Linking Physical Activity Motivation Regulation to Health Behavior Participation Among Korean Adults: The Mediating...

Objectives/Background: Regular physical activity is a key health behavior associated with physical and mental well-being. However, sustaining physical activity remains challenging among adults, and the psychological mechanisms that support continued engagement require further clarification. Grounded in Self-Determination Theory, this study examined the roles of autonomous motivation and controlled regulation in health behavior engagement, focusing on the mediating role of physical activity self-regulation strategies. Methods: A cross-sectional study was conducted with 468 Korean adults. Autonomous motivation and controlled regulation were assessed using the Behavioral Regulation in Exercise Questionnaire-3, and physical activity self-regulation strategies were measured using the Physical Activity Self-Regulation Scale. Health behavior engagement was assessed using a single-item measure based on the stages of change for exercise. Structural equation modeling with bootstrapping was used to examine direct and indirect relationships among the study variables. Results: Both autonomous motivation (β = 0.649, p < 0.001) and controlled regulation (β = 0.153, p < 0.001) were positively associated positive with self-regulation strategies. Self-regulation strategies were positively associated with health behavior engagement (β = 0.336, p < 0.001). Autonomous motivation showed both a significant direct effect (β = 0.131, p = 0.018) and a significant indirect effects through self-regulation strategies (bias-corrected 95% confidence interval [CI] [0.206, 0.420]) on health behavior engagement, indicating partial mediation. In contrast, controlled regulation showed no significant direct effect (β = -0.062, p = 0.144) but had a significant indirect effect through self-regulation strategies (bias-corrected 95% CI [0.043, 0.131]). Conclusions: Autonomous motivation appears to be a stronger predictor of health behavior engagement than controlled regulation, both directly and indirectly through self-regulation strategies. These findings highlight the importance of motivational quality and suggest that self-regulation strategies are a key mechanism through which motivation is translated into physical activity engagement among adults. Interventions should therefore combine autonomy-supportive approaches alongside the development of practical self-regulatory skills to promote sustained physical activity.