Abstract
BACKGROUND: With the accelerating global trend of population aging, health problems among older adults have become a major public health challenge. Drawing on the theory of health empowerment, this study aimed to examine how physical exercise influences physical functioning in older adults through the chained mediating effects of social participation and depression, thereby clarifying its underlying mechanisms. METHODS: Data were obtained from the 2018 wave of the China Health and Retirement Longitudinal Study (CHARLS), including 3,527 individuals aged 60 years and above. Regression analyses were conducted using SPSS 29.0, and mediation effects were tested with the SPSS PROCESS macro (Model 6). Structural equation modeling with AMOS 28.0 was applied to evaluate the model fit and confirm the robustness of the mediation effects. RESULTS: Statistical analyses indicated that physical exercise was significantly associated with improved physical functioning among older adults (total effect β = −0.784, p < 0.01). The direct effect was β = −0.449 (57.27%), and the indirect effect was β = −0.335 (42.73%). Mediation tests showed that physical exercise indirectly improved physical functioning by enhancing social participation (β = −0.079, 10.08%) and by reducing depressive symptoms (β = −0.214, 27.30%). In addition, social participation exerted a chain-mediating effect via reductions in depressive symptoms (β = −0.042, 5.36%). The mediation model demonstrated good fit (χ²/df = 2.35, RMSEA = 0.072, IFI/TLI/CFI > 0.90), indicating satisfactory generalizability and predictive validity. CONCLUSION: Participation in physical exercise is statistically significantly associated with better physical functioning among older adults. The underlying mechanisms may involve multiple pathways. (1) a direct pathway related to improvements in physiological functions; (2) an indirect pathway through increased social participation and alleviated depressive symptoms, whereby greater social interaction and reduced negative affect indirectly promote physical functioning; (3) a potential chain-mediated pathway of “exercise participation → expanded social networks → improved mental health → optimized physical functioning.” It should be noted, however, that a cross-sectional design cannot establish causality; longitudinal or experimental studies are recommended to verify the directionality of these pathways.