Changes in Self-efficacy for Exercise and Improved Nutrition Fostered by Increased Self-regulation Among Adults with Obesity

James J. Annesi, Kennesaw State University
Ping H. Johnson, Kennesaw State University
Kristin L. McEwen, YMCA of Metropolitan Atlanta

Abstract

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/m2) 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.