The Role of Mood and Stress in Physical Activity Engagement: Insights from Ecological Momentary Assessment

BackgroundRegular physical activity (PA) comes with a multitude of benefits. However, most of them only become apparent after some time, while motivational ‘costs’ (e. g., exertion or fatigue) are immediate. Therefore, PA engagement requires individuals to overcome immediate costs in favor of longer-term benefits. The capacity to achieve that, however, seems to fluctuate and may depend on current context and momentary affect. Therefore, this Ecological Momentary Assessment (EMA) study prospectively examined the temporal relationship of momentary affect with PA intentions and consecutive PA engagement on a within-person and intra-day level.Methods41 healthy participants (aged 19-67) responded to 4 daily EMA prompts throughout 3 weeks capturing momentary mood, stress, anticipated barriers (PA incompatible external circumstances), and intentions for subsequent PA as well as PA behavior (since the last prompt). We applied generalized linear mixed effect models to examine the associations between these variables.ResultsAs expected, happy and active moods were positively associated with PA intentions, while relaxed and tired moods showed a negative association. Surprisingly, stress was positively associated with subsequent PA intentions. None of the affective states showed direct associations with actual PA behavior.ConclusionsOur study is among the first to provide a prospective window into fully contextualized, in-situ PA intention formation and enactment under naturalistic conditions. As hypothesized, high energetic and positive mood states facilitated PA intention formation and should be targeted in interventions. Stress, however, might also facilitate the formation of PA intentions, potentially as part of a stress coping strategy. Generally, these results inform dynamic health behavior theories and provide a departure point for contextualized and adaptive interventions such as Just-in-Time Adaptive Interventions.