Allocating in the admission for a supervised exercise program all subjects evaluated with low cardiac vagal tone (cardiac vagal index ≤ 1,30), it is expected that from a sample of almost 150 subjects (all over 18 years-old, ranging mostly from 40 to 50), we will compare 50 subjects that adhered to the supervised exercise program ( more than 65% of expected presence). Patients with pacemaker on unable to exercise in the bicycle will be excluded from the study, as well as those who does not adhere to at least more than 65% of the expected presence in the supervised exercise program.