Exercise has many benefits. Our bodies thrive on regular physical activity. Exercise provides both physical and emotional rewards. Exercise can:
These physical effects decrease the risk of stroke, heart disease, and diabetes. Exercise can also help you lose weight or keep a healthy weight.
Among the emotional benefits of exercise are:
Exercise affects our brain chemistry. For example, exercise can help treat mild depression. It can also help you have more energy.
Finally, exercise increases the body's metabolic rate. Regular exercise raises the number of calories your body uses during activity and for several hours afterward.
Aerobic exercise, which involves continuous activity, increases endurance and helps your body use oxygen more effectively. Your lungs work harder to bring in more oxygen and your heart pumps harder to send blood to the muscles. This process strengthens your lungs, heart, bones, and muscles. Aerobic activities that increase cardiovascular fitness include:
Other types of exercise, such as weight lifting and stretching, can improve muscle strength and flexibility. Such exercise improves endurance, dexterity, and balance.
Exercises performed at low and moderate intensity will help you stay fit and healthy. You do not need to exercise strenuously to improve your health. For example, regular, moderate activity, such as three 10-minute walks a day, reduces your risk of death from heart disease by as much as 60%.
With your healthcare provider's approval, your goal should be 30 to 90 minutes of moderate exercise a day, most days of the week. Moderate aerobic exercise is generally defined as requiring the energy it takes to walk 2 miles in 30 minutes. You may need to exercise 60 minutes a day to prevent weight gain and 90 minutes a day to lose weight. Be sure to check with your healthcare provider before starting your exercise program.
Before beginning an exercise program, consider the following questions:
The following table can help you plan your exercise program. It lists the average number of calories burned per hour in some common physical activities. Some of the activities can be either moderate or vigorous, depending on how fast you do them (for example, walking or bicycling).
Moderate Physical Activity Calories/hr for a 154-lb Person* ----------------------------------------------------------- Hiking 370 Light gardening/yardwork 330 Dancing 330 Golf (walking and carrying clubs) 330 Bicycling (less than 10 miles per hour) 290 Walking (3.5 miles per hour) 280 Weight lifting (general light workout) 220 Stretching 180 Vigorous Physical Activity Calories/hr for a 154-lb Person* ------------------------------------------------------------ Running/jogging (5 miles per hour) 590 Bicycling (more than 10 miles per hour) 590 Swimming (slow freestyle laps) 510 Aerobics 480 Walking (4.5 miles per hour) 460 Heavy yard work (chopping wood) 440 Weight lifting (vigorous effort) 440 Basketball (vigorous) 440 ------------------------------------------------------------ * Calories burned per hour will be higher if you weigh more than 154 pounds (70 kilograms) and lower if you weigh less. Source: Adapted from the Dietary Guidelines for Americans 2005.
You should include warm-up and cool-down exercises before and after aerobic exercise. Muscles and joints that have not been used are cool. Start out walking slowly and then gradually increase the pace over a 5-minute period. If you cannot walk, try easy cycling or other activities at slow, easy paces. This gives the body time to increase blood flow to the working muscles and joints and prepare them for harder work. Then stretch your muscles and bend your joints for 5 to 10 minutes. This warms your muscles and joints by increasing the flow of blood to them. It makes them more flexible and less prone to injury. Your choice of stretches depends on the type of exercise you plan to do. Hold each stretch for 30 seconds and do not bounce.
Right after exercise, allow your heart rate to return slowly to normal. For example, walking slowly for about 5 minutes will let you cool down and allow your heart and breathing to return to normal levels. Then stretch the muscles used during your exercise. After stretching, your muscles will be more flexible and less stiff. Devote a total of 5 to 10 minutes to cooling down. You can use warm-up exercises for cool-down exercises.