An investigation of the relationship between grit, physical activity, and self-efficacy: a variable-centered and person-centered approach.

Background: Grit, defined as perseverance and passion for long-term goals, is a vital psychological trait that contributes to academic success and overall wellbeing. At the same time, regular PA supports physical and mental health, yet its engagement often declines among university students. Although grit has been linked to health-promoting behaviors, the mechanisms underlying this association remain unclear. This study investigated the mediating role of self-efficacy from a variable-centered perspective and identified student profiles based on grit and self-efficacy through a person-centered approach. Methods: A cross-sectional survey of 3,752 Chinese university students was conducted. Structural equation modeling tested the mediating role of self-efficacy in the grit-PA relationship. Latent Profile Analysis identified subgroups with distinct combinations of grit and self-efficacy, with PA levels compared across profiles. Results: The variable-centered analysis revealed that grit was positively associated with PA (β = 0.370, p < 0.001), with self-efficacy serving as a significant partial mediator, accounting for 21% of the total effect (indirect effect = 0.077, 95% CI [0.058, 0.097]). The person-centered analysis identified three distinct profiles: "Limited Self-Regulation" (16.12%), "Moderate Self-Regulation" (55.84%), and "Strong Self-Regulation" (28.04%). Students in the Strong Self-Regulation profile demonstrated significantly higher PA engagement (M = 49.03) compared to those in the Moderate (M = 31.56) and Limited (M = 17.84) profiles (F = 225.11, p < 0.001, η2 = 0.107). Conclusion: Self-efficacy is consistent with a mediating role linking grit to PA among university students. The identification of three distinct profiles reveals meaningful heterogeneity in motivational configurations. Students with high grit and self-efficacy demonstrate optimal PA engagement, while those low in both represent a vulnerable subgroup requiring targeted intervention. Integrating variable- and person-centered approaches provides a comprehensive understanding of motivational processes underlying active lifestyles in higher education, emphasizing the need for tailored, profile-specific interventions.