Path analysis of exercise treatment-induced changes in psychological factors leading to weight loss

Transfer or Compensation?

Abstract. This study tested the effects of exercise on eating behavior. The transfer hypothesis proposes that exercise leads to a generalization of healthy behavior and therefore an improved diet. The compensation hypothesis assumes that exercise leads to increased caloric intake in order to “compensate” for the energy expenditure. We tested these hypotheses for actual as well as imagined exercise. Female university employees or students (N = 227) were randomly assigned to three experimental groups: actual exercise vs. imagined exercise vs. control. After baseline data had been obtained, the participants engaged in a 5-minute experimental task and were then left alone with unhealthy snacks. Participants who had imagined themselves exercising (M = 101 kcal, SD = 128 kcal) consumed significantly fewer calories than did controls (M = 129 kcal, SD = 142 kcal), consistent with a transfer effect. Participants who had engaged in actual exercise, but had been distracted from thinking about exercise, consumed quantities (M = 127 kcal, SD = 111 kcal) similar to those consumed by controls. This study suggests that transfer effects are underpinned by psychological processes, such as goal activation, which should be investigated in the future.

Response Versus Nonresponse to Self-Regulatory Treatment Targets Is Not Discriminated by Personal Characteristics but Predicts Physical Activity, Eating Behavior, and Weight Changes in Women With Obesity

Background Results of behavioral weight-loss treatments vary widely, with mostly unsuccessful outcomes beyond the short term. Women with obesity participating in a new cognitive-behavioral weight-loss treatment were assessed on their responses to psychological targets. Methods Groups of responders ( n = 43) and nonresponders ( n = 48) were established post hoc. Results Age, race/ethnicity, education, income, body composition, physical activity, and eating behaviors at baseline were not discriminated between responders and nonresponders. Over both 6 and 24 months, responders improved significantly more in physical activity and fruit/vegetable consumption but not sweets intake. Weight loss over 6 and 24 months was significantly greater for the responder group at 8.1% and 8.6% versus nonresponders at 4.7% and 3.8%, respectively. Self-regulation change significantly predicted all behavioral changes, with mood change improving the predictive strength for only sweets intake. Discussion Although further research is required to determine the etiology of, and to maximize, positive responses, findings suggested prospects for treatment improvements.

Replication and Extension of the Weight Loss For Life Community-Based Treatment Protocol

Maintaining weight-loss beyond 6-9 months within behavioral treatments has been problematic. However, a social cognitive theory-driven, community-based curriculum emphasizing the generalization of physical activity-related self-regulation, to eating-related self-regulation (phase 1 treatment; n = 55), demonstrated success at both inducing lost weight over its initial 6 months, and maintaining that loss through month 24. The present replication study contrasted those outcomes with a phase 2 version of the year-long treatment (n = 74) that added a follow-up component during year 2 consisting of 5 brief phone interactions to reinforce self-regulatory skills. Participants were all women with obesity (body mass index 30-40 kg/m²; mean age = 48 years). In phase 2, the mean weight loss of 6.3% during baseline-month 6, and regain of 0.7% through month 24, did not significantly differ from phase 1. However, phase 2 methods were associated with significantly better retention of improvements in self-regulation, fruit/vegetable intake, and physical activity. For phase 2 results, second-year change in fruit/vegetable consumption completely mediated the significant relationship between self-regulation and weight change, and change in physical activity completely mediated the significant relationship between self-regulation and weight change, over the 2-year study. Findings suggest the importance of moderate physical activity and more intensive follow-up focused on self-regulation processes.

Exercise Predicts Long-Term Weight Loss in Women With Class 1 and Class 2 Obesity Through Effects on Emotional Eating and its Correlates

Background: The relationship between exercise and long-term weight loss is definitive. However, in deconditioned individuals, the basis of that relationship beyond minimal energy expenditures is unclear. Effects emanating from exercise’s proposed association with changes in emotional eating and its psychosocial correlates were tested. Methods: Women with class 1 (n = 67) and class 2 (n = 53) obesity, participating in a new community-based weight-loss treatment based on tenets of social cognitive theory, were assessed at baseline and Months 3, 6, 12, and 24 on weight and measures of exercise outputs, emotional eating, eating self-regulation, and negative mood. An exercise-support component was provided for 2 months prior to group nutrition-change sessions. Results: Improvements from baseline were significant on all measures but did not significantly differ by group. Although not for the initial 3 months, changes in exercise significantly predicted weight changes over 6, 12, and 24 months from baseline. However, only 26%–31% of the lost weight was directly attributable to exercise-related energy expenditures. Changes in emotional eating significantly mediated the exercise–weight-loss relationship, and changes in self-regulation and mood significantly mediated the exercise–emotional eating relationship. Conclusions: Findings supported exercise’s role in long-term weight loss primarily through psychosocial factors.

Directionality in the Relationship of Self-regulation, Self-efficacy, and Mood Changes in Facilitating Improved Physical Activity and Nutrition Behaviors: Extending Behavioral Theory to Improve Weight-Loss Treatment Effects

OBJECTIVE

To improve understanding of directionality in the dynamic relationships among psychosocial predictors of behavioral changes associated with weight loss.

METHODS

In women with obesity participating in a new behavioral weight-loss treatment that emphasizes physical activity (n = 53; body mass index = 34.7 ± 3.3 kg/m²), mediation and moderated-mediation models were fit to assess directionality in the self-efficacy-self-regulation change relationship and additional effects of mood change and its basis on fruit/vegetable intake and physical activity behaviors through month 6 and from months 6 to 24.

RESULTS

Self-regulation was a stronger predictor of change in self-efficacy than vice versa. Mood change did not moderate the relationships significantly between changes in self-efficacy and/or self-regulation, and weight loss behavior. Emotional eating significantly changed mediated relationships between changes in mood and fruit/vegetable intake through month 6 (95% confidence interval, -0.05 to 0.00).

CONCLUSIONS AND IMPLICATIONS

Findings clarified relationships of self-efficacy, self-regulation, and mood in the prediction of weight loss behaviors, and informed behavioral treatments for improved outcomes.

Psychosocial changes as correlates of weight regain vs. continued loss within 2-year trials of a self-regulation-focused community-based intervention

Although health-enhancing weight reductions are associated with behavioural treatments initially, a trajectory towards full regain typically begins within 6-9 months. Women with obesity (body mass index = 30-40 kg m^-2 ) who lost at least 3% of their baseline weight within two trials of a new cognitive-behavioural treatment incorporating physical activity prior to changes in eating behaviours, and either regained ≥50% of that weight over 2 years (Regain group, n=32) or continued to lose weight (ContinuedLoss group, n = 34), were assessed from months 6 to 24 on changes in weight-loss behaviours and psychosocial predictors of those behaviours derived from established behavioural theories. For the Regain group, significant decreases in physical activity and fruit/vegetable intake during months 12-24, from both months 6 to 24 and 12 to 24 in eating- and physical activity-related self-regulation and from months 6 to 24 in eating-related self-efficacy (i.e. feelings of ability), were found. No significant behavioural or psychosocial changes were found over those times in the ContinuedLoss group. Changes in self-regulation and self-efficacy completely mediated the relationship between changes in fruit/vegetable intake and group (Regain vs. ContinuedLoss) (McFadden's R ²  = 0.19 and 0.20, respectively), with self-regulation independently contributing to the explained variance. Changes over both months 6-24 and 12-24 in self-regulation significantly mediated the relationship between changes in physical activity and group membership (McFadden's R ²  = 0.24 and 0.27, respectively). Findings suggested that approximately 6 months after treatment initiation would be a suitable time to intervene with some bolstering methods, while approximately 12 months post-initiation would be most applicable for others.

Changes in self-efficacy for exercise and improved nutrition fostered by increased self-regulation among adults with obesity

Behavioral theory suggests that treatments that increase participants' use of self-regulatory skills and/or their feelings of ability (self-efficacy) will improve exercise and nutrition behaviors. In addition, psychosocial factors associated with increased exercise may carry over to improved eating. Self-regulation might enhance self-efficacy through feelings of ability to manage barriers to maintaining weight-loss behaviors. Sedentary adults with severe or morbid obesity (M age = 43 years; M BMI = 40.1 kg/m(2)) participated in a 6-month study within a community-based YMCA center. We randomly assigned participants to one of the two groups that incorporated the same cognitive-behavioral support of exercise paired with methods for controlled, healthy eating emphasizing either (a) self-efficacy (n = 138), or (b) self-regulation (n = 136) methods. Mixed model repeated measures ANOVAs indicated significant improvements in exercise- and eating-related self-regulation over 3 months, and exercise- and eating-related self-efficacy over 6 months. The Self-Regulation Treatment Group demonstrated greater improvements in self-regulation for eating and fruit and vegetable intake than the Self-Efficacy Group. Regression analyses indicated that for both exercise and eating, self-regulation change significantly predicted self-efficacy change. In separate equations, changes in exercise and fruit and vegetable intake mediated those relationships, and change in self-efficacy and the corresponding behavioral changes demonstrated reciprocal, mutually reinforcing, relationships. There was evidence of carry-over, or generalization, of both self-regulation and self-efficacy changes from an exercise context to an eating context. We discussed findings in terms of leveraging self-regulation to improve self-efficacy, and provide a rationale for why exercise is the strongest predictor of success with weight loss. Results may be used to inform future behavioral weight-management treatments through improved knowledge of relationships among theoretically derived psychosocial factors.

Psychosocial predictors of emotional eating and their weight-loss treatment-induced changes in women with obesity

PURPOSE

This study aimed at assessing whether psychosocial predictors of controlled eating and weight loss also predict emotional eating, and how differing weight-loss treatment methods affect those variables.

METHODS

Women with obesity (M = 47.8 ± 7.9 years; BMI = 35.4 ± 3.3 kg/m(2)) were randomized into groups of either phone-supported self-help (Self-Help; n = 50) or in-person contact (Personal Contact; n = 53) intended to increase exercise, improve eating behaviors, and reduce weight over 6 months.

RESULTS

A multiple regression analysis indicated that at baseline mood, self-regulating eating, body satisfaction, and eating-related self-efficacy significantly predicted emotional eating (R (2) = 0.35), with mood and self-efficacy as independent predictors. Improvements over 6 months on each psychosocial measure were significantly greater in the Personal Contact group. Changes in mood, self-regulation, body satisfaction, and self-efficacy significantly predicted emotional eating change (R (2) = 0.38), with all variables except self-regulation change being an independent predictor. Decreased emotional eating was significantly associated with weight loss.

CONCLUSION

Findings suggest that weight-loss interventions should target specific psychosocial factors to improve emotional eating. The administration of cognitive-behavioral methods through personal contact might be more beneficial for those improvements than self-help formats.

Psychosocial predictors of decay in healthy eating and physical activity improvements in obese women regaining lost weight: translation of behavioral theory into treatment suggestions

Regain of lost weight is a universal problem for behavioral treatments. An increased understanding of theory-based psychosocial predictors of decay in behavioral correlates of weight loss might improve treatments. Data were derived from a previous weight loss investigation of 110 women with obesity. A subsample from the experimental treatment who lost ≥3 % body weight and regained at least one third of that over 24 months (N = 36) was assessed. During months 6 through 24, there were unfavorable changes in behavioral (fruit/vegetable and sweet intake; physical activity) and psychosocial variables. Mood change predicted change in fruit/vegetable and sweet intake, with emotional eating change mediating the latter relationship. Change in self-regulation predicted changes in sweet and fruit/vegetable intake and physical activity, with self-efficacy mediating the self-regulation-fruit/vegetable intake and self-regulation-physical activity relationships. Findings suggest that after treatment-induced weight loss, addressing indicated theory-based psychosocial variables might mitigate decay in behavioral predictors of healthier weight.

Exercise Self-Efficacy Moderates the Relation between Anxiety Sensitivity and Body Mass Index and Exercise Tolerance in Treatment-Seeking Smokers

There is little known about factors that contribute to the comorbidity of cigarette smoking and obesity. The current study sought to test whether exercise self-efficacy moderated the relation between anxiety sensitivity (fear of internal sensations) and BMI and exercise tolerance among cigarette smokers. Smokers (n = 72; 50% female; M_cpd = 19.3, SD = 10.65) were recruited to participate in a smoking cessation treatment trial. During medical screen, we measured weight, height, and exercise tolerance (functional capacity) employing a standardized maximal exercise testing protocol. After adjusting for participant sex and cigarettes per day, exercise self-efficacy moderated the association between anxiety sensitivity and BMI, such that the positive association between anxiety sensitivity and BMI was significantly stronger when exercise self-efficacy was low. The same pattern of results emerged for exercise tolerance. Exercise self-efficacy moderated the association between anxiety sensitivity and exercise tolerance, such that the negative association between anxiety sensitivity and exercise tolerance was significantly stronger when exercise self-efficacy was low. Among smokers, anxiety sensitivity may be a risk variable that, directly and indirectly in the context of low self-efficacy for exercise, causes or maintains higher body weight and lower exercise tolerance.

Weight Loss and the Prevention of Weight Regain: Evaluation of a Treatment Model of Exercise Self-Regulation Generalizing to Controlled Eating

CONTEXT

For decades, behavioral weight-loss treatments have been unsuccessful beyond the short term. Development and testing of innovative, theoretically based methods that depart from current failed practices is a priority for behavioral medicine.

OBJECTIVE

To evaluate a new, theory-based protocol in which exercise support methods are employed to facilitate improvements in psychosocial predictors of controlled eating and sustained weight loss.

METHODS

Women with obesity were randomized into either a comparison treatment that incorporated a print manual plus telephone follow-ups (n = 55) or an experimental treatment of The Coach Approach exercise-support protocol followed after 2 months by group nutrition sessions focused on generalizing self-regulatory skills from an exercise support to a controlled eating context (n = 55). Repeated-measures analysis of variance contrasted group changes in weight, physical activity, fruit and vegetable intake, mood, and exercise- and eating-related self-regulation and self-efficacy over 24 months. Regression analyses determined salient interrelations of change scores over both the weight-loss phase (baseline-month 6) and weight-loss maintenance phase (month 6-month 24).

RESULTS

Improvements in all psychological measures, physical activity, and fruit and vegetable intake were significantly greater in the experimental group where a mean weight loss of 5.7 kg (6.1% of initial body weight) occurred at month 6, and was largely maintained at a loss of 5.1 kg (5.4%) through the full 24 months of the study. After establishing temporal intervals for changes in self-regulation, self-efficacy, and mood that best predicted improvements in physical activity and eating, a consolidated multiple mediation model suggested that change in self-regulation best predicted weight loss, whereas change in self-efficacy best predicted maintenance of lost weight.

CONCLUSIONS

Because for most participants loss of weight remained greater than that required for health benefits, and costs for treatment administration were comparatively low, the experimental protocol was considered successful. After sufficient replication, physician referral and applications within health promotion and wellness settings should be considered.

Theory-based psychosocial factors that discriminate between weight-loss success and failure over 6 months in women with morbid obesity receiving behavioral treatments

PURPOSE

To improve success rates of behavioral weight-loss treatments, a better understanding of psychosocial factors that discriminate between weight-loss success and failure is required. The inclusion of cognitive-behavioral methods and manageable amounts of exercise might induce greater improvements than traditional methods of education in healthy eating practices.

METHODS

Women with morbid obesity [body mass index (BMI) ≥40 kg/m(2)] were recruited for a treatment of supported exercise paired with either a cognitive-behavioral or an educational approach to eating change over 6 months. They were classified as either successful with (i.e., at least 5 % loss; n = 40) or failed at (no loss, or weight gain; n = 43) weight loss. Discriminate function analysis incorporated theory-based models of 1 (self-efficacy), 5 (self-efficacy, self-regulation, mood, physical self-concept, body satisfaction), and 3 (self-efficacy, self-regulation, mood) psychosocial predictors at both month 6, and change from baseline-month 6.

RESULTS

All three models significantly discriminated weight-loss success/failure (66, 88, and 87 % for success; and 81, 87, and 88 % for failure, respectively). Self-regulation had the strongest correlations within the multi-predictor models (0.90-0.96), and all variables entered were above the standard of 0.30 set for relevance. Participants in the cognitive-behavioral nutrition group demonstrated significantly greater improvements in all psychosocial variables and success with weight loss. Completing at least two sessions of exercise per week predicted success/failure with weight loss better than overall volume of exercise.

CONCLUSIONS

New and relevant findings regarding treatment-induced psychosocial changes might be useful in the architecture of more successful behavioral weight-loss interventions.

Cross-behavior associations and multiple health behavior change: A longitudinal study on physical activity and fruit and vegetable intake

This study aimed to examine the interrelation of physical activity and fruit and vegetable intake. The influence of stage congruence between physical activity and fruit and vegetable intake on multiple behavior change was also investigated. Health behaviors, social-cognitions, and stages of change were assessed in 2693 adults at two points in time. Physical activity and fruit and vegetable intake were assessed 4 weeks after the baseline.

Social-cognitions, stages as well as stage transitions across behavior domains were positively interrelated. Stage congruence was not related to changes in physical activity and fruit and vegetable intake. Physical activity and nutrition appear to facilitate rather than hinder each other. Having intentions to change both behaviors simultaneously does not seem to overburden individuals.

Successful behavior change in obesity interventions in adults: a systematic review of self-regulation mediators

BACKGROUND

Relapse is high in lifestyle obesity interventions involving behavior and weight change. Identifying mediators of successful outcomes in these interventions is critical to improve effectiveness and to guide approaches to obesity treatment, including resource allocation. This article reviews the most consistent self-regulation mediators of medium- and long-term weight control, physical activity, and dietary intake in clinical and community behavior change interventions targeting overweight/obese adults.

METHODS

A comprehensive search of peer-reviewed articles, published since 2000, was conducted on electronic databases (for example, MEDLINE) and journal reference lists. Experimental studies were eligible if they reported intervention effects on hypothesized mediators (self-regulatory and psychological mechanisms) and the association between these and the outcomes of interest (weight change, physical activity, and dietary intake). Quality and content of selected studies were analyzed and findings summarized. Studies with formal mediation analyses were reported separately.

RESULTS

Thirty-five studies were included testing 42 putative mediators. Ten studies used formal mediation analyses. Twenty-eight studies were randomized controlled trials, mainly aiming at weight loss or maintenance (n = 21). Targeted participants were obese (n = 26) or overweight individuals, aged between 25 to 44 years (n = 23), and 13 studies targeted women only. In terms of study quality, 13 trials were rated as "strong", 15 as "moderate", and 7 studies as "weak". In addition, methodological quality of formal mediation analyses was "medium". Identified mediators for medium-/long-term weight control were higher levels of autonomous motivation, self-efficacy/barriers, self-regulation skills (such as self-monitoring), flexible eating restraint, and positive body image. For physical activity, significant putative mediators were high autonomous motivation, self-efficacy, and use of self-regulation skills. For dietary intake, the evidence was much less clear, and no consistent mediators were identified.

CONCLUSIONS

This is the first systematic review of mediational psychological mechanisms of successful outcomes in obesity-related lifestyle change interventions. Despite limited evidence, higher autonomous motivation, self-efficacy, and self-regulation skills emerged as the best predictors of beneficial weight and physical activity outcomes; for weight control, positive body image and flexible eating restraint may additionally improve outcomes. These variables represent possible targets for future lifestyle interventions in overweight/obese populations.

Relationships Between Body Areas Satisfaction, Exercise, and Mood in Obese African American Women

Despite a rate of morbid obesity that is 2.5 times that of European American women, African American women have higher body areas satisfaction than any other ethnicities. Previous research suggested differences in African American women’s attitudes toward body image may contribute to a lack of motivation to engage in weight management behaviors, such as physical activity. In addition, factors such as self-efficacy, self-regulation, and mood have been shown to affect healthy behavior participation but have not been studied among obese African American women. This study investigated if changes from baseline to posttreatment in self-efficacy and self-regulation for exercise and mood mediatedthe association between changes in body areas satisfaction and physical activity. The study used archival data consisting of 109 obese African American women who participated in a 6-month weight management intervention. The relationship between changes in body areas satisfaction and physical activity was mediated by changes in self-regulation for exercise and mood but not by change in self-efficacy for exercise. These findings may help in devising treatments targeted at this population. Implications are discussed.

Sex differences in coping strategies in military survival school

A wealth of research has examined psychological responses to trauma among male military service members, but few studies have examined sex differences in response to trauma, such as coping strategies. This study assessed coping strategies used by male and female U.S. service members completing an intensely stressful mock-captivity exercise, compared strategies by sex, and assessed the relationship between coping and posttraumatic stress symptoms (PTSS). Two hundred service members (78% male) completed self-report surveys before and after mock captivity. Surveys assessed demographics, service characteristics, PTSS, and coping strategies used during mock captivity. Participants used seven coping strategies: denial, self-blame, religion, self-distraction, behavioral disengagement, positive reframing, and planning. Women used denial (p≤.05), self-blame (p≤.05), and positive reinterpretation (p≤.05) strategies more frequently than men, and they had higher PTSS levels following the exercise. Structural equation modeling showed that the relationship between sex and PTSS was fully mediated by coping strategies. The results of this study suggest that reducing the use of maladaptive coping strategies may mitigate PTSS among females. Future efforts should target improving coping during highly stressful and traumatic experiences.

Pilot testing a cognitive-behavioral protocol on psychosocial predictors of exercise, nutrition, weight, and body satisfaction changes in a college-level health-related fitness course

OBJECTIVE

Small-scale pilot testing of supplementing a required college health-related fitness course with a cognitive-behavioral exercise-support protocol (The Coach Approach).

PARTICIPANTS

Three classes were randomly assigned to Usual processes (n = 32), Coach Approach-supplemented: Mid-size Groups (n = 32), and Coach Approach-supplemented: Small Groups (n = 34) conditions.

METHODS

Repeated-measures analyses of variance (ANOVAs) assessed overall and between-class changes in the behavioral/physiological factors of exercise, fruit/vegetable intake, and body mass index (BMI); and the psychosocial factors of self-regulation, exercise self-efficacy, mood, and body satisfaction. Dependent t tests evaluated within-class changes. Multiple regression analyses tested prediction of exercise by changes in self-regulation, self-efficacy, and mood.

RESULTS

Significant improvements in self-regulation and fruit/vegetable intake were found in all classes. The Coach Approach-supplemented classes demonstrated significant increases in exercise. Significant improvements in BMI, self-efficacy, and body satisfaction were found in only The Coach Approach-supplemented: Small Groups class. Psychosocial changes predicted increased exercise. Self-regulation was the strongest contributor.

CONCLUSIONS

Overall, results were positive and warrant more comprehensive testing.

Temporal aspects of psychosocial predictors of increased fruit and vegetable intake in adults with severe obesity: mediation by physical activity

Effective and reliable obesity treatments are lacking because of a poor understanding of the health behavior change process. Community-based organizations with the capacity to train existing staff members are particularly well-positioned to implement evidence-based treatment protocols to impact obesity-related behaviors such as unhealthy eating and lack of physical activity. The aim of this study was to assess temporal aspects of psychosocial predictors (self-regulation, mood, and self-efficacy) on increased fruit and vegetable intake in adults with severe obesity, while also accounting for mediation by physical activity volume. A 6-month, randomized field investigation was conducted. Severely obese adults volunteered for behavioral support of physical activity coupled with nutrition education (n = 73) or cognitive-behavioral methods for nutrition change (n = 71). Improvements in self-regulation, mood, self-efficacy, fruit and vegetable intake (FV), and physical activity (PA) were significant, with significantly greater self-regulation at month 6 for the cognitive-behavioral group. Increase in FV was predicted by changes in the above psychosocial variables over 6 months, with mood change over 3 months also a significant predictor. Change in PA mediated the above relationships, with a reciprocal effect between changes in PA and FV. Findings have implications for the large-scale behavioral treatment of obesity.

A model of environmental correlates of adolescent obesity in the United States

PURPOSE

The purpose of this study was to test a conceptual model of proximal (home) and distal (neighborhood) environmental correlates of adolescent obesity.

METHODS

This was a descriptive, cross-sectional study, using the 2007 National Survey of Children's Health, of 39,542 children aged 11-17 years. Structural equation modeling was used to test the fit of the model, identify direct and indirect effects of the proximal and distal environmental correlates, and determine reliabilities for latent constructs (Access to Physical Activity, Neighborhood Conditions, Social Capital Home Sedentary Behavior, and Physical Activity).

RESULTS

The model fitted the data well (Root Mean Square Standard Error of Approximation: .038 (90% confidence interval .038-.039), Comparative Fit Index: .950, and Tucker-Lewis Index: .934). Access to Physical Activity, Social Capital, Home Sedentary Behavior, and Physical Activity had direct effects on obesity (-.026, p = .001; .061, p < .001; .110, p < .001; and -.119, p < .001, respectively). Neighborhood Condition had indirect effects on obesity through Access to Physical Activity, Social Capital, and Home Sedentary Behavior (-.001, p = .009; .032, p < .001; and .044, p < .001, respectively). Access to Physical Activity had indirect effects on obesity through Physical Activity, Social Capital, and Home Sedentary Behavior (-.013, p < .001; -.005, p < .001; and -.005, p = .003, respectively). Home Sedentary Behavior had indirect effect on obesity through Physical Activity (.052, p <.001).

CONCLUSIONS

Results of this model fit to the U. S. population-based data suggest that interventions should target not only sedentary behavior and physical activity but also parent perceptions of safety, access to physical activity, and the neighborhood condition.

Behavioural support of a proposed neurocognitive connection between physical activity and improved eating behaviour in obese women

PROBLEM

An explanation of the association between physical activity and improved eating behaviours has recently been posited via the effect of physical activity on executive functions of the brain resulting in a reduction in the hedonic drive to overeat. Decomposition and clarification of embedded relationship through a behavioural/psychological framework was sought.

METHODS

Changes in theory-based psychosocial factors over 26 weeks were tested with 134 severely obese women (age 41.7±10.4 years) initiating a physical activity support treatment. Mediation and reciprocal effects analyses incorporating these changes were then computed.

RESULTS

Significant improvements in mood, self-regulation for eating, and self-efficacy for controlled eating were found. Emanating from mood change, a reciprocal relationship between changes in the self-regulation and self-efficacy measures was found. Thus, each factor reinforced the other's change.

CONCLUSION

Findings suggest a convergence of neurocognitively and behaviourally based explanations of the relations of physical activity and controlled eating. Implications for behavioural weight-loss theory and treatments were suggested.

Bi-Directional Relationship Between Self-Regulation and Improved Eating: Temporal Associations With Exercise, Reduced Fatigue, and Weight Loss

Severely obese men and women (body mass index ≥ 35 ≤ 55 kg/m(2); M(age) = 44.8 years, SD = 9.3) were randomly assigned to a 6-month physical activity support treatment paired with either nutrition education (n = 83) or cognitive-behavioral nutrition (n = 82) methods for weight loss. Both groups had significant improvements in physical activity, fatigue, self-regulation for eating, and fruit and vegetable intake. Compared to those in the nutrition education group, participants in the behavioral group demonstrated greater overall increases in fruit and vegetable intake and physical activity. These group differences were associated with changes that occurred after Month 3. Increased physical activity predicted reduced fatigue, β = -.19, p =.01. A reciprocal relationship between the mediators of that relationship, which were changes in self-regulation and fruit and vegetable intake, was identified. There was significantly greater weight loss over six months in the behavioral nutrition group when contrasted with the nutrition education group. Self-regulation for eating and fruit and vegetable intake were significant predictors of weight loss over both three and six months. Findings enabled a better understanding of psychosocial effects on temporal aspects of weight loss and may lead to more effective behavioral treatments for weight loss.

Reciprocal effects of treatment-induced increases in exercise and improved eating, and their psychosocial correlates, in obese adults seeking weight loss: a field-based trial

BACKGROUND

A better understanding of interrelations of exercise and improved eating, and their psychosocial correlates of self-efficacy, mood, and self-regulation, may be useful for the architecture of improved weight loss treatments. Theory-based research within field settings, with samples possessing high probabilities of health risks, might enable rapid application of useful findings.

METHODS

Adult volunteers with severe obesity (body mass index [BMI] 35-50 kg/m²; age = 43.0 ± 9.5 y; 83% female) were randomly assigned to six monthly cognitive-behavioral exercise support sessions paired with either group-based nutrition education (n = 145) or cognitive behavioral methods applied to improved eating (n = 149). After specification of mediation models using a bias-corrected bootstrapping procedure, a series of reciprocal effects analyses assessed: a) the reciprocal effects of changes in exercise and fruit and vegetable intake, resulting from the treatments, b) the reciprocal effects of changes in the three psychosocial variables tested (i.e. self-efficacy, mood, and self-regulation) and fruit and vegetable change, resulting from change in exercise volume, and c) the reciprocal effects of changes in the three psychosocial variables and exercise change, resulting from change in fruit and vegetable intake.

RESULTS

Mediation analyses suggested a reciprocal effect between changes in exercise volume and fruit and vegetable intake. After inclusion of psychosocial variables, also found were reciprocal effects between change in fruit and vegetable intake and change in mood, self-efficacy for controlled eating, and self-regulation for eating; and change in exercise volume and change in mood and exercise-related self-regulation.

CONCLUSION

Findings had implications for behavioral weight-loss theory and treatment. Specifically, results suggested that treatments should focus upon, and leverage, the transfer effects from each of the primary weight-loss behaviors (exercise and healthy eating) to the other. Findings on psychosocial correlates of these behavioral processes may also have practical applications.

Exercise Program-Induced Mood Improvement and Improved Eating in Severely Obese Adults

Background:

Using a practical setting, this study aimed to test exercise and nutrition interventions' effects on negative mood, self-regulation, and self-efficacy to control eating; and to assess the ability of mood change to predict changes in eating behavior, while accounting for changes in self-regulation and self-efficacy.

Methods:

Severely obese adults participated in a cognitive-behavioral exercise support treatment paired with either nutrition education ( n = 140) or cognitive-behavioral methods applied to improved eating ( n = 146). They were assessed on measures of overall negative mood, self-regulatory skill usage, self-efficacy to control eating when negative moods are present, and fruit and vegetable consumption at baseline and Week 26.

Results:

Significant improvements in each psychosocial variable and fruit and vegetable intake were found. Improved mood significantly predicted fruit and vegetable consumption change, R2 = 0.12, P < 0.001. Entry of changes in self-regulation and self-efficacy into the multiple regression equation significantly strengthened the variance explained, R2 = 0.18, P < 0.001.

Discussion:

Findings suggest that exercise-induced improvements in mood improve eating behaviors, with increases in self-regulation and self-efficacy adding to this effect.

Moderation of age, sex, and ethnicity on psychosocial predictors of increased exercise and improved eating

Although research indicates that treatment-induced improvements in self-regulation, mood, and self-efficacy significantly predict increased exercise and improved eating, moderation by participants' personal characteristics is largely unknown. Severely obese adults (N = 414; 47% White, 53% African American) volunteered for a behavioral exercise and nutrition treatment and demonstrated significant within-group improvements in self-efficacy for exercise, self-regulation for exercise, mood, self-efficacy for controlled eating, self-regulation for controlled eating, exercise volume, and fruit and vegetable intake over 26 weeks. After testing age, sex, and race/ethnicity as possible moderators of the prediction of changes in exercise volume and fruit and vegetable consumption by changes in self-regulation, mood, and self-efficacy, only age significantly moderated change in volume of exercise. Implications for theory and treatment were discussed.

What are the most effective techniques in changing obese individuals' physical activity self-efficacy and behaviour: a systematic review and meta-analysis

Increasing self-efficacy is generally considered to be an important mediator of the effects of physical activity interventions. A previous review identified which behaviour change techniques (BCTs) were associated with increases in self-efficacy and physical activity for healthy non-obese adults. The aim of the current review was to identify which BCTs increase the self-efficacy and physical activity behaviour of obese adults. A systematic search identified 61 comparisons with obese adults reporting changes in self-efficacy towards engaging in physical activity following interventions. Of those comparisons, 42 also reported changes in physical activity behaviour. All intervention descriptions were coded using Michie et al's (2011) 40 item CALO-RE taxonomy of BCTs. Meta-analysis was conducted with moderator analyses to examine the association between whether or not each BCT was included in interventions, and size of changes in both self-efficacy and physical activity behaviour. Overall, a small effect of the interventions was found on self-efficacy (d = 0.23, 95% confidence interval (CI): 0.16-0.29, p < 0.001) and a medium sized effect on physical activity behaviour (d = 0.50, 95% CI 0.38-0.63, p < 0.001). Four BCTs were significantly associated with positive changes in self-efficacy; 'action planning', 'time management', 'prompt self-monitoring of behavioural outcome' and 'plan social support/social change'. These latter two BCTs were also associated with positive changes in physical activity. An additional 19 BCTs were associated with positive changes in physical activity. The largest effects for physical activity were found where interventions contained 'teach to use prompts/cues', 'prompt practice' or 'prompt rewards contingent on effort or progress towards behaviour'. Overall, a non-significant relationship was found between change in self-efficacy and change in physical activity (Spearman's Rho = -0.18 p = 0.72). In summary, the majority of techniques increased physical activity behaviour, without having discernible effects on self-efficacy. Only two BCTs were associated with positive changes in both physical activity self-efficacy and behaviour. This is in contrast to the earlier review which found a strong relationship between changes in physical activity self-efficacy and behaviour. Mechanisms other than self-efficacy may be more important for increasing the physical activity of obese individuals compared with non-obese individuals.

Mediation of social cognitive theory variables in the relationship of exercise and improved eating in sedentary adults with severe obesity

Results from behavioral treatments for obesity have been disappointing due to an inability to sustain healthy eating. The concurrent use of theory, research, and practical application has the potential of reducing overeating through innovative treatments. When overweight individuals begin an exercise program their eating tends to improve, however, the basis of this relationship is not determined. If the psychosocial mediators of the relationship between exercise and improved eating are better understood, supported exercise may be a key component for improving the efficacy of behavioral weight management treatments. In Phase 1 of this research, psychosocial variables derived from social cognitive theory were tested as possible mediators of the relationship of exercise participation with increased fruit and vegetable intake in severely obese adults initiating a 26-week treatment of supported exercise and standard nutrition education (n = 161). Change in self-regulation for healthy eating and self-regulation at treatment end was a strong mediator; with the addition of mood and self-efficacy for healthy eating being additional mediators that notably increased effect ratios. In Phase 2, participants in a cognitive-behavioral nutrition treatment tailored to improve the identified mediators (n = 163) were contrasted with the original group. The cognitive-behavioral nutrition treatment was associated with significantly greater increases than standard nutrition education in self-regulation, p = 0.023, CIs [4.69, 6.48], and [3.19, 5.02], respectively; self-efficacy, p = 0.013, CIs [19.72, 29.41], and [11.70, 20.71], respectively; and a marginally significant decrease in negative mood, p = 0.062, CIs [-14.26, -9.36], and [-10.90, -6.45], respectively. Findings served to inform treatment designs concerning the use of supported exercise and cognitive-behavioral means to derive better outcomes related to nutrition and weight loss in individuals with severe obesity.

The association between physical activity and eating self-regulation in overweight and obese women

OBJECTIVE

Successful weight management relies heavily on eating and exercise behaviors. However, little is known about the association between both on a psychosocial level. This study examined the relationship between exercise and eating regulation by exploring the mediating effects of negative body image investment and depressive mood, and their stability through time.

METHODS

Analyses were conducted at two different moments (12 and 36 months), involving a sample of 221 overweight/obese women (age: 37.6 ± 7 years; BMI: 31.6 ± 4.1 kg/m(2)) that participated in a behavioral weight control intervention. Bivariate correlations and mediation analyses using Preacher & Hayes resampling procedures were conducted.

RESULTS

At 12 months, negative body image investment was the only significant mediator of the exercise-eating relationship. This variable explained larger portions of the indirect effects of structured rather than lifestyle exercise on eating. At 36 months, negative investment and to a lesser extent depressive mood partially explained the exercise-eating association.

CONCLUSIONS

Our findings suggest that, besides physiological effects of exercise, psychological mechanisms related to body image and mood also explain the role of physical activity as a 'gateway behavior' for improved eating regulation in overweight women. These effects appear to be stable and may help understand the key role of exercise in long-term weight management.

Supported exercise improves controlled eating and weight through its effects on psychosocial factors: extending a systematic research program toward treatment development

BACKGROUND

Behavioral weight-loss treatments have been overwhelmingly unsuccessful. Many inadequately address both behavioral theory and extant research--especially in regard to the lack of viability of simply educating individuals on improved eating and exercise behaviors.

OBJECTIVE

The aim was to synthesize research on associations of changes in exercise behaviors, psychosocial factors, eating behaviors, and weight; and then conduct further direct testing to inform the development of an improved treatment approach.

METHODS

A systematic program of health behavior-change research based on social cognitive theory, and extensions of that theory applied to exercise and weight loss, was first reviewed. Then, to extend this research toward treatment development and application, a field-based study of obese adults was conducted. Treatments incorporated a consistent component of cognitive-behaviorally supported exercise during 26 weeks that was paired with either standard nutrition education (n = 183) or cognitive-behavioral methods for controlled eating that emphasized self-regulatory methods such as goal setting and caloric tracking, cognitive restructuring, and eating cue awareness (n = 247).

RESULTS

Both treatment conditions were associated with improved self-efficacy, self-regulation, mood, exercise, fruit and vegetable consumption, weight, and waist circumference; with improvements in self-regulation for eating, fruit and vegetable consumption, weight, and waist circumference significantly greater in the cognitive-behavioral nutrition condition. Changes in exercise- and eating-related self-efficacy and self-regulation were associated with changes in exercise and eating (R(2) = 0.40 and 0.17, respectively), with mood change increasing the explanatory power to R(2) = 0.43 and 0.20. Improved self-efficacy and self-regulation for exercise carried over to self-efficacy and self-regulation for controlled eating (β= 0.53 and 0.68, respectively).

CONCLUSIONS

Development and longitudinal testing of a new and different approach to behavioral treatment for sustained weight loss that emphasizes exercise program-induced psychosocial changes preceding the facilitation of improved eating and weight loss should be guided by our present research.