Impact of Exercise on the Complications of Corticosteroids in Patients With GVHD: the RESTART Trial

This study is about determining if an aerobic and resistance exercise intervention is feasible in patients diagnosed with acute or chronic GVHD (Graft-Versus-Host Disease) after having an allogeneic stem cell transplant. The names of the study interventions involved in this study are: * Aerobic and resistance exercise (A+R) - Home-based aerobic and resistance exercise program * Attention control (AC) - Home-based stretching program

Inclusion Criteria: * Over 18 years old; children under the age of 18 will be excluded due to rarity of disease * Newly diagnosed with acute or chronic GVHD, starting corticosteroids at a dose of .20 mg/kg or greater for the first time since transplant * Received allogeneic stem cell transplant (any conditioning, any donor) at Dana-Farber Cancer Institute * Physician's clearance to participate in moderate-vigorous intensity exercise * Speak English * Currently participate in less than 60 minutes of structured exercise/week * Willing to travel to Dana-Farber Cancer Institute for necessary data collection * Ability to understand and the willingness to sign a written informed consent document. Exclusion Criteria: * Have a plan for hospital admission within the next 13 weeks at the time of recruitment * If patients are not enrolled within 14 days after initial steroid treatment, they will be ineligible * Pre-existing musculoskeletal or cardiorespiratory conditions * Patients should not have any uncontrolled illness including ongoing or active infection, uncontrolled diabetes, hypertension, or thyroid disease * Patients may not be receiving any other investigational agents, or concurrent biological, chemotherapy, or radiation therapy * Patients with other active malignancies * Participate in more than 60 minutes of structured exercise/week * Unable to travel to Dana-Farber Cancer Institute for necessary data collection * Subjects, who in the opinion of the investigator, may not be able to comply with the safety monitoring requirements of the study.