Project Impact: An Innovative Approach to Weight Loss Maintenance

Most adults who engage in lifestyle modification find it difficult to maintain a high level of PA over the long-term, and most also find that weight regain is inevitable. The current portfolio of available interventions does not adequately address these challenges. This project is designed to test the effectiveness of an intervention that is specifically designed to enhance the ability to maintain, in the long-term, a level of PA high enough to achieve long-term weight loss maintenance. In the study, 300 obese adults will be recruited from the community and provided with 6 months of group-based, standard behavioral treatment for induction of weight loss (Phase I). A 6-month Phase I was chosen so that all participants will have sufficient time to accomplish initial weight loss before Phase II begins, allowing Phase II to truly be a test of weight loss maintenance. In Phase II, participants will receive one of three interventions, to be delivered for an additional 12 months: 1) behavioral treatment, with the standard emphasis on maintaining changes in diet and PA (BT), 2) behavioral treatment, with a primary emphasis on using these skills to maintain PA (BT-PA), or 3) acceptance-based behavioral treatment, with a primary emphasis on using these skills to maintain PA (ABT-PA). Assessments will be conducted at baseline, 6 months, 18 months (end of treatment), 24 months (6-month follow-up), and 36 months (18-month follow-up).