Abstract / Summary
BackgroundSchool-based physical activity (PA) interventions are a population-level strategy for improving children’s health, yet evidence on their combined effects on physical fitness and psychosocial adaptation remains fragmented. This systematic review and meta-analysis synthesized evidence from controlled intervention trials (randomized and non-randomized) examining school-based PA interventions on physical fitness (cardiorespiratory fitness, muscular fitness, body composition) and psychosocial adaptation (self-esteem, psychological well-being, social functioning) in children aged 6–12 years.MethodsFollowing PRISMA 2020 guidelines, we searched PubMed, Web of Science, Embase, SPORTDiscus, Cochrane Library, and PsycINFO from inception to 15 January 2026. Randomized controlled trials (RCTs) and non-randomized controlled trials with a minimum 8-week school-based PA intervention and at least one physical fitness or psychosocial outcome were eligible. Random-effects meta-analyses were performed using Hedges’ g. Heterogeneity was assessed with I2 and Cochran’s Q. Risk of bias was evaluated using the Cochrane Risk of Bias 2 tool for RCTs and ROBINS-I for non-randomized trials.ResultsForty studies (39 randomized, 1 non-randomized) involving 21,793 participants met inclusion criteria. School-based PA interventions were associated with significant improvements in cardiorespiratory fitness (g = 0.36, 95% CI [0.25, 0.46], p < 0.001, I2 = 98%) and muscular fitness (g = 0.24, 95% CI [0.17, 0.31], p < 0.001, I2 = 93%); the small reduction in body mass index did not reach statistical significance (g = −0.11, 95% CI [−0.27, 0.04], p = 0.154, I2 = 98%). For psychosocial outcomes, significant small effects were found for self-esteem (g = 0.18, 95% CI [0.10, 0.27], p < 0.001), psychological well-being (g = 0.15, 95% CI [0.09, 0.21], p < 0.001), and social functioning (g = 0.21, 95% CI [0.04, 0.38], p = 0.018). Exploratory subgroup analyses suggested that larger effects were associated with multicomponent interventions, durations of ≥24 weeks, and ≥3 sessions per week.ConclusionSchool-based PA interventions were associated with small-to-moderate improvements in physical fitness and small improvements in psychosocial adaptation in children. The findings support integrating comprehensive PA programs into school curricula. However, the small effect sizes for psychosocial outcomes and substantial heterogeneity underscore the need for rigorous studies with standardized measurement protocols.