It is common knowlege that physical activity is good for your health. Exercising is good for weight maintenance and heart health, and health professionals advocate physical activity in moderation. But how much is too much? There is a growing body of research that has found that excessive endurance exercise may actually be just as bad as being sedentary. A new study at the Minneapolis Heart Institute Foundation looked at long term marathon and ultra-marathon runners and found that plaque buildup in their coronary arteries was 62% higher than those who were sedentary. Don’t take this as an excuse to stay on the couch! Being sedentary is unhealthy; the best long term benenfits appears to come from regular, moderate exercise.