Exercise Preconditioning to Protect Against Dialysis-induced Cardiac Injury

The goal of this study is to determine what happens to the heart muscle contraction when people cycle before their hemodialysis treatment. Will pre-dialysis exercise protect the heart from a decrease in pumping of the heart muscle (called stunning) that can happen during hemodialysis. We will study whether pre-dialysis exercise decreases heart stunning, decreases the number and severity of symptoms commonly associated with hemodialysis, and other outcomes