Exercise for Women With Peripheral Arterial Disease

Inclusion Criteria: * women 60 years of age and older having a positive history of intermittent claudication assessed by the San Diego Claudication Questionnaire * exercise limited by intermittent claudication during a screening treadmill test using the Gardner protocol * an ankle/brachial index (ABI) \< 0.90 at rest or \< 0.73 immediately following the treadmill exercise test * at least one year past menopause Exclusion Criteria: * absence of PAD (peripheral artery disease) * asymptomatic PAD (Fontaine stage I) * rest pain due to PAD (Fontaine stage III) * tissue loss due to PAD (Fontaine stage IV) * medical conditions that are contraindicative for exercise according to the American College of Sports Medicine (e.g., acute myocardial infarction, unstable angina, etc.) * use of medications indicated for the treatment of intermittent claudication (cilostazol and pentoxifylline) initiated within three months prior to investigation) * cognitive dysfunction (mini-mental state examination score \< 24) * active cancer, renal disease, or liver disease * a calf skin fold measurement \> 50 mm, because of potential interference with the light path of the near-infrared spectroscopy probe from penetrating the subcutaneous tissue * pulse arterial oxygen saturation of the index finger \< 95% because of the potential deleterious effect on calf muscle StO2 from poor pulmonary gas exchange