Yes! Various studies have shown that physical inactivity is a risk factor for heart disease. Overall, the results show heart disease is almost twice as likely to develop in inactive people than in those who are more active. Regular physical activity (even mild to moderate exercise) can help reduce your risk of heart disease. In fact, burning calories through physical activity may help you lose weight or stay at your desirable weight - which also helps lower your risk of heart disease. The best exercises to strengthen your heart and lungs are the aerobic ones like brisk walking, jogging, cycling and swimming.

Coronary artery disease is the major cause of heart disease and heart attack in America. It develops when fatty deposits build up on the inner walls of the blood vessels feeding the heart (coronary arteries). Eventually one or more of the major coronary arteries may become blocked - either by the buildup of deposits or by a blood clot forming in the artery's narrowed passageway. The result is a heart attack.

We know that there are several factors that can increase your risk for developing coronary artery disease - and thus the chances for a heart attack. Fortunately, many of these risk factors can be reduced or eliminated.

The risk factors for heart disease that you can do something about are:

Cigarette Smoking, High Blood Pressure, High Blood Cholesterol, Physical Inactivity and Obesity. The more risk factors you have, the greater your risk for heart disease and heart attack.

Cigarette Smoking. Heavy smokers are two to four times more likely to have a heart attack than nonsmokers. The heart attack death rate among all smokers is 70 percent greater than among nonsmokers. People who are active regularly are more likely to cut down or stop cigarette smoking.

High Blood Pressure. The higher your blood pressure, the greater your risk of developing heart disease or stroke. A blood pressure of 140/90 mmHg (millimeters of mercury) or greater is generally classified as high blood pressure. Regular physical activity, even of moderate intensity, can help reduce high blood pressure in some people. This type of activity may also help prevent high blood pressure.

High Blood Cholesterol. A blood cholesterol level of 240 mg/dl (milligrams per decaliter) or above is high and increases your risk of heart disease. A total blood cholesterol of under 200 mg/dl is desirable and usually puts you at a lower risk of heart disease.

Cholesterol in the blood is transported by different types of particles. One of these particles is a protein called high density lipoprotein or HIDL. HIDL has been called "good" cholesterol because research has shown that high levels of HIDL are linked with a lower risk of coronary artery disease. Regular moderate-to-vigorous physical activity is linked with increased HIDL levels.

Physical Inactivity. The lack of physical activity increases your risk for developing heart disease. Even persons who have had a heart attack can increase their chances of survival if they change their habits to include regular physical activity. It can help control blood lipids, diabetes and obesity as well as help to lower blood pressure. Also, physical activity of the right intensity, frequency and duration can increase the fitness of your heart and lungs - which may help protect you against heart disease even it you have other risk factors.

Obesity. Excess weight may increase your risk of developing high blood pressure, high blood cholesterol and diabetes. Regular physical activity can help you maintain your desirable body weight. People at their desirable weight are less likely to develop diabetes. And, exercise may also decrease a diabetic person's need for insulin.

Remember that even if you are active, you should not ignore other risk factors. Reduce or eliminate any risk factors you can to lower your chances of having a heart attack.

Are there any risks in exercising?

Muscles and joints

The most common risk in exercising is injury to the muscles and joints. This usually happens from exercising too hard or for too long - particularly if a person has been inactive for some time. However, most of these injuries can be prevented or easily treated as explained in "Effective ways to avoid injuries".

Heat exhaustion and heat stroke

If precautions are not taken during hot, humid days, heat exhaustion or heat stroke can occur - although they are fairly rare. Heat stroke is the more serious of the two. Their symptoms are similar:

The last two symptoms of heat stroke are important to know. If the body temperature becomes dangerously high, it can be a serious problem.

Both heat exhaustion and heat stroke can be avoided if you drink enough liquids to replace those lost during exercise. And be sure to take the other important precautions listed on page 7 in the section on avoiding injuries.

Heart problems

In some cases, people have died while exercising. Most of these deaths are caused by overexertion in people who already had heart conditions. In people under age 30, these heart conditions are usually congenital heart defects (heart defects present at birth). In people over age 40, the heart condition is usually coronary artery disease (the buildup of deposits of fats in the heart's blood vessels). Many of these deaths have been preceded by warning signs such as chest pain, lightheartedness, fainting and extreme breathlessness. These are symptoms that should not be ignored and should be brought to the attention of a doctor immediately.

Some of the deaths that occur during exercise are not caused by the physical effort itself. Death can occur at any time and during any kind of activity - eating, sleeping, sifting. This does not necessarily mean that a particular activity caused the death - only that the two events happened at the same time.

No research studies have shown that physically active people are more likely to have sudden, fatal heart attacks than inactive people. In fact, a number of studies have shown a reduced risk of sudden death for people who are physically active.

Exercising too hard is not beneficial for anyone, however, and is especially strenuous for out-of-shape, middle-aged and older persons. It is very important for these people to follow a gradual and sound exercise program.

If you consider the time your body may have been out of shape, it is only natural that it will take time to get it back into good condition. A gradual approach will help you maximize your benefits and minimize your risks.