Abstract
BACKGROUND: While physical exercise is known to enhance college students' quality of life the underlying psychological mechanisms remain underexplored. Specifically, it is unclear how positive psychological constructs sequentially mediate this relationship. This study addresses this gap by proposing and testing a chain mediation model, investigating whether physical exercise fosters psychological flourishing, which in turn enhances optimistic intelligence, ultimately leading to improved college students' quality of life. This model provides a novel, process-oriented perspective on the benefits of physical activity. METHODS: The Physical Activity Rating Scale(PARS-3), World Health Organization Quality of Life Brief Scale (WHOQOL-BREF), Optimistic Intelligence Quotient (OQ), Flourishing Scale(FS) were used to conduct a random sampling survey among 1660 college students in China. After excluding invalid responses, 1,594 participants were included. The data were analyzed via correlation, regression, and PROCESS 3.4 bootstrapping (5,000 samples, 95% CI), controlling for sex and age. RESULTS: Physical exercise significantly predicted quality of life both directly (β = 0.051, p < .001) and indirectly through psychological flourishing (20.61% of the total effect), optimistic intelligence (25.45%), and sequential chain mediation (23.03%). The total indirect effect accounted for 69.09% of the variance explained. CONCLUSION: Physical exercise can directly promote the improvement of college students' quality of life and can also indirectly enhance it not only through the mediating effect of psychological flourishing and optimistic intelligence, but also through the chain mediating effect of the two. These results provide a theoretical reference for college students to improve their quality of life and mental health education.