[Physical activity and sedentary behavior among adolescent high school students].

OBJECTIVE To identify the prevalence of factors associated with insufficient physical activity levels and sedentary behavior among adolescents. METHODS In this cross-sectional study 4,210 students (14-19 years old) attending public high-schools were selected using random two-stage cluster sampling. Data were collected by using the Global School-based Student Health Survey. Subjects who reported performing 60 minutes or more of moderate to vigorous physical activity five days a week or more were classified as physically active, while the remainder was classified as insufficiently active. Subjects who reported watching TV three or more hours a day were considered to be exposed to sedentary behavior. Analyses were carried out by using Chi-square tests and binary logistic regression. RESULTS The prevalence of insufficiently active subjects was 65.1% (CI95% 63.7-66.6). Gender, place of residence (rural/urban), time of day attending school, occupational status, and enrollment in physical education were identified as factors significantly associated with exposure to insufficient levels of physical activity. Prevalence of exposure to sedentary behavior was 40.9% (CI95% 39.4-42.4) on week days and 49.9% (CI95% 48.4-51.4) on weekend days. Place of residence, time of day attending school, occupational status and enrollment in physical education were identified as factors significantly associated with exposure to sedentary behavior on week days, whereas on weekend days exposure to sedentary behavior was related to gender, age and time of day attending school. CONCLUSION This study showed a high prevalence of insufficient physical activity levels and exposure to sedentary behaviors among adolescents.