The effects of physical activity on adolescent psychological sub-health: chain-mediated effects of self-control and mobile phone addiction | BMC Psychology

The objective of this study was to illuminate the mechanisms by which physical activity influences adolescent PSH, employing a chain mediation model that includes physical activity, SC, and MPA. Results reveal that physical activity exerts a significant effect on PSH through SC, MPA, and their sequential mediation. This study enriches the theoretical discourse on how physical activity impacts adolescent mental health and offers empirical evidence supporting the development of comprehensive strategies to mitigate adolescent mental health issues.

The relationship between PA and adolescent PSH

The research demonstrated a robust negative link between physical activity and PSH, affirming physical activity as a negative predictor of adolescent PSH and supporting Hypothesis 1. Existing literature corroborates that physical activity not only boosts adolescent physical health but is also crucial in enhancing psychological health [7]. Regular physical activity has been found to enhance social adaptability [35], foster positive interpersonal relationships [36], and stimulate creativity and innovation [37]. These benefits can be attributed to PA’s ability to regulate neurotrophic factors and glucocorticoid hormones, stimulate hippocampal neurons in the central nervous system, and effectively alleviate psychological symptoms such as anxiety and depression in adolescents [38]. Furthermore, engaging in appropriate PA stimulates the pituitary gland to release endorphins, inducing a sense of euphoria that helps reduce negative emotions, thus improving PSH [39]. PA also enhances the metabolism of nervous system components, improving overall nervous system regulation and mental health [40]. Moreover, by adjusting exercise frequency, duration, and intensity, adolescents can manage stress and relieve tension, further promoting mental well-being [5]. Consequently, adolescents who are actively involved in physical activity experience lower rates of PSH, highlighting the critical role that PA plays in improving adolescent mental health.

The mediating role of SC between physical activity and adolescent PSH

The study also established that physical activity positively influences adolescent PSH through the mediating role of SC. It was observed that physical activity significantly fosters SC, which in turn correlates with reduced PSH in adolescents. These findings uphold Hypothesis 2, suggesting that SC partially mediates the effect of physical activity on adolescent PSH. According to the SC strength model, SC, similar to physical muscles, may deplete psychological energy but can be replenished and strengthened through regular physical activity [41]. This provides a theoretical basis for the link between PA and enhanced SC. Further empirical support is found in studies showing that physical activity positively influences SC levels in adolescents [11], consistent with the results of this investigation. Adolescents exhibiting high SC are more adept at managing undesirable behaviors and enhancing their psychological health, thus fostering better social relationships and adaptability [42]. Such individuals typically exhibit better psychological adjustment, stronger relationships, and higher life satisfaction. They are also better at managing their daily routines, adapting to environmental demands more quickly, and performing better academically or professionally, all of which contribute to fewer PSH issues. Moreover, adolescent mental health issues may relate to functional impairments in the prefrontal cortex, which plays a pivotal role in executive functions and impulse control, highlighting the critical nature of SC in adolescent mental health. Therefore, regular physical activity bolsters SC, which in turn ameliorates PSH.

The mediating role of MPA between PA and adolescent PSH

This study also uncovered that physical activity impacts adolescent PSH through the intermediary role of MPA. It was observed that physical activity significantly decreases MPA, which is directly correlated with increased PSH issues among adolescents. These results substantiate Hypothesis 3, affirming that MPA serves as a partial mediator in the linkage between physical activity and adolescent PSH. Existing literature corroborates the notion that physical activity mitigates MPA in this demographic [43]. Exercise enhances the structure and function of specific brain regions, regulates dopamine and its receptors, and helps correct MP-related addictive behaviors in adolescents [44]. During physical activity, the excitation centers in the cerebral cortex shift to more excitably active regions, allowing overstimulated neurons to rest, which helps redirect attention from MPs and alleviates addiction to them [45]. Furthermore, PA strengthens willpower, and adolescents with greater willpower are more likely to engage in positive behaviors to solve problems, thereby reducing their dependence on MPs. Exercise also fulfills certain psychological needs, thereby reducing adolescents’ desire to use MPs, which, in turn, alleviates MPA. Studies from Malaysia, China, Iran, Saudi Arabia, and Brazil have indicated that excessive MP use can negatively impact both physical and mental health in adolescents, contributing to symptoms such as headaches, insomnia, irritability, and poor concentration, as well as increasing the risk of anxiety and depression [18]. MPA not only fosters a fear of missing out on information but also reduces face-to-face communication, leading to social anxiety. While smartphones have revolutionized communication, learning, and entertainment for adolescents, they have also heightened compulsive use and dependency, exacerbating PSH. The results of this study suggest that PA effectively mitigates MPA, thereby contributing to a reduction in PSH issues among adolescents.

Chain mediation of SC and MPA between physical activity and adolescent PSH

Additionally, the study highlights that physical activity affects adolescent PSH via a chain mediation model that includes both SC and MPA. More specifically, an increase in physical activity enhances SC, which subsequently curtails symptoms of MPA, thereby promoting better PSH. These outcomes lend support to Hypothesis 4, proposing that the interaction between SC and MPA mediates the effect of physical activity on adolescent PSH. Previous studies align with this finding, indicating that adolescents with diminished SC are more prone to elevated MPA [46]. Lower SC undermines an adolescent’s capacity to curb impulses, resist habitual actions, and favor long-term objectives over instant rewards, complicating their ability to withstand MP allure. This typically leads to inadequate planning, reduced response inhibition, and experiences of ennui or distress when disconnected from MPs. Such reliance on mobile devices offers immediate gratification, while disengagement from these devices can precipitate a sensation of joylessness, thus perpetuating addictive behaviors. These insights are consistent with Brand et al.‘s I-PACE model, which posits that deficits in managing executive and inhibitory functions diminish the motivation required for effective self-regulation, thereby facilitating addictive behaviors [47]. During physical activity, adolescents expend energy, and when they are able to better manage their exercise routines, their SC improves. Successfully completing these activities also satisfies basic psychological needs, which in turn reduces MPA behaviors [35], leading to a decrease in PSH symptoms. The chain mediation model in this study offers valuable insights into the mechanisms through which PA influences adolescent PSH, expanding intervention strategies for adolescent mental health and providing both theoretical and practical recommendations for using physical activity to enhance adolescent well-being.

Limitations

This study has certain limitations. First of all, the PSH of adolescents may change over time. However, since only one questionnaire survey was conducted, it cannot capture the changes in PSH over time, and further longitudinal studies should be conducted. Secondly, in this study, we only assessed the impact of the SCS and MPA on the variables of interest. Future research could consider including other factors, such as mental resilience, social anxiety, fear of missing out, and peer relationships. Thirdly, the study only examined the effects of PA on the overall status of PSH, and the effects of PA on more refined dimensions of PSH, such as emotional subhealth, behavioural subhealth, and social adjustment subhealth, can be further explored in the future.