A triathlon is a multiple-stage competition involving the completion of three continuous and sequential endurance disciplines.While many variations of the sport exist, triathlon, in its most popular form, involves swimming, cycling, and running in immediate succession over various distances. Triathletes compete for fastest overall course completion time, including timed "transitions" between the individual swim, cycle, and run components.The word "triathlon" is of Greek origin and comes from the words treis (three) and athlos (contest).
Triathlon races vary in distance. According to the International Triathlon Union, and USA Triathlon, the main international race distances are:
Transition is the process of moving from one triathlon discipline to the next, for example, Swim to Bike or Bike to Run. The transition from swim to bike is known as T1 and the transition from bike to swim is T2.
A transition area will be set up by the race organisers where competitors are required to rack bikes and layout kit before the race starts. Competitors will typically change shoes, put on cycle helmets etc. in the transition area in preparation for the next leg.