Physical activity and risk of depression in adolescents: A systematic review and meta-analysis of prospective observational studies

Background: While the benefits of physical activity (PA) on depression in adults have been well-established, its impact on depression in adolescents remains understudied. This study aimed to examine the relationship between PA and depression in adolescents, aggregating published prospective observational studies. Methods: We searched MEDLINE, Embase, Cochrane, and PsycINFO, for prospective observational studies that examined the relationship between PA and depression in adolescents from the inception of these databases to November 17, 2022, without any language restrictions. Two independent reviewers performed data extraction and assessed the risk of bias. We utilized a random-effects model to calculate the pooled odds ratios (ORs) and 95 % confidence intervals (95%CIs). Subgroup analyses were conducted to explore potential sources of heterogeneity. Results: This study included 11 original articles, involving 59,786 adolescents (46.4 % male). Primary analysis revealed that adolescents who engaged in higher levels of PA showed a 3 % significantly decreased risk of developing depression compared to those with lower levels (OR = 0.97, 95%CI = 0.94-0.99, P = 0.01; I-2 = 41.7 %). Sensitivity analyses confirmed the robustness of these findings. Subgroup analyses demonstrated heterogeneity to be primarily attributed to data source, geographic region, and follow-up period (P-interaction < 0.01, 0.01 and 0.01, respectively), while no significant sex-specific association was found (P-interaction = 0.30). Conclusions: Our systematic review and meta-analysis of prospective observational studies indicates that higher levels of PA are associated with a reduced risk of depression in adolescents. This highlights the need for policies to promote increased PA levels among adolescents for the prevention of depression.