Before undertaking an exercise program, a person should have a physical examination by a doctor, to establish that he or she can participate in this kind of activity without adverse effects. The program should be designed around the person's work capacity, to estimate the intensity of training needed to get this person into good condition. Work capacity can be determined in several ways. The most accurate method is to determine the maximal oxygen uptake (VO6 max), the greatest rate at which oxygen is utilized during work. This test requires special and expensive equipment, so work capacity is usually measured by other techniques that are simpler to perform. Exercise tests using the treadmill or bicycle ergometer are the most common methods of indirectly measuring work capacity, because of their value for medical clearance.
Once physical work capacity has been determined, the amount of exercise needed to get a person into shape can be computed. Generally, an exercise program should approximate 70 to 75% of VO6 max. Physical activity can also be prescribed by training heart rate, which is related to work intensity. The formula for calculating training intensity from heart rate is as follows: Lower conditioning HR = (maximum HR ç resting HR) ? 60% + resting HR; upper conditioning HR = (maximum HR ç resting HR) ? 80% + resting HR.
The three components of a good exercise program are the warm-up period, the aerobic exercise period, and a cool-down period. A warm-up is very important to prevent injuries, because it brings blood to the muscles, readying them for exercise, whether it is walking, running and jogging, cycling, swimming, or playing a sport. A warm-up should include stretching and flexibility moves, to prevent tears in the muscles and tendons.
An exercise program should slowly work the individual into shape. How much exercise is enough and what type is best for developing and maintaining fitness depend on the starting condition of the individual. In general, the exercise should be done every other day, and should bring the target heart rate to between 60 and 90% of the maximal heart rate reserve. The activity should be performed continuously at the proper intensity for 15 to 60 minutes per exercise period.
The mode of exercise or the type used during training should involve large muscle groups, those of the legs and upper body. Such exercise should be maintained continuously and should be rhythmical and aerobic in nature. Examples are running/jogging, walking/hiking, swimming, skating, bicycling, aerobics, and bench stepping.
Active, healthy individuals under 40 and persons under 60 with a low cardiovascular risk profile and normal results from an exercise test can follow a self-regulated program with general guidelines for training. The intensity of exercise should be limited to prevent undue fatigue, and each person can set his or her own limits. Faintness or nausea during or immediately after exercise indicates that an activity is excessive. For most sedentary individuals almost any exercise will provide conditioning, but the activity should preferably be done at a regulated pace over a period of time. This includes brisk walking, jogging, swimming, aerobics, biking, tennis, and golf.
People with major cardiovascular risk factors or abnormal results on stress testing or persons over the age of 60 should be supervised during the initial months of an exercise program, to be sure they are following a healthy program. Once a certain level of fitness is established, they can continue to exercise without supervision. Patients with established cardiovascular disease and patients recovered from myocardial infarction or coronary bypass should follow a supervised adult fitness cardiac rehabilitation program.