The men and women in triathlons are called triathletes.
Triathletes must work hard all year to get ready.
Evert day, they run an swim and ride their bicycles.
They must also do special exercises for the bodies.
After many months of work, they are ready for a race.
There are many races in many countries.
One famous triathlon is the lronman race in Hawaii.
Another is the Noosa race in Australia.
Triathletes come to these races all over the world.