Daily self-efficacy, planning and social support explain leisure-time physical activity in working adults: evidence for the cultivation hypothesis from an ambulatory assessment study.

Background: Identifying theory-based, modifiable processes and resources in everyday life is essential for improving physical activity levels, and leisure-time physical activity (LTPA) especially. Deconfounding different sources of social support for day-to-day LTPA, we examined effects of LTPA-specific received support from both private and work domains. Furthermore, we investigated whether daily intrapersonal processes - such as positive affect, self-efficacy, and planning - are linked with LTPA through cultivating social support. Methods: A total of 118 adults ( Results: On average, participants received more LTPA-specific support from the private compared to the work domain. Having received higher-than-usual social support from family/friends on a day was consistently linked to higher LTPA. No such within-person effect emerged for support from colleagues/supervisors. On days with higher-than-usual self-efficacy and planning, participants performed more LTPA, whereas positive affect was unrelated to LTPA at the within-person level. These results were found for both device-assessed and self-reported LTPA. Within-person mediation analyses revealed that between 16%-22% of the effects from self-efficacy and planning to device-assessed/self-reported LTPA were mediated by social support from family/friends. Conclusions: Our results identify intrapersonal and private-domain social exchange processes as potential targets for future ecological momentary interventions. Consistent with the cultivation hypothesis, we also identified that daily self-efficacy and planning were linked to LTPA via social support from family/friends.