How multiple motives facilitate decisions to exercise in contexts with tempting alternatives: evidence from two scenario studies.

Objective: Both affectively-charged and reflective motivation may be necessary to sustain recommended physical activity (PA) guidelines, especially in contexts with tempting alternatives. However, our understanding of how different sources of motivation facilitate PA across contexts is limited. This paper presents a novel value-based model that specifies how affectively-charged and reflective motivation interact to support PA decisions based on available alternatives at a given decision point.

Methods and measures: Two scenario studies tested model assumptions by examining one's general intrinsic motivation for PA (form of affectively-charged motivation), and the reasons one would think of to motivate their PA when faced with alternatives with varying levels of temptingness.

Results: In less tempting scenarios, intrinsic motivation was positively associated with selection of affective reasons (Study 1). In more tempting scenarios, instrumental reasons were generally selected, although the specific type of reason differed based on intrinsic motivation (Study 2).

Conclusion: Findings suggest that instrumental reasons, which motivate behavior through reflective processes, may be particularly important for people when faced with highly tempting alternatives or if they do not find PA to be intrinsically rewarding. More research is needed to determine whether these patterns of motive selection effectively facilitate behavior.