Buffering the effects of work stress on anxiety and depression: a moderated mediation model of physical activity enjoyment and sleep disturbance in China.

BACKGROUND: This study aimed to investigate the pathways linking work stress to anxiety and depression among a sample of full-time white-collar professionals (spanning various industries and organizational hierarchies) in China’s first-tier cities and to test the buffering role of physical activity enjoyment in this adverse process. METHODS: A cross-sectional survey was conducted with 1,546 professionals in Beijing, Shanghai, and Guangzhou. A moderated mediation model was tested using the PROCESS macro (Models 4 and 59) to examine the mediating role of sleep disturbance and the moderating role of physical activity enjoyment. RESULTS: The results indicated that work stress was significantly and positively associated with both anxiety and depression (β = 0.184, p < 0.001) and sleep disturbance (β = 0.431, p < 0.001). Sleep disturbance, in turn, was positively associated with anxiety and depression (β = 0.126, p < 0.001). Sleep disturbance partially mediated the relationship between work stress and anxiety and depression (indirect effect β = 0.071, 95% CI [0.049, 0.094]). Crucially, physical activity enjoyment significantly moderated the associations between work stress and anxiety and depression (β = -0.166, p < 0.001), between work stress and sleep disturbance (β = -0.081, p < 0.001), and between sleep disturbance and anxiety and depression (β = -0.031, p < 0.05). This moderation ultimately attenuated the strength of the overall indirect effect. CONCLUSIONS: The findings demonstrate that physical activity enjoyment is a key protective resource for mitigating the adverse mental health associations of work stress. This study extends the Effort–Reward Imbalance (ERI) and Stress-Buffering Models (SBM) and provides critical empirical evidence for workplace interventions, suggesting a strategic shift from emphasizing quantity of exercise to enhancing the quality of the exercise experience.