Physical activity and perceived stress among secondary school students in Nantong, China: cross-sectional indirect associations through resilience and life-event impact

Physical activity is associated with better adolescent mental health, but the psychosocial processes linking activity with perceived stress remain unclear. This cross-sectional study examined indirect associations through psychological resilience and stressful life-event impact among 1,200 secondary school students in Nantong, China. Physical activity, resilience, life-event impact, and perceived stress were assessed using established self-report scales. Ordinary least-squares regression and percentile bootstrapping with 10,000 resamples were used to estimate a theory-guided serial indirect-effect model. Higher physical activity was associated with greater resilience (standardized β = 0.214, p < 0.001) and lower perceived stress (total association β = -0.124, p < 0.001). Resilience was inversely associated with life-event impact (β = -0.145, p < 0.001) and perceived stress (β = -0.143, p < 0.001), whereas life-event impact was positively associated with perceived stress (β = 0.118, p < 0.001). The resilience-only indirect association was detectable, the life-event-only pathway was not, and the small serial pathway was less robust in sensitivity analysis. Resilience was therefore the most consistent explanatory correlate. Cross-sectional self-report data preclude causal interpretation.