Exercise Dose-Response on Features of the Metabolic Syndrome

Inclusion Criteria: * Males or females, age 18-60 * At least 2 of the 5 components of the NCEP definition of the metabolic syndrome, provided that either the triglyceride or waist circumference criteria are met * Body mass index of 25-45 kg/m2 * Subjects not currently following a regular exercise program nor an optimal diet, and who self-report their activity level as sedentary * Able to understand and sign the informed consent form, follow the instructions given in the study, attend all necessary clinic visits, and undergo all required study procedures Exclusion Criteria: * Past or current diabetes mellitus * Significant concurrent medical illnesses (chronic liver or renal disease, malignancies, recent or chronic infections including HIV, surgeries or other hospitalizations within four weeks prior to screening), uncontrolled hypertension (BP \>160/90 mm Hg), or abnormal TSH on screening. * Conditions that may contraindicate physical activity (clinically significant cardiac, pulmonary, orthopedic, rheumatological or neurological diseases) * Cardiovascular disease not controlled with medical therapy, or invasive vascular procedures within six months prior to screening * Subjects found on resting EKG or stress testing to have underlying cardiac abnormalities * Perimenopausal women who are experiencing irregular menses * Pregnant or lactating women * Subjects who may have limited exercise tolerance because of treatment with β-adrenergic blockade agents, at least until agents of alternate drug classes can be substituted * Subjects with concurrent endocrinopathies * Subjects receiving concurrent treatment with metformin, thiazolidinediones, systemic glucocorticoids, or any weight loss agents * Subjects who expect to require medications during the course of the study that may affect their metabolic profile, including systemic glucocorticoids and hormone replacement therapies * Subjects who cannot complete the stress test due to physical limitations * Any other factors that, in the opinion of the investigators, may interfere with the safe conduct, the successful completion, or the quality of the data obtained from the study