Date of Submission



Mental ill-health is the leading cause of disability worldwide due to the high prevalence of mental health disorders and the reduced quality of life that accompanies a diagnosis. Alarmingly, many mental health disorders first originate during adolescence, causing a particularly high prevalence amongst young people. Abundant evidence demonstrates that physical activity benefits adults’ and adolescents’ mental health and wellbeing. However, little is known about the specific circumstances under which physical activity optimally promotes mental wellbeing. Without such understanding it is impossible to optimally promote mental health and prevent mental ill-health through physically active behaviours. Limited evidence suggests that leisure-time physical activity is more beneficial to mental health and wellbeing than physical activity during other life domains. It has been suggested that leisure-time physical activity may be a more self-determined behaviour compared to physical activity during other domains, and that this higher quality motivation may explain why leisure-time physical activity is more strongly associated with improved wellbeing. However, the role motivation plays in the relationship between domain-specific physical activity and mental health has not yet been examined.


Institute for Positive Psychology and Education

Document Type


Access Rights

Open Access


267 pages

Degree Name

Doctor of Philosophy (PhD)


Faculty of Health Sciences