Train or Die?
The triathlon challenges athletes to swim, bike and run, in that order, without stopping. It's rising in popularity, with nearly two million participants a year. Yet, between 2006 and 2008, 14 people died in the U.S. while competing. Interestingly, despite the fact that it is the first event, all but one of these deaths happened during the swim portion. When compared to the number of participants, this death rate is almost twice that of marathoners.