Many people think that exercising is important when it comes to protecting your heart. They are right. However, exercise is not a magical cure for heart disease. People who exercise can still have heart disease. Unfortunately, this is a fact that many patients like to cite whenever they try to justify their unwillingness to comply to prescribed exercise.
Marathon runners can suffer from a heart attack, but that does not mean that exercise is useless. In fact, those unfortunate marathon runners would most likely have had their heart attacks much sooner if they were not exercising regularly. Regular exercise also results in improving your cardiac reserve, meaning if you survive a heart attack your heart will continue to function more effectively than it would if had you not been exercising regularly.
One reason active people still suffer from heart disease is that family and personal history still have a major role in heart health. If you come from a family where your parents and grand parents have all had heart attacks by the time they were 50, you are automatically at an increased risk for heart disease...even if you exercise every day. Again, exercise is still beneficial to your cardiovascular system, but it will not necessarily stop you from ever getting the heart attack that your genetics has preordained for you. Personal history is important too because if you have been significantly overweight from the time you were 5 until you were 35, you are still at risk for heart disease even if you suddenly train your way up to running marathons. Those 30 years of unhealthy living may have resulted in atherosclerotic plaques forming in your blood vessels that can rupture to cause a heart attack in your future and, unfortunately, they do not just suddenly disappear if you decide to become more active.
Heart disease is complex and there are many different factors that can put you at risk for a cardiovascular event. The point I am trying to make here is that exercising within reasonable limits will almost always decrease your risk for a cardiac event; however, exercising cannot guarantee that your heart will not fail you. So please, do not decide to ignore your doctor's request for you to be more active because you read about a man who had a heart attack while going for a jog. Instead, just mention your concerns and keep asking questions until your physician gives you an explanation that satisfies you.