Strength training in a cardiac rehabilitation program: a six-month follow-up.

The effect of circuit training on blood pressure (BP) and strength were evaluated for six months in 16 middle-aged (means = 55.8 years) men in a metropolitan cardiac rehabilitation program. Circuit training consisted of 12 to 20 repetitions at 30% to 40% of one repetition maximum on 12 Nautilus exercises with one-minute rests between exercises. This strength conditioning was supplemental to the patients' aerobic exercise. Five of the patients had myocardial infarctions, six had coronary artery bypass grafts, two had ventricular arrhythmias, one had angioplasty, and two had a complex of other cardiac conditions. Average height, weight, and body fat for the 16 patients were 179.3 cm, 82.4 kg, and 24.6%, respectively. Blood pressure (BP) data indicated no change in mean systolic or diastolic values during actual circuit training sessions (initial = 122/77 mmHg, mid = 124/78 mmHg, end = 122/76 mmHg). These data were compared with corresponding sets of BP at three and six months of training and no significant differences were seen. In no instance did circuit training appear to elevate a patient's BP above clinically acceptable levels for controlled hypertension. In the six months, significant increases in strength were observed with a mean increment of 8.2 kg or 22% for all 12 exercises. No changes occurred in body weight or percentage of fat. For selected patients in cardiac rehabilitation programs, a carefully supervised, long-term program of low-resistance strength training appears to be safe with regard to BP response, and beneficial in terms of strength gain.