🏊水泳のルール

Competitive swimming is a timed sport in which each swimmer covers a set distance in a pool as fast as possible. There are four strokes: freestyle (front crawl), backstroke, breaststroke and butterfly. Events are contested individually or as relays.

Cover the required distance in the prescribed stroke in the fastest possible time. The first to touch the finishing wall (or the best time) wins.

• •Four strokes: freestyle (usually front crawl), backstroke, breaststroke, butterfly; each event prescribes one stroke.
• •The start is on a signal, diving from the block (or from in the water for backstroke); a single false start means disqualification.
• •At each turn and at the finish, the swimmer must touch the wall; how depends on the stroke.
• •Each swimmer stays in their own lane and must not obstruct an opponent.
• •After a start or turn, underwater swimming is allowed for at most 15 metres in freestyle, backstroke and butterfly before the head must break the surface; in breaststroke the underwater phase is limited to one arm pull plus one dolphin kick.
• •In the individual medley the order is fixed: butterfly, backstroke, breaststroke, freestyle.

Swimming is not scored in points but by the clock: each swimmer's time is measured, usually to the hundredth of a second via the electronic touch-pad. Ranking runs from the shortest time to the longest. In relays it is the team's combined time that counts.

An event is a single race over a set distance (e.g. 50 m, 100 m, 200 m, 400 m, 800 m, 1500 m). Major competitions are organised into heats, then semi-finals and finals depending on the number of entrants. The format (long or short course) affects the number of turns.

The winner is the swimmer (or relay) with the best time while complying with the rules of their stroke. Any technical infringement can lead to disqualification, which voids the result.