Abstract
BACKGROUND: Socioeconomic status (SES) has been associated with various health outcomes, yet its relationship with physical activity remains inconclusive. AIMS: Grounded in self-identity theory, this research aimed to examine the effects of both subjective and objective SES on physical activity, and tested whether exercise identity mediates these effects and whether gender moderates them. METHOD: This research recruited 339 participants who completed a three-wave survey at two-week intervals. Objective SES was assessed using annual household income; subjective SES was measured with the MacArthur Scale of Subjective Social Status; exercise identity was assessed using the Exercise Identity Scale; and physical activity was measured via a single item assessing activity frequency. Preliminary analyses were conducted using SPSS 26.0, and time-lagged moderated mediation analyses were conducted using Mplus 8.0. RESULTS: Subjective SES was positively associated with physical activity (β = 0.10, p = 0.049), whereas objective SES showed no direct association (β = 0.01, p = 0.877). Exercise identity significantly mediated the associations of both objective SES (Effect = 0.01, 95% CI [0.002, 0.027]) and subjective SES (Effect = 0.02, 95% CI [0.004, 0.034]) with physical activity. Interestingly, gender moderated the mediated pathway for objective SES (β = 0.14, p = 0.008, 95% CI [0.031, 0.242]). Specifically, the mediation effect via exercise identity was significant for men (β = 0.10, p = 0.003, 95% CI [0.041, 0.172]) but not for women (β = -0.02, p = 0.611, 95% CI [- 0.080, 0.052]). LIMITATIONS: This research relied on self-reported measures and the convenience sample of college students from mainland China, which may introduce bias and constrain the generalizability of the findings. CONCLUSION: Objective and subjective SES differentially affect exercise identity and physical activity. Moreover, gendered expectations appear to modify the pathway from objective SES to physical activity via exercise identity, suggesting that interventions to promote exercise might benefit from consideration of both socioeconomic and identity-related factors.