LAUSR

BACKGROUND Regular physical activity and doing well in school are important for growing adolescents. In this study, the associations between physical activity and perceived school performance (PSP) are examined together. METHODS Young adolescents from 42 countries (n = 193,949) in Europe and Canada were examined for associations between self-reported moderate to vigorous physical activity (MVPA) and PSP. Multinominal analyses were conducted with 0 to 2 days of MVPA and below average PSP as reference categories. Adjusted odds ratios and 95% confidence intervals were reported for pooled data and individual countries after controlling for family affluence scale. RESULTS Girls had better PSP than boys, yet more boys participated in daily MVPA than girls. The associations between PSP and MVPA were inverted U shaped. The strongest association for very good PSP was among young adolescents who reported 5 to 6 days MVPA (odds ratios = 2.3; 95% confidence interval, 2.1-2.4) after controlling for family affluence scale. CONCLUSIONS Young adolescents with average or better PSP took part in at least 3 days of MVPA in a week, suggesting that participating in some MVPA was positively associated with PSP. More days of MVPA in a week, especially for young adolescents with below average PSP, would be beneficial for health and school performance.