The relationship between physical activity and mental health among university students: a chain mediation effect of self-efficacy and emotion regulation

Background: University students are increasingly vulnerable to mental health challenges, highlighting the need for targeted and theory-driven interventions. Physical activity has been widely recognized for its psychological benefits, yet the underlying psychological mechanisms remain insufficiently explored. Guided by the Conservation of Resources (COR) theory, this study investigates how physical activity influences mental health among university students through the chain-mediating roles of self-efficacy and emotion regulation. Methods: A cross-sectional survey was conducted among 1,395 university students in China. Validated instruments were used to assess physical activity, self-efficacy, emotion regulation, and mental health. Statistical analyses including descriptive statistics, correlation analysis, and mediation modeling were performed using SPSS 26.0 and PROCESS macro (Model 6) with 5,000 bootstrap samples. Results: The results showed significant correlations among the variables. Physical activity, as a positive resource investment behavior, significantly enhances self-efficacy and emotion regulation. These psychological resources work together to alleviate psychological distress. Chain mediation analysis indicated that self-efficacy and emotion regulation play a chain mediating role in the relationship between physical activity and mental health. Conclusion: This study advances our understanding of the psychological pathways linking physical activity to mental health by revealing a dual-step mediation mechanism. The findings highlight the importance of enhancing self-efficacy and emotional regulation in university-based mental health interventions. Integrating physical activity with psychological skill-building may offer an effective approach to promoting mental well-being in higher education settings.