[Temporal trend of physical activity in Brazilian adolescents: analysis of the Brazilian National Survey of School Health from 2009 to 2019].

This study aimed to analyze the physical activity trend of Brazilian schoolchildren and the associations with demographic, socioeconomic, and behavioral variables by using the Brazilian National Survey of School Health (PeNSE) in its four editions - 2009, 2012, 2015, and 2019. Data from students (13-17 years old) participating in the four editions of the PeNSE (n = 392,922) were used. We describe the percentage of active, mean, and percentile values of moderate to vigorous intensity physical activity in minutes/week. Poisson's regression was adjusted for gender, age, skin color, goods score, and sedentary behavior (≥ 2 hours/day watching TV and ≥ 3 hours/day sitting time). As a limitation, the PeNSE/2009 sample refers only to the Brazilian capital cities. The percentage of active students decreased from 43.1% in 2009 to 18.2% in 2019. The mean moderate to vigorous intensity physical activity of PeNSE/2009 (mean = 318.4 minutes/week; 95%CI: 313.4-323.4) decreased 50% in 2019. In physical education, the weekly average in moderate to vigorous intensity physical activity of girls is less than 50 minutes and boys is greater than 60 minutes in the four editions of PeNSE, also 22.7% of girls reported (PeNSE/2019) not having taken physical education classes whereas the same thing is reported by 19.7% of boys. Sedentary behavior reduced regarding time watching TV, but sitting time increased by 50.1% (95%CI: 48.9-51.3) and 54% (95%CI: 53.1-54.9) between PeNSE/2009 and PeNSE/2019. As a consequence of the drop in physical activity levels, public policies that promote physical activity are necessary, including increasing physical education classes at school to at least three times a week.