Section 1. Fundamentals

Chapter 6. Exercise and Fitness

Topics: Introduction | Benefits of Exercise | Starting an Exercise Program | Preventing Injury | Choosing the Right Exercise

Choosing the Right Exercise

There are many forms of exercise, and each type of exercise has its advantages and disadvantages. For example, walking is relatively easy on the joints; during walking, at least one foot is on the ground at all times, so the force with which the foot strikes the ground is never much more than the person's weight. However, walking burns fewer calories than does running. Swimming rarely results in muscle tears, because the muscles are supported by the water. However, because swimming is not a weight-bearing exercise, it does not help prevent osteoporosis. Bicycles are pedaled in a smooth circular motion that does not jolt the muscles, but bicycling requires balance, and it is not always possible to enjoy this sport free of traffic and the dangers of cars.

Other choices regarding exercise exist as well. Some people prefer to exercise in a gym or at home, whereas others prefer to exercise outdoors. Some people have a very structured exercise routine, whereas others simply incorporate exercise into their lifestyle, for example, by walking rather than driving. Choosing the right exercise is a matter of finding an activity that is fun, safe, and sustainable.

Walking is a well-balanced form of exercise for most people, regardless of age. Many older people are able to keep fit through regular walking programs. However, walking slowly will not make a person very fit. To walk faster, a person can take longer steps in addition to moving the legs faster. Steps can be lengthened by swiveling the hips from side to side so that the feet can reach further forward. Swiveling the hips tends to make the toes point outward when the feet touch the ground, so the toes do not reach as far forward as they would if they were pointed straight ahead. Therefore, a walker should always try to point the toes straight ahead. Moving the arms faster helps the feet move faster. To move the arms faster, a person bends the elbows to shorten the swing and reduce the time the arms take to swing back and forth from the shoulder. People with instability or severe joint injury may find walking difficult.

Swimming exercises the whole body--the legs, arms, and back--without stressing the joints and muscles. Often, swimming is recommended for people who have muscle and joint problems. Swimmers, moving at their own pace and using any stroke, can gradually work up to 30 minutes of continuous swimming. If weight loss is one of the main goals of exercise, however, swimming is not the best choice. Exercise out of water is more effective because air insulates the body, increasing body temperature and metabolism for up to 18 hours. This process burns extra calories after exercise as well as during exercise. In contrast, water conducts heat away from the body, so that body temperature does not rise and metabolism does not remain increased after swimming.

Riding a bicycle is good exercise for cardiovascular fitness. Pedaling a bicycle strengthens the upper leg muscles. With a stationary bicycle, the tension on the bicycle wheel should be set so that the rider can pedal at a cadence of 60 rotations per minute. As they progress, riders can gradually increase the tension and the cadence up to 90 rotations per minute. A regular bicycle adds the challenges and joys of balance and coping with changes in terrain but adds the dangers of dealing with traffic. However, some people cannot maintain their balance, even on a stationary bicycle, and others will not use one because the pressure of the narrow seat against the pelvis feels uncomfortable.

A recumbent stationary bicycle is both secure and comfortable. It has a contoured chair that even a person who has had a stroke can sit in. Also, if one leg is paralyzed, toe clips can hold both feet in place, so that the person can pedal with one leg. A recumbent stationary bicycle is a particularly good choice for older people, many of whom have weak upper leg muscles. As a result of having weak upper leg muscles, many older people have difficulty rising from a squatting position, getting up from a chair without using their hands, or walking up stairs without holding on to the railing.

Aerobic dancing, a popular type of exercise offered in many communities, exercises the whole body. People can exercise at their own pace with guidance from experienced instructors. Lively music and familiar routines make the workout fun, and committing to a schedule and exercising with friends can improve motivation. Aerobic dancing also can be done at home with videotapes. Low-impact aerobic dancing eliminates the jumping and pounding of regular aerobic dancing, thus decreasing stress on the knee and hip joints. However, the benefits of aerobic dancing, especially in terms of weight loss, are proportional to the intensity.

Step aerobics stresses primarily the muscles in the front and back of the upper legs (the quadriceps and hamstrings) as a person steps up and down on a raised platform (a step) in a routine set to music at a designated pace. As soon as these muscles start to feel sore, exercisers should stop, do something else, and return to step aerobics a couple of days later.

Water aerobics is an excellent choice for older people and for those with weak muscles because it prevents falls on a hard surface and provides support for the body. It is often used for people with arthritis. Water aerobics involves doing various types of muscle movements or simply walking in waist- to shoulder-deep water.

Cross-country skiing exercises the upper body and the legs. Many people enjoy using machines that simulate cross-country skiing, but others find the motions difficult to master. Because using these machines requires more coordination than most types of exercise, a person should try out a machine before buying one. Cross-country skiing outdoors is more enjoyable to some people but adds the challenges of exercising in the cold.

Rowing strengthens the large muscles of the legs, shoulders, and back and helps protect a healthy back from injury. More people use rowing machines than row on water, although rowing outdoors adds the challenge of coordinating the oars and the joys of spending time in a boat. However, a person who has back problems should not row without a doctor's approval.

Resistance training is an anaerobic exercise meant to build strength and muscle mass. It is far more effective than other forms of exercise for achieving these goals but is less effective than aerobic exercise for burning calories (and thus losing weight) or improving cardiovascular performance at similar intensity. However, increased muscle mass may eventually help maintain a lean body weight, because muscle uses more calories than fat. The aerobic component of resistance training can be increased by increasing the repetitions performed at each station and by decreasing the time for rest between each set.

Weight lifting carries a higher risk of injury to muscles and joints if exercises are not done properly. Most people who intend to lift weights benefit from initial supervision that includes instruction on how to set the weights and seat levels and how to breathe during repetitions (out as one pushes or pulls; in during relaxation). For most people, weights should be set so 10 to 15 repetitions of each exercise can be performed. Weights that are too heavy increase the risk of injury. The part of the body trained should be varied so that a particular body part is not exercised more than every few days.

See the table Calories Burned During Exercise.