 - Age 18 and 35; HbA1c 5.7; heart or lung disease; acute systemic infection accompanied by fever, body aches, or swollen lymph glands; BMI 26 kgm2; current dieting or weight loss efforts; current pregnancy or breastfeeding; known history of HIVAIDS; cancer; biochemical evidence of renal or hepatic dysfunction; renal or liver disease; demyelinating diseases such as multiple sclerosis or amyotrophic lateral sclerosis; recent blood donation; clinical history of stroke; hypertension systolic 140 mmHg or diastolic 90 mmHg; type 1 or 2 diabetes; history of keloid formation inability to exercise at 50 of predicted heart rate HR reserve at baseline. Participants taking beta-blockers Participants who screen positive for The American Heart Associations contraindications to exercise testing 