A heart attack is caused by a sudden and complete obstruction of the blood flow to a part of the heart muscle usually caused by plaque breaking off blocking the flow of blood. Studies show endurance athletes may have more plaque than non-exercises but are less likely to suffer a heart attack. What does that mean in terms of exercise and heart disease? Watch this video now to find out. Click the Red More Button in your email or the image below if you are on our website.