Abstract
BACKGROUND: Physical activity levels remain suboptimal in older adults. Exploration of potentially modifiable factors such as social support is needed to inform the development and implementation of patient-oriented physical activity interventions for older adults. The impact of general health on the relationship between social support and physical activity is not well understood. We aimed to determine the association between social support and self-reported physical activity in a study of community-dwelling older adults. In addition, we examined whether self-reported general health mediates the relationship between social support and self-reported physical activity. METHOD: This cross-sectional study analyzed baseline data collected as part of a randomized controlled trial comparing a digital physical activity intervention, which included social support features, with a tablet-based educational control. Adults ≥ 60 years of age were enrolled at 2 sites. Self-reported general health, social support, physical activity, and sociodemographic characteristics and comorbid conditions were assessed. Pearson and point-biserial correlations were computed to evaluate the relationship between physical activity and general health, social support, and sociodemographic features. Social support (exposure), general health (mediator), and physical activity (outcome) were incorporated into a mediation model. RESULTS: Among 181 participants (mean age of 70.1 years), significant correlations were found between physical activity and both general health and social support (r = -0.19 and r = 0.21, respectively; both p < 0.01). General health significantly mediated the relationship between social support and physical activity (unstandardized ß coefficient 416.9; 95% confidence interval 96.4, 842.0). CONCLUSIONS: Augmentation of social support, particularly when coupled with other modes of health promotion to improve personal wellbeing, may be a valuable component of physical activity promotion programs. Further longitudinal research is needed to clarify the potential mechanistic pathways linking social support, general health, and physical activity to inform development of evidence-based physical activity interventions for older adults and improve downstream health-related outcomes. TRIAL REGISTRATION: ClinicalTrials.gov, ClinicalTrials.gov identifier NCT03538158 . Registered May 25, 2018.