The aquatic sport of swimming is based on the human act of swimming, that is, locomotion in water by self propulsion, usually with the goal to complete a given distance in the smallest time. There are also swimming competitions based on endurance or precedence rather than speed, such as crossing the English Channel or some other stretch of open water. As a sport, swimming is usually distinguished from other acquatic sports (such as diving, synchronized swimming and water polo) that involve the act of swimming but where the goal is neither speed nor endurance.

Swimming has been part of the modern Olympic Games since their inception in 1896, and is governed by the Fédération Internationale de Natation (FINA). The belief is widely held that swimming is the best aerobic exercise in the world.

Training for the Triathlon Swim: