Children's physical activity and depression: A meta-analysis

Abstract

CONTEXT: Research regarding the protective effects of early physical activity on depression has yielded conflicting results. OBJECTIVE: Our objective was to synthesize observational studies examining the association of physical activity in childhood and adolescence with depression. DATA SOURCES: Studies (from 2005 to 2015) were identified by using a comprehensive search strategy. STUDY SELECTION: The included studies measured physical activity in childhood or adolescence and examined its association with depression. DATA EXTRACTION: Data were extracted by 2 independent coders. Estimates were examined by using random-effects meta-analysis. RESULTS: Fifty independent samples (89 894 participants) were included, and the mean effect size was significant (r=-0.14; 95% confidence interval [CI]=-0.19 to-0.10). Moderator analyses revealed stronger effect sizes in studies with cross-sectional versus longitudinal designs (k=36, r=-0.17; 95% CI=-0.23 to-0.10 vs k=14, r=-0.07; 95% CI=-0.10 to-0.04); using depression self-report versus interview (k=46, r=-0.15; 95% CI=-0.20 to-0.10 vs k=4, r=-0.05; 95% CI=-0.09 to-0.01); using validated versus nonvalidated physical activity measures (k=29, r=-0.18; 95% CI=-0.26 to-0.09 vs k=21, r=-0.08; 95% CI=-0.11 to-0.05); and using measures of frequency and intensity of physical activity versus intensity alone (k=27, r=-0.17; 95% CI=-0.25 to-0.09 vs k=7, r=-0.05; 95% CI=-0.09 to-0.01). LIMITATIONS: Limitations included a lack of standardized measures of physical activity; use of self-report of depression in majority of studies; and a small number of longitudinal studies. CONCLUSIONS: Physical activity is associated with decreased concurrent depressive symptoms; the association with future depressive symptoms is weak.