AUTHOR=Ge Sha , Zhao Yifan , Song Haoze , Guo Xuepeng , Song Chao TITLE=A multilevel impact study of Chinese adolescents’ sports participation based on ecological models of health behavior: a structural equation model analysis JOURNAL=Frontiers in Psychology VOLUME=Volume 16 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2025.1593491 DOI=10.3389/fpsyg.2025.1593491 ISSN=1664-1078 ABSTRACT=Despite the growing awareness of the health benefits of physical activity participation among adolescents, physical inactivity remains a pressing concern for many adolescents around the globe. Using Ecological models of health behavior as a guide, this study investigated the combined effects of environmental, organizational, interpersonal, and individual factors on Chinese junior high school students’ sport participation. A four-level structural equation model (SEM) integrating environmental, organizational, interpersonal, and individual factors was developed for 780 students (51.79% boys, 48.21% girls) from nine middle schools in Heping District of Tianjin. The model showed acceptable fit (CMIN/DF = 2.601, GFI = 0.949, CFI = 0.971, TLI = 0.965, RMSEA = 0.045), and correlation analyzes indicated that sport participation was moderately positively correlated with personal, interpersonal, organizational, and environmental factors (r = 0.476–0.531, p < 0.01). Structural equation modeling further confirmed that Environmental Factors (Env.F), Organizational Factors (Org.F), Interpersonal Factors (Int.F) and Individual Factors (Ind.F) had significant direct and indirect effects on sport participation (SP). Multiple and interlocking mediation paths emerged, indicating partial mediation between the four levels. “Int.F → Ind.F → SP” showed a strong indirect effect (β = 0.124, 95% CI [0.043, 0.221]), emphasizing the critical role of interpersonal support and personal confidence in shaping youth sport participation. Further, the most extensive chain, “Env.F → Org.F → Int.F → Ind.F → SP,” also emerged as a valid path, with an indirect effect of β = 0.027 (95% CI [0.010, 0.052]). The results suggest the need for a multilevel intervention that coordinates environmental and organizational resources, strengthens family and peer support, and fosters individual self-efficacy to ultimately promote sustained youth participation in sports.