Time Trends in Overall Daily Physical Activity and Cardiovascular Disease Risk Factors by Organized Physical Activity Participation in Adolescent Girls

Title of Document: TIME TRENDS IN OVERALL DAILY PHYSICAL ACTIVITY AND CARDIOVASCULAR DISEASE RISK FACTORS BY ORGANIZED PHYSICAL ACTIVITY PARTICIPATION IN ADOLESCENT GIRLS. Jennifer Ann Phillips, MS, 2009 Directed By: Professor Deborah Rohm Young Epidemiology and Biostatistics, Kinesiology Many youth are involved in organized physical activity (PA); however, the impact of these activities on daily PA, body fat, and cardiovascular disease (CVD) risk factors is not well understood. Purpose: To compare the overall daily PA and CVD risk factors of girls who participate in organized activities to non-participants throughout adolescence. Methods: Data from the National Heart, Lung, and Blood Institute Growth and Health Study, a 10-year observational study of Black and White girls (N=2379), were analyzed. Organized PA was defined as participation in classes/lessons and sports (0, <4, 4-19.99, ≥20 MET times/wk). Outcomes included daily PA (3-day diary), body fat (bioelectrical impedance analysis), lipids, glucose, insulin, and blood pressure. Longitudinal data were examined for each outcome using a mixed model with repeated measures. Girls were also categorized by the number of years they reported ≥4 MET times/wk of organized PA. Outcomes and risk clustering at 18-19y were evaluated with ANOVA and logistic regression, respectively, by number of participation years. Results: Organized PA and participation*time*race were related to change in daily PA and body fat (p < 0.0001). Although daily PA declined for Black girls, those with ≥20 MET times/wk had higher PA levels than all other girls (p < 0.0001). Change differed by sports participation in White girls (p=0.019); those involved ≥20 MET times/wk demonstrated better maintenance of daily PA. Black girls with ≥20 MET times/wk had significantly lower body fat than nonparticipants (p=0.002).White non-participants had higher body fat than those with 419.99 MET times/wk (p=0.006). Accumulated organized PA was related to daily PA and body fat at 18-19y. Girls who never reported participation had significantly lower daily PA at 18-19y than all other groups (p < 0.02), and significantly higher body fat at 18-19y compared to girls who reported 4y of sports participation (p=0.038). Organized PA was not related to change in other CVD risk factors or risk factor clustering at 18-19y (OR=1.05, 95% CI=0.87-1.27, p=0.59). Conclusion: Organized PA was related to daily PA and body fat for Black and White girls throughout adolescence. Appealing options should be made available and participation encouraged. TIME TRENDS IN OVERALL DAILY PHYSICAL ACTIVITY AND CARDIOVASCULAR DISEASE RISK FACTORS BY ORGANIZED PHYSICAL ACTIVITY PARTICIPATION IN ADOLESCENT GIRLS.