- Medical History: a) recent hospitalization (less than 3 months prior to study entry) for severe medical disease, b) peripheral arterial disease with vascular claudication, c) orthopedic or chronic pain condition restricting exercise, d) pulmonary or renal failure, e) active cancer, f) untreated poorly controlled hypertension measured on at least 2 occasions (greater than 190/100) g) untreated and / or poorly controlled diabetes with fasting blood glucose of greater than 170 and HbA1c greater than 10.0, h) medications: heparin, warfarin, lovenox, apixaban, dabigatran, rivaroxaban, and oral steroids, i) currently pregnant