This study investigated the association among loneliness, number of friends, and participation in physical education classes, leisure-time physical activities, and active commuting. Data from 102,072 adolescents participating in the National School-based Health Survey aged 11-19 years were analyzed. Information about the study variables was self-reported through a questionnaire. Adolescents more active in physical education classes and leisure were less likely of having social isolation. Those more active in commuting were more likely of having social isolation. Interventions aimed at addressing social isolation in adolescence can prioritize school and leisure-time physical activities.
Keywords: adolescents; friends; loneliness; physical activity; social isolation.