Metabolic Adaptations in Response to High Intensity Interval Training in Obese Adults

The overall objectives are to: 1. Assess mechanisms underlying HIIT-induced improvements in insulin resistance at the whole-body, tissue, and cellular levels. 2. Systematically compare different HIIT regimens to help identify effective "doses" of HIIT that may be optimal for improving metabolic health in obese adults. 3. Assess the ability/willingness of obese subjects to adhere to a long-term HIIT program. Findings from these studies will greatly expand knowledge about the effects of HIIT on metabolic health, and will provide valuable information for development of programs aimed at maximizing key metabolic benefits of exercise.

Inclusion Criteria: * Age: 18-40 * Body Mass Index: 30-40 kg/m2 * Waist circumference: 88-98cm for women and 100-110cm for men * No regularly planned exercise/physical activity * Women must have regularly occurring menses and must be premenopausal Exclusion Criteria: * EKG abnormalities as assessed by the cardiologist on the research team * Evidence/history of cardiovascular or metabolic disease * Medications known to affect lipid or glucose metabolism * Pregnant or lactating * Tobacco or e-cigarette use