JAKICIC, J. M., R. R. WING, and C. WINTERS-HART. Relationship of physical activity to eating behaviors and weight loss in women. Med. Sci. Sports Exerc., Vol. 34, No. 10, pp. 1653–1659, 2002.
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 R2 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 (R2 = 0.17 vs R2 = 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.