A relay race is a racing competition where members of a team take turns completing parts of racecourse or performing a certain action. Relay races take the form of professional races and amateur games. Relay races are common in running, orienteering, swimming, cross-country skiing, biathlon, or ice skating. In the Olympic Games, there are several types of relay races that are part of track and field. Relay race, also called Relay, is a track-and-field sport consisting of a set number of stages (legs), usually four, each leg run by different members of a team. The runner finishing one leg is usually required to pass the next runner a stick-like object known as a "baton" while both are running in a marked exchange zone. In most relays, team members cover equal distances: Olympic events for both men and women are the 400-metre and 1,600-metre relays. Some non-Olympic relays are held at distances of 800 m, 3,200 m, and 6,000 m. In the less frequently run medley relays, however, the athletes cover different distances in a prescribed order—as in a sprint medley of 200, 200, 400, 800 metres or a distance medley of 1,200, 400, 800, 1,600 metres.

Freestyle is a category of swimming competition, defined by the rules of the International Swimming Federation (FINA), in which competitors are subject to only a few limited restrictions on their swimming stroke. Freestyle races are the most common of all swimming competitions, with distances beginning with 50 meters and reaching 1,500 meters, also known as the mile. The term 'freestyle stroke' is sometimes used as a synonym for 'front crawl', as front crawl is the fastest surface swimming stroke. It is now the most common stroke used in freestyle competitions.