Relationship of physical activity to eating behaviors and weight loss in women

Purpose: To examine whether change in physical activity is associated with compliance to changes in dietary intake and eating behaviors in an 18-month behavioral weight loss program, and to examine the contribution of exercise to weight loss when these other weight loss behaviors are also considered. Methods: Data from 104 subjects who completed an 18-month behavioral weight loss program were analyzed in this study. All subjects were prescribed a reduced energy (1200-1500 kcal(.)d(-1)) and fat (20 to 30%) diet, and exercise progressed from 100 to 200 min(.)wk(-1). Subjects attended group behavioral lessons throughout the study. Weight, physical activity, energy intake, and weight loss eating behaviors were assessed at 0 and 18 months. Results: Body weight decreased 7.8 +/- 7.5 kg and body mass index decreased 2.8 +/- 2.7 kg(.)m(-2) from 0 to 18 months (P < 0.05). Total energy intake (kcal(.)d(-1)) and macronutrient intake (g(.)d(-1)) decreased, whereas physical activity and eating behaviors associated with weight loss increased from 0 to 18 months (P < 0.05). Change in physical activity was significantly correlated with weight loss (r = 0.33), reductions in energy intake (r = 0.20), and improvements in eating behaviors associated with weight loss (r = 0.24) (P < 0.05). Regression analysis indicated that change in physical activity significantly improved weight loss after changes in energy intake and weight loss eating behaviors were considered in the analysis, with R 2 significantly improving by approximately 0.04 (P < 0.05). However, results from multiple regression showed weight loss was influence more by changes in eating behaviors than changes in physical activity (R-2 = 0.17 vs R-2 = 0.04). Conclusions: The combination of changes in eating and physical activity behaviors can improve long-term weight loss compared with either behavior alone. Interventions targeting both behaviors are recommended for improving long-term weight loss.