A good overall fitness program has three major components: aerobic activity for cardiovascular endurance and fat burning, anaerobic activity to build strength (both described in detail in the next chapter), and flexibility training to increase your range of motion and lower your risk of injury.

To improve your cardiovascular system, increase your metabolism, burn body fat, and build endurance, try aerobic physical activities such as brisk walking, running, bicycling, swimming, line dancing, hiking, or cross-country skiing, to an extent that brings you into your target heart zone (50 to 85 percent of your maximum heart rate).

A low- or no-impact aerobic activity that you can sus¬tain for at least thirty minutes a day is recom¬mended for those who want to lose weight. To build muscle strength, tone up, promote leaner body mass, and increase bone density, try anaerobic routines such as weight training, sprint¬ing, and exercises like push-ups, crunches, dips, and leg lifts. Unlike aerobic training, which can be thought of as a body-wide approach to fitness anaerobic activity strengthens and tones specific muscles.

To improve flexibility and posture, reduce the risk of injury, increase physical and mental relaxation, and release muscle tension and soreness, stretching is crucial. One of the most often overlooked and misunderstood aspects of fitness, stretching is often thought of merely as part of a warm-up or cool-down routine. The truth is, stretching is the foundation on which the others can be built. Ideally, every part of the body should be put through a full range of motion in the course of a day, although doing so within the span of a week is certainly acceptable.

It is crucial to flex the muscles in those areas you’ll be working out during any other routine. Different stretches are good for different activities.

Runners should stretch their lower back, the muscles in the back of the thighs and calves, and the inner thighs. A racquetball player should stretch those same leg muscles, as well as the muscles in the upper back, shoulders, and neck.

Whatever your goals, wherever your emphasis, a good fitness plan will include a variety of execises for different parts of the body.

Don’t just work out your upper or lower, front or back imbalance can result in more damage than no workout at all.

A fitness appraisal by a certified exercise physiologist or personal trainer is an excellent way to determine your basic fitness and what will help you most.