triatlon

Triatlon, or triatlón in several languages, is a multi-sport endurance competition in which athletes complete swimming, cycling, and running in that order, with brief transitions between disciplines. The event tests endurance, versatility, and transitions, as athletes must rapidly switch gear and pacing between each segment.

Distances and formats vary by race. Common formats include sprint (short distances, such as roughly 750 m swim, 20 km bike, 5 km run) and Olympic or standard distances (about 1.5 km swim, 40 km bike, 10 km run). Longer formats exist, notably the half-iron or Ironman 70.3 (about 1.9 km swim, 90 km bike, 21.1 km run) and the full Ironman (3.8 km swim, 180 km bike, 42.2 km run). Some events are draft-legal, allowing riders to ride in pelotons on the bike, while others, particularly long-distance races, enforce non-drafting rules.

History and governance are marked by growth from hobbyist beginnings to a global sport. Modern triathlon arose in the 1960s–1970s in the United States and Europe, with the first modern events around the 1970s. The sport is governed worldwide by World Triathlon (formerly the International Triathlon Union), which oversees elite competitions, standardized rules, and age-group racing. Triathlon became an Olympic sport in 2000, and Olympic-distance races remain among the most prominent formats. In addition to World Triathlon events, the sport features numerous national federations, regional championships, and specialized races such as the Ironman series.

Equipment and safety considerations include a wetsuit allowed in certain water temperatures, swimming goggles, a bike and helmet, running shoes, and optimized transition areas. Training emphasizes aerobic capacity, technique across three disciplines, nutrition, and race strategy.