The American Association (AHA) has issued a scientific statement advisory (Circulation 2000; 101: 828-833) stating that resistance training (weight training) should be incorporated into the exercise regimens of healthy adults and many patients at low to moderate cardiac risk. Its safety in higher risk patients, such as those with unstable angina, uncontrolled hypertension, uncontrolled arrhythmias, heart failure, and severe valvular disease, has not been established.
The statement was based on evidence that weight training can favorably modify several risk factors for heart siease, including lipids and cholesterol levels, blood pressure, body fat levels and glucose metabolism. In addition, resistance training offers development of greater muscle strength and is helpful in the prevention of falls, osteoporosis, sarcopenia, and diabetes.
In the past, the AHA has focused its exercise recommendations primarily on aeorbic, or endurance activities. These activities in which people continously move large muscle groups. The AHA now states that the optimal regimen for decreasing cardiovascular risk combines aerobic exercise with resistance training or slowly moving muscles against resistance supplied by weight. Resistance training does not reduce resting heart rate as does aerobic activity. It does, however, lessen elevations in heart rate and blood pressure that occur when people lift heavy objects, improve muscle endurance and strength, and facilitate weight loss by increasing the muscle-to-fat ratio.
The AHA prescription for pumping iron suggests that patients start with eight to ten resistence exercises that work the front and back of major muscle groups (e.g., chest/back and biceps/triceps) two or three days a week. Healthy people younger than 50 should perform eight to twelve repetitions of each exercise. Patients should lift enough weight to challenge themselves without inducing pain. Once the repetitions can be done without fatigue, the weight should be increased. Older individuals and those with heart disease should use lighter weights and do more repetitions (10 to 15). For older adults, weight machines which guide and limit the range or motion, may be safer because they prevent balance problems, dropping of weights and low back pain. Patients with cardiac disease need less vigorous programs. Consult your physician for more information.