Exercise, Brain Activity, and Weight Maintenance

Inclusion Criteria:

* Age 18-70 years
* Body mass index (BMI) \>19 kg/m2 and body weight\< 250kg
* Participants must have experienced a clinically significant weight regain, defined as over 10% of their maximum weight lost, within 1 to 5 years following their bariatric surgery. They will be asked to self-report their weight loss history. Participants must also provide the operative report from their bariatric surgery for reference.
* In good general health with no conditions that could influence the outcome of the trial, and in the judgment of the investigator is a good candidate for the study based on review of available medical history, physical examination and clinical laboratory evaluations
* Willing to adhere to the protocol requirements for the duration of the study

Exclusion Criteria:

* Type 1 diabetes mellitus
* Peripheral neuropathy with insensate feet
* Recent blood donation within the last 2 months
* Use of beta-blockers
* Current pregnancy or breastfeeding
* Active Heart or lung disease
* Severe hypertension (systolic \>160 mmHg or diastolic \>90 mmHg)
* Inability to exercise for any reason
* Any known contraindication to exercise testing based on current ACSM guidelines
* MRI contraindications, such as presence of pacemakers, aneurysm clips, artificial heart valves, ear implants, metal fragments, or foreign objects in the eyes, skin, or body
* Known presence of a structural brain lesion (e.g. tumor, cortical infarct)
* Presence of another neurologic disorder, which could impact findings (e.g. multiple sclerosis)
* History of cardiovascular disease, stroke, congestive heart failure
* Active hematological, renal, pulmonary or hepatic disorders
* Active treatment for cancer
* A history of active alcohol or substance abuse
* Any significant systemic illness or unstable medical condition which could lead to difficulty complying with the study protocol
* History of claustrophobia and inability to tolerate an MRI
* Body weight \>250kgr and largest body diameter of 70cm as there is a certain weight and diameter limit of the MRI scanner
* Unwilling or unable to return for study visits, undergo neuropsychological testing and MRI imaging
* Left-handedness