This is your heart for endurance sports

We've all read the stories about the man who dropped dead running his first marathon or the athlete who nearly crossed the finish line of his triathlon – but instead had a heart attack. Sounds alarming, but the number of deaths in endurance sports is still relatively low, according to new research by the American Heart Association.

"The 50-year-old former college athlete with known or hidden heart disease who has been sedentary for years opting for a triathlon is at greatest risk," said lead study author Barry A. Franklin, Ph.D. A few more facts: Almost half of the people who have a heart attack during a triathlon are beginners. Men are four to six times more likely to have a heart attack (and die from it) than women during an endurance event, possibly because they are older, on average, and run faster and put more strain on their heart, Franklin suggests. And half of all exercise-related cardiac events occur during the last mile of the marathon.

"It's a great temptation to think," I'm almost done, let me sprint as hard as possible and beat my best time, "he notes. This sharp increase in heart rate and blood pressure increases the likelihood of a heart attack, either because of the heart does not get adequate blood flow or plaque may tear in the arteries.

Franklin's advice: train progressively and don't sprint to the finish line.

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