The Muscular System - Taking care: keeping the muscular system healthy
As humans age, all muscle tissues decrease in size and power. Muscle fibers die and are replaced by fibrous connective tissue or by fatty tissue. The connective tissue makes the muscles less flexible. Movement is limited. Even muscles with normal tone will atrophy or waste away.
The effects of this eventual decline in the muscular system can be offset by regular exercise throughout an individual's life. Exercise helps control body weight, strengthens bones, tones and builds muscles, and generally improves the quality of life for people of all ages.
Some types of exercise help to strengthen the heart and lungs. These activities are called aerobic exercises. The American College of Sports Medicine and the Centers for Disease Control and Prevention recommend that people engage in moderate to intense aerobic activity four or more times per week for at least thirty minutes at a time. Walking, jogging, cycling, swimming, and climbing stairs are just a few examples of aerobic activity. These exercises also force the large muscles of the body to use oxygen more efficiently, as well as store greater amounts of ATP.
Exercises that increase the size and strength of muscles are called anaerobic exercises. These types of exercises require quick bursts of energy. Weight lifting (also known as strength training) and sprinting are just two examples anaerobic activity. As muscles grow larger, they require more energy to work, even when the body is at rest. To meet this increased need, the body is forced to use its stored nutrients more efficiently.
When combined with exercise, the following help keep the muscular system operating at peak efficiency: proper nutrition, healthy amounts of good-quality drinking water, adequate rest, and stress reduction.
The "Food Guide" Pyramid developed by the U.S. Departments of Agriculture and Health and Human Services provides easy-to-follow guidelines for a healthy diet. In general, foods that are low in fat (especially saturated fat), low in cholesterol, and high in fiber should be eaten. Fat should make up no more than 30 percent of a person's total daily calorie intake. Breads, cereals, pastas, fruits, and vegetables should form the bulk of a person's diet; meat, fish, nuts, and cheese and other dairy products should make up a lesser portion.
Stress taxes all body systems. Any condition that threatens the body's homeostasis or steady state is a form of stress. Conditions that cause stress may be physical, emotional, or environmental. When stress lasts longer than a few hours, higher energy demands are placed on the body. Combining exercise with proper amounts of sleep, relaxation techniques, and positive thinking will help reduce stress and keep the body in balance.