Transcatheter aortic valve replacement (TAVR) is a treatment alternative among high-risk elderly with aortic stenosis, however, mortality remains high. Fifty percent of patients undergoing TAVR exhibit frailty, a syndrome associated with poor survival. It is unknown whether interventions to improve frailty before TAVR (prehabilitation) will improve outcomes after TAVR. This study plans to evaluate whether simple cardiac exercise interventions to improve physical performance before TAVR improves outcomes after TAVR.