In 6- to 8-year-old children, cardiorespiratory fitness moderates the relationship between severity of life events and health-related quality of life

In children, the pathways by which physical activity and fitness are associated with physical and psychological wellbeing are still not fully understood. The present study examines for the first time in young children whether high levels of cardiorespiratory fitness and physical activity moderate the relationship between severity of life events and health-related quality of life.; Three hundred and seventy-eight children (188 girls, 190 boys, M age = 7.27 years) participated in this cross-sectional study. Parental education, gender, age, severity of life events, health-related quality of life and physical activity were assessed via parental questionnaires. Cardiorespiratory fitness was assessed with the 20 m shuttle run test. Hierarchical regression analyses were used to test whether physical activity and fitness interacted with critical life events to explain health-related quality of life.; When exposed to critical life events, children with higher fitness levels experienced higher levels of psychological wellbeing, relative to their less fit peers. On the other hand, children with higher fitness levels experienced higher physical wellbeing and more positive friendship relationships when severity of life events was low. A similar moderation effect was found for physical activity with overall quality of life as outcome.; Recent stressful experiences alone were not sufficient to explain negative health outcomes in young children. Children with low cardiorespiratory fitness levels experienced lower psychological wellbeing when they were exposed to critical life events. More research is needed to find out whether similar findings emerge with objective physical activity measurements and when critical life events are assessed over longer periods of time.