Aerobic exercise for depression symptoms in adolescents: a systematic review and dose-response meta-analysis

Adolescent depression has become a significant global public health issue. Several meta-analyses have highlighted the potential of aerobic exercise in improving depression symptoms. However, the dose-response effect of aerobic exercise on depression symptoms in adolescents remains unclear. The present study aims to systematically assess the effects of aerobic exercise on adolescent depression symptoms through a Bayesian dose-response meta-analysis, while also delineating the dose-response curve to provide quantitative evidence for the formulation of clinical exercise prescriptions. A systematic search of the literature was conducted in PubMed, Embase, Scopus, Web of Science, and EBSCO from database inception to August 2025. Inclusion criteria were strictly defined to include randomized controlled trials (RCTs) that investigated aerobic exercise interventions targeting depression symptoms in adolescents aged 12–19 years. Two independent researchers assessed the methodological quality of the included studies using the Cochrane Risk of Bias Tool 2.0. Data synthesis was performed using a Bayesian random-effects model to explore the nonlinear relationship between the aerobic exercise dose (quantified in MET-min/week) and improvement in depression symptoms. A total of 12 studies involving 723 participants were included. The Bayesian meta-analysis revealed that aerobic exercise intervention significantly improved depression symptoms in adolescents compared to control groups, demonstrating a small effect size (Hedges’ g = -0.28, 95% credible interval (CrI): -0.43 to -0.13). The dose-response analysis revealed a significant nonlinear relationship between aerobic exercise dose and effects. As the exercise dose increased, the effect initially intensified, peaking at approximately 740 METs-min/week (Hedges’ g = -0.44, 95% CrI: -0.27 to -0.73) based on exiting evidence, after which further increases in dose were associated with a diminishing effect on symptom improvement. The evidence from this study suggests that aerobic exercise intervention has significant benefits in improving depression symptoms in adolescents, supporting aerobic exercise as an effective intervention for adolescent depression. The study also identifies the dose of 740 METs-min/week for alleviating adolescent depression symptoms. It is crucial to emphasize that this is a point estimate derived from the available data, and its precision is reflected in the associated credible intervals. These findings have important implications for improving depression symptoms and enhancing the quality of life in adolescents.