Consistent physical activity is vital for optimal physical and mental health. Numerous studies demonstrate its positive influence on psychological resilience, mental well-being, and health-related behaviors. The COVID-19 pandemic underscored the importance of psychological support in overcoming barriers to physical activity and highlighted exercise's positive impact on mental health. Existing research shows a strong correlation between regular physical activity and improved mental well-being, encompassing enhanced subjective well-being, stress reduction, and cognitive enhancement. While the benefits of physical activity are established, research investigating these relationships while considering quality of life as a moderating factor is limited. This study aims to address this gap by examining the influence of physical activity on health behavior, mental health, and psychological resilience, considering the moderating role of quality of life. The study also acknowledges the importance of factors like aging, home-based exercise, and the varied impacts of physical activity across different age groups and communities.

The literature extensively supports the positive effects of physical activity on mental and physical well-being. Studies show negative correlations between diabetes prevalence and higher physical activity levels, even after accounting for air pollution. Regular physical activity is crucial for preventing and managing chronic diseases and improving mental health. Moreover, physical activity is linked to increased psychological resilience, particularly in older adults. Aerobic and strength training improve mental health and brain function. However, the literature lacks comprehensive studies exploring the interplay between physical activity, health behavior, mental health, psychological resilience, and the moderating role of quality of life. This study bridges this gap.

A cross-sectional online survey was conducted in China from April 15, 2023, to October 15, 2023, collecting data from over 1,000 participants. After data cleaning, 743 responses were analyzed. Participants were over 21 and actively engaged in physical activity for health improvement. The survey included measures for physical activity (five-point Likert scale assessing frequency of various activity types), health behavior (five-point Likert scale assessing agreement with healthy practices), quality of life (five-point Likert scale assessing different aspects of well-being), mental health (five-point Likert scale measuring frequency of positive feelings), and psychological resilience (five-point Likert scale assessing agreement with resilience statements). Data were analyzed using SPSS-25 for descriptive statistics and SmartPLS 4.0 for structural equation modeling (SEM). Two SEM models were developed: Model 1 (direct effects) and Model 2 (direct and moderating effects of QoL). Measurement reliability and validity were assessed using composite reliability, average variance extracted (AVE), Cronbach's alpha, Fornell-Larcker criterion, and Heterotrait-Monotrait ratio of correlations (HTMT). Model fit was evaluated using SRMR, d_ULS, d_G, Chi-square, and NFI. Hypotheses were tested using path coefficients (β), standard deviations, p-values, and t-values.

SEM analysis of Model 1 (direct effects) showed significant positive relationships between PA and HeB (β = 0.660, p < 0.000), PA and MeH (β = 0.554, p < 0.000), PA and PsR (β = 0.196, p < 0.000), HeB and MeH (β = 0.539, p < 0.000), HeB and PsR (β = 0.476, p < 0.000), and MeH and PsR (β = 0.164, p < 0.000). Model 2, which incorporated QoL as a moderator, revealed that QoL significantly moderated four out of six relationships: PA→HeB (β = 0.062, p < 0.05), HeB→PsR (β = 0.084, p < 0.05), MeH→PsR (β = -0.116, p < 0.05), and PA→PsR (β = -0.087, p < 0.05). The moderating effects of QoL on PA→MeH and HeB→MeH were not significant. The findings suggest that while PA consistently had positive direct effects on HeB, MeH, and PsR, the strength of these relationships varied depending on an individual's QoL.

The findings strongly support the positive impact of regular physical activity on health behavior, mental health, and psychological resilience. The significant moderating role of quality of life highlights the importance of a holistic approach to health promotion. Interventions should not only focus on increasing physical activity but also on improving overall quality of life to maximize the benefits of exercise. This nuanced understanding aligns with previous research highlighting the interconnectedness of physical and mental well-being. The results suggest that improving quality of life may amplify the positive impacts of physical activity on various aspects of health and well-being.

This study demonstrates the significant positive impact of physical activity on health behavior, mental health, and psychological resilience, with quality of life playing a crucial moderating role. Consistent engagement in physical activity is vital for holistic health. Future research should explore longitudinal relationships and examine the impact of diverse factors on these associations, especially within different demographic groups. Further research may also consider the types of physical activity performed and the intensity of the exercise.

The cross-sectional design limits the ability to establish causality. Convenience sampling may limit the generalizability of the findings to other populations. The focus on participants actively engaging in physical activity for health reasons may limit the applicability of findings to individuals with different motivations. Further research is needed to explore other potentially influential factors.