The benefit of exercise in the treatment and prevention of heart disease should not be underestimated. Physical inactivity is known to increase the risk of heart disease. Physical activity combats this risk by:
1. Reducing blood cholesterol, triglycerides and low density lipoproteins (LDL) while increasing high density lipoproteins (HDL).
2. Reducing blood pressure and resting heart rate which decreases the workload on the heart.
3. Alleviating stress and anxiety.
4. Assisting with weight loss.
For the average adult, fitness is the ability to: (1) perform daily activities without undue fatigue; and (2) be able to respond to sudden physical and emotional stress without overtaxing the heart. Fitness relies upon a healthy heart to deliver oxygen to the body, thereby supplying endurance and stamina.
There are two basic types of exercise: isotonic and isometric. Isometric exercise is a sustained contraction of large muscles, such as weight lifting, and puts a disproportional workload on the heart and limits the amount of oxygen delivered to the heart. Isotonic or aerobic exercise, on the other hand, is accomplished by alternate contraction and relaxation of large muscles. This form of exercise promotes cardiovascular fitness by strengthening the heart muscle. Excellent examples of this form of exercise are walking, biking, cross-country skiing, and swimming. The effects of conditioning last only as long as you continue to exercise, therefore it must be included as a lifetime process for the results to be lasting.
Aerobic exercise is the type recommended to strengthen the heart and cardiovascular system. Studies show that exercising aerobically 3-4 times a week for at least 30 minutes is enough to accomplish this.
Please remember that if you have suffered a recent cardiac event you must discuss your exercise program with your cardiologist. The intensity and frequency of your aerobic exercise will probably need to be modified to insure safety. In general, a low level exercise program during recovery would consist of walking several times a day. You may gradually increase the pace and distance of your walks and include some inclines as you recover and your stamina increases.
As with all exercising, your program should include a warm-up and cool down period. The warm-up and cool down are important because they prepare the body for a change of activity level by slowly altering body temperature, blood pressure, heart rate, and respiration. The warm-up and cool-down are a minimum of five minutes in duration and consist of slow walking.
ENVIRONMENTAL CONSIDERATIONS
1. Exercising in hot weather: Heat and humidity decrease exercise tolerance by adding an extra demand on the heart to cool the body. Therefore, it is best to exercise in the coolest times of the day, early morning or evening. If the temperature is above 80-85 degrees F and/or the humidity is high, consider exercising in an environmentally controlled area such as a mall or using a stationary bike in an air-conditioned room. Be sure to wear loose, light weight clothing to aid in the elimination of body heat. Drink plenty of water before and after exercise in order to replace fluid lost through respiration and perspiration.
2. Exercising in cold weather: Be sure to exercise in the warmest part of the day, layering your clothing to control heat loss. Forty percent of body heat is lost through the head, therefore a hat is indicated. Wearing a scarf across the nose and mouth is helpful as it warms the air momentarily before it is inhaled into the lungs. If the weather is inclement or the temperature is cold (below 32 degrees F), consider exercising indoors in an environmentally controlled area.
3. Air pollution: The carbon dioxide released from cars replaces the oxygen taken into the lungs. Therefore, avoid heavily traveled roads, especially during rush hour. Utilize side roads or bike/walking paths in your local park.
SIGNS AND SYMPTOMS OF EXERCISE INTOLERANCE
It is normal to feel pleasantly tired when first beginning an exercise program. Mild muscle fatigue or soreness may occur due to unaccustomed exercise. These minor complaints should go away as you progress through the program.
If you should experience excessive shortness of breath, muscle cramps, pain, or extreme fatigue, follow the steps below to modify your program:
1. Stop and rest until these symptoms subside.
2. Return home at slower pace and take a short-cut.
3. Over the next several days, walk more slowly or for a shorter distance, then gradually increase your distance and pace.
If you experience chest pain while walking follow these steps:
1. Stop your activity and sit down. Rest will often relieve chest pain. To return home, take a short cut, walking at a slower pace.
2. Unrelieved chest pain after rest requires nitroglycerine if prescribed by your physician. If you continue to have chest pain unrelieved by rest, you must call your cardiologist immediately and get to an emergency room promptly.
REMEMBER: ALWAYS CHECK WITH YOUR PHYSICIAN BEFORE STARTING AN EXERCISE PROGRAM.