Influence of physical activity on perceived stress and mental health in university students: a systematic review.

University students are a population particularly vulnerable to stress, anxiety, and reduced wellbeing. Physical activity has been proposed as a protective factor, but existing findings are heterogeneous. This systematic review examined the relationship between physical activity and mental health in university students, focusing on perceived stress, anxiety, depression, and psychological wellbeing. It was conducted in accordance with PRISMA guidelines, and the study protocol was registered in PROSPERO (CRD420251179614). A total of 38 studies published between 2020 and 2025 were analyzed, involving more than 20,000 participants from various countries. Most studies were cross-sectional, although some longitudinal and quasi-experimental studies were also included. The results showed a consistent association between higher levels of physical activity and lower levels of stress, depression, and anxiety, as well as an increase in subjective wellbeing. In addition, mediators such as sleep quality and resilience, and moderators such as gender or internet use, were identified. The effects were more significant when physical activity was combined with other healthy habits such as good sleep and low sedentary behavior. Although most of the studies were not experimental, the evidence suggested a possible beneficial causal effect of exercise. The need for comprehensive interventions in universities was highlighted, promoting physical activity as a preventive and therapeutic strategy to improve the mental health of students.