Autonomous Motivation Moderates the Relationship Between Fitness Application Usage and Exercise Behavior Through Flow Experience: A Cross-Sectional Study Among Chinese University Students

Background: While mobile fitness applications have proliferated globally, their effectiveness in promoting physical activity among university students remains inconsistent, with high attrition rates reported. Understanding the psychological mechanisms underlying application usage and exercise behavior is crucial for optimizing digital health interventions. This study examined a moderated mediation model investigating how autonomous motivation regulates the relationship between fitness application usage and exercise behavior through flow experience among Chinese university students.Methods: A cross-sectional survey was conducted with 350 university students (56.0% male, mean age 20.4 years) actively using fitness mobile applications in China. Participants completed validated questionnaires measuring fitness application usage, flow experience, autonomous motivation, and physical activity levels (assessed via International Physical Activity Questionnaire). Data were analyzed using hierarchical regression analysis and bootstrapping procedures with 5,000 resamples to test the moderated mediation model.Results: The moderated mediation model demonstrated excellent fit, explaining 74.3% of variance in flow experience and 46.9% in exercise behavior. Autonomous motivation significantly moderated the relationship between application usage and flow experience (β = 0.423, p