Effectiveness of physical activity interventions on undergraduate students' mental health: systematic review and meta-analysis.

This systematic review and meta-analysis assessed the effectiveness of physical activity interventions on undergraduate students' mental health. Seven databases were searched and a total of 59 studies were included. Studies with a comparable control group were meta-analysed, and remaining studies were narratively synthesized. The included studies scored very low GRADE and had a high risk of bias. Meta-analyses indicated physical activity interventions are effective in reducing symptoms of anxiety (n = 20, standardized mean difference (SMD) = -0.88, 95% CI [-1.23, -0.52]), depression (n = 14, SMD = -0.73, 95% CI [-1.00, -0.47]) and stress (n = 10, SMD = -0.61, 95% CI [-0.94, -0.28]); however, there was considerable heterogeneity (anxiety, I2 = 90.29%; depression I2 = 49.66%; stress I2 = 86.97%). The narrative synthesis had mixed findings. Only five studies reported being informed by a behavioural change theory and only 30 reported intervention fidelity. Our review provides evidence supporting the potential of physical activity interventions in enhancing the mental health of undergraduate students. More robust intervention design and implementation are required to better understand the effectiveness of PA interventions on mental health outcomes.