Self-determination theory (SDT) is a theory of motivation that may provide some insight into why weight loss interventions emphasizing financial incentives have struggled to achieve successful maintenance [21, 22]. At the core of SDT is the concept of autonomous motivation, characterized by feeling free and acting for the sake of rewards that are inherent to the activity itself. This inherent reward could be positive emotions, such as interest and enjoyment (i.e.,intrinsic motivation), or the satisfaction associated with action that is personally meaningful (i.e., identified extrinsic motivation). Importantly, an emerging body of evidence shows that autonomous motivation is positively related to persistence and maintenance of healthy lifestyle changes.
Specifically, self-reported autonomous motivation has been shown to predict greater maintenance of physical activity and weight loss [23, 24]. In a 3-year randomized controlled trial, Silva and colleagues contrasted an intervention designed to promote autonomous motivation for exercise and weight management to a general health education control condition[25–28].
After 3 years, the intervention designed to support autonomous motivation produced significantly better maintenance of both exercise and weight loss, relative to control, and the effects were mediated by autonomous motivation (both intrinsic motivation and identified extrinsic motivation)
[29].