Exercise prescription for cardiac patients. Reasons for concern.
D001145:Arrhythmias, Cardiac / Q000209:etiology; D005080:Exercise Test; D005081:Exercise Therapy; D006331:Heart Diseases / Q000534:rehabilitation*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D012306:Risk; D013997:Time Factors; D014693:Ventricular Fibrillation / Q000209:etiology