The Role of Social Support vs. Modeling on Adolescents' Diet and Physical Activity: Findings from a School-based Weight Management Trial.

Objective: Social influences play an important role in shaping adolescents' dietary and physical activity behaviors. We examined the role of perceived modeling and perceived social support from family and friends on diet and physical activity behaviors among overweight and obese adolescents participating in a weight management trial.

Methods: Six high schools were randomized to a school-nurse delivered behavioral weight management intervention or an information attention-control. Data on perceived support and modeling of healthy eating and physical activity from family and friends and dietary and physical activity behaviors were obtained from participants (N=82) at baseline and 2- and 6-months follow-up.

Results: Linear mixed models were used to examine associations between social factors at baseline and diet and physical behaviors at 6 months. Friend support was correlated with increased fruit and vegetable consumption (0.4 servings/day) and decreased added sugar intake (-14.2 grams/day) (p's<0.05). Family support for physical activity, friend support for physical activity, and family modeling of physical activity were associated with increased number of days/week active for ≥ 60 minutes/day (0.7 days/week; 0.6 days/week; and 0.4 days/week, respectively, p's<0.05).

Conclusions: Among overweight and obese high school adolescents, support from family and friends was associated with a greater number of improvements in diet and physical activity at follow-up than modeling. Strategies to solicit support may maximize efficacy of adolescent obesity intervention efforts.