Did you know that triathletes are prone to dying suddenly?

What caused the deaths?

Triathlon participants do not drop dead all the time. It's rare. From 2006 to 2008 only fourteen triathletes died while competing, out of something like 900,000 total participants.

But that's still twice as many deaths during competition as compared to marathons, for example.

A study found that of the fourteen triathletes who died, four had underlying heart problems.

What about the other ten?

Interestingly, all but one died during the swimming part.

One gave out while biking and apparently no triathletes have died while running.

Different in temperature

It may have anything to do with the temperature difference when you jump into cold water. Many triathletes wear some kind of wet suit, but still, diving into a cold lake or ocean whisks a lot of heat away from the body, which could trigger a heart attack.

The study also suggested that if you're having trouble in the water it's simply harder to call for help than it would be on a bike or while running.