Those, who were ≥ 80 years and < 20 years, unable to perform exercise caused by other non-cardiac disease, pregnant, future cardiac transplantation within 6 months, uncompensated HF patients, pacemaker patients, and renal patients with estimated glomerular filtration rate < 30 ml/min/1.73m2, were not candidates in the study. Patients had absolute contraindications for cardiopulmonary exercise test (CPET) and aerobic activities, suggested by the American College of Sports Medicine (ACSM), were also excluded in the study.