Abstract
This study investigated the associations between smartphone addiction and self-esteem among undergraduate Physical Education students, focusing on the mediating roles of professional identity and meaning in life. A total of 695 undergraduate students majoring in Physical Education were recruited through a convenience sampling method from a sports university in Beijing. Participants completed the Smartphone Addiction Scale, the Professional Identity Scale for Pre-service Teachers, the Meaning in Life Questionnaire, and the Rosenberg Self-Esteem Scale. Structural equation modelling (SEM) was conducted in Mplus 8.3 to test multiple and chain mediation effects. Model fit indices indicated an acceptable fit (χ²/df = 4.43, CFI = 0.96, TLI = 0.93, RMSEA = 0.08). The results showed that smartphone addiction was significantly and negatively associated with professional identity (β = -0.42, 95% CI [-0.51, -0.32], p < 0.001) and meaning in life (β = -0.29, 95% CI [-0.38, -0.19], p < 0.001), both of which were positively associated with self-esteem (professional identity: β = 0.36, 95% CI [0.25, 0.46], p < 0.001; meaning in life: β = 0.31, 95% CI [0.21, 0.42], p < 0.001). Smartphone addiction was also directly and negatively associated with self-esteem (β = -0.27, 95% CI [-0.37, -0.18], p < 0.001). Mediation analyses further indicated that professional identity and meaning in life independently and sequentially mediated this association, forming a significant chain-mediating pathway (total indirect effect = -0.047, 95% CI [-0.071, -0.029]). The final model accounted for 38.2% of the variance in self-esteem (R² = 0.382). These findings highlight the psychological mechanisms linking smartphone addiction and self-esteem, offering evidence-based implications for interventions addressing smartphone overuse among Physical Education undergraduates.