Physical activity and loneliness interrelations with retirement status, health, and personality factors: a theory-based study.

Objectives: Grounded in two theories, Evolutionary Theory of Loneliness/Feedback Model of Loneliness and Continuity Theory of Normal Ageing, primary objective of this study was to examine the longitudinal potentially bidirectional associations between loneliness and physical activity (PA) in later life. Three hypotheses were tested: (1) Loneliness and changes in PA are significantly associated over time when retirement status and partnership are controlled for; (2) Loneliness is correlated with PA, health, retirement, and personality factors; and (3) PA is correlated with loneliness, health, retirement, and personality factors. Design and methods: Data were drawn from a population-representative German cohort ( Results: The proportion of physically active individuals increased over time (T1: 53.8%, T2: 58.6%, T3: 66.4%). Bivariate analyses supported Hypothesis 1, indicating a significant association between loneliness and PA over time. However, multivariate models revealed that health status was the strongest correlates of both loneliness and PA. After adjusting for health, partnership, and personality traits, PA is no longer significantly correlated with loneliness over time, partially supporting Hypothesis 2. Similarly, loneliness was not correlated with PA when controlling for past PA and health, offering partial support for Hypothesis 3. Conclusion: These findings underscore the central role of health in understanding patterns in older adults. Prior engagement emerged as strongest correlate of continued activity, while personality traits particularly lower neuroticism and higher extraversion and conscientiousness were associated with reduced loneliness. Interventions should therefore prioritize the early promotion of physically active lifestyles integrated with loneliness preventing behaviors and cognitions.