Objectives: to assess longitudinal relationships between habitual levels of physical activity and indices of psychological wellbeing in older people.
Design: baseline assessment with 4- and 8-year follow-ups.
Subjects: 1042 people originally aged 65 and over randomly sampled from general practitioner lists in Nottingham, UK.
Methods: logistic regression analysis of selected T1 (1985) and T2 (1989) variables, with depression at T2 as dependent; multiple regression analyses of selected T1, T2 and T3 (1993) variables, with life satisfaction at T2 (model 1) or T3 (model 2) as dependent.
Main outcome measures: questionnaire-assessed levels of physical activity; 14-item Symptoms of Anxiety and Depression scale; 13-item Life Satisfaction Index; health, demographic and social activity variables.
Results: in the logistic regression model, depression at T2 was most strongly associated with depression [odds ratio (OR) = 7.13; 95% confidence interval (CI) = 3.25-15.64; P < 0.001] and lower physical health status (OR = 1.26 per unit change in score; 95% CI = 1.17-1.42; P < 0.001) at T1. Lower levels of outdoor/leisure activities at T1 were also associated with some increased risk of depression 4 years later (OR = 0.92 per hour of activity; 95% CI = 0.85-0.99; P < 0.05). Similar predictive patterns emerged from the multiple regression analyses where, in both models, earlier levels of life satisfaction, social engagement and health accounted for most of the explained variance in life satisfaction (R2 = 0.42 for model 1; R2 = 0.35 for model 2). Again, however, earlier levels of physical activity (as walking and housework) did contribute significantly, although modestly, to longitudinal changes in morale.
Conclusions: while the results provide some support for the conclusion that physical activity contributes independently to the promotion and maintenance of psychological wellbeing in later life, this contribution is, at best, extremely modest.