Competitive swimming looks simple from the stands, but each of the four recognized strokes comes with its own set of technical rules governing body position, arm movement, kicking, and how swimmers must touch the wall. This article breaks down freestyle, backstroke, breaststroke, and butterfly, along with the starting and turning rules that officials enforce at every level of competition.
Freestyle: The Open-Ended Stroke
Freestyle is unique among the four strokes because the rules do not actually dictate a specific swimming motion. Under rules set out by World Aquatics, a freestyle event simply requires that a swimmer covers the distance using any style, provided it is consistent with general competition rules around sportsmanship. In practice, nearly every swimmer uses the front crawl, which involves alternating overhead arm strokes and a flutter kick, because it is the fastest technique available.
Because freestyle is open, it is also the stroke used in the "freestyle" leg of an individual medley or medley relay, where swimmers typically choose front crawl by convention rather than requirement. The main technical restrictions in freestyle involve touching the wall at the finish, which can be done with any part of the body, unlike the other three strokes.
Backstroke: Racing on Your Back
Backstroke is swum, as the name suggests, on the back, and officials watch closely to confirm swimmers stay in a generally supine position throughout the race, apart from the moments immediately before a turn. The stroke features alternating arm movements with a continuous flutter kick.
A swimmer is permitted to rotate past vertical toward the breast immediately before executing a turn, as this rotation is a necessary part of modern turn technique, but swimmers cannot simply roll onto their front and swim additional strokes in that position. At the finish, the swimmer must touch the wall while still on the back.
Breaststroke: The Most Regulated Stroke
Breaststroke carries the most detailed technical restrictions of any competitive stroke, largely because its symmetrical, simultaneous movements are easy for officials to judge against a precise standard.
- Both arms must move simultaneously and symmetrically, with no alternating movement.
- Both legs must also kick simultaneously and symmetrically; the kick is a distinctive whip-like or circular motion rather than the flutter kick used in other strokes.
- After the start and after each turn, a swimmer is allowed one arm stroke pulled back to the legs, during which a single downward dolphin kick is permitted, before beginning the breaststroke kick.
- Some part of the swimmer's head must break the surface of the water during each complete stroke cycle, except during the single pull-out stroke following the start and turns.
- At the finish and at every turn, the swimmer must touch the wall with both hands simultaneously, at or near the same level, with shoulders roughly in line with the water surface.
Because breaststroke technique is judged so precisely, it tends to generate more disqualifications for technical violations than the other strokes, particularly around illegal kicks (adding a flutter or scissor kick) or uneven hand touches at the wall.
Butterfly: Symmetry in Motion
Butterfly also requires simultaneous, symmetrical movement of both arms and both legs, but unlike breaststroke, the arms recover over the water rather than underneath it, and the legs use a dolphin kick, where both legs move together in an undulating, up-and-down motion rather than the breaststroke's whip kick.
Scissor or alternating flutter kicks are not permitted in butterfly. As with breaststroke, both hands must touch the wall simultaneously at turns and at the finish of the race.
Starting Rules: Platform Starts vs. Backstroke Starts
How a race begins depends on which stroke is being swum first.
- Dive starts: For freestyle, breaststroke, butterfly, and individual medley events, swimmers begin on the starting platform (the starting block) and dive forward into the water at the starting signal.
- Backstroke and medley relay starts: When backstroke is the first stroke swum, swimmers start in the water. They grip the starting block or wall with their hands, typically place their feet against the wall below the waterline, and push off backward at the signal rather than diving forward from a standing position.
In all starts, swimmers must remain stationary once they have taken their mark, and a false start, where a swimmer moves before the starting signal, can result in disqualification under current rules.
Turn Rules by Stroke
Turns are judged according to the stroke being swum at that point in the race, which matters most in individual medley events where the stroke changes partway through.
- Freestyle turns: Often executed as a "flip turn" or "tumble turn," where the swimmer somersaults underwater and pushes off the wall with the feet. Any part of the body may touch the wall, since freestyle has no hand-touch requirement.
- Backstroke turns: Swimmers may rotate onto the front during the approach to the wall as part of executing the turn, then perform a flip-style turn, pushing off still rotating back toward the supine position.
- Breaststroke and butterfly turns: These require a simultaneous two-hand touch on the wall before the swimmer may turn, reflecting the same symmetry rules that apply during the stroke itself. This is typically an "open turn," where the swimmer's head stays above water, the body rotates, and the swimmer pushes off on the side or front rather than flipping underwater.
After any turn, rules generally limit how far a swimmer may travel underwater before resurfacing, and specify that some part of the head must break the surface by a defined distance marker, with breaststroke carrying its own specific pull-out allowance as described above.
Why These Rules Exist
At first glance, rules about hand touches and kick symmetry can seem overly technical, but they exist to preserve the distinct identity of each stroke. Without them, breaststroke and butterfly could blur into faster hybrid techniques, undermining the point of having four separate events. Officials, known as stroke judges and turn judges, are positioned along the pool deck specifically to watch for these technical details during competition.
Quick Recap
- Freestyle has no required technique; front crawl is simply the fastest style swimmers choose to use.
- Backstroke is swum on the back, with limited rotation allowed only immediately before a turn.
- Breaststroke requires simultaneous symmetrical arm and leg movement, a single pull-out stroke after starts and turns, and a two-hand touch at the wall.
- Butterfly requires simultaneous arm recovery over the water and a two-legged dolphin kick, with no scissor kicking allowed.
- Dive starts are used for freestyle, breaststroke, butterfly, and most medley events, while backstroke events start in the water.
- Turn requirements, especially the two-hand touch, differ by stroke and are strictly enforced by stroke and turn judges.