Prevalence of physical inactivity and associated factors among adolescents from public schools in Uruguaiana, Rio Grande do Sul State, Brazil.

This study aimed to identify the prevalence of physical inactivity and associated factors in adolescents, using a cross-sectional design with a sample of 1,455 adolescents (741 females). Data were collected using a questionnaire consisting of socio-demographic, perceptual, and behavioral variables. Physical activity was estimated with the Physical Activity Questionnaire for Older Children and Adolescents. Prevalence of physical inactivity was 68% (95%CI: 65.6%-70.4%). The following variables remained associated with physical inactivity in the adjusted analysis (p < 0.05): living in an apartment, female gender, older adolescents, lower self-rated physical activity compared to peers, low perception of maternal physical activity, passive commuting to school, non-participation in physical education at school, non-enjoyment of physical education classes, and limited involvement in other types of physical exercise besides physical education at school. There were a high proportion of inactive adolescents. Strategies to prevent physical inactivity in adolescents should be elaborated with a central role for the school and family.