How is physical activity associated with health-related quality of life among Chinese adolescents? A serial multiple mediation model of self-control, psychological resilience, and perceived social support

Objective Although the positive association between physical activity and health-related quality of life (HRQoL) is well documented, the psychological correlates underlying this cross-sectional relationship remain incompletely understood. This study aimed to investigate whether self-control, psychological resilience, and perceived social support operate as serial statistical mediators in the association between physical activity and a study-specific HRQoL composite among Chinese adolescents. Methods A cross-sectional survey was conducted between September and November 2025 using stratified random cluster sampling across four comprehensive universities in China. A total of 3,827 Chinese adolescent students (56.5% male; mean age = 18.42 ± 0.59 years; range = 16–19 years) completed validated measures of physical activity (Physical Activity Rating Scale-3 [PARS-3]), self-control (Brief Self-Control Scale [BSCS]), psychological resilience (25-item Connor–Davidson Resilience Scale [CD-RISC-25]), perceived social support (17-item Social Support Scale for University Students [SSSUS]), and HRQoL (a study-specific composite based on 13 selected items from the World Health Organization Quality of Life-BREF [WHOQOL-BREF]). Serial mediation analysis was performed using Hayes’ PROCESS macro (Model 6) with 5,000 bias-corrected bootstrap resamples, controlling for gender, grade, and family residence. In bivariate analyses, physical activity was significantly positively associated with self-control (r = 0.129), resilience (r = 0.176), social support (r = 0.076), and HRQoL (r = 0.193; all p < 0.001). The total association between physical activity and HRQoL was significant (c = 0.152, p < 0.001), with a significant direct association remaining after including mediators (c’ = 0.067, p < 0.001). The total indirect association was 0.086 (95% CI [0.070, 0.102]), accounting for 56.3% of the total association. Six of the seven specific indirect pathways were statistically significant, with the largest effects through resilience alone (effect = 0.035, 22.8%), self-control alone (effect = 0.020, 13.2%), and the serial pathway through self-control and resilience (effect = 0.014, 9.1%). The final model explained 42.3% of the variance in HRQoL. Conclusion Among Chinese adolescents, physical activity was associated with better HRQoL both directly and through a complex pattern of indirect psychological associations. Self-control and psychological resilience emerged as the strongest statistical mediators, with perceived social support playing a smaller, more distal role. Given the cross-sectional design, these findings should be interpreted as correlational evidence consistent with theoretical mediation pathways rather than definitive causal evidence. Longitudinal and experimental studies are needed to confirm the proposed temporal sequence. These hypothesis-generating correlational findings suggest that physical activity interventions targeting HRQoL in adolescents may benefit from also fostering self-regulatory skills and psychological resilience.