Abstract
OBJECTIVE: This study aimed to examine the association between physical activity and mental health among Chinese university students and to test a serial mediation model in which sports lifestyle and phubbing act as sequential mediators. METHODS: A cross-sectional survey was conducted among 3,009 university students from Linyi University in Shandong Province, China. Physical activity was assessed using the International Physical Activity Questionnaire-Short Form (IPAQ-SF). Sports lifestyle was measured with the Sports Lifestyle Form(SLF), phubbing with the General Scale of Phubbing (GSP), and mental health with the Depression, Anxiety, and Stress Scale-21 (DASS-21), with higher scores indicating poorer mental health. Pearson correlation analyses were conducted, followed by a regression-based serial mediation analysis using PROCESS Model 6 with 5,000 bootstrap samples, controlling for age and gender. RESULTS: Physical activity was significantly associated with mental health (total effect: β=-0.123, p < 0.001). Sports lifestyle significantly mediated this association (indirect effect: β=-0.014, 95%CI [- 0.022,-0.006]), accounting for 11.12% of the total effect. Phubbing also served as a significant mediator (indirect effect: β=-0.041, 95%CI [- 0.062,-0.021]), accounting for 33.52% of the total effect. In addition, a significant serial mediation pathway was observed through sports lifestyle and phubbing (physical activity→sports lifestyle→phubbing→mental health; indirect effect:β=-0.014, 95%CI [- 0.020,-0.009]), accounting for 11.53% of the total effect. The total indirect effect accounted for 56.07% of the overall association, while the direct effect of physical activity on mental health remained significant (β=-0.054, p < 0.001), indicating partial mediation. CONCLUSION: The association between physical activity and mental health among university students is explained through both direct effects and multiple indirect behavioral pathways. Sports lifestyle and phubbing independently and sequentially mediate this relationship, highlighting the importance of promoting sports lifestyle and reducing phubbing to enhance mental health outcomes.