Classroom-based physical activity and sedentary behavior interventions in adolescents: a systematic review and meta-analysis

Background: It is reported that 81% of adolescents are insufficiently active. Schools play a pivotal role in promoting physical activity (PA) and reducing sedentary behavior (SB). The aim of this systematic review and meta-analysis was to evaluate classroom-based PA and SB interventions in adolescents. Methods: A search strategy was developed using the PICOS framework. Articles were screened using strict inclusion criteria. Study quality was assessed using the Effective Public Health Practice Project quality assessment tool ( http://www.ephpp.ca/tools.html ). Outcome data for preintervention and postintervention were extracted, and effect sizes were calculated using Cohen’s d. Results: The strategy yielded 7574 potentially relevant articles. Nine studies were included for review. Study quality was rated as strong for 1 study, moderate for 5 studies, and weak for 3 studies. Five studies were included for meta-analyses, which suggested that the classroom-based interventions had a nonsignificant effect on PA (P=.55, d=0.05) and a small, nonsignificant effect on SB ( P=.16, d=−0.11). Conclusion: Only 9 relevant studies were found, and the effectiveness of the classroom-based PA and SB interventions varied. Based on limited empirical studies, there is not enough evidence to determine the most effective classroom-based methodology to increase PA and SB.