School and individual-level correlates of physical activity in children: a multilevel approach

Resumen

This study aimed to assess the association between individual and school environment variables and physical activity levels in Brazilian schoolchildren with 8-12 years of age.  A sample of children from 20 private and public schools (n=1,210) was selected. Total and leisure-time physical activities and active transportation to school (AT) were measured using a self-report instrument. Total and leisure-time physical inactivity (PI) were defined as <300min/week of Physical activity. Physical and social school environment features were assessed through a questionnaire. The prevalence of PI, leisure-time PI, and AT to school were 69.2%, 75.8% and 70.5%, respectively. Multilevel models showed that PI was more frequent among girls, and was negatively associated with older age and higher maternal schooling. Girls were more inactive during leisure-time. For contextual variables, greater Physical Education teacher/student ratio was associated with lower levels of both total and leisure-time PI. AT was negatively associated with higher income and positively associated with older age. Students from public schools use more AT. Based on the prevalence of PI found, strategies focused at increasing physical activity levels should be implemented immediately. Also, our findings suggest that both individual and school contextual variables were associated with levels of PI, varying between domains.