Generalization of theory-based predictions for improved nutrition to adults with morbid obesity: Implications of initiating exercise

Exercise is a robust predictor of long-term success with weight loss, and research based on social cognitive theory suggests that exercise program-induced changes in self-regulation, mood, and self-efficacy transfer to improved eating. These relationships were tested in adults with morbid obesity (overall M_age = 43 years; 86% female; M_{body mass index} = 45 kg/m²) participating in a 6-month treatment of cognitive-behaviorally supported exercise paired with either standard nutrition education (n = 87) or cognitive-behavioral methods for controlled eating (n = 89). Based on multiple mediation analyses, improvements in self-regulation and self-efficacy were significantly associated with increased fruit and vegetable intake and reduced body mass index (BMI). The cognitive-behavioral nutrition methods were associated with greater improvements in fruit and vegetable intake and BMI, however, within both models, complete mediation was found after simultaneous entry of changes in self-regulation, mood, and self-efficacy, and exercise volume as mediators. Only the indirect effect of change in self-regulation was a significant (or marginally significant) independent mediator. Generalization of previously identified relationships between exercise program-induced improvements in psychosocial variables and improvements in nutrition and BMI were supported for individuals with morbid obesity. Based on these relationships, implications for behavioral treatments were discussed.     

Relationships between self-regulation skills and physical activity and fruit and vegetable consumption in obese adults: mediation of mood and self-efficacy

In cognitive-behavioral treatments for obesity, self-regulation is thought to be a strong predictor of behavioral change, but it is rarely directly measured in intervention research. Thus, how self-regulation interacts with other psychological variables regarding treatment effects is largely unknown. In this preliminary field study, self-regulatory skills were directly measured and were found to be significantly associated with both volume of exercise and fruit and vegetable consumption in severely obese adults (N=116) enrolled in a behavioral weight management program. Significant partial and complete mediation of the relationship between self-regulation for physical activity and physical activity, and self-regulation for appropriate eating and fruit and vegetable intake, respectively, were found by reported negative mood. Self-efficacy was not found to be a significant mediator of these relationships. The bivariate relationship between baseline scores of self-regulation for physical activity and self-regulation for appropriate eating was significant (r = .46), which supported the premise that self-regulation is a trait-like personal characteristic. Volume of exercise and fruit and vegetable consumption significantly predicted weight loss over 6 months (R2 = .35). Results were consistent with the few laboratory-based findings available and, after replication, may extend theory related to obesity treatment.     

Predicting 2-year weight loss through temporally specific earlier losses,relevant behaviors,and their psychological correlates: Implications for behavioral treatment architectures

Maintaining loss of weight beyond an initial 6–9 months remains problematic, with research indicating little recent progress. A poor understanding of how and when prior weight loss, behavioral changes, and psychosocial predictors are associated with long-term weight changes persists. To better-inform behavioral treatments for long-term success with weight loss, women with obesity (N = 86; M_age = 48.6 years) volunteered for research incorporating community-based weight-management treatments. They were assessed at months 6, 12, and 24 on theory-based psychosocial and behavioral factors, and over 24 months on weight. Considering the included times and temporal ranges, it was found that change in weight from month 6–24 was the strongest predictor of 24-month weight change, and physical activity and fruit/vegetable intake at month 24 best predicted that change in weight. Self-regulation, self-efficacy, and mood at month 24 best predicted both physical activity and fruit/vegetable intake at month 24, with body satisfaction also a significant predictor of physical activity. From these data, mediation analyses found that the predictions of long-term weight loss by scores of self-regulation, self-efficacy, body satisfaction, and mood at month 24 were significantly mediated by fruit/vegetable intake and physical activity in separate equations. Findings indicated both psychosocial and behavioral targets, and timing for those targets, most indicative of long-term success with weight loss.     

Self-regulation foci and mood affect healthy and unhealthy eating behaviours differently in successful weight-loss treatment participants

An increased understanding of how self-regulation and mood affects both healthy and unhealthy eating behaviours is required to improve weight-loss intervention architectures. Women with obesity (N = 54, M_BMI = 34.80 kg/m²), who obtained ≥5% weight loss over 12 months (M = −9.01 kg) within a community-based behavioural weight-loss treatment, were assessed. Improvements in exercise- and eating-focused self-regulation (over 3 and 6 months), and the consumption of fruits/vegetables and sweets (over 6 and 12 months), were each significant. Multiple regression analyses indicated that changes in (a) aggregated (exercise-focused + eating-focused) self-regulation, (b) eating-focused self-regulation alone and (c) eating self-regulation that carried over from exercise-focused self-regulation, each significantly predicted fruit/vegetable consumption changes (R² = .15–.28). Entry of overall mood did not significantly increase those models' predictive strength. Conversely, mood was the most salient predictor of change in sweets intake. There were significant inverse relationships between changes in fruits/vegetables and sweets consumption. Implications for self-regulation theory and treatment improvements were suggested.     

Mediation of self‐regulation and mood in the relationship of changes in high emotional eating and nutritional behaviors: Moderating effects of physical activity

High emotional eating (EE) is prevalent in women with obesity. A previous study's subsample of obese women classified as high emotional eaters participated in either a physical activity‐focused experimental (n = 29) or an educationally focused comparison (n = 22) behavioral treatment and was assessed over phases of expected weight loss (baseline–month 6) and short‐ and long‐term regain (months 6–12 and 6–24, respectively). The study's aim was to assess theory‐based psychological and behavioral mediation and moderation of changes in nutritional behaviors via emotional eating change in order to inform behavioral weight‐loss treatments. During the weight‐loss phase, significant improvements in eating self‐regulation and mood significantly mediated the relationship of reduced EE and intake of both fruits and vegetables (FV) and sweets. Self‐regulation was a significant independent mediator. Physical activity significantly moderated the relationship between EE and self‐regulation changes. All variables demonstrated large positive effects and significant time × group interactions favoring the experimental group. During the short and long‐term phases of expected weight regain, there were no significant changes in FV intake, although consumption of sweets significantly increased during months 6–24. Change in FV and sweets significantly predicted weight change, which was significantly greater in the experimental vs. comparison group over both the initial 6 months (?6.1% vs. ?2.6%) and full 24 months of the study (?7.6% vs. ?1.3%). Findings suggest that behavioral treatments should address EE through improvements in self‐regulation and mood, and supported physical activity will aid in that process. The need for an improved understanding of weight‐loss maintenance remains.     

Challenging body weight: evidence from a community-based intervention on weight,behaviour and motivation

The objective of this study was to examine the effectiveness of a 12 week weight loss intervention within a commercial fitness centre on body weight, moderate to vigorous physical activity (MVPA), dietary intake, and behavioural regulations for exercise and healthy eating. Using a quasi-experimental design, the intervention group received weekly coaching sessions and bi-weekly seminars designed to increase MVPA and improve dietary intake. Outcome variables were assessed at three time points over a six month period. Results showed a significant interaction for body weight (p = .04) and dietary changes (p < .05) following the weight loss challenge but were not maintained across the six month period. Changes in behavioural regulations favoured the intervention condition. Results imply that a 12 week weight loss challenge within a commercial fitness centre may be effective at prompting short-term weight loss and support the internalization of behavioural regulations specific to healthy eating and exercise.     

Psychological and social predictors of changes in fruit and vegetable consumption over 12 months following behavioral and nutrition education counseling.

This study assessed psychological and social factors predicting 12-month changes in fruit and vegetable consumption achieved by 271 men and women from a low-income population randomized to brief behavioral and nutrition education counseling. Greater increases in fruit and vegetable intake were achieved in the behavioral than in the nutrition education condition (1.49 vs. 0.87 portions per day, p=.021). Increases were predicted by baseline social support for dietary change but not by baseline psychological measures. However, short-term (8-week) changes in dietary self-efficacy, encouragement, anticipated regret, perceived benefits, and knowledge of recommended intake predicted 12-month changes in fruit and vegetable consumption independently of gender, age, ethnicity, income, and baseline intake. These factors accounted for 51% of the superiority of behavioral counseling over nutrition education.     

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

Physical activity may affect weight loss largely through psychological pathways associated with eating changes, especially in obese individuals whose caloric expenditure through exercise is typically small. Direct testing of this is, however, lacking. Previously sedentary adults (N?=?114; 77% female; M _age?=?43.3 years), with a minimum body mass index (BMI) of 35?kg/m² (M _BMI?=?42.0?kg/m²), participated in a 24-week treatment of cognitive-behavioural exercise support and nutrition information. A path model based on tenets of social cognitive and self-efficacy theory was constructed. It was expected that improvements in self-efficacy, physical self-concept, body satisfaction and mood associated with the exercise treatment would predict changes in self-regulation and increased physical activity. It was also hypothesised that improvements in self-efficacy and self-regulation for appropriate eating would transfer from these relationships and predict weight loss. After three theoretically viable paths were added based on modification indices, structural equation modelling indicated a good fit with the data, χ ²(16)?=?20.53, p?=?0.20; RMSEA?=?0.05; SRMR?=?0.06; CFI?=?0.97; TLI?=?0.95. Associations of psychological effects linked to exercise programme participation with predictors of appropriate eating and weight loss were found, and may inform theory, research and treatments.     

Genetic causal beliefs about obesity,self-efficacy for weight control,and obesity-related behaviours in a middle-aged female cohort

Objective: Obesity is a heritable condition with well-established risk-reducing behaviours. Studies have shown that beliefs about the causes of obesity are associated with diet and exercise behaviour. Identifying mechanisms linking causal beliefs and behaviours is important for obesity prevention and control.

Design: Cross-sectional multi-level regression analyses of self-efficacy for weight control as a possible mediator of obesity attributions (diet, physical activity, genetic) and preventive behaviours in 487 non-Hispanic White women from South King County, Washington.

Main Outcome Measures: Self-reported daily fruit and vegetable intake and weekly leisure-time physical activity.

Results: Diet causal beliefs were positively associated with fruit and vegetable intake, with self-efficacy for weight control partially accounting for this association. Self-efficacy for weight control also indirectly linked physical activity attributions and physical activity behaviour. Relationships between genetic causal beliefs, self-efficacy for weight control, and obesity-related behaviours differed by obesity status. Self-efficacy for weight control contributed to negative associations between genetic causal attributions and obesity-related behaviours in non-obese, but not obese, women.

Conclusion: Self-efficacy is an important construct to include in studies of genetic causal beliefs and behavioural self-regulation. Theoretical and longitudinal work is needed to clarify the causal nature of these relationships and other mediating and moderating factors.     

Overvaluation of shape and weight among overweight children and adolescents with loss of control eating

Little is known about the phenomenology of pediatric loss of control (LOC) eating. Overvaluation of shape and weight, however, appears to be diagnostically meaningful among binge eating adults. We explored the significance of shape and weight overvaluation among children and adolescents with LOC eating. Participants (n = 526) included 149 overweight youth with LOC eating and 377 overweight controls (CON). Participants were categorized as those reporting at least moderate overvaluation (LOC-Mod, n = 74; CON-Mod, n = 106) or less than moderate overvaluation (LOC-Low, n = 75; CON-Low, n = 271), and compared on measures of eating-related and general psychopathology. LOC-Mod evidenced lower self-esteem than CON-Low, and greater behavioral problems than CON-Mod and CON-Low, but did not differ from LOC-Low in these domains. With the exception of LOC-Low and CON-Mod, all groups differed on global eating-disorder severity, with LOC-Mod scoring the highest. Overvaluation of shape and weight appears to be of questionable importance in defining subtypes of youth with LOC eating. However, as overvaluation and LOC eating each independently predicts eating-disorder onset, their confluence may confer even further risk for eating-disorder development. Longitudinal studies should address this possibility. Developmentally appropriate discussion about body image disturbance may be indicated in interventions targeting pediatric LOC eating and/or obesity.     

Effect of a behavioral intervention on dimensions of self-regulation and physical activity among overweight and obese adults with type 2 diabetes: a pilot study

The purpose of this pilot study was to determine the preliminary effect of a behavioral intervention on the use of self-regulation strategies and moderate-to-vigorous physical activity (MVPA) in overweight and obese adults with type 2 diabetes. 23 individuals recruited from ResearchMatc.org and campus advertisements were randomized into an intervention (n = 12) and control (n = 11) group. The intervention group received a behavioral intervention that used goal setting, time management, and self-monitoring to target dimensions of self-regulation and MVPA. The control received information regarding their PA habits. MVPA was measured via BodyMedia Armbands at pre- and post-test. The use of self-regulatory strategies for MVPA was assessed at pretest and posttest using the Self-Regulation for Exercise Scale. Cohen’s d effect sizes were calculated to determine the practical impact of the intervention. The intervention had a large effect on all dimensions of self-regulation across time: including total self-regulation (3.15), self-monitoring (4.63), goal setting (3.17), social support (1.29), self-reward (1.98), time management (4.41), and overcoming barriers (2.25). The intervention had no impact on dimensions of MVPA across time. This pilot study demonstrated the ability of a behavioral intervention to improve the use of self-regulation strategies for MVPA in a sample of adults with type 2 diabetes. These findings can further inform the development of health promotion programs to promote self-regulation. Future research should focus on determining ability of improvements in self-regulation to stimulate behavior change.     

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

Physical activity may affect weight loss largely through psychological pathways associated with eating changes, especially in obese individuals whose caloric expenditure through exercise is typically small. Direct testing of this is, however, lacking. Previously sedentary adults (N?=?114; 77% female; M(age)?=?43.3 years), with a minimum body mass index (BMI) of 35 kg/m2 (M (BMI)?=?42.0 kg/m2), participated in a 24-week treatment of cognitive-behavioural exercise support and nutrition information. A path model based on tenets of social cognitive and self-efficacy theory was constructed. It was expected that improvements in self-efficacy, physical self-concept, body satisfaction and mood associated with the exercise treatment would predict changes in self-regulation and increased physical activity. It was also hypothesised that improvements in self-efficacy and self-regulation for appropriate eating would transfer from these relationships and predict weight loss. After three theoretically viable paths were added based on modification indices, structural equation modelling indicated a good fit with the data, χ2(16)?=?20.53, p?=?0.20; RMSEA?=?0.05; SRMR?=?0.06; CFI?=?0.97; TLI?=?0.95. Associations of psychological effects linked to exercise programme participation with predictors of appropriate eating and weight loss were found, and may inform theory, research and treatments.     

N-of-1 study of weight loss maintenance assessing predictors of physical activity,adherence to weight loss plan and weight change

Objective: Behaviour change interventions are effective in supporting individuals to achieve clinically significant weight loss, but weight loss maintenance (WLM) is less often attained. This study examined predictive variables associated with WLM.

Design: N-of-1 study with daily ecological momentary assessment combined with objective measurement of weight and physical activity, collected with wireless devices (Fitbit?) for six months. Eight previously obese adults who had lost over 5% of their body weight in the past year took part. Data were analysed using time series methods.

Main outcomes measures: Predictor variables were based on five theoretical themes: maintenance motives, self-regulation, personal resources, habits, and environmental influences. Dependent variables were: objectively estimated step count and weight, and self-reported WLM plan adherence.

Results: For all participants, daily fluctuations in self-reported adherence to their WLM plan were significantly associated with most of the explanatory variables, including maintenance motivation and satisfaction with outcomes, self-regulation, habit, and stable environment. Personal resources were not a consistent predictor of plan adherence.

Conclusion: This is the first study to assess theoretical predictions of WLM within individuals. WLM is a dynamic process including the interplay of motivation, self-regulation, habit, resources, and perceptions of environmental context. Individuals maintaining their weight have unique psychological profiles which could be accounted for in interventions.     

An Open Trial of an Acceptance-Based Behavioral Intervention for Weight Loss

Innovative approaches are urgently needed to improve behavioral treatment for weight loss. The weight regain that is so common after treatment may be a result of an environment that makes it challenging to adhere, long-term, to a dietary and physical activity regimen. This study was designed to test, via a 12-week open trial, the preliminary feasibility, acceptability, effectiveness, and possible mechanisms of action of a behavioral treatment that was modified to incorporate acceptance-based therapy components designed to (a) bolster participants’ commitment to behavior change, (b) build distress-tolerance skills, and (c) promote mindful awareness of eating behaviors and goals. Participants (n = 29) were overweight or obese women. Among completers (n = 19; 34% attrition), weight loss averaged 6.6% of body weight at posttreatment and 9.6% at 6-month follow-up (n = 14; 52% attrition). Intention-to-treat weight losses were 4.5% at posttreatment and 6.6% at 6-month follow-up. Psychological variables targeted by the intervention (e.g., cognitive restraint, disinhibition, urge-related eating behavior, emotional eating, eating-related experiential acceptance, mindfulness and motivation) changed in the expected directions, and many of these changes were consistent with decreases in weight loss. Moreover, despite the limitations of the single-group design, this pilot study demonstrated the preliminary feasibility, acceptability, and effectiveness of a novel, acceptance-based behavioral treatment for obesity. One potential implication is that behaviorally based weight loss interventions might be improved by overlaying an acceptance-based framework.     

Defining recovery from an eating disorder: Conceptualization, validation, and examination of psychosocial functioning and psychiatric comorbidity

Conceptually, eating disorder recovery should include physical, behavioral, and psychological components, but such a comprehensive approach has not been consistently employed. Guided by theory and recent recovery research, we identified a “fully recovered” group (n = 20) based on physical (body mass index), behavioral (absence of eating disorder behaviors), and psychological (Eating Disorder Examination-Questionnaire) indices, and compared them with groups of partially recovered (n = 15), active eating disorder (n = 53), and healthy controls (n = 67). The fully recovered group was indistinguishable from controls on all eating disorder-related measures used, while the partially recovered group was less disordered than the active eating disorder group on some measures, but not on body image. Regarding psychosocial functioning, both the fully and partially recovered groups had psychosocial functioning similar to the controls, but there was a pattern of more of the partially recovered group reporting eating disorder aspects interfering with functioning. Regarding other psychopathology, the fully recovered group was no more likely than the controls to experience current Axis I pathology, but they did have elevated rates of current anxiety disorder. Results suggest that a stringent definition of recovery from an eating disorder is meaningful. Clinical implications and future directions regarding defining eating disorder recovery are discussed.     

Weight Bias Internalization and Psychosocial,Physical, and Behavioral Health: A Meta-Analysis of Cross-Sectional and Prospective Associations

Coinciding with widespread efforts to address obesity, weight bias internalization (a process of self-devaluation wherein individuals apply weight-biased stereotypes to themselves) has gained increased attention as a robust correlate of poor health outcomes. The present meta-analysis aimed to provide the largest quantitative synthesis of associations between weight bias internalization and health-related correlates. Studies that provided zero-order correlations for cross-sectional or prospective associations between weight bias internalization and physical, psychosocial, and behavioral health correlates were included in the meta-analysis. Meta-regression determined whether these associations differed based on demographic (sex/gender, race, age), anthropometric (body mass index), and study-level (publication status, sample type, study quality) moderators. Data for 149 (sub)samples were identified that included between 14 and 18,766 participants (M sample size = 534.96, SD = 1,914.43; M age = 34.73, SD = 12.61, range = 9.95–65.70). Results indicated that greater weight bias internalization was concurrently associated with worse psychosocial (e.g., negative and positive mental health, social functioning), physical (e.g., BMI, weight maintenance, health-related quality of life [HRQoL]), and behavioral health (e.g., disordered eating behaviors, healthy eating, physical activity) across most constructs, with effects ranging from small to very large in magnitude. Preliminary evidence also suggested that greater weight bias internalization was subsequently associated with less weight loss and increased negative mental health. Notable variations in the nature and magnitude of these associations were identified based on the health-related correlate and moderator under consideration. These findings indicate that weight bias internalization is linked to multiple adverse health-related outcomes and provide insight into priorities for future research, theory building, and interventions in this area.     

Executive Cognitive Function as a Correlate and Predictor of Child Food Intake and Physical Activity

Investigated were relations among executive cognitive function (ECF), food intake, and physical activity in 184, fourth grade children. It was hypothesized that self-reported ECF proficiency would predict greater self-reported fruit/vegetable intake and physical activity, but less “snack food” intake. Structural models demonstrated that ECF was significantly correlated with less concurrent snack food intake and greater concurrent fruit/vegetable intake, but not physical activity. Baseline ECF also significantly predicted greater fruit/vegetable intake and physical activity four months later, but not snack food intake. One implication is to promote ECF as a correlate and predictor of food intake and physical activity in children by providing opportunities for youth to practice newly developing ECF capacities.     

The impact of self-efficacy and implementation intentions-based interventions on fruit and vegetable intake among adults

This study tested the effect of interventions designed for people who do not eat yet the recommended daily fruit and vegetable intake (FVI) but have a positive intention to do so. Adults (N?=?163) aged 20–65 were randomised into four groups: implementation intentions (II group), self-efficacy (SE group), combination of II?+?SE group) and a control group receiving written information on nutrition. Study variables were measured at baseline, post-intervention and at 3-month follow-up. At follow-up, compared to the control group, FVI increased significantly in the II and II?+?SE groups (1.5 and 1.9 servings per day, respectively). Most psychosocial variables significantly increased compared to the control group, with the exception of SE for vegetable intake (VI). Moreover, at 3-month follow-up, change in FVI was mediated by changes in fruit intake (FI) intention and VI action planning. In conclusion, II interventions were efficient to increase FVI, with or without consideration for the development of SE. Thus, future studies should favour the adoption of this approach to bridge the intention–behaviour gap for FVI.     

Construing action abstractly and experiencing autonomy: Implications for physical activity and diet

Mentally representing action in terms of abstract goals rather than concrete procedures has been found to facilitate self-regulation, including meeting health goals. The present research examined whether autonomous motivation mediates the association between abstract thinking and health behavior engagement. We hypothesized that abstract (vs. concrete) thinking relates to viewing oneself as behaving autonomously, which, in turn, is positively associated with engaging in health behaviors. Two studies tested whether abstract thinking is associated with greater health behavior engagement and whether autonomous motivation statistically mediates this association. In Study 1, abstract thinking was associated positively with physical activity and fruit and vegetable intake. In Study 2, supporting pre-registered hypotheses, there was a significant indirect effect of abstract thinking on vigorous physical activity and fruit and vegetable intake through autonomous motivation. Whereas past research has emphasized that abstract thinking orients attention towards the value of broader goals, this research establishes that autonomous motivation helps explain associations between abstract thinking and health behavior engagement.