Backstroke
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Backstroke is one of the three swimming styles regulated by FINA, and the only regulated style swum on the back. This has the advantage of easy breathing, but the disadvantage of not seeing where the swimmer is heading to. It is also the only competition swimming style that starts in the water. The swimming style is similar to an upside down front crawl. Both backstroke and front crawl are long-axis strokes.
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Speed and Ergonomics
Backstroke is the second slowest speed after breaststroke. Due to the alternating arm stroke, there is always one arm engaged and the overall swimming speed does not vary very much throughout the cycle. The max. swimming speed is around 1.84 meter per second. Due to its position on the back, backstroke uses different muscles in the upper body than other styles.
History
Backstroke was the first regulated style other than Freestyle which was swum at competitions. The 1900 Summer Olympics in Paris included a 200m backstroke race. In the early times, backstroke was swum with straight arms, but in the modern times, it is almost always swum with bent arms underwater. (see: History of swimming)
Technique
In the initial position, the swimmer lies flat on his back, arms stretched forward, and legs extended backwards.
The Arm Movement
In backstroke, the arms contribute most of the forward movement. The arm stroke consists of three parts, the pull phase, the push phase, and the recovery. The arms alternate that always one arm is underwater (pulling or pushing) while the other arm is recovering. One complete arm turn is considered one cycle. From the initial position, one arm sinks slightly under water and turns the palm outward in preparation for the pull phase. For the remaining pull and push phase, the hand stays in the same horizontal plane 10-20cm below the water surface.
During the pull phase the hand follows a semi circular path from the initial position to the side of the hip. The palm is always facing away from the swimming direction, and the elbow always points downward towards the bottom. This is done so that both the arms and the elbow can push the maximum amount of water back in order to push the body forward. At the height of the shoulders the upper and lower arms should have its maximum angle of about 90 degrees.
The push phase consists of pushing the palm of the hand as far down as possible with the fingers pointing upward. Again, the goal is to push the body forward against the water. At the very end of the push phase, the palm flaps down for a last push forward down to a depth of 45cm, also known as the Buggy Whip. Besides pushing the body forward this also helps with the rolling back to the other side as part of the body movement. During the pull and push phase, the fingers of the hand can be slightly apart, as this will increase the resistance of the hand in the water due to turbulence.
To prepare for the recovery phase, the hand is rotated so that the palms point towards the legs and the thumb side points upwards. At the beginning of the recovery phase of the one arm, the other arm begins its pull phase. The recovering arm is moved in a semicircle straight over the shoulders to the front. During this recovery, the palm rotates so that the small finger enters the water first and the palms point outward. After a short gliding phase, the cycle repeats with the preparation for the next pull phase.
A variant is to move both arms synchronized and not alternating, similar to an upside down butterfly stroke. This is easier to coordinate, and the peak speed during the combined pull and push phase is faster, yet the speed is much slower during the combined recovery. The average speed will usually be less than the average speed of the alternating stroke.
Another variant is the old style way of swimming backstroke, were the arm movement formed a complete circle in a windmill type pattern. However, this style is nowadays no longer used for competitive swimming, as a lot of energy is spent on pushing the body up and down instead of forward.
It is also possible to move only one arm at a time, were one arm moves through the push, pull and recovery phase while the other arm rests. This is slow, but it is used frequently to teach students the movement, as they have to concentrate on only one arm.
The Leg Movement
The leg movement in backstroke is similar to the flutter kick in front crawl. They make a small contribution to the forward speed, yet are very significant for stabilizing the body.
The leg stroke is also alternating, with one leg sinking down straight to about 30 degree out of the horizontal. From this position the leg makes a fast kick upward, slightly bending the knee at the beginning and then stretching it again in the horizontal. This can be compared to kicking a soccer ball, i.e. kicking the water surface. The feet can be bent a little bit inward, yet they should be relaxed. Many students make the mistake of bending the legs too much. Normally, there are six kicks (3 per side) per cycle. However, there are also frequent variants with four or only two kicks per cycle. Usually, sprinters tend to use 6 kicks per cycle, whereas long distance swimmer may use less.
It is also possible to use a breaststroke kick or a butterfly (dolphin) kick, although this is rare except the butterfly kick after the start and the turns. Breaststroke kicks are most comfortable if the arms are used synchronized, as the breaststroke kick has difficulty to compensate for a rolling movement due to alternating arm cycles. The butterfly kick can be done slightly to one side depending on the rolling of the body.
Breathing
Breathing in backstroke is very easy, as the mouth and nose are almost always over water. Competitive swimmers breathe in through the mouth during the recovery of one arm, and breathe out through the mouth and nose during the pull and push phase. This is done to clear the nose of water.
Body Movement
Due to the asynchronous movement of the arms, there is a roll of the body around its own axis. This is normal and helps swimming effectively. The overall position of the body is straight in the horizontal to reduce drag. Beginners frequently let their posterior sink too low and increase drag.
Start
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The backstroke start is the only start from the water. The swimmer faces the wall and grabs part of the start block or the wall with his hands. Ideally, there are grips on the block for this purpose. The legs are placed in shoulder width onto the wall, with one leg slightly below the water surface and the other leg lower, both heels are slightly off the wall. The feet must be completely submerged. The moment before the start the swimmer pulls his head closer to the start block, while keeping the knees bent at a 90 degree angle.
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For the takeoff, the swimmer pushes his hands away from the block, and swings his arms around sideways to the front. At the same time he throws his head to the back. Only a minimal delay afterwards, the swimmer pushes himself away from the wall with his feet. Ideally, the swimmers back is arched during the airborne phase so that only the feet and the hands touch the water while the rest of the body is above the water line. This reduces the drag and allows the swimmer to start faster.
After the start, the swimmer is completely underwater. Due to the increased resistance at the surface, the swimmer should stay underwater as long as possible, up to the limit of 15m. Most swimmers swim a butterfly kick under water, as this provides more forward movement than the flutter kick. The underwater phase includes the risk of water entering the nose, which gives an unpleasant feeling. Most swimmers breathe out slightly through the nose to stop water from entering. It is also possible to use a nose clip. Some swimmers can close their nostril with their upper lips.
The swimmer must break the surface after 15m. The swimmer starts swimming with one arm, followed by the other arm with half a cycle delay. The swimmer continues in regular swimming style, staying on the back for the entire time except the turns. One part of the swimmer must break the surface at any time.
Turn and Finish
Approaching the wall has the problem that the swimmer cannot see where he is going. Most competitive swimmer know how many strokes they need for a lane, or at least how many stroke after the signal flags or the change in color of the separating lines. Turning the head is also possible, but slows the swimmer down.
When approaching the wall, the swimmer is allowed to turn to the breast and make one push/pull phase with one or both arms. Next the swimmer makes half a tumble turn forward, resting the feet against the wall. The arms are in the forward position at this time, and the swimmer pushes him off the wall. Similar to the start, the swimmer can remain up to 15m under water, with most swimmers using a butterfly kick for speed.
For the finish, the swimmer must touch the wall while lying on his back, less than 90 degrees out of the horizontal.
Competitions
There are three common distances swum in competitive backstroke swimming, both over either a long course (50m pool) or a short course (25m pool). Of course, other distances are also swum on occasions.
- 50m Backstroke
- 100m Backstroke
- 200m Backstroke
Backstroke is also part of the medley over the following distances:
- 100m Individual Medley (short 25m pool only)
- 200m Individual Medley
- 400m Individual Medley
- 4*100m Medley Relay
These are the official FINA rules. They apply to swimmers during official swimming competitions.
- Prior to the starting signal, the swimmers shall line up in the water facing the starting end, with both hands holding the starting grips. The feet, including the toes, shall be under the surface of the water. Standing in or on the gutter or bending the toes over the lip of the gutter is prohibited.
- At the signal for starting and after turning the swimmer shall push off and swim upon his back throughout the race except when executing a turn as set forth in SW 6.4. The normal position on the back can include a roll movement of the body up to, but not including 90 degrees from horizontal. The position of the head is not relevant.
- Some part of the swimmer must break the surface of the water throughout the race. It shall be permissible for the swimmer to be completely submerged during the turn, at the finish and for a distance of not more than 15 meters after the start and each turn. By that point the head must have broken the surface.
- During the turn the shoulders may be turned over the vertical to the breast after which a continuous single arm pull or a continuous simultaneous double arm pull may be used to initiate the turn. Once the body has left the position on the back, any kick or arm pull must be part of the continuous turning action. The swimmer must have returned to the position on the back upon leaving the wall. When executing the turn there must be a touch of the wall with some part of the swimmer’s body.
- Upon the finish of the race the swimmer must touch the wall while on the back. The body may be submerged at the touch.
External link
- Swim.ee (http://www.swim.ee/models/models.html): Detailed discussion of swimming techniques and speeds