Background: National recommendations supporting the promotion of multiple short (10+ minute) physical activity bouts each day to increase overall physical activity levels in middle-aged and older adults underscore the need to identify antecedents and correlates of such daily physical activity episodes.
Purpose: This pilot study used Ecological Momentary Assessment to examine the time-lagged and concurrent effects of empirically supported social, cognitive, affective, and physiological factors on physical activity among adults age 50+ years.
Methods: Participants (N = 23) responded to diary prompts on a handheld computer four times per day across a 2-week period. Moderate-to-vigorous physical activity (MVPA), self-efficacy, positive and negative affect, control, demand, fatigue, energy, social interactions, and stressful events were assessed during each sequence.
Results: Multivariate results showed that greater self-efficacy and control predicted greater MVPA at each subsequent assessment throughout the day (p < 0.05). Also, having a positive social interaction was concurrently related to higher levels of MVPA (p = 0.052).
Conclusion: Time-varying multidimensional individual processes predict within daily physical activity levels.