Physical Activity and Variation in Momentary Behavioral Cognitions: An Ecological Momentary Assessment Study.

Abstract

Decisions to perform moderate-to-vigorous physical activity (MVPA) involve behavioral cognitive processes that may differ within individuals depending on the situation. Ecological momentary assessment (EMA) was used to examine the relationships of momentary behavioral cognitions (ie, self-efficacy, outcome expectancy, intentions) with MVPA (measured by accelerometer). A sample of 116 adults (mean age, 40.3 years; 72.4% female) provided real-time EMA responses via mobile phones across 4 days. Multilevel models were used to test whether momentary behavioral cognitions differed across contexts and were associated with subsequent MVPA. Mixed-effects location scale models were used to examine whether subject-level means and within-subjects variances in behavioral cognitions were associated with average daily MVPA. Momentary behavioral cognitions differed across contexts for self-efficacy (P = .007) but not for outcome expectancy (P = .53) or intentions (P = .16). Momentary self-efficacy, intentions, and their interaction predicted MVPA within the subsequent 2 hours (Ps < .01). Average daily MVPA was positively associated with within-subjects variance in momentary self-efficacy and intentions for physical activity (Ps < .05). Although momentary behavioral cognitions are related to subsequent MVPA, adults with higher average MVPA have more variation in physical activity self-efficacy and intentions. Performing MVPA may depend more on how much behavioral cognitions vary across the day than whether they are generally high or low.