The mobile phone dependence of college students has gradually become a common and serious problem in society. Physical activity constitutes an important intervention to ameliorate this phenomenon. Previous studies have found that self-control can effectively reduce dependence on mobile phones. Therefore, it is necessary to consider whether physical activity can improve self-control and reduce college students' mobile phone dependence. In total, 418 college students were selected by means of convenience sampling. The Physical Activity Rating Scale (PARS-3), the College Student Phone Dependency Questionnaire, and the College Student Self-Control Scale (SCS) were distributed electronically. The results show that 1) physical activity has a negative effect on college students' mobile phone dependence, 2) physical activity plays a positive role in the self-control of college students and 3) self-control plays a mediating role in the effect of physical activity on mobile phone dependence. Physical activity is an effective intervention for decreasing an individual's mobile phone dependence, and self-control acts as a mediator to reduce mobile phone use. KeywordsPhysical activity . Self-control . Mobile phone dependence . Mediating effect . College students Mobile phones have become a significant component of our daily life due to their multifunctionality. The current statistics show that the number of mobile phone users in China has reached 1.59 billion (Ministry of Industry and Information Technology of the People's Republic of China 2019). Mobile phones provide convenient methods for payment, shopping,

Mental simulation, which employs specific patterns of imagery, can increase the intention to exercise as well as actual engagement in exercise. The present studies explored the effects of mental simulation on the intention to engage in exercise while regulating emotions. The first study confirmed that mental simulation did promote intentions of participants. The second found that video-primed mental simulation was a more effective method of exercise intention promotion than semantic-primed and image-primed mental simulation. In the third study, it was found that combining process-based and outcome-based mental simulations increased exercise intentions. Positive emotions mediated imagery ability and intention to exercise. The final study found that the mental simulation interventions most effective for exercise adherence were those that balanced the valence of process and outcome components in such a way that a challenging process results in a positive outcome, or a smooth process results in a negative outcome. Each of these results has practical implications for exercise interventions that will be discussed.