Physical activity and psychological distress: moderation by age in two Finnish cohorts 2017–2022

Abstract Background The role of age in moderating the association between physical activity and mental health remains unclear. The present study investigates how age moderates the prospective associations between different intensities of leisure-time physical activity (LTPA) and psychological distress. Methods The study was conducted on survey data from 2017 and 2022 from two cohorts of the Finnish Helsinki Health Study: the working aged employees’ and the ageing employees’ cohort (n = 8307). The working-aged employees were 19-39 years old and the ageing employees 55-75 years old in 2017. LTPA (2017) was measured as metabolic equivalent (MET)-hours across three intensity levels (light, moderate, vigorous). Psychological distress (2022) was measured using the emotional well-being subscale from the RAND-36 questionnaire. General Linear Models were used to examine whether age moderates the association of LTPA with psychological distress. The models were adjusted for baseline psychological distress, sociodemographic factors and health related behavior. Results After adjustments, higher moderate LTPA was associated with less psychological distress, B = -0.02, t =-2.1, p = .036. Similarly, higher vigorous LTPA was associated with less psychological distress, B = -0.02, t =-2.0, p = .041. The associations between higher moderate and vigorous LTPA and lower psychological distress strengthened with increasing age (B = -0.03, t =-3.3, p = .001 for moderate; B = -0.02, t =-2.3, p = .021 for vigorous). Conclusions Moderate and vigorous LTPA appear beneficial for managing psychological distress, with the benefits of both potentially increasing with age. Therefore, age should be considered when designing physical activity interventions aimed at supporting mental health. Key messages • Ageing moderates how leisure-time physical activity is related to mental health. • The importance of moderate and vigorous physical for maintaining mental health might increase with age.