Relationship of the number of days of participation in school physical education classes in a week with body mass index, number of hospital treatments for school violence, and mental health status among Korean male adolescents

School sports activities may help address obesity, school violence and mental health issues, which can be considered the biggest issues related to adolescents. However, previous research has not examined the relationship between participation in school physical education classes and obesity, school violence and mental health among adolescents by focusing on the number of days adolescents participate in school physical education classes. Therefore, this study investigated the association of the number of days of participation in physical education classes in a week with body mass index, number of hospital treatments for school violence, and mental health status among Korean male adolescents. Data of 25,749 male Korean adolescents were collected from the 2022 Korea Youth Risk Behavior Survey. Data collected were analyzed using frequency analyses, chi-square analyses and multivariate logistic regression analyses. The results showed that the more Korean male adolescents participate in physical education classes in a week, the more likely they are to become healthy, overweight and obese. The more they participate in physical education classes in a week, the less often they are treated in hospitals for school violence. The more they participate in school physical education classes in a week, the less likely they are to experience suicidal ideation but more likely to feel lonely. Overall, increasing the number of physical education classes can help solve adolescents' health problems, but they must participate actively and voluntarily in the classes. Efforts must be made to increase their active and voluntary participation.