Personal, behavioral, and socio-environmental correlates of physical activity among adolescent girls: cross-sectional and longitudinal associations.

BACKGROUND Physical activity (PA) declines sharply and rapidly during adolescence, especially among girls, posing a risk for inactivity and obesity in adulthood. This study identified personal, behavioral, and socioenvironmental correlates of concurrent and 6-month longitudinal PA among adolescent girls. METHODS Data were gathered from 356 adolescent girls (mean age 15.8 ± 1.2 years; > 75% racial/ethnic minorities) in the Minneapolis/St. Paul area in 2007-2009. Linear regression analyses controlling for age, race/ethnicity, and school were conducted predicting baseline and follow-up levels of total PA and moderate-to-vigorous PA (MVPA) assessed via 3-Day Physical Activity Recall. Models were fit for each correlate individually and for all correlates together, mutually adjusted. RESULTS For concurrent PA, significant positive predictors when adjusting for the influence of all other variables included self-efficacy, support from friends and teachers, and friends' PA. Total screen time and distance from school to PA resources related inversely to concurrent PA. In mutually-adjusted models, 6-month PA was positively related to self-worth, family support, and parent PA and inversely related to total screen time. CONCLUSIONS PA interventions with adolescent girls might be enhanced by involving adolescents' social networks and also by helping adolescents feel better about their self-worth and athletic abilities.