Effects of a School-Based Physical Activity Intervention on Adolescents' Mental Health: A Cluster Randomized Controlled Trial

Background: The aim of this study was to evaluate the effectiveness of a school-based multicomponent physical activity intervention on mental health of adolescents. Methods: A clustered, randomized, controlled trial was employed in 8 high schools in Dhaka, Bangladesh, which were randomly assigned to either an intervention or control group; 40 students in grades 8 and 9 from each school took part in the trial (n = 160/group). Students in the intervention schools participated in a 12-week physical activity intervention with multiple components (eg, supervised circuits, lunchtime sports, health education, infographics), while control schools received no intervention. Participants completed baseline and postintervention surveys measuring depressive symptoms (Center for Epidemiologic Studies Depression Scale) and life satisfaction (Cantril Ladder), along with other sociodemographic and behavioral characteristics. Linear mixed-effects modeling was used to evaluate the intervention effects. Results: Depressive symptoms in the intervention group decreased at postintervention, but remained stable in the control group. There was an increase in life satisfaction in the intervention group and a decrease in the control group. Multivariable modeling showed that students in the intervention group had a significantly lower level of depressive symptoms (beta = -4.60; 95% confidence interval, -5.76 to -3.46) and higher level of life satisfaction (beta = 1.43; 95% confidence interval, 0.77 to 2.10) compared with their counterparts in the control group. Sensitivity analyses supported the positive effects of the intervention. Conclusions: Our school-based, multicomponent physical activity intervention is effective in improving mental health indicators in adolescents. Future trials should be ramped up to include schools in rural and regional settings, using robust measures of mental well-being.