No swimmer may swim more than one leg of the relay, which is swum in backstroke, breaststroke, butterfly and freestyle order. The medley relay is 400 metres -or four by 100 metres. Many races are won or lost in starts and turns. In the start, the swimmer is called to the starting position by the starter who visually checks that all swimmers are still. Then, once the starter is satisfied, the race is started by either a gun or electronic tone.
Quick turns are essential to a good race.
In all events the swimmer must touch the wall, but in the freestyle and backstroke the swimmer may somersault as he or she reaches the wall, touching only with the feet. In the other two competitive strokes, the swimmer must touch the wall with both hands before executing the turn. The slightest mistake can cost precious hundredths of seconds -and the race. The 200 metre events require the swimmer to have a sense of pace as well as the ability to swim in a controlled speed. Swimming the first portion of the race at too fast of a pace can sap a swimmers strength and cause a poor finish.