How affective and instrumental physical activity outcomes are associated with motivation, intentions, and engagement...

Physical activity (PA) produces various outcomes, including affective responses and instrumental benefits (e.g., weight loss, health). Theories of behavioral maintenance suggest that decisions to continue PA engagement will depend on one's satisfaction with received outcomes. Thus, this study was designed to test how different combinations of affective and instrumental outcomes influence motivation, intentions, and subsequent PA behavior over a two-week study period. Participants with weight loss goals (N = 119) were provided an exercise video that was designed to manipulate their affect while exercising (positive vs. neutral) and their beliefs about the video's instrumentality for weight loss (instrumental vs. not). Self-report measures assessed participants' affect while exercising, instrumental beliefs that the video would produce weight loss, and motivation and intention to exercise with the video for two weeks. After two weeks, participants reported their video use. Because initial pre-registered analyses revealed that the video manipulation did not produce a difference in affect, a regression-based approach was implemented to examine whether variability in self-reported affect while exercising and beliefs about the video's effect on weight loss predicted motivation, intentions, and video use during the two-week study period. Reports of more favorable affect were positively associated with motivation and video use, regardless of instrumental beliefs. For those reporting less favorable affect, strong instrumental beliefs appeared to bolster motivation, but had an adverse effect on video use. Findings provide insight into how different types of PA outcomes might influence motivation and continued behavioral engagement.