The length of this study, including screening is approximately 24 months. Patients at Bariatric Surgery Clinics will be recruited for this study. Both patients that decide to undergo bariatric surgery, and those that do not undergo surgery will be enrolled. Patients will be randomized to either a high intensity interval training (HIIT) or standard exercise regimen after eligibility is confirmed and the baseline visit is complete. All patients will complete follow-up appointments at 3 month, 12 months and 24 months. Patients that are randomized to the HIIT program will compete 2 supervised and 1 unsupervised training sessions a week for 24 months.