Contextual influences on the within-person association between physical activity and affect in adolescents: an ecological momentary assessment study.

There is limited research on how the context in which moderate-to-vigorous physical activity (MVPA) occurs influences the relationship between physical activity and affect. This study aimed to investigate how the social context and physical environment enhance the relationship between MVPA and affect in daily life. Overall, 119 adolescents (mean age = 14.7 years) provided information about their core affect, physical environment and social context on multiple occasions over a 4-day period using ecological momentary assessment. Additionally, participants' level of MVPA was objectively measured using accelerometers. Level of MVPA was positively associated with energetic arousal, being outdoors was positively associated with valence and energetic arousal, and being with someone else was also positively associated with energetic arousal. Additionally, being outdoors moderated the association between MVPA and tense arousal so that MVPA was only inversely related to tense arousal when outdoors. These findings showed that young people experience more positive valence, greater levels of energetic arousal and less tense arousal when physically active outdoors compared to when indoors and highlight the importance of encouraging young people to participate in physical activity outdoors. Further research is warranted to understand how social contexts may influence the association between MVPA and affect in young people.