Physical activity and psychological distress among older adults in China: a three-wave random-intercept cross-lagged study

Background Physical activity and psychological distress are relevant to aging well, but their prospective relationship within an individual remains uncertain. We examined this relationship, together with time patterns and gender differences, among older adults recruited at senior education institutions in China. Methods Participants were surveyed in March, July, and December 2025. We measured physical activity with the PARS-3 and psychological distress with the raw DASS-21 total. A random-intercept cross-lagged panel model separated stable between-person differences from within-person deviations and adjusted for available demographic covariates. All 1,392 baseline participants were included using robust maximum likelihood with full information maximum likelihood. Secondary mixed repeated-measures ANOVAs examined time, gender, and their interaction in 1,137 three-wave completers. Results Higher-than-usual activity was associated with lower subsequent distress at both intervals ( β = −0.099 and −0.127; p = 0.018 and 0.003). The reverse estimate was negative with a confidence interval including zero at the first interval ( β = −0.062, p = 0.143) and positive at the second ( β = 0.086, p = 0.024). Women reported higher distress (partial η 2 = 0.0113); the gender difference in activity was very small (partial η 2 = 0.0034). The distress time effect was small (partial η 2 = 0.0033), and no activity time effect or time-by-gender interactions were detected. Conclusion Activity above an individual’s usual level preceded lower distress at both intervals, with modest associations and no consistent negative reverse pattern. Women’s higher observed distress and the small mean changes complement this account of activity and emotional health among older learners.