Minzhi Fang, Dongjin Liu
Campus fitness engagement, defined in this study as the behavioral participation of university students in physical education curricula, independent exercise, and organized sports activities within the university setting, represents a critical component of young-adult health in China. The present study examined the facilitating and barrier factors shaping campus fitness engagement among Chinese university students through a multilevel evidence synthesis framed by the Social-Ecological Model. A systematic synthesis of 43 peer-reviewed articles published between 2020 and 2025, combined with analysis of publicly available national statistical databases, was conducted to evaluate evidence at the individual, interpersonal, organizational, environmental, and policy levels. At the individual level, self-efficacy emerged as the most robust facilitator, with standardized path coefficients ranging from 0.35 to 0.46, whereas academic pressure constituted the principal barrier. At the interpersonal level, physical education teacher support operated through a chain-mediated pathway involving exercise motivation and self-efficacy, with the mediated effect accounting for 47.94% of the total effect. Organizational analysis revealed that mandatory physical education curricula exhibited a spillover effect, raising the probability of independent extracurricular exercise by 20.2%. The environmental level displayed the most pronounced facilitator-barrier asymmetry, with 14 barriers against 9 facilitators, and insufficient facility accessibility identified as the dominant structural constraint. Policy-level evidence indicated a systemic gap between policy inputs and behavioral outputs, consistent with the ranking of Chinese youth at 53rd of 57 in the 2022 global matrix assessment of physical activity. Cross-level synthesis suggested an associational pattern in which distal environmental and organizational factors are linked to proximal interpersonal and individual determinants, underscoring the limitations of single-level interventions. The findings indicate that cultivation of self-efficacy and strengthening of teacher support constitute practical short-horizon intervention priorities, whereas institutional reform and built-environment improvement represent structural priorities for systemic change. These complementary approaches provide a multilevel evidence-based foundation for targeted intervention within the Healthy China 2030 strategic framework.