The Impact of Exercise Commitment on Flourishing via Psychological Capital (PsyCap): A Second-Order PLS-SEM Approach

Objectives: For the younger generation (i.e., Millennials and Generation Z), running is not only about physical health, but also about building psychological resources and multidimensional well-being, reflecting their unique culture and lifestyle. This study aims to investigate the structural relationships among exercise commitment, psychological capital (PsyCap), and flourishing in younger adults in South Korea by integrating Social Cognitive Theory (SCT) and Broaden-and-Build Theory (BBT) using a second-order partial least squares structural equation modeling (PLS-SEM). Methods: A total of 166 participants were recruited through convenience sampling via online survey. They were young South Korean adults (born 1983–2005) who run at least once a week and were recruited through two universities and running communities. The survey included validated scales measuring exercise commitment (cognitive and behavioral), PsyCap (hope, efficacy, resilience, and optimism), and flourishing (emotional, psychological, and social well-being). Data were analyzed using PLS-SEM with 5000 bootstrap resamples in SmartPLS 4.1.1.2. Subsequently, measurement and structural models were assessed through confirmatory composite analysis (CCA), and common method variance (CMV) was checked using Harman’s single-factor test. Results: Exercise commitment significantly predicted PsyCap (β = 0.171, p < 0.05) and PsyCap significantly predicted flourishing (β = 0.444, p < 0.001). Mediation analysis confirmed that PsyCap fully mediated the relationship between exercise commitment and flourishing (β = 0.071, p < 0.05). Although the indirect effect may appear numerically small, it translated to a 7.1% increase in flourishing scores—a practically meaningful effect in social science contexts where even modest changes yield real-world impact. The findings empirically support the integration of two frameworks, highlighting both motivational (SCT) and affective (BBT) pathways through which exercise fosters multidimensional well-being. Conclusions: Theoretically, this study advances understanding of how cognitive and behavioral commitment contribute to the development of psychological resources that collectively drive flourishing. Practically, the results suggest that running programs targeting younger adults should focus on fostering PsyCap—via goal setting, social support, and digital engagement—to maximize well-being outcomes. Moreover, the findings have the potential to inform mental health promotion strategies beyond the Korean context. This study has several limitations, including a skewed sample resulting from convenience sampling, the lack of comparative analysis across different age cohorts, and the use of second-order constructs that may obscure dimension-specific effects. Future research should address these limitations by employing stratified sampling, adopting comparative study designs, and conducting model comparisons between first- and second-order constructs to elucidate both overarching and dimension-specific pathways.