A physically active lifestyle benefits your heart in several ways: It increases your heart's ability to pump blood, promotes weight loss and can help protect against high blood pressure and diabetes. What's more, regular exercise lowers triglyceride levels while increasing levels of "good" HDL cholesterol.
A sedentary lifestyle doesn't exercise the heart — a muscle — so it can lose its strength, flexibility and endurance. A sedentary life is defined as being physically inactive at work and at home and failing to participate in exercise for at least 20 continuous minutes at least three times a week. By gradually increasing the amount of exercise you do, you can improve your cardiovascular and overall fitness level in as little as eight weeks.
Cardiovascular fitness increases the efficiency of oxygen use by your body and its capacity for work. Exercise increases your heart's strength, endurance and efficiency. A fit heart pumps 25 percent more blood per minute when at rest and over 50 percent more blood per minute during physical exertion than an unfit heart. It's therefore less subject to strain when demands on it increase. A fit heart also has a lower resting heart rate — usually 60 to 70 times a minute compared to an unfit person's heart beat rate of 80 to 100 times a minute.
In general, try to set up your program so that you expend about 1,000 to 2,000 calories a week with exercise. Here are some examples of the number of calories burned during some exercises:
Average Number of Calories Burned in 10 Minutes
Caloric expenditure for your weight:
Workouts That Work
|5 mph (12 minutes/mile)
|6 mph (10 minutes/mile)
|2 mph (30 minutes/mile)
|3 mph (20 minutes/mile)
|4 mph (15 minutes/mile)
To increase cardiovascular fitness, you need to do aerobic exercise, which refers to activities that require the continuous, rhythmic contracting of the body's large muscle groups. To supply your muscles with the steady supply of oxygen needed to meet their energy needs during an aerobic workout, the rate and depth of your breathing increases and eventually you'll perspire.
Aerobic exercise should not be so intense that your muscle cells run short of oxygen. (If you find yourself gasping for air during aerobic exercise, slow down until your breathing is steady again.) Oxygen deficiency may occur with activities such as isometric exercises like weight-lifting. These activities increase muscle tone and bulk, but they don't appear to have cardiovascular benefits. A cardiovascular fitness program has three parts: warm-up, conditioning aerobic exercise and cool-down.
- The warm-up phase should include stretching and low-intensity endurance exercises to gradually increase your heart rate, body temperature, and blood flow to your muscles.
Follow this with at least 20 minutes of aerobic workout.
End with 5 to 10 minutes of low-intensity exercises, such as walking on a treadmill or stepping very gently on a stair machine. Follow those low-intensity exercises with some stretching.
Your workout should be intense enough and long enough to achieve a cardiovascular training effect. Try for about 30 minutes a day, at least three times a week on nonconsecutive days. Ideally, if you are trying to lose weight, try to work your way up to 60 to 90 minutes a day, 5 to 7 days per week. If you haven't exercised for a long time, start with 5 minutes or less and gradually work your way up. The intensity of your exercise should be strenuous enough so that you feel you are working, but it need not be exhausting. It's best to get a doctor's approval before starting an exercise program if you are severely overweight; over age 40; have heart or lung disease, diabetes, arthritis or kidney disease; or had parents, brothers or sisters who had evidence of coronary artery disease before age 55. And stop exercising immediately if you experience:
- Chest discomfort or pressure
A severe shortness of breath
A burst of very rapid or slow heart rate
An irregular heart rate
Marked joint or muscle pain
Dizziness or fainting
For most people, the hardest part about a regular exercise program is staying motivated. To help, try these strategies:
Chart your progress
Keeping a workout journal is a great way to see how you're improving. When you first start exercising, you may find you can ride a stationary bicycle for only 10 minutes; gradually this will increase. The record will show how far you've come and will help you set new goals.
Choose an activity that fits your personality
No single form of aerobic exercise is best. Do you like to exercise alone or in groups? If you prefer solitude, walking may be your first choice. If group activities appeal to you, enroll in an aerobic dance or water aerobics class. Do you like being outside or would you prefer to stay indoors?
Watch television or listen to music while you use indoor exercise equipment.