Inclusion Criteria:  Age 18 and older Able to speak English Ambulatory [assistive devices ok] Preoperative Anesthesia and Surgical Screening (PASS) clinic patient with DASI score <34 Able to provide informed consent  Exclusion Criteria:  Acute myocardial infarction (3-5 days) Unstable angina Severe untreated arterial hypertension at rest (>200 mm Hg systolic, >120 mm Hg diastolic) Resting heart rate > 120 bpm Room air desaturation at rest on room air <85% Inmate of correctional facility (i.e. prisoner) Diagnosed history of dementia Inability to ambulate independently Considered inappropriate to participate by Principal Investigator