Importantly, the proposed intervention is specifically designed to support the subsequent development of an intervention program that is not only feasible, but easy to implement by individuals motivated to achieve a positive health behavior change. A key factor will be the insights gained into stress as a mechanism that counteracts implementation and maintenance of behavior change. This is especially important given the central role of stress in negative health outcomes associated with lack of physical activity, such as poor sleep, negative mood, and chronic low-grade inflammation.