While taekwondo and triathlon both debuted as the newest Olympic sports at the Sydney 2000 Games, triathlon was literally the newest sport. Although the origins of taekwondo date back thousands of years, the triathlon dates back to 1978.
The ultimate endurance test, it requires athletes to excel at three very different pursuits - swimming, cycling and running. The sport demands particularly intense discipline because each area requires a high-level training schedule.