The mechanism of mandatory exercise check-in on college students’ intention to use fitness apps: a complete mediation model

Based on the Theory of Planned Behavior (TPB), this study investigates the underlying motivational mechanism linking subjective norms (SN) to the behavioral intention (BI) to use fitness applications among college students. A questionnaire survey was conducted on 387 university students in Shanghai to construct a sequential mediation model. The results reveal that while SN has a significant total effect on app usage intention, its direct effect is statistically insignificant. Crucially, the analysis confirms that the relationship between SN and BI is entirely driven by a complete serial mediation involving Self-determined Motivation (SDM) and Exercise Volume (EV). This mechanism reveals that external norms influence intention predominantly through the process of internalization mediated by SDM. The findings emphasize that the long-term efficacy of mandatory policies hinges on fostering intrinsic motivation. Therefore, higher education sports policies should shift from a purely task-driven framework to a motivation-driven approach to effectively enhance exercise quality and cultivate students’ autonomous and persistent exercise habits.