This study explored the relationship between physical activity and depression, and the mediating role of coping styles and loneliness between the two, and found that physical activity can not only directly affect depression, but also indirectly through the separate mediating roles of coping styles and loneliness, as well as the chain mediating role of the two. This further explains why physical activity affects depression, which is important for intervention and prevention of depression in college students.
Physical Activity Effects on depression
It was found that physical activity was negatively and significantly associated with depression. This result is consistent with previous research44 and verifies Hypothesis 1. First, it was shown in neurophysiology that physical activity improves cardiovascular, cerebrovascular, and respiratory function and promotes the release of neurotransmitters such as dopamine, 5-hydroxytryptophan, and endorphins, which improves psychological states such as tension, anxiety, and restlessness. Secondly, when engaging in physical activities, individuals can not only effectively relieve negative emotions, but also receive encouragement and support from peers, and develop self-will quality and improve interpersonal communication. In addition, Physical activity also has a significant effect on enhancing positive emotions such as self-efficacy, resilience, and cooperation and competitiveness among college students, which in turn alleviates or reduces depression.
Coping style independent mediator effect
The present study found that coping styles mediated the relationship between physical activity and depression, validating Hypothesis 2. This is consistent with research evidence that physical activity helps to enhance coping styles18, and that coping styles help to alleviate depression.
On the one hand, individuals with high-level of physical activity demonstrate positive coping skills. According to the Health Action Process Orientation Theory, physical activity stimulates an individual’s ability to self-manage and self-monitor, thereby raising mental health. In the face of stress, pressure or negative events, individuals with a high-level physical activity tend to adopt the behavior pattern of holding optimistic beliefs, showing a calm approach to problems and choosing problem-solving oriented coping strategies. Conversely, those college students with lower-level physical activity endure relatively less psychological stress and present lower-level self-control in the face of stressful events, and individuals may be less volitional in their efforts and prone to negative emotions, with a tendency to opt for negative approaches such as moodiness, denial, fantasy, and avoidance16.
On the other hand, positive coping styles predict the occurrence of depression. When college students face stress, by adopting a problem-solving-oriented positive coping style and by adjusting their mindset, emotions, and cognition, individuals will actively seek help to reduce negative consequences, thus avoiding the emergence of depression. On the contrary, immature and negative coping styles may cause negative emotions such as anxiety, fear, self-blame, and frustration, individuals show confusion and adopt unreasonable or ineffective methods when dealing with events, and lack of active change makes it difficult to get rid of difficulties, which may induce depression.
Independent mediating effects of loneliness
The present study found that loneliness mediated the relationship between physical activity and depression, validating Hypothesis 3. This is consistent with previous research evidence that physical activity negatively predicts loneliness7 loneliness positively predicts depression.
On the one hand, physical activity could negatively predict loneliness. In the process of physical activity will face some pressure and challenges, peer or social mutual encouragement and support can increase mutual trust and friendship between students, and through the recognition of classmates, in the activities to enhance self-worth, and thus reduce the sense of isolation. Due to the rapid development of artificial intelligence and the internet, physical activities have been replaced by social media, and sedentary time and screen behavior have increased, making people ignore real interpersonal communication, thus increasing the risk of loneliness.
On the other hand, loneliness positively predicts depression. Based on interpersonal theories, Individuals who are excluded from the outside world during interactions can trigger loneliness further producing depression, social withdrawal and other behaviors to occur. College students are in the stage of immature mind but very strong self-consciousness, they are highly concerned about their status and image in social occasions and attach importance to others’ evaluation of them. When this need is not met, loneliness and depression and distress can occur. This kind of emotional state can easily bring about subjective perception of the difference between actual social relations and expectations, thus causing negative emotional reactions and leading to depression.
The chain-mediated effect Coping styles and Loneliness
Based on the above studies, a chain mediation model was constructed to explore the process and mechanism of physical activity and depression. Coping style and loneliness play a chain mediating role between physical activity and depression. Specifically, physical activity is conducive to improving coping style. High-level coping style is an important factor in predicting loneliness, and loneliness is a further predictor of depression. This confirms Hypothesis 4 of this study.
An individual’s mental health and emotional regulation depends largely on coping styles. Effective coping with stressful situations can lead to positive emotional experiences, such as happiness, self-confidence. Conversely, ineffective coping can lead to depression and feelings of isolation. According to stress theory of physical exercise, physical activity, which is characterized by hardship, fatigue, and competition, plays an important role in developing the qualities of resilience, self-confidence, bravery, and resourcefulness, as well as contributing to the formation of mature and stable personality traits among college students, which leads to the development of coping styles that are positively protective of psychological well-being. When facing academic pressure, life pressure or other setbacks, college students with good coping styles are not only able to be problem-solving oriented, but also take the initiative to seek the support and help of others to get through the difficult situation, so as to make life more meaningful.Individuals with low-level physical activity tend to be isolated and have negative emotions, which further negates self-denial and reduces the sense of social value and leads to loneliness.
Therefore,physical activity is positively correlated with the coping style level among college students, which helps to improve individual emotional experience and life satisfaction, thus alleviating or reducing loneliness. In addition, individuals with lower-level loneliness were more likely to communicate with classmates, develop positive confidence, and contribute to improved mental health and reduced depression.
practical significance
This study explored the effects of physical activity on college students’ depression, enriched the research on the correlation between physical activity and the field of depression, and is of practical significance in preventing or alleviating college students' depression. First, colleges should emphasize physical activity as an important antecedent variable in preventing or alleviating depression. Secondly, the result that coping style and loneliness play a mediating role between physical activity and depression suggests that educators should pay attention to the important influence of these two factors on the depressive state of college students, and pay attention to improving their coping style and reducing their loneliness.
Limitations and Prospects
In this study we were unable to infer the causal relationship between variables. Longitudinal follow-up or experimental intervention designs can be adopted in the future. In addition, in this study we considered only the mediating effects of coping style and loneliness. In fact, there may be other mediating variables, such as self-control and meaning in life, which need to be further explored.