also found a beneficial effect of spousal treatments include those by Fremouw and Zitter (1980), Israel and Saccone (1979), and Rosenthal and collegues (1980). Thus behavioral weight loss programs designed to treat an intimate couple, such as husband and wife, are typically (although not always) more effective than individual treatment. Factors Affecting pee Success 9: Socialeupport Systems It appears as though the degree of support given to an individual is a key factor in determining the effectiveness of a weight loss program. Mahoney & Mahoney (1976b) have supported this notion as they found a positive correlation to exist between amount of social support and the amount of weight loss. A social support index was calculated based on attendance in a program and a therapists' report of family cooperation. The correlation between the social support 17 index and weight loss was 0.92 at post-treatment and 0.63 two years later. Thus the amount of support given to a weight loss participant may be a determinant of the amount of weight loss. This phenomenon appears again in a study by Wilson and Brownell (1980), who used family members in the treatment process. This study failed to show a significant difference in weight loss by including a family member in the treatment program. However, it was suggested that the family members played too passive of a role in the program. Other studies confirm the notion that the supporter must play an "active" role. Saccone & Israel (1978) looked at the effect of significant others involved in the weight loss process. A group that had significant others reinforce changes in eating behavior lost significantly more weight than those who attempted to lose weight alone. Specific tasks to aid in weight loss were assigned to the significant other. After eight weeks of treatment, the average weight loss was 13 lb. for the "significant other" participants. Another variable that has been investigated as a significant factor in determining the success of a weight loss program has been the "closeness" of the relationship between the supporter and the patient. Zitter & Fremouw (1978) compared an individual weight loss group with a partner group. The partners were not spouses or significant others, but merely friends who had joined the program together. Both groups made a monetary deposit that was partially returned for both weekly attendance and for weight loss of at least 1 lb/wk. To the authors' surprise, at six month follow-up the individual treatment was significantly 18 more effective. This suggests that treatment with a partner who has little affect on our decision making process seems to be of minimal value in aiding in weight reduction. The authors attributed the poor results to "a mutual reinforcement of inappropriate behaviors" (Zitter & Fremouw, 1978). Therefore, in order for social support to be effective during weight loss there should be a high degree of support given, an "active" role must be played by the supporters, and there should be a close relationship between a partner and the patient. Pee; Support and Weight Lpee Social support from one's peers is generally thought to be an important element in fostering the success of weight loss treatments. Unfortunately, peer support in relation to weight loss has yet to be systematically analyzed. Studies of the effects of peer support groups on various health behaviors typically have been successful (Brownell, 1982; Hertzler & Schulman, 1983; Janis, 1983; Perri, McAdoo & Spevak, 1984). Perri et al. (1984) used a behavior modification scheme which emphasized peer support by the use of a "buddy group" for weight maintenance. Their program included weekly meetings where the buddies monitored each other's weight and provided mutual problem solving as well as positive feeback. Another maintenance group received no such buddies. After 21 months, the buddy group maintained a loss of 10 lbs. (of a 13.5 lb. weight loss), while the control group regained 11.6 lbs. (of a 12.4 lb. loss). Pee; Support egg the Worksite Worksite weight loss programs lend themselves to the incorporation of peer support tactics. Because of the large 19 amount of time spent at work, the stability of the population, and the naturally occurring social networks that develop, the worksite appears to be an ideal environment for weight loss programs. The social bonds that develop in work settings may be the key element to the success of such weight loss programs. ' The success of utilizing peer support at the worksite was shown in a study conducted with employees of The Miriam Hospital in Providence, RI (Abrams & Follick, 1983). The treatment program was a behavior modification template that included the use of another buddy system. This particular system was designed to have participants pair up with fellow employees for social support. Other participants also were given behavioral contract forms that were completed with the two buddies to provide a sense of accountability between the pairs. Another tactic that was used to foster additional peer support was the use of inter-group competitions, which are easily implemented in worksite settings. These strategies were accompanied by a significant weight loss (9.7 lb) during 10 weeks of treatment. Weight Loss Competitions at the Worksite Many companies have implemented inter-group or inter- company weight loss competitions (Abrams & Follick, 1983; Brownell et al., 1984; Reppart & Shaw, 1978; Schumaker et al., 1979; Seidman, Sevelius, & Ewald, 1984; Wear, 1983). Such competitions exploit the natural social factors of work settings, as their use generally has resulted in better than average weight loss and lower attrition rates (Brownell et al., 1984; Seidman et al., 1984). For instance, Brownell and collegues (1984) utilized group competition either 20 within or between companies to foster weight loss and minimize attrition. Each participant paid an initial $5 fee and was assigned to a group. A pool of money from the fees was then awarded to the winning team at the end of 12-15 weeks. All participants lost a significant amount of weight, with a mean weight loss of 12.1 lb. More impressive was the finding that only 1 person of the 213 dropped out, resulting in an attrition rate of less than 1%. Also, almost every overweight person at each worksite participated in the competition. The researchers attributed this success to an increased motivation and social support via the competitive ambience of the worksite environment. According to Stunkard (1989), since this finding of Brownell et a1. (1984), more than 30 weight-loss competitions have been held with results showing a similar pattern of low attrition rates, substantial to moderate weight loss, and increased morale of employees. Tee gple pf Monetary Contracts Using monetary incentives is another method of enhancing motivation that has been utilized successfully in many weight loss programs. Even the mere act of paying for treatment may be enough motivation to enhance success. Stanton (1976) compared patients paying for a hypnotic weight control program with those receiving the same treatment at no cost. After eight weeks of therapy, which consisted of four treatment sessions, those in the fee paying group lost the most amount of weight. Other studies have confirmed this finding (Abrahms & Allen, 1974; Coates, 21 et al., 1982). The most frequent way of applying monetary incentives is in the form of a deposit contract. Deposit contracts are usually constructed to require the participant to either attend a given number of treatment sessions, or lose a stipulated amount of weight, in order to receive reimbursement. A typical contract might state that eight out of ten weekly sessions must be attended before a deposit is refunded. Such contracts have been utilized in a variety of different behavioral health promotion programs, including smoking cessation (Lando, 1977; Stachnik & Stoffelmayer, 1983), weight control (Rozensky & Bellack, 1976), and exercise (Epstein, Wing, Thompson, and Griffin, 1980). Most weight control contracts stipulate that an individual lose a small amount of weight each week. Usually, the amount to be lost is between 0.5-2.0 1b., as this is considered to be an optimal rate of weight loss (American College of Sportsmedicine, 1985). The Effects pf Monetary Contracts eh Weight hpee The use of monetary contracts generally have been successful in facilitating weight loss (Black & Friesen, 1983; Coates et al., 1982; Colvin, Zopf, & Myers, 1983; Dinoff, Rickard, & Colwick, 1972; Harris & Brunner, 1971; Jeffery, Thompson, & Wing, 1978; Jeffery, Gerber, Rosenthal, & Lindquist, 1983; Jeffery, Bjornson-Benson, Kurth, & Kuhn, 1984a; Sperduto et al., 1983; Stalonas et al., 1978). This is illustrated in a study conducted by Black and Friesen (1983) in which subjects were assigned to either a deposit paying or a non-deposit paying weight loss group. A $25 reimbursement was dispersed to participants contingent upon 22 a predetermined goal. The deposit group lost an average of eight times as much weight as the non-deposit group. A review of the literature in this area indicates that there may be a direct relationship between the amount of a monetary deposit and the success of a weight loss program (Coates, 1982; Eufemia & Wesolowski, 1985; Fisher, Lowe, Levenkron, & Newman, 1982; Hagen, Foreyt & Durham, 1976; Jeffery, Thompson, Jarvie, Lahey, & Cureton, 1982). The studies reviewed also indicate, with only one exception (Black and Friesen, 1983), that the use of contracts are highly specific. In other words, if attendance is specified in the contract, then attendance will be achieved and other goals (such as weight loss) may or may not be accomplished. The Effects of Monetary Contracts on Attrition Monetary contracts have been very effective in reducing attrition in weight loss programs (Black and Friesen, 1983; Hagen et al, 1976; Jeffery et al., 1985a; Mavis, 1987; Sperduto et al., 1983; Wilson, 1985). Sperduto et al. (1983) incorporated deposit contracts contingent upon attendance at weight loss meetings. The percentage of clients completing the program was significantly greater for those involved with the deposit contract. Jeffery et al. (1985a) applied a monetary contract system and found a mere 6% attrition rate. In this study participants contracted for payroll reductions whereby the forfeited money could be returned back to them contingent upon successful bi-monthly weight loss. The low attrition rate coincided with the fact that participants also lost a fair amount of weight (12.3 lb). 23 A review by Wilson (1985) reported that the average attrition rate in weight loss programs using monetary contracts was 9.5%, compared with an average attrition rate of 19.3% in behavioral treatments not using monetary contingencies. Eufemia and Wesolowski (1985)-analyzed 97 weight control studies by meta-analysis and found significantly lower attrition rates in those studies that used monetary contracts. In fact, deposits of less than $23.50 resulted in significantly higher attrition (26.11%) than did deposits of more than $23.50 (14.12%). Shepard and Pearlman (1983) reviewed the use of behavioral contracts in the facilitation of many different types of health promoting behaviors. They found that those studies that incorporated such contracts typically produce better results. The Problem 9: Attrition Although monetary contracts have aided in reducing dropout rates, high attrition is still a substantial problem for not only weight loss programs, but medical treatments in general. Dropout rates as high as 80% in various medical treatments are not uncommon (Wilson & Brownell, 1980). Fifty percent of the members of one commercial weight loss program, for example, had dropped out of the program within 6 weeks and 70% within 12 weeks (Volkmar, Stunkard, Woolston, & Bailey, 1981). Similar attrition rates have confirmed the existence of this problem (Ashwell & Garrow, 1985), which appears to be most prevalent at the worksite. 24 Attrition ehg The Worksite Although many worksite weight loss programs have been reported to be highly successful (Brownell et a1, 1984; Epstein & Wing, 1980; Jeffery et al., 1985b; Kneip, Fox, & Frueling, 1985), their number one problem is that of high attrition (Buckmaster & Brownell, 1988). While the use of group competitions and monetary contracts appear to be effective tactics, high attrition rates are still prevalent in worksite based programs (Abrams & Follick, 1983; Fisher et al., 1982; Sangor & Bichanich, 1977). For example, Stunkard & Brownell (1980) employed a variety of different treatments to a worksite setting. While the amount of weight loss was comparable to many commercial weight loss programs (Levitz & Stunkard, 1974), the attrition rate was extremely high, ranging from 31 to 82% across all treatment groups during the four months of the study. In another study of union department store workers in New York City, Brownell et a1. (1985) followed over 170 women throughout a 16-week weight loss program. Only a modest weight loss occurred (<7.7 lb) and attrition rates were very high, between 38 and 58%. Follick, Fowler, and Brown (1984) implemented a monetary contract system in an attempt to curb attrition at the worksite. A $70 deposit, contingent upon attendance and record keeping, was used. Again, there was a high dropout rate (40%) with no difference in weight loss compared to controls. An average attrition of 50% in early worksite programs has been confirmed by several reports (Abrams & Follick, 1983; 25 Brownell, Stunkard, & McKeon, 1985; Fisher et a1, 1982; Sangor & Bichanich, 1977). Brownell et al.(1985) have proposed three possible reasons for the problem of high attrition in worksite based weight loss programs: (a) programs are free, (b) participation is convenient, and (c) there is a social pressure to enroll. Therefore, many persons enroll when they might not otherwise do so. Thus participants at the work-site may start a weight loss program but may lack sufficient motivation to complete it. Recent worksite-based weight loss studies have addressed this problem by utilizing diverse approaches. In addition to utilizing group competitions and deposit contracts, some of the more successful strategies include using lay leaders as opposed to professional leaders (Stunkard & Brownell, 1980), frequent (3-4 times/week) treatment (Brownell et al., 1985), and personal phone reminders (Brownell et al., 1985). All of these strategies have shown to decrease attrition and may be considered appropriate tactics for worksite programs. Attrition ehg Exercise Programs The high attrition rates of weight loss programs are similar to those found in exercise programs (Dishman, 1982). Exercise program adherence has been a consistent problem, especially among the obese (Brownell & Stunkard, 1980; Foss, Lampmann, Watt, and Schteingart, 1975; Foss, Lampmann, and Schteingart, 1976). Dropout rates for exercise programs parallel weight loss programs and may be as high as approximately 70% for obese subjects (Gwinup, 1975) and typically average about 50% within 3 months. The reasons cited by participants for dropping out include monotony 26 (Leon, Conrad, Hunninghake & Sertass, 1979), embarrassment (Brownell & Stunkard, 1980), and a perceived lack of progress (Bjorntorp, 1978). This is unfortunate, as exercise is now considered an essential part of treatment for obesity (Brownell & Stunkard, 1980; Epstein & Wing, 1980; Stern, 1984; Thompson et al., 1982; Zuti & Golding, 1976). Robison et a1. (1991) have recently reported an exercise adherence of about 95% to a university-based exercise program over six months. Group competition, deposit contracts, education, and behavior modification all played key roles in their behavioral program. Data from an unpublished pilot study of a parallel program for weight loss at the same institution shows an adherence rate of about 79% (B.E. Mavis, personal communication, January 24, 1991). Though the two programs used essentially the same tactics, the exercise program included pre and post-program physiological testing, while the weight loss program contained no such protocol. Indeed, the use of periodic physiological testing is now considered to be a fundamental motivational strategy for promoting exercise adherence (Franklin, 1988). However, no scientific studies appear in the literature to support this thinking. It remains to be seen if the establishment of similar testing procedures into the weight loss program would increase the adherence rates accordingly. Knowledge _T Results and Weight Loss Knowledge of results (KR) refers to information provided to an individual after a task that notifies of 27 success in meeting a goal. The importance of KR has long been noted as enhancing the development of motor skills (Newell, 1976). This is accomplished, in part, by KR having a motivational or energizing effect. Early studies (Arps, 1920; Crawly, 1926; Elwell & Grindley, 1938) have found that when KR was not given, subjects tended to become bored at various low skill tasks. Upon presentation of KR, subjects tried harder, practiced longer after KR was withdrawn, and generally were more interested in the task. Indeed, KR has been found to improve strength, endurance, and reaction time (Newell, 1976). KR may have an important function in the goal setting process (Locke, Cartledge & Koeppel, 1968), which could account for some of the motivational effects. Knowledge of results has been applied to weight loss treatment primarily by having the client perform various self-monitoring techniques. Typically this involves recording either one's daily weight, waist girth, or the amount of food consumed. Investigators have shown that the simple act of self-recording a behavior can actually change that behavior, whether it be smoking, overeating, studying, nail biting, etc. (Kazdin, 1989). Numerous researchers have applied some form of self-monitoring behavior as part of their weight loss treatments (Harris, 1969; Harris & Bruner, 1971; Penick, Filion, Fox & Stunkard, 1971; Stuart, 1967; Stuart & Davis, 1972), with varying degrees of success. Although the reasons that self-monitoring frequently alters behavior are not clear, this feedback most likely has the same motivational effects of KR as previously mentioned (Nelson & Hayes, 1981). 28 To date, the effects of feedback obtained from monitoring one's body composition (the amount as well as anatomical location of fat loss) during weight loss treatments have yet to be studied. However, at least one expert considers periodic physiological testing to be an important motivational strategy for increasing exercise adherence (Franklin, 1988). As previously mentioned, Michigan State University's Worksite Wellness Program recently reported an exercise adherence rate of over 95% (Robison et al., 1991). This exercise program involved physiological testing, while a parallel program for weight loss that did not administer physiological testing had only a 79% adherence rate (B.E. Mavis, personal communication, January 24, 1991). The subject's knowledge of results from the testing may be a critical factor in the exercise program's greater adherence rate. Physiological Aspects pg Weight Thee When studying the composition of the human body, tissue mass is divided into fat and fat-free components. Fat is mostly in the form of triglycerides, and is found mainly in adipose tissue. Fat-free mass (FFM) is devoid of all fat and is therefore composed entirely of water (73%), protein (20%), mineral (8%) and glycogen (1—2%) (Garrow, 1974). Lean Body Mass (LBM) is a frequently used term that pertains to the FFM plus essential fat mass. While the majority of protein and all of the glycogen in FFM are found within the cells, water is found in both the intracellular and extracellular spaces (Moore, Olesen, & McMurrey, 1963). 29 Weight Loss and Body Composition During the early phase of strict caloric restriction, there is a significant amount of water loss. This can be attributed to the oxidation of glycogen (Cahill, 1976), as about 3 grams of water is stored with each gram of glycogen. This has led to the misconstrued promise of many commercial weight control programs for "quick" weight loss. After this initial period, the two primary sources of energy for the body are triglycerides and amino acids. Hence, free fatty acids stored in adipose tissue and amino acids from skeletal muscle will be utitlized to produce ATP. The rate of this oxidation and the proportion in which these two substances are utilized is controlled by many different factors. Generally, the rate of weight loss is a function of the degree of the energy deficiency. Mathematical analysis shows that the rate of weight loss is proportional to the amount of body weight itself. Since body weight will be decreasing with weight loss, the rate of loss therefore will diminish with time (Forbes, 1970). The reasoning for this has been linked to the decrease in LBM that occurs with dieting (Grande & Keys, 1980). Hence, there is a decreased amount of "metabolically active" tissues requiring energy to survive. It seems that whenever significant amounts of body weight are lost, both LBM and fat contribute to the weight loss. Thus, during weight loss LBM and fat should not be thought of as two mutually exclusive entities (Forbes, 1987). The amount of LBM that is used for energy needs is contingent upon two factors: (a) an individual's initial fat 30 content and (b) the magnitude of the energy deficiency. It has been shown that thin subjects lose twice as much body nitrogen per unit of weight loss as obese individuals (Loucks, Horvath & Freedson, 1984). This translates into a reduction in LBM for thin persons. Also, thin individuals consuming diets of 1400-1900 Calories have a greater loss of LBM than obese individuals (Keys et al., 1950; Young & DeGiacomo, 1965; Young, Scanlong, & In, 1971). It therefore appears that obese individuals burn fat to preferentially conserve lean tissue. The severity of the energy deficit also dictates the type of tissue that will be oxidized to meet energy demands. The ratio of LBM change per body weight change is directly related to the energy deficit (Forbes, 1988). The greater the energy deficiency, the more LBM lost. In fact, even a small reduction of energy intake leads to some protein catabolism (Young et al., 1984). This problem can be frequently off-set by instituting an exercise program, which tends to reduce the amount of lean tissue lost (Babirak, Dowell & Oscai, 1974; Keys et al., 1950; Larsson, 1967; Zuti & Golding, 1976). Large energy deficits are frequently associated with many popular diets. In these cases, an individual tends to lose even larger amounts of lean tissue. This may cause serious health problems. Such drastic weight loss techniques are seldom successful (Innes, Campbell, Campbell, Needle & Munroe, 1974), and are now denounced by health professionals (American College of Sports Medicine, 1976 & 1985). Therefore weight loss should be a slow, gradual process to ensure that fat is the primary tissue being lost. Accepted recommendations call for a maximum of 1-2 pounds of 31 weight loss per week in moderately obese individuals (American College of Sports Medicine, 1985; Mayer, 1980). When a loss of body fat does occur, fatty acids are mobilized from fat depots throughout the body to provide energy. Usually, the areas of greatest fat concentration supply the most energy (McArdle, Katch & Katch, 1986). Also, fatty acids are not preferentially oxidized from fat pad directly over working muscle (Gwinup, Chevlam & Steinberg, 1971; Krotkiewski, Mandroukas & Sjostron, 1979). Therefore, contrary to popular belief, localized fat loss is not possible. Indices p: hpgy Composition This section provides a review of the methods for determining body composition which were used in the present investigation. This included hydrostatic weighing, skinfolds, body mass index, and circumference measurements. Hydrostatic Weighing Since the density of fat is much less than that of muscle and bone tissue or water, body density can be calculated from whole body submersion. Measurement of specific gravity is perhaps one of the most accurate methods for estimating fat content of the body (Lohman, 1981). Specific gravity can be determined by applying Archimedes' principle, which states that an object immersed in water loses an amount of weight equal to the weight of the volume of water that is displaced (McArdle et al., 1986). Body density can then be calculated by using the simple formula of: 32 Weight (airl Body Density = (Weight air - Weight water) - Residual Vol. Density of Water (in lungs) After measuring body density, percent body fat is estimated from the Siri (1961) or Brozek (Brozek, Anderson & Keys, 1963) equation. These equations partition the body into lean and fat tissues, and were derived from using known constants for the densities of human tissues. Air in the subject's lungs must be taken into consideration when obtaining an underwater weight as this will increase buoyancy. Therefore the amount of air that cannot be expired upon maximal exhalation, or residual volume, must be accounted for. Methods used to measure residual volume include oxygen rebreathing, hydrogen rebreathing, nitrogen washOut, and helium dilution (Rahn, Fenn & Otis, 1946). The hydrostatic weighing technique is considered to be the "gold standard" of the non-invasive methods of body composition analysis (Katch & Katch, 1980). Yet any method which predicts % body fat from body density is subject to errors such as the individual variability of bone mineral and-muscle density, as well as total body water (Wilmore, 1983). Such an intrinsic error is thought to be about t 2.5% (Lohman, 1985). Skinfolds The amount of subcutaneous fat is proportional to body density (Pascale, 1956). Therefore, measurement of subcutaneous fat gives a relative index of total body fat (Brozek & Keys, 1951). This subcutaneous fat layer varies among sites on the body, between individuals, and between 33 the same individual at different ages and points in time. Therefore, skinfolds should be measured at various anatomical locations. Skinfold measurements may be most useful, however, for following body fat changes in an individual over time. The validity of the skinfold measurement technique to predict body composition lies in the proper use of "population specific" regression equations. Such equations are derived while using a sample of subjects with a certain set of characteristics, such as age, sex, state of training, and degree of fatness. Therefore, individuals being assessed by skinfolds must conform to these characteristics from which the equation was dervived (McArdle, et al., 1986). Probably the greatest threat to validity is that of the experience and technique of the person performing the measurements. When population specific equations are improperly applied or an inexperienced technician performs the measurements, the error in prediciting body fat could be as much as plus or minus 200% (Katch & Katch, 1980). Other extraneous factors can also reduce the precision of skinfold measurements. Extreme heat, for example, may lead to either peripheral vasodilation or an accumulation of extracellular fluid, both of which could induce an overestimate of skinfold thickness (Schemmel, 1980). Physiological altherations such as dehydration, edema, and muscle atrophy have all been known to impede accurate skinfold measurements (Schemmel, 1980). Generally, skinfold equations which predict densitometrically determined percent fat typically have a standard error of between four and six percent 34 (Segal, Gutin & Presta, 1985). WWW Body mass index (BMI) was originally developed to provide a classification of overweight that could be easily used in a clinical situation. BMI, also known as the Quetelet Index, was originiated by Quetelet, a 19th century Belgian astronomer (Garrow, 1981). The calculation is based on two measurements: height without shoes and weight with minimal clothing. The BMI is calculated by dividing the weight (kg) into the square of the height (m). The classifications for degree of obesity are based on mortality ratios derived from life insurance tables. The classifications are as follows, with Grade 0 considered to be at ideal weight (Garrow, 1981): Grade - III: W/H2 > 40 II: W/H2 30 to 40 I: W/H2 25 to 29.9 o: W/H2 20 to 24.9 Circumference Measurements Measuring the circumferences of various body sites has recently been found be an accurate method of estimating body composition. McArdle, Katch & Katch (1991) have developed prediction equations based upon three circumference sites. The error associated with their technique was i 2.5 to 4.0%., which is smaller than that of some skinfold estimations. The use of circumference measurements also may allow an individual to see specific sites of weight loss, 35 which is not possible with hydrostatic weighing or even skinfold measurements. In this way, an additional reinforcement to continue to lose weight may be provided. Generally, hydrostatic weighing is accepted as the most accurate non-inavasive method of determining body composition. It is considered the gold standard from which anthropometric estimations (e.g., skinfolds and circumference measurements) are derived. However, using such anthropometric measurements in conjunction with hydrostatic weighing are important if one wishes to know the distribution of body fat and the location of fat loss along with percent body fat. Summar Before behavior modification techniques were initiated in the treatment of obesity, weight loss programs were generally unsuccessful as they suffered from high attrition rates and very little weight loss. The use of behavioral techniques such as self-monitoring, stimulus control, social support, exercise, competition, and monetary contracts has led to substantial improvements of weight loss programs. Current behavior modification programs have been found to result in a 1.0 to 1.5 pound loss per week during treatment. Most successful programs typically see a weight loss of about 20 pounds in 16 weeks of treatment. Unfortunately, acceptable attrition rates in today's programs are still of concern as about 50% of participants drop out within several months. This problem is most prevalent in worksite weight loss programs. The use of inter-group competitions (particularly at the worksite) have 36 shown to be effective in combatting high attrition. One study found an attrition rate of less than 1% when inter- company competitions were held at the worksite (Brownell et al., 1984) Monetary contracts have also shown to be effective in combatting attrition, as well as promoting weight loss. The success of such contracts is specific to the goal which has been stipulated in the contract. If attendance to program meetings is stipulated, then successful attendance is most likely to be obtained, and weight loss goals may or may not be accomplished. Also, the greater the amount of money contracted, the greater probability of obtaining one's goals. The addition of social support to weight loss treatments also appears to affect both weight loss and attrition. Support from spouses and peers seem to be most effective when a high degree of support is given by an individual with much influence over our decision making process. Ideally, the supporter should play an "active" role in the supporting process. Much of the success of behavioral weight loss programs can be credited to the use of self-monitoring techniques. The feedback of performing such tasks can have a substantial motivating effect. Enhancement of weight loss efforts in response to receiving feedback (knowledge of results) of body composition assessment has yet to be investigated, and is the focus of the current research. CHAPTER III RESEARCH METHODS This study was designed to test the following hypotheses: 1. Weight loss adherence rates would be significantly higher in a group that has body composition assessment in addition to participation in a behavioral weight loss program, compared to those participating in a behavioral weight loss program without body composition assessment. 2. Body circumference measurements, skinfold measurements, and percent body fat would be significantly lower after a six month behavioral based worksite weight loss program. Research Design Subjects who underwent a six month weight loss program at worksite A on the Michigan State University campus, plus received body composition testing and the subsequent knowledge of results, were classified as subjects in the experimental group (EXP). The EXP subjects received initial, three month (mid), and six month (post) body composition assessments which included body weight, skinfold thicknesses at six sites, hydrodensitometry, and circumference measurements. Control subjects (CON), who had similar characteristics (age, sex, employment level status) 37 38 compared to EXP, participated in a similar behavior modification package but did not undergo any body composition testing. The research design of this study was quasi- experimental. Worksites A and B were not randomly assigned to the EXP and CON conditions, nor were the participants at each site. In addition, the weight loss programs at the two site were run approximately two and a half years apart and utilized different program leaders. Subjects Potential subjects for the study were recruited via a promotional health fair at their worksite as well as by informational flyers posted at their respective worksite buildings. Approval for this study was obtained from the University Committee on Research Involving Human Subjects (UCRIHS). All research procedures, along with the risks and benefits of the study, were carefully explained to EXP subjects in an initial orientation meeting for the weight loss program. At this meeting subjects volunteered to participate in the study and were then asked to provide written informed consent (Appendix A). Sixteen, sedentary women were recruited from worksite unit A on the Michigan State University campus to participate in the EXP group weight loss program. Of these individuals, 13 volunteered to serve as EXP subjects. Due to attrition throughout the course of the study, 10 subjects completed all testing procedures and were included in the data analyses as EXP subjects from Worksite A. The remaining three individuals participated in the Worksite A 39 program without becoming EXP subjects. The subjects were 25-53 years of age and free of any medical conditions that would contraindicate moderate weight loss over a program duration of six months. One subject in the EXP group was an insulin-dependent diabetic, and received insulin injections routinely. Ten females participated in the program at Worksite B. These subjects were 28-60 years of age and were included in the data analysis to serve as the CON group. Weight Loss Progpam The subjects at both worksites (A & B) underwent a six month behavior modification weight loss program that incorporated monetary contracts, group competition, and peer support as motivational incentives. This incentive scheme has been utilized previously by Stachnik & Stoffelmayer (1983) for smoking cessation, Mavis (1987) for weight loss, and both Robison et al. (1991) and Stoffelmayer et al., (1991) for exercise. The program consisted of a weekly meeting where the participants were weighed, contracts were verified, and an educational lecture was presented. This educational component consisted of lectures on energy balance, caloric expenditure, dietary record keeping, and other nutritional topics relative to weight loss. After the first 10 weeks of the program these meetings became semi-monthly, which led to a total of 17 meetings throughout the six months. At the EXP weight loss program, the principle investigator served as one of two group leaders for these meetings. A staff member of the MSU Department of Psychiatry led the CON 40 program. Both of these group leaders were under the direct supervision of the director of the MSU Worksite Wellness Program. To enhance motivation, participants were divided into teams and a monetary deposit contract system was implemented. Participants chose, according to personal preference, on which team they wished to compete. There were four teams in the program at Worksite A (EXP) and three teams at Worksite B (CON). The monetary deposit contract, signed by each individual participant, was a written contractual agreement that stipulated a weight loss of between 0.5 and 1.5 lbs/week over the six month period. The specific amount of weekly weight loss was determined mutually by the participant and the program leader according to the specific needs of the participant. The EXP group contracted to lose an average of 0.85 t 0.11 lbs. per week, while the CON group contracted for a mean weight loss of 0.90 i 0.16 lbs. per week. These values were not significantly different, as analyzed by an independent t- test. Adherence to the contract was determined by "weighing- in" at the weekly meetings. If a participant did not lose the contracted amount of weight, they were considered to be unsuccessful in adhering to the contract. Each subject's adherence was calculated by dividing the number of weeks successfully adhering to the weekly contract by the total number of weeks of the weight loss program. To fulfill this contractual agreement, the participant was required to place $40 on deposit to support their contract. This in effect "placed a bet on themselves" to 41 successfully adhere to the written contract. The $40 deposit was placed in escrow until the completion of the six month program. Subjects who failed to adhere to this contract forfeited one half of his/her remaining deposit money. Thus, $20 was forfeited for the first failure, $10 for the second failure and so on. At each failure to adhere to the contract, the forfeited money was placed into a common pool of money. Each week, the money in this pool was divided equally among those teams whose members had all successfully adhered to their weekly contract. Any team in which one or more members did not adhere to their weekly contracts was ineligible for the sharing of money in the pool. At the last program session, the money received through forfeiture by individuals during the course of the program was distributed as cash to participants. Assessment of Body Composition A series of body composition measurements were determined initially, at three months, and after the six month intervention in EXP subjects at Worksite A, as this was hypothesized to enhance adherence to the program. All assessments were made at the Center for the Study of Human Performance (CSHP) in the Department of Physical Education and Exercise Science. All tests were administered and all data was collected by a single investigator throughout the study. Data was recorded by a trained laboratory assistant. Because of the possible cyclical variation in body composition due to fluid changes during the menstrual cycle, all subjects were tested at the same point in their 42 reproductive cycle at all three time points. The typical length of menstrual cycle, along with the starting and ending day of the month was ascertained via a questionnaire. The methods used to assess body composition in this study include: (a) body mass index, (b) body circumferences, (c) skin folds, and (d) hydrostatic weighing. The rationale for using four separate methods lies in the fact that subjects were to be provided with results of not only hey mpeh fat loss was occurring (via hydrostatic weighing), but phepe the fat loss was occurring (via skinfolds and circumferences). Body Mass Index was utilized for comparison purposes. WWW Body mass index, a gross measurement of leanness/fatness, was calculated using the simple formula of weight (kg)/height (m)2. Historically, BMI has been used to classify the degree of overweight and is based upon mortality statistics. Subjects were weighed on a balance beam scale (Fairbanks, Inc.) to the nearest 0.1 kg and height was recorded on a stadiometer (Holtain Ltd., England) to the nearest cm. hpgy circumferences Measuring alterations in body circumferences during weight loss can provide a valuable supplement to % body fat measurements. Individuals are given a vivid indication as to the specific sites of subcutaneous fat loss, which may be helpful in offering positive reinforcement to continue to lose weight. Circumference measurements alone can be used to determine body composition, as equations for predicting body fat have recently been developed. One set of equations 43 has shown to have an error of only about i 2.5 to 4.0 % when compared with hydrostatic weighing results (McArdle, Katch, & Katch, 1991). The purpose of circumference measurements in this study, however, was not to predict body composition, but to provide additional feedback of the distribution of fat loss. . Circumference measurements were performed at the abdomen, buttocks, and calf. The specifics of site location and measurement technique were adapted from Callaway and colleagues (1988), and can be found in Appendix B. All measurements were made using a flexible steel tape measure (Lufkin, USA). The tape was held at the point of maximum circumference but without compressing subcutaneous adipose tissue. All measurements were recorded to the nearest 0.1 cm. The abdominal and buttocks circumferences were measured at the level of greatest protrusion in the horizontal plane. Similarly, the calf circumference was measured at the point of maximum circumference perpendicular to the long axis of the tibia. Three non-consecutive trials were used for each site. The circumference measurement recorded was the mean of the two closest measurements. An assistant served as a data recorder in an attempt to restrict tester bias in recording of the results. Skinfolds A pilot study was performed to assess the reliability of the technique of the principle investigator before any skinfold measurements were initiated in the present study. Repeat skinfold measurements were performed on 10 subjects at six sites. These subjects were non-obese student volunteers from Michigan State University, and were not 44 associated with the study. Correlation coefficients (r) for each skinfold site were calculated to describe the relationship between skinfolds measured one week apart. In addition, validity of the skinfold measurements was checked by correlating the results with a highly proficient technician. The reliability (r = 0.98) and validity correlations (r = 0.99) were both statistically significant (p < 0.001). This provided a general indication of the reliability and accuracy of the principle investigator's skinfold measurement technique. Data from this pilot study are provided in Appendix C. Skinfold thickness measurements for estimating body fat were calculated using a specific population regression equation as presented by Durnin and Rahaman (1967). This equation was found to have a correlation coefficient of - 0.778 (p < 0.001) for total skinfold thickness and body density (as assessed by hydrostatic weighing) in adult women. (Durnin & Rahaman, 1967). The Lange skinfold caliper, which exerts a constant tension of 10 g/mmz, was used for all tests. The general procedure followed for obtaining these measurements was to grasp a fold of skin and subcutaneous tissue between the thumb and forefinger of the left hand and lift it firmly away from the underlying muscle. The caliper was applied to the fold by slowly allowing the jaws of the caliper to come together on either side of the fold at a point 1 cm below and perpendicular to the fingers. Pressure on the fold at the point measured was exerted by the caliper and not the fingers. A reading was then taken from the caliper to the nearest 0.5 millimeter after 1-2 seconds had elapsed. At Ii 45 least two measurements were taken at each site. If these two measurements differed by more than two mm, a third measurement was taken to assure accuracy. The skinfold measurement recorded was the mean of the two closest measurements. The six sites, measured on the right side of the body, were: 1. Triceps: Vertical fold taken on the posterior midline of the upper arm, halfway between the acromion and olecrannon processes. 2. Biceps: Over the midpoint of the belly of the muscle with forearm supinated. 3. Subscapular: A diagonal fold just below the tip of the inferior angle of the scapula at a 45° angle to vertical. 4. Suprailiac: A diagonal fold just above the iliac crest, in the mid-axillary line. 5. Umbilical: A vertical fold taken at a lateral distance of 2 cm from the unblilicus. 6. Front Thigh: A vertical fold on the anterior aspect of the thigh midway between the head of the femur and Eggximal border of the patella. The sum total (mm) of the first four sites was used in the adult women regression equation to estimate body fat. These equations are provided in appendix D. Site fives and six were used to provide subjects with feedback concerning fat loss in these locations. Hydrostatic weighing The hydrostatic weighing procedure was used to determine body density. Since lean body tissue has a density of 1.100 g/ml, and adipose tissue has a density of .900 g/ml, fat will "float" in water and cause an individual to weigh less than on land. The difference between body weight measured in air and the underwater weight gives body 46 density by the following equation (Buskirk, 1961): Body Density = Weight (air) Weight (air) - Weight (water) - Residual Vol Density (water) The specific density formula used in this study is provided in Appendix E. Once body density was determined, % body fat was calculated by using the Siri equation as follows (Siri, 1961): % Body Fat = 495 _ 450 Body Density The underwater weighing protocol used in this study has been meticulously described by Zelasko (1984). Briefly, body density was measured in a seated position on a platform beneath the surface of the water. This platform was attached to a strain gauge (Model SR-4 Load Cell Type UI-B, Malwin-Lima Hamilton Corp) for the determination of body weight underwater. A signal from the strain gauge was sent to a graphic recorder (Model 2115M, Allen Datagraph Corp.) through the use of a Wheatstone Bridge. The range of the recorder is 0 to 12.5 pounds, and the weighing system was calibrated by placing a 9.95 pound weight onto the strain gauge and then manually adjusting the graphic recorder to reflect this weight. Since air in an individual's lungs during hydrostatic weighing will increase buoyancy and affect the determination of body density, residual volume must be measured. While various methods of measuring residual lung volume have been established, at the CSHP residual volume is routinely 47 measured underwater by a modified version of the closed circuit, nitrogen dilution method (Rahn et al., 1946). Briefly, a subject breathes in a gas mixture (approximately 95% 02 and 5% C02) from a 3 liter rebreathing bag to "washout" as much nitrogen from the lungs as possible. By comparing the difference in the amount of nitrogen in the bag before and after the rebreathing procedure, a precise measurement of residual lung volume can be obtained. A four breath rebreathing maneuver was used to ensure adequate mixing between alveolar gas and the gas mixture in the bag. The formula used in the calculation of residual volume is provided in Appendix E. The nitrogen content of this rebreathing bag system was continuously monitored by a MedScience 505 Nitralizer. The nitralizer was calibrated every three to four subjects by manually adjusting the instrument to read the ambient nitrogen content. Ambient nitrogen was calculated from barometric pressure, room air temperature, and relative humidity. A diagram of underwater weighing system is shown in Appendix F. hehe Collection Schedule Subjects were asked to report to the CSHP at least 3-4 hours post-prandial on the day of testing. The time of day that subjects were scheduled for testing varied according to subject availability at each of the three measuring times. Once at the CSHP, subjects changed into swimming attire, voided the bladder and bowel, and then were weighed on the balance scale. At the initial testing period, height was assessed. Following this, skinfolds and circumferences were 48 measured and recorded. A familiarization session to provide an overview of the underwater weighing procedure was given to the subject before entering the tank. At least one practice trial of the procedure was then allowed so that the subject became comfortable with all aspects of the weighing protocol. Two to three actual underwater weighing trials were performed for each subject. If the first two density determinations differed by more than .001 g/ml., a third trial was performed. The mean of these trials was then recorded as the body density. Body density and % body fat calculations were performed as previously described (Appendix E) using a Hewlett-Packard 67 programmable calculator. The data collection sheets for all testing procedures are given in Appendix G. After all necessary calculations were performed, the results were recorded onto a form which was distributed to EXP subjects either at the next weekly meeting, or by mail if the participant did not the following meeting. This form provided confidential feedback and is provided in Appendix H. Subjects were provided with a brief individual interpretation of these results (i.e., norm ranges of % body fat, location of fat loss, etc.) at the next meeting, or a written interpretation was provided the results were mailed. For the three and six month testing sessions, subjects were provided with copies of the previous test period results so comparisons could be made. 49 Statistical Analyses The study was designed to measure body composition prior to the weight loss program, at the program's midpoint (three months), and at the termination of the six month program. The data were analyzed by a repeated-measures one- way analysis of variance (ANOVA) for the following dependent variables: (a) skinfold thickness, (b) abdomen, buttocks, and calf circumference, (c) body weight, (d) lean body mass (e) hydrostatic weighing % body fat, and (f) skinfold % body fat. To determine the affect of body composition testing on adherence to weekly contracts, an independent t-test was used to compare differences in adherence rates between EXP and CON groups. The independent t-test was also used to distinguish EXP and CON differences in total weight loss and subject characteristics. A 0.05 level of significance was set for all tests. Data are reported as means i Standard Error (SE). Raw data is provided in Appendix I and analysis of variance tables are given in Appendix J. CHAPTER IV RESULTS AND DISCUSSION The purpose of this study was to examine the effects of body composition testing on adherence to a six month behavioral weight loss program. Subject Characteristics The descriptive characteristics of the female subjects are presented in Table 4.1. The EXP group had a mean age of 42.3 f 3.2 (range 25-53) years, initial mean body weight was 77.9 i 3.9 (range 50.2-92.2) kg and height was 165.1 f 2.5 (range 151.6-181.5) cm. The mean BMI was 28.5 i 0.4 (range 21.8-34.9), indicating Grade 1 level of obesity. BMI can be categorized by four grades of obesity, with grade 0 corresponding to a BMI of 20 to 24.9 and considered as "normal". Grade 1, the first level of obesity, occurs at a BMI of between 25 and 30, and is associated with a small increase in mortality (Garrow, 1981). There were no significant differences between EXP and CON characteristics, except for height (EXP = 165.1 i 2.5 cm; CON = 162.8 i 2.2 cm), with the EXP subjects being slightly taller (p < .05). 50 51 TABLE 4.1 Subject Characteristics Group Age Height Weight BMI 2 (yr) (cm) (kg) (W/h ) EXP 42.3 165.1* 77.9 28.5 (N=10) i 3.2 + 2.5 i 3.9 i 0.4 CON 48.0 162.8 77.3 29.3 (N=10) i 2.8 + 2.2 i 3.3 i 1.4 x i SE p < 0.05 vs. CON Skinfold and Body Circumference Measurements Data on skinfold thickness measurements are presented for the EXP subjects in Table 4.2. Repeated measures ANOVA for each site revealed that no significant changes occurred in skinfold thicknesses measured at six specific sites over the duration of the study. For instance, the average diameter of the tricep skinfold was 28 i 2 mm initially, 30 i 1 mm at three months, and 28 i 2 mm at six months. The sum of the six skinfolds (235 + 8 mm initially, 258 i 9 at three months, and 239 t 9 at six months) was also not significantly different at any of the three points in time. 52 TABLE 4.2 Effects of Weight Loss Program on Average Skinfold Thickness For EXP Group Site Initial Three Month Six Month Tricep 28 i 2 30 1 1 28 I 2 Bicep 18 i 2 21 j 1 17 I 2 Subscapular 21 i 2 21 t 2 20 j 2 Suprailliac 22 i 2 24 i 3 22 i 2 Umbilical 22 i 3 25 t 3 23 t 3 Thigh 31 t 1 34 i 2 33 t 2 Sum Of 6 235 + 8 258 + 9 239 i 9 Sites ' ' Values are x 1 SE in mm N = 10 The data for three body circumferences are presented in Table 4.3. The mean abdominal circumference measurements were 85.1 i 3.1 cm, 85.2 i 3.3 cm and 84.4 i 3.4 cm at the respective initial, three month, and six month time points. The mean buttocks circumferences were 110.4 i 2.6 cm, 109.1 3 2.9 cm, and 109.3 f 3.0 cm at each time point. The mean values of the third site, the calf, were 40.0 i 1.5 cm, 39.6 i 1.4 cm, and 39.4 i 1.4 cm at the three time points. As was the case with the skinfold measurements, six months of participation in the behavioral weight loss program did not 53 significantly alter this index of localized subcutaneous fat at any of the three sites assessed. TABLE 4.3 Effects of Weight Loss Program on Average circumference Measurements at Three Sites for EXP Group Site Initial Three Month Six Month Abdominal 85.5 i 3.1 85.2 i 3.3 84.5 i 3.4 Buttocks 110.4 f 2.6 109.1 f 2.9 109.3 f 3.0 Calf 40.0 i 1.5 39.6 I 1.4 39.4 t 1.4 Values are x t SE in cm N = 10 Body Composition The effects of the behavioral weight loss program on % body fat as determined by hydrostatic weighing and skinfold thickness, as well as lean body mass (LBM) determined by hydrostatic weighing, for EXP subjects are presented in Table 4.4. These data of body composition revealed that there was no significant alteration of either % body fat or LBM at any of the three time points. The mean % body fat as assessed by hydrostatic weighing of the EXP subjects, 42.6 i 2.4%, categorizes them as obese, as a value over 30% body fat for women is typically cited as the criteria for obesity (McArdle, Katch & Katch, 1986). The differences found between the hydrostatic weighing and skinfold estimations of 54 % body fat can be explained by the inherent sources of variation associated with skinfold estimations. In this case, the differences may be due to the large amount of subcutaneous fat of EXP subjects, which can impede accurate skinfold estimations (McArdle et al., 1986).‘ Typically, % body fat from skinfolds and hydrostatic weighing vary on the order of 3-5 %. Interestingly, the correlations between the H20 %BF and that of the SF %BF increased at each testing period, and was significant at the six month period (r = 0.72, p < 0.05). TABLE 4.4 Effects of Weight Loss Program on Body Weight, % Body Fat, and Lean Body Mass for EXP Group Initial Three Month Six Month Hydrostatic Weighing 42.6 t 2.4 40.5 i 2.7 39.6 i 2.8 % Body Fat Skinfold % Body Fat 34.8 t 1.8 36.9 i 1.2 35.3 i 1.4 Lean Body Mass 45.2 i 2.3 46.3 i 2.3 46.3 i 2.5 (R?) Values are expressed as mean t SE N = 10 Weight Loss The EXP group's mean body weight at the initial, three month, and six month time periods were 77.9 t 3.9, 77.1 t 3.9, and 76.2 i 3.8, respectively. The CON group's mean body 55 weights at the same time points were 77.3 f 3.3, 73.3 i 3.6, and 70.9 i 3.8. These values are presented in Table 4.5. One way repeated measures ANOVA's showed no significant changes in body weight at any of the three time points for either the EXP or CON group. The mean weight loss over the six months for both the EXP and CON groups are presented in Figure 4.1. The EXP group's weight loss was 1.8 i 1.4 kg, or about 3.7 lbs. Although the one way repeated measures ANOVA revealed that this approximate 2.2% reduction in body weight was not statistically significant, an independent t-test revealed this to be significantly less (p < 0.05) than the CON group's 8.3% reduction of 6.3 i 1.4 kg, or about 14 lbs. TABLE 4.5 Effect of Weight Loss Program on Body Weight for EXP and CON Groups Initial Three Month Six Month EXP Group Body Weight 77.9 i 3.9 77.1 i 3.9 76.2 i 3.8 (kg) CON Group 77.3 t 3.3 73.3 + 3.6 70.9 + 3.8 Body Weight ' ' (k9) x t SE N = 10 for both groups 56 FIGURE 4.1 Weight Loss Over Six Months in EXP and CON Groups 10 1k 1_ 5 _"_ WT LOSS —— (kg) 1 EXP con N = 10 N = 10 * p < 0.05 vs. EXP Values are expressed as means. 57 W Average group % adherence to weekly contracts are presented in Figure 4.2. A subject was successful in adhering to the contract if they lost the amount of weight which was stipulated in their contract. An individual's adherence rate was calculated by dividing the number of weeks a subject successfully adhered to their contract by the total number of weeks in the weight loss program. The group adherence rate was the average of each subject's adherence rate within a particular group. The EXP group had an adherence rate of 52.6 i 6.0 (range 31-81) %. The CON group's adherence was 81.6 i 4.3% (range 58-100) %, and was significantly greater than EXP (p < 0.01). 58 FIGURE 4.2 Contract Adherence to the six Month Program for EXP and COM Groups 100 —— i: _T_ 50 —-— Adherence (’6) 0 EXP CON n = 10 n = 10 * p < 0.01 vs EXP Values are expressed as means. 59 The intercorrelations between the program measures of adherence, attendance, and weight loss, and also these measures with that of the body composition measure of percent fat loss for the EXP group are given in Table 4.5. The Pearson product-moment correlation coefficient revealed a significant correlation (r = 0.65, p < 0.05) between percent fat loss and weight loss. Similarly, the correlations between weight loss and adherence (r = 0.67, p < .05) and attendance and adherence (r = 0.58) were also significant (p < 0.05) for the EXP group. The correlation between fat loss and adherence (r = 0.48), fat loss and attendance (r = 0.04), and weight loss and attendance (r = 0.34) did not reach significance (p > 0.05). The correlation between weight loss and adherence for the CON group is also shown in Table 4.5. This correlation (r = 0.60) did not reach significance at an alpha level of 0.05. CON attendance data were not available. 60 TABLE 4.5 Correlation Coefficients of Body Composition Measures and Program.Measures for EXP Group EXP Percent Body Fat LossA & Weight Loss (kg) r = 0.65* EXP Percent Body Fat Loss- & Adherence (%) r = 0.48 EXP Percent Body Fat Loss‘ & Attendance (%) r = 0.04 EXP Weight Loss (kg) 8 Attendance (%) r = 0.34 EXP Attendance (%) & Adherence (%) r = 0.58 EXP Weight Loss (kg) & Adherence (%) r = 0.67* CON Weight Loss (kg) & Adherence (%) r = 0.60 f Correlation is significant at p < 0.05 Assessed by hydrostatic weighing n = 10 61 Discussion Analysis of the body composition data indicate that the EXP weight loss program, with an adherence rate of only about 53%, did not elicit significant changes in body weight, skinfold thickness, body circumference, or percent body fat in EXP subjects. It is clear from these data that the EXP group's weight loss program was unsuccessful, as neither body weight or % body fat were significantly altered. Furthermore, the adherence to weekly contracts and amount of weight lost were significantly greater in CON, which received no body composition assessments. Repeated measures ANOVA's revealed that neither the EXP or CON groups lost a significant amount of weight. However, the CON group's mean weight loss (6.3 + 1.4 kg) was significantly greater than that of the EXP group (1.8 + 1.4 kg). The CON group's weight loss may have not reached statistical significance because of a large variability in body weight. In fact, both the CON and EXP groups had a standard error in body weight of 3.8 kg. Wing & Jeffery (1984) have noted that behavioral weight loss treatments generally have a high degree of variability in treatment outcome. To account for this finding, they suggest that behavioral weight loss studies increase their sample size to avoid making a Type II error, concluding a difference does not exist when in fact one does. If the CON group in the present investigation had a greater sample size, a significant ANOVA of body weight may have been obtained. A reduction in sample size of the EXP group was experienced throughout the course of this study. Although 62 thirteen individuals originally volunteered to participate as EXP subjects at the first program meeting, this number diminished throughout the study such that only 10 subjects had all initial, mid, and post program body composition assessments performed. Analysis of the non-participant data (found in Appendix I) using independent t-tests revealed that there were no significant differences (p>.05) in age, attendance at weekly meetings, adherence, or weight loss between EXP subjects and those who dropped out of the EXP group yet still participated the weight loss program at Worksite A. Hence there were no readily apparent distinctions between those who continued and those who dropped out of the testing procedures. The reduction in sample size can be attributed, at least in part, to the fact that neither weight loss nor changes in body composition were occurring in these individuals. Understandably, the EXP subjects assumed that their body composition was also unaffected. Therefore, the testing periods may have been viewed as not being worth the time and effort required to participate. This may be especially true if one considers that the nature of the hydrostatic weighing procedure is often anxiety provoking. Also, the women subjects had to wear swimming attire for the hydrostatic weighing and skinfold test in front of a male investigator and a male laboratory assistant. This may have caused an additional feeling of uneasiness among subjects. In this regard, various self-monitoring tests, such as body circumferences and the fit of clothes, may be more appropriate than laboratory tests conducted at three month intervals. Such tests can be administered by the participant 63 herself in a private setting, with immediate feedback, and the opportunity for a greater frequency of testing. The problem of participants prematurely discontinuing a weight loss treatment, or in this case the body composition testing, after being unsuccessful appears to be inherent in any weight loss treatment program. Generally, participants are more likely to dropout of treatment, or fail to lose a substantial amount of weight, when they are unsuccessful in the first few weeks of the program (Wilson, 1985). In lieu of the insignificant weight loss in the present study, the three EXP subject's unwillingness to continue their participation in the body composition testing was probably unavoidable. The EXP group's adherence was not greater than that of CON, as was hypothesized. The CON group adherence rate, 81.6%, was in accord with the adherence rates of all previous weight loss programs run on the Michigan State University campus. Nine other weight loss programs, including the control program used in this study, have been run in various academic buildings. These sites reveal a mean adherence rate of about 79% and range of 71.6%-90.0% (B.E. Mavis, personal communication, January 24, 1991). It may be speculated that the low EXP adherence rate may be due to differences in either the EXP weight loss program, the EXP worksite itself, or a combination of the two. Differences in subject characteristics, program leaders, previous weight loss attempts, attendance at program meetings, and seasonal effects are all addressed as potential causative factors in this discussion section. 64 Initially, EXP and CON subjects were to be composed of randomly assigned volunteers from a single worksite. This would have eliminated any differences between the two worksite programs, which may have been the major confounding variable in this study. All subjects would have been employed at the same worksite and would have received the exact same weight loss program. Unfortunately, there was a lower than expected number of participants at worksite A, and hence not as many volunteers for the study. In order to obtain a large enough sample size a previous behavioral weight loss program from another worksite was chosen for the matching of the control group. Worksite B was determined by the participant's demographic characteristics, as well as the worksite itself, which appeared to be most similar to that of EXP. This, however, may have not been a correct assumption. Evaluation of demographic characteristics revealed that participants involved in the MSU Worksite Weight Loss Program, including those in EXP, do not appear to be substantially diverse in nature. Age, male-female ratios (within each program), employment level status (faculty, staff, or graduate student), and number of dropouts appear to be similar in each program. Therefore, available demographic characteristics do not explain the difference in adherence rates between EXP and other sites as these data appear to be similar for all participants. There is an important dissimilarity however, in the program design between the EXP weight loss program and that of CON. In the two programs, different group leaders were used. This is an important factor when one considers that the group leader is the primary motivator of participants, 65 and he/she directs the topics to be covered at the weekly meetings. If participants perceive the group leader as unqualified or insensitive, this may adversely affect their weight loss efforts (Wilson, 1985). The group leaders of both the EXP and CON programs had run previous weight loss programs, and so experience of the program leader should not have adversely affected the adherence results. Nevertheless, statistical analysis of their respective adherence rates revealed that the CON leader had obtained a significantly higher (p < .001) rate of adherence. While the previous adherence rates of the two group leaders' programs may be a possible causative factor in the poor performance of the EXP program, the EXP participants were not less (or more) satisfied with their program compared to CON or other previously run programs. Certainly, one might expect that EXP participants would be less satisfied with their program based on their poor results. Program evaluation surveys were distributed at the end of each program to evaluate participant satisfaction. These surveys also showed no substantial difference of opinion with regard to the ability of the program leaders, the nature of the program materials and handouts, or the program in general. The program evaluation data are provided in Appendix K. Although the surveys suggest that different program leaders was not a primary contributor to the lower adherence rate of the EXP program, analysis of the adherence rates of the leaders' past programs suggest the contrary. Therefore it is difficult to ascertain the impact different group leaders had on the success of the two programs. 66 Another possible confounding difference between the EXP group and the CON group (and other worksites on the MSU campus) may have been the number of previously failed weight loss attempts by EXP subjects. All subjects reported attempting to lose weight at least once during the two years previous to the program at their worksite, and eight of the subjects were previously involved in a formal weight loss program (e.g., Weight Watchers). Unfortunately, data outlining previous weight loss attempts on CON subjects or other MSU Weight Loss participants could not be obtained due to logistical considerations. Therefore it is uncertain if the previous weight loss attempts were a major difference between EXP and CON. This information may, however, provide insight into the insignificant weight loss of EXP subjects. Several studies (Adams, et al., 1986; Hoiberg et al., 1984; Jeffery, Bjornson-Benson, Rosenthal, Lindquist & Johnson, 1984b; Jeffery, Snell & Forster, 1985b) have found a negative correlation between previous weight loss attempts and success in weight loss programs. Hoiberg and others (1984) determined that a history of few dieting attempts was positively correlated with weight loss in U.S. Navy personnel. However, it should be noted that Weiss (1977) and Wilson (1985) purpose that previous weight loss efforts are not related to treatment outcome. Weiss (1977) reviewed four studies reporting results on previous dieting attempts and found only one which showed a negative relationship to weight loss, while the three others revealed no relationship. Wilson (1985) has concluded that weight loss history has not been proven effective as a predictor of future weight loss success. Still, some feel that if an individual has a 67 previous history of weight loss failures, this may lead to low levels of self-efficacy, which have been shown to hinder weight loss (Hoiberg et al., 1984; Weinberg, Hughes, Critelli, England & Jackson, 1984). From a physiological standpoint, repeated dieting - weight loss followed by weight regain (weight cycling) - may lead to an increased metabolic efficiency for storing calories (Blackburn et al., 1989; Brownell, Greenwook, Stellar & Shrager, 1986). Therefore individuals with a history of caloric restriction may find subsequent weight loss more difficult. .The effect of repeated weight loss and regain was first studied in rodents. Brownell and colleagues (1986) found that the rate of weight loss was two times slower during a second restriction period compared to the first. These cycled animals were also found to have a four- fold increase in food efficiency (the degree of weight change per unit of food intake). A recent study (Blackburn et al., 1989) has determined that a similar process may occur in humans. In this study, subjects underwent two 72 day cycles of protein sparing modified fasts. The rate of weight loss was significantly slower during the second cycle. A physiological mechanism for this decreased rate of weight loss may lie in the observations of Leibel & Hirsch (1984). Their study found that when obese humans lost a substantial amount of weight, there is a concomitant decrement in energy needs, much less than could be predicted for by the change in body mass. A variety of mechanisms have been proposed to account for an "increased metabolic efficiency" and decrease in calorie requirements, including decreases of locomotor activity, sympathetic nervous system activity, and resting 68 metabolic rate of remaining lean tissues. Furthermore, it may be that an increased efficiency of nutrient absorption across the gastrointestinal tract, carbohydrate and water accumulation, and gut filling (Gray, Fisler & Bray, 1988) may be occurring. Recently there has been support for the notion that a decrease in resting metabolic rate is the controlling mechanism. Steen, Poolinger & Brownell, (1988) studied high school wrestlers with a history of repeated cycles of weight loss and regain. These athletes were shown to have significantly lower resting metabolic rates compared to non- cycling wrestlers. Hence, having many previous attempts at weight loss through dieting may cause a decrease in metabolic rate and calorie requirements, making subsequent attempts at weight loss more difficult. It is not known at this time exactly how many of these cycles are required for a significant decrement in metabolic rate to occur. Examination of the present data revealed a correlation in the EXP group between attendance at weekly meetings and adherence to contracts of r = 0.58. The EXP group also had a correlation of r = 0.34 between attendance and weight loss. Neither of these correlations was statistically significant. The EXP group attendance at meetings averaged 69% (range= 100 -44) of the time. Unfortunately, attendance of the CON group was not recorded. Of the nine previously run MSU Weight Loss programs, five kept track of attendance, which produced a mean attendance of 81% (97.8 - 50.0%). Although a causal relationship between attendance and adherence cannot be inferred, data reported in the literature (Adams, et al., 1986; Holmes, Ardito, Stevenson & Lucas, 1984; Jeffery et al., 1984b; Dahlkoetter, Callahan & Linton, 1979; Eufemia and 69 Wesolowski, 1985; Perri, McAdoo, McAllister, Lauer & Yancey, show a strong association between attendance at program meetings and success in weight loss efforts. Therefore, it is felt that the low rate of attendance in the EXP group may have contributed to their poor adherence rate. As to why the EXP group had such low attendance is uncertain, although two suppositions exist. It may be that the EXP worksite was much different than the other sites in regard to the amount of support from upper management and supervisors. Although the president of the university announced that all employees were to be given "release time" to participate in health promotion activities, this did not appear to be the case at Worksite A. For instance, because of other work-related commitments, EXP subjects experienced difficulty agreeing on a set time for the weekly meeting. Also, the most frequent anecdotal reason for missing a weekly meeting was due to "not being able to get away from work". The other potential causative factor for the poor attendance is that of a seasonal effect on program participation. The EXP program was run primarily in the summer months (April-October). CON plus five of the other nine previously run weight loss programs at MSU took place in the winter (January-June). In this academic setting, opportunities for vacation and travel are much greater during the summertime. When surveyed, eight out of the 10 EXP subjects reported being on vacation for at least one week during the program's time frame. CON subjects could not be contacted. Of course, besides attendance, vacationing could 70 have been directly detrimental to weight loss efforts. This was dramatically illustrated by one EXP subject who had lost about ten pounds and went on vacation for two weeks. On her return, she regained approximately eight pounds. Besides a possible seasonal effect and a lack of upper management support, there may have been other differences in the worksite of EXP subjects compared to other sites which may have contributed to the poor adherence in the EXP program. Numerous anecdotal reports were given by EXP subjects regarding the common and ritualistic "social eating" that occurred at their worksite. One traditional occurrence was that of individuals bringing homemade pies, cakes, brownies, and other baked goods to the worksite for others to enjoy. In addition, this worksite contained a small cafeteria, which was not available at CON worksite. This may have made the procurement of food and "social eating" relatively easy. Under these circumstances, EXP subjects most likely did not receive much social support to control eating patterns from co-workers. Social support has been found to decrease attrition from treatment, improve weight loss, and improve weight loss maintenance (Colletti & Brownell, 1982). One's co-workers and peers are thought to be a valuable source of support during the weight loss process (Perri, McAdoo & Spevak, 1984). Conceptually, the body Composition testing was to be used as a method to provide reinforcing feedback, which ideally would lead to an increase in self-efficacy and greater success in the behavioral weight loss program. In this study, the testing could have had a contrary effect. 71 Instead of the body composition testing providing reinforcing feedback, EXP subjects may have actually gotten negative feedback, which could be followed by a subsequent decrease in self-efficacy and therefore the low adherence rate. In order for the body composition testing to provide reinforcing feedback, it would have to be perceived by the EXP subjects as a successful experience. In retrospect, the results of even the initial testing period could potentially have been viewed as failure. For example, a participant in the present study may have known for many years that she was overweight when the body composition testing revealed that her percent body fat was about 50%. This merely confirmed the fact that she had an overabundance of fat and needed to lose weight. More importantly, this could have been perceived as negative feedback and may have decreased her self-efficacy level to the point where losing weight would now be more difficult. Then at the three month testing period, there was more negative feedback when she was informed that there was no substantial body fat loss. Hence, self-efficacy levels would have declined even further. This aforementioned pattern of decreasing self-efficacy with unsuccessful testing experiences are similar to that found when individuals were exercise tested three weeks after a myocardial infarction (Ewart, Taylor, Reese & DeBusk, 1983). Patients whose exercise treadmill tests were limited by angina pectoris (and therefore unsuccessful) were found to have subsequent lower levels of self efficacy than those patients who were not symptom-limited in the test. Many of these same patients had relatively high levels of self- efficacy before exercise testing was conducted. These 72 individuals were also found to be less successful in an ensuing exercise program as they had lower peak heart rates and work loads compared to patients whose self-efficacy increased or remained high after treadmill testing. It may be plausible to suggest that unsuccessful body composition tests (or failure to lose fat) have similar affects on self- efficacy. The findings of this study have provided a direction for future investigations in this area. Because of an inadequate research design in the present investigation, the effects of body composition testing on the success of behavioral weight loss programs is still to be determined. This study should be repeated, using EXP and CON subjects from one worksite, and therefore a single weight loss program. This will isolate the effects of the body composition testing by controlling for differences between two worksite environments as well as differences in the weight loss program itself. Finally, one should not interpret the results of this study to mean that body composition assessments are of no value for those participating in a weight loss program. Such assessments may be critical in evaluating the safety and effectiveness of the program, as well as providing participants with important reinforcing feedback. Even in ‘the present study, subjects observed where fluctuations in body weight could be attributed to a retention or depletion of body water, something that a scale weight would not provide. CHAPTER V SUMMARY, CONCLUSIONS AND RECOMMENDATIONS Summary Obesity is a contributing factor to many diseases. Unfortunately, weight loss programs have historically been plagued by insignificant weight loss and high dropout rates. The purpose of this study was to enhance participant adherence and weight loss during a six month behavioral weight loss program via a series of body composition measurements. It was hypothesized that the knowledge of results of such tests would provide additional informative feedback concerning the amount and anatomical location of fat loss, and therefore motivate participants to adhere to the weight loss program. Ten healthy females, 25-53 years of age, served as subjects who received both the behavioral weight loss program and body composition testing (EXP). Ten similar females who underwent the behavioral weight loss program two years previously, without body composition testing, served as controls (CON). The CON program was run at a separate different worksite and utilized a different program leader than EXP. Body composition of the EXP subjects was assessed by skinfolds, body circumferences, and hydrostatic weighting before, at 3 months, and after the 6 month program. There were no statistically significant differences in any of the body composition measurements in the EXP group as 73 74 a result of the six month behavioral weight loss program. The CON group lost (6.3 i 1.4 kg) significantly more (p < 0.05) weight than EXP (1.8 f 1.4 kg). Similarly, the adherence rate of CON 81.6 t 4.3 was significantly greater (p < 0.01) than EXP (52.6 i 6.0). W Due to a lack of success of the weight loss program undertaken by EXP subjects, and various extraneous factors within the research design, the effects body composition testing on adherence and weight loss cannot be definitively concluded. It is hypothesized that the insignificant amount of weight loss by EXP subjects may be due to substantial differences in these subjects, their worksite, or of their weight loss program compared to CON. Recommendation This study should be replicated, drawing subjects from a common worksite unit and undergoing a single weight loss treatment. Subjects should be randomly assigned to EXP or CON. In this way, the effects of body composition testing on adherence may be isolated from the various extraneous factors found in the present study. APPENDICES APPENDIX A INFORMED CONSENT FORM 75 APPENDIX A CENTER FOR THE STUDY OF HUMAN PERFORMANCE Informed Consent fog Participation Th Research Activities Participant Date Principal Investigator Title of Project Effect of Adherence tp a Weight LossiNutrition Program on Body Composition Purpose To detegpine the effeetg of physiologieal gestghg end behavior change 0 we ht loss n sedent r middle-a d m and women l. I hereby authorize Dr. M. A. Rogegs and/or such assistants as may be selected by him for use now or at a later time. to perform upon me the following procedures in connection with a research project: Underwater weighing and skinfolds to determine percent body fat before. at 3 months and after 6 months of a behavioral study that uses written contracts and monetary incentives to maximize adherence. Enlist me as a participant in the control group or the experimental group that receives all of the physiological tests. Enroll me in a written agreement where I contract to lose a certain amount of weight per week for 6 months. I realize that the $40 I give to the program staff is not a payment but a deposit placed in escrow that is returned upon my successful completion of the program. Attend 15 program meetings over 6 months where weight loss/nutrition information will be presented. 2. I understand the possible benefits to myself or others associated with the procedures described above. Although benefits are not guaranteed, they may include: The information obtained from this study may contribute to a better understanding of the potential ways to increase adherence to a weight loss program that bring about a reduction in % body fat. 3. I understand certain hazards and discomforts might be associated with the procedures described above. These are: Subject may become anxious when breathing underwater with a mouthpiece/ airway apparatus. 4. I understand the following alternative procedures are available that would be advantages to me: This is a research procedure. Participation is voluntary. 76 APPENDIX A Continued 5. I understand that the investigator is willing to answer any inquires I may have concerning the procedures herein described. All the inquiries I have at this time have been answered. I understand the confidentiality of my records will be maintained in accordance with applicable state and federal laws. 6. I understand that my participation is voluntary and that I may refuse to participate and/or withdraw my consent and discontinue participation in the project at any time without penalty or loss of benefits to which I an otherwise entitled. 7. I understand that if I an injured as a result of my participation in this research project, Michigan State University will provide emergency medical care if necessary. I further understand that if the injury is not caused by the negligence of MSU I am personally responsible for the expense of this emergency care and any other medical expenses incurred as a result of this injury. 8. To the best of my knowledge I am not pregnant, and if I do become pregnant I will notify the principal investigator. I will contact Dr. Marc Rogers with any questions that I have concerning the study. 9. I have received a copy of this informed consent which I have read and understand. I hereby consent to the performance of the above procedures upon me. Parent or legal guardian's signa- Participant's Signature ture on participant's behalf if less than 18 years of age. Auditor WitnESs' Signature, if witness is present I have explained the above to the participant (or parent or guardian) on the date stated on this Informed Consent for Participation in Research Activities. Investigator's Signature APPENDIX B CIRCUMFERENCE MEASUREMENT TECHNIQUES 77 APPENDIX B MICHIGAN STATE UNIVERSITY CENTER FOR THE STUDY OF HUMAN PERFORMANCE Technigues [g Measurino girgumferencesl- Abdominal Circumference The abdominal circumference is an anthropometric indicator of subcutaneous and deep adipose tissue. The subject Stands with the arms by the sides and feet together, without clothing, abdomen relaxed. Measuring tape is placed around the subject at the level of the greatest anterior extension of the abdomen in the horizontal plane (usually at the level of the umbilicus). The tape is held snug (with assistant) against the skin without compressing the tissues, measurement made at the end of a normal expiration to the nearest 0.1 cm. Buttocks (hi2) Qircumference Hip circumference is a measurement of external pelvic size that reflects the amount of regional adipose tissue, i.e., lower body fatness. The subject Stands erect while the measurer squats at the side of the subject to note the maximal extension of the buttocks. A tape is placed around this point in a horizontal plane such that the zero end of the tape is below the measurement value. Measurement recorded to the nearest 0.1 cm. Qalf Circumference 'The subject stands with the feet ~20 cm apart and weight distributed equally on both feet. The tape is positioned horizontally around the calf at the maximum circumference in a plane .L to the long axis of the tibia. Measured to the nearest 0.1 cm. lAnthrgmgzmctric Standardizatign Referencg Manual. T. G. Lohman ct al., Ed. Human Kinetics Publishers, Champaign, Ill.. 1988. APPENDIX C SKINFOLD PILOT STUDY DATA 78 APPENDIX C SKINFOLD PILOT STUDY DATA Correlation Coefficients between Week 1 and Week 2 Measurements Site Correlation Coefficient Tricep 0.937 Bicep ‘ 0.954 Subscapular 0.931 Suprailliac 0.969 Umbilical 0.855 Thigh 0.971 Correlation Coefficients between Principle Investigator and Proficient Technician Site Correlation Coefficient Tricep 0.983 Bicep 0.985 Subscapular 1.000 Suprailliac 0.911 Umbilical 0.923 Thigh 0.975 APPENDIX D SKINFOLD REGRESSION EQUATIONS 79 APPENDIX D SKINFOLD REGRESSION EQUATIONS Regression equations for predicting body density (Y) from the log of total skinfold thickness of four sites (biceps, triceps, subscapular and suprailiac) (X), as presented by: Durnin, J.V. & Rahaman, M.M. (1967). The assessment of the amount of fat in the human body from measurements of skinfold thickness. British Journal 9; Nutrition, 21I 681- 689. Subjects Men Y = 1.1610 - 0.0632X +0.0060 Women Y = 1.1581 - 0.0720X +0.0096 Boys Y = 1.1533 - 0.0643X +0.0083 Girls Y = 1.1369 - 0.0598X +0.0082 APPENDIX E HYDORSTATIC WEIGHING FORMULAS 80 APPENDIX E HYDROSTATIC WEIGHING FORMULAS Residual Lung Volume (Adapted from Rahn et al., 1946) (Nb - No) (B - PHZO) (310) (Na - Nb) (B - 47) (373 - Tg) VRLBTSP = Volume of gas remaining in lungs after exhalation (ml) V02 = Original value of oxygen in bag and tubing (ml) (expressed at ambient temperature and pressure and with oxygen saturated with water) Nb = Nitrogen in bag after rebreathing (%) NC = Nitrogen in bag before rebreathing (%) Na = Nitrogen in alveoli prior to rebreathing (use constant of 78%) B = Barometric Pressure (mmHg) PHZO = Partial pressure of H20 at spirometer temperature T9 = Temperature of gas in syringe (centigrade) DS = Dead space in valve (m1) Db Db Wa Ww* Dw VGI Body Fat 81 APPENDIX E continued Body Density = Wa (Wa - Ww*) - (VRL + VGI) Dw = Body density (g/ml) = Body weight in air (q) = Body weight in water corrected for mouthpiece buoyancy = Density of tank water at water temperature of tank = Volume of gas remaining in lungs after exhalation (ml) = Volume of gas in intestinal tract (VGI = 1.4 x Wa) Bod Fat (%) (Siri, 1961) 4 x 100 (%) = [(4.95/Db) - .5] APPENDIX E DIAGRAM OF THE HYDROSTATIC WEIGHING SYSTEM (Zelasko, 1984) 1 Sumfimwm UZHEOHWB OHB= Ema. .mO EwdHD .m XHszmm< H \g“! \\\~ — (\l \l\ “g E I 82 APPENDIX G BODY COMPOSITION DATA COLLECTION SHEETS 83 AUEPEDHIIXICS SKINFOLD AND CIRCUMFERENCE DATA SHEET HICHIGAN STATE UNIVERSITY CENTER FOR THE STUDY OF HUMAN PERPORHANCE Body Fat Assessment Name - Date ~ VT(k§) Weight kg Height BHI_________HT(m ) Tech Study Sk fold Tgia; l Igial 2 T al 3 Average Triceps Biceps Subscapular Suprailiac Sum (4) Umbilical Front Thigh Chest Circumference Abdominal Buttocks Calf . 152...:— .=_...... ... 22.2.33. .3: :1 >_:.:_._.:3; $3.232. 757—3.... : 3:3 .3: C...:.3> .c_._..m0u m. .3...— .. .....----.- .-...-- -. -:|-.- .-. -.-- --- s. -. -..-.-- ... -- -. -.. 1-.:..-;....;.fi--....-u.- - -.... .....J lull! 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"Lofin—u 3.65.8 u 3 .e Ill: , _. . u u . . ax e_< :. a. ea: c. on .dEop . cam :02 Q _\ANn ...ev ... be a aching: ....3.03 mam «Lahm Oh ..e. u to. com: :o_.e:co _c_m .c >eo: a.oa omc_e>m < mmocd "moaoz "tobcu. u _:.oc o. .eeop u, .22: o. .eEop a: 55 .mocd Eecmoc: .a__eQ to.ex ..o: c_< .eem .eo.m 0p tots: «z xccr 800: o mmmua no-:coxs_ "..o...w i 11.! -1- unrlllzllzeosuoom: it, uo+cuoao \ \II: o.e: exfilllllllil.>ca .c os__ Eutlllllli .za.o: Illiyllllxlll ewe—m .0 can: OE - oa< Em u> ilialel.-l:il---:- >::.m In ll-:olnlll. .oz .oEm:. .ooqasm wee—ua_:o.au a:.ga_o3 coucxeoeez uuz==hm m:~ ecu :upzuu -- >p_m¢u>_z: up= U xHszmmc 2&4 APPENDIX H INDIVIDUAL SUMMARY OF RESULTS FORM 85 APPENDIX H Name Body weight: (lb) (kg) Skinfold measurements (mm): Triceps Biceps Subscapular (back) Suprailiac (hip) Umbilical Front Thigh Cigcumference measurements (cm): Abdominal Buttocks Calf 3 Body Fat: Skinfold estimation Underwater weighing estimation Lean Body Mass (Body weight minus fat weight): * Most accurate estimate (lb) APPENDIX I RAW DATA 86 APPENDIX I RAW DATA EXP Group Data Age (yrs), Height (cm), and Body Mass Index (BMI) Subject Age Height BMI 1 29 151.6 21.8 2 53 166.5 26.4 3 25 167.0 31.1 4 45 169.5 26.6 5 52 159.9 32.7 6 41 166.8 24.2 7 34 167.3 27. 8 51 160.7 32.4 9 ' 50 160.6 34.9 1 43 181.5 28.0 x 42.3 165.1 28.5 t SE + 3.2 i 2.5 i 0.4 Bodyweight (kg) Subject Initial Mid Post 1 50.2 51.0 51.5 2 73.3 72.7 70.0 3 86.8 84.0 80.5 4 76.3 79.0 81.6 5 83.7 81.5 82.0 6 67.4 67.7 67.5 7 75.9 70.6 68.0 8 83.6 82.5 83.0 9 90.0 86. 82.5 1 92.2 95.7 95.0 X 77.9 77.1 70.9 1- 3.2 t 3.9 + 3.8 87 Tricep Skinfold (mm) Subject Initial Mid Post 1 19 24 19 2 27 28 25 3 35 35 34 4 22 25 25 5 33 33 32 6 33 34 33 7 25 25 21 8 27 34 32 9 26 32 3O 10 30 31 29 X 28 30 28 :SE +2 1-1 :2 Bicep Skinfold (mm) Subject Initial Mid Post 1 8 14 7 2 23 21 20 3 27 24 17 4 14 20 15 5 23 23 22 6 17 20 19 7 15 15 10 8 17 26 16 9 20 25 25 10 20 22 22 X 18 21 17 +SE +2 i1 :2 Subscapular Skinfold (mm) Subject Initial Mid Post 1 11 12 10 2 21 14 16 3 26 25 22 4 20 24 21 5 25 26 25 6 19 16 18 7 24 19 14 8 23 23 27 9 31 34 33 10 11 12 13 X 21 21 20 +33 +2 +2 3:2 88 Suprailiac Skinfold (mm) Subject Initial Mid Post 1 10 11 11 2 12 9 11 3 28 28 24 4 24 29 28 5 27 31 33 6 21 24 22 7 24 23 20 8 24 31 25 9 31 32 30 10 15 26 20 X 22 24 22 i-SE :2 1-3 :2 Umbilical Skinfold (mm) Subject Initial Mid Post 1 7 12 7 2 19 18 16 3 30 25 20 4 24 33 32 5 36 36 36 6 20 20 20 7 16 15 15 8 24 34 32 9 24 30 29 10 16 26 25 X 22 25 23 +SE +3 +3 :3 Thigh Skinfold (mm) Subject Initial Mid Post 1 22 27 24 2 28 31 30 3 38 4O 33 4 32 31 30 5 32 36 37 6 31 32 30 7 32 27 24 8 30 37 38 9 32 45 43 10 29 35 36 X 31 34 33 tSE 1‘1 +2 :2 89 Abdominal Circumference (cm) Subject Initial Mid Post 1 69 69 68 2 77 80 81 3 86 86 81 4 86 86 88 5 101 101 102 6 78 74 75 7 82 78 75 8 93 94 95 9 97 98 96 10 86 86 84 X 85.5 85.2 84.5 + SE + 3.1 + 3.3 + 3.4 Buttocks Circumference (cm) Subject Initial Mid Post 1 90 89 90 2 110 109 107 3 114 111 108 4 107 107 109 5 117 113 118 6 109 111 110 7 108 99 99 8 114 113 114 9 117 115 114 10 118 124 124 X 110.4 109.1 109.3 SE i 2.6 i 2.9 t 3.0 Calf Circumference (cm) Subject Initial Mid Post 1 32 32 32 2 36 35 34 3 45 45 43 4 42 43 44 5 39 38 38 6 34 36 36 7 42 38 39 8 42 42 42 9 43 42 42 10 45 45 44 X 40.0 39.6 39.4 SE + 1.5 + 1.4 + 1.4 90 Skinfold % Body Fat (%) Subject Initial Mid Post 1 20 30 26 2 34 33 33 3 40 40 37 4 34 38 36 5 39 40 40 6 36 36 36 7 36 34 31 8 36 40 38 9 39 42 41 10 34 36 35 X 34.8 36.9 35.3 SE + 1.8 + 1.2 + 1.4 Hydrostatic Weighing % Body Fat (%) Subject Initial Mid Post 1 30 27 28 2 47 45 42 3 43 43 40 4 41 38 38 5 50 50 51 6 43 40 42 7 29 25 22 8 48 44 44 9 48 44 41 10 47 49 48 X 42.6 40.5 39.6 4; SE + 2.4 + 2.7 + 2.8 Lean Body Mass (kg) Subject Initial Mid Post 1 35.5 37.3 35.9 2 39.1 40.0 40.0 3 49.1 47.7 48.2 4 45.5 48.7 50.9 5 41.4 40.0 39.5 6 38.6 40.9 39.5 7 54.1 52.7 53.2 8 43.6 46.4 46.4 9 46.8 48.2 47.7 10 58.2 60.9 61.4 X 45.2 46.3 46.3 3: SE + 2.3 i 2.3 + 2.5 91 Adherence (%), Weight Lost (kg), Attendance (%), & Amount Contracted to Lose (lbs.) Subject Adherence Weight Lost Attend. Amt.Con. 1 31 +1.3 69 0.5 2 63 3.3 81 1.0 3 38 6.3 44 1.5 4 38 +5.3 44 1.0 5 63 1.7 100 0.5 6 56 +0.1 53 1.0 7 81 7.9 75 0.5 8 31 0.6 56 0.5 9 81 7.5 100 1.0 10 44 2.8 81 1.0 X 52.6 1.8 70.3 0.9 I SE 1 6.0 11.4 + 6.6 10.1 CON Group Data Age (yrs), Height (cm), BMI Subject Age Height BMI 1 48 157.5 30.6 2 43 167.6 26.7 3 47 157.5 31.7 4 52 157.5 23.9 5 43 167.6 30.1 6 28 172.7 26.8 7 57 157.5 31.2 8 60 152.4 37.8 9 54 170.2 32.0 10 48 167.6 21.9 X 48.0 162.8 29.3 t SE + 2.8 i 2.2 i 1.4 CON Group Body Weight (kg) Subject Initial 3 Month 6 Month 1 75.9 72.3 69.5 2 75.0 64.5 56.8 3 78.6 76.4 76.3 4 59.5 55.0 54.3 5 84.5 80.9 76.8 6 80.0 75.9 75.0 7 77.3 72.3 70.9 8 87.8 85.2 83.3 9 92.7 91.8 90.0 10 61.4 59.1 56.4 X 77.3 73.3 70.9 t SE i 3.3 i 3.6 + 3.8 92 Control Group Adherence (%), Weight Lost (kg) & Amount Contracted to Lose (1b.) Subject Adherence Weight Lost Amt. Contracted ... O O H XHmmqmmhuNH o x) 0) m u 01 oo HO‘U‘INfiO‘thleO‘ O O O O O O O O O O O O bUOQUlobUlewa OOONOI—‘HOOOHH O O O O O O O O O O O O NOUIOWOUIU'IU'IUIOO + U) M l+ b N H H Data of Nonéstudy Participants Q; the EXP Worksite Age (yrs), Weight Loss (kg), Attendance (%), Adherence (%) Subject Age Weight Loss Attend. Adherence 1 44 0.9 53 56 2 56 1.4 63 50 3 48 0.6 63 63 4 51 3.6 75 63 5 38 5.0 75 38 6 38 0.8 69 81 X 45.8 2.1 66.3 58.5 1- SE 35 3.0 10.7 + 3.5 i 5.9 APPENDIX J REPEATED MEASURES ANALYSIS OF VARIANCE TABLES REPEATED MEASURES ANALYSIS OF VARIANCE TABLES Tricep Skinfold 93 APPENDIX J Source df Sums of Squares Mean Square F Session 2 34.2 17.1 0.72 Error 27 641.0 23.7 Total 29 675.2 Bicep Skinfold Source df Sums of Squares Mean Square F Session 2 72.2 36.1 1.42 Error 27 686.5 25.4 Total 29 758.7 Subscapular Skinfold Source df Sums of Squares Mean Square F Session 2 7.2 3.6 0.08 Error 27 1272.3 47.1 Total 29 1279.5 Suprailiac Skinfold Source df Sums of Squares Mean Square F Session 2 41.6 20.8 0.37 Error 27 1529.2 56.6 Total 29 1570.8 94 Umbilical Skinfold Source df Sums of Squares Mean Square F Session 2 54.5 27.2 0.37 Error 27 1972.9 73.1 Total 29 2027.4 Thigh Skinfold Source df Sums of Squares Mean Square F Session 2 61.4 30.7 1.07 Error 27 773.8 28.7 Total 29 835.2 Abdominal Circumference Source df Sums of Squares Mean Square F Session 2 5 3 0.03 Error 27 2841 105 Total 29 2846 Buttocks Circumference Source df Sums of Squares Mean Square F Session 2 9.8 4.9 0.06 Error 27 2233.4 82.7 Total 29 2243.2 Calf Circumference Source df Sums of Squares Mean Square F Session 2 1.9 0.9 0.05 Error 27 532.8 19.7 Total 29 534.7 95 Hydrostatic Weighing % Body Fat Source df Sums of Squares Mean Square F Session 2 47.4 23.7 0.35 Error 27 1821.3 67.5 Total 29 1868.7 Skinfold % Body Fat Source df Sums of Squares Mean Square F Session 2 24.1 12.0 0.55 Error 27 592.6 21.9 Total 29 616.7 Lean Body Mass Source df Sums of Squares Mean Square F Session 2 38 19 0.07 Error 27 7036 261 Total 29 7074 EXP Group Body Weight Source df Sums of Squares Mean Square F Session 2 16 8 0.05 Error 27 4075 151 Total 29 4091 CON Group Body Weight Source df Sums of Squares Mean Square F Session 2 205 102 0.80 Error 27 3445 128 Total 29 3650 APPENDIX K PROGRAM EVALUATION DATA 96 APPENDIX K PROGRAM EVALUATION DATA Eight participants in the EXP program and 10 from the CON program completed a program evaluation survey. Participants rated the degree to which they agreed with each of the following statements using the scale of: 1 = strongly disagree 2 = disagree 3 = neither agree nor disagree 4 = agree 5 = strongly agree na = not applicable The mean responses of EXP and CON are provided at the right of each statement. The Program Leader was: CON EXP 1. pleasant during the program 5.0 4.6 2. very helpful to me 4.7 4.3 3. knowledgeable about the subject 4.9 4.8 4. supportive and caring 5.0 4.6 5. motivatin 4.5 4.1 6. actively involved in the program 4.7 4.6 The Program materials, videotapes and handout were: 1. very helpful to me 4.7 4.6 2. interesting 4.4 4.4 3. informative 4.5 4.5 4. easy to understand 4.6 4.4 5. motivating 4.1 4.0 6. gave me enough information 4.0 4.1 Regarding the Progpam in general... 1. It helped me change my lifestyle 4.5 3.8 2. I learned some things which I will continue to use throughout my life 4.7 4.5 3. My participation has had a positive impact on my family 4.3 3.6 4. My participation has had a positive impact in my work area 4.5 3.4 5. I would recommend this program to others 4.9 4.4 6. The length of the program was about right 4.6 4.3 7. It helped me gain control of part of my life 4.6 4.1 The following questions asked participants how well they 97 APPENDIX K Continued liked different aspects of the program. used was: not at all important somewhat important very important behavioral contracts and goals for each session seeing and meeting with others who share the same concerns the program leader as a person being accountable to the program leader ' the materials and information the monetary incentives group discussions the program is held at your workplace being accountable to other members of your team N NNNNN Nb) 0 O O O O O O m UlO‘NU'lO‘ \00 The rating scale 3 N ch own-woo \OO O) N QNNNU) Nb.) REFERENCES Eeferenges Abrams, J.L. & Allen, G.J. (1974). 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