A cross-level study on the impact of teacher experience, positive teacher-student relationships and exercise self-efficacy on physical activity among students within a multi-level framework

Physical inactivity among college students remains a global public health challenge, yet limited studies have explored multilevel mechanisms integrating teacher- and student-level factors. This study investigates how teacher experience (TE), positive teacher-student relationships (PTSR), and exercise self-efficacy (ESF) jointly influence college students’ physical activity (PA), with a focus on cross-level interactions and mediating pathways. A cross-sectional design included 592 student-teacher dyads from 40 universities in Beijing. PA was objectively measured using ActiGraph GT3X accelerometers. PTSR and ESF were assessed via validated questionnaires (Cronbach’s α = 0.709–0.813). Hierarchical linear modeling (HLM) tested direct, mediating, and moderating effects. Results: TE (γ01 = 0.028, SE = 0.010, p = 0.008), PTSR (t = 5.353, 95% CI [0.122, 0.264], p < 0.001), and ESF (t = 9.131, 95% CI [0.414, 0.641], p < 0.001) directly predicted higher PA. ESF mediated 34.3% of the PTSR-PA relationship (indirect effect = 0.101, Sobel Z = 5.931, p < 0.01). Paradoxically, TE negatively moderated the ESF-PA link (γ21 = −0.025, p = 0.045), suggesting experienced teachers may unintentionally weaken efficacy-driven participation. No cross-level effect was found for TE on PTSR (γ01 = 0.011, p = 0.215). Conclusion: This study pioneers a multilevel PA framework, revealing ESF’s critical mediating role and TE’s counterintuitive moderation. Findings urge pedagogical reforms prioritising adaptive teaching over experience accumulation and institutional policies fostering teacher-student rapport. Regional sampling and cross-sectional data limit generalizability; future work should adopt longitudinal designs across diverse contexts.