About Opentopia
Opentopia Directory Encyclopedia Tools

Butterfly stroke

Encyclopedia : B : BU : BUT : Butterfly stroke

  1. redirect
The butterfly, (fly for short) is a swimming stroke swum on the breast, with both arms moving simultaneously. The butterfly kick was developed separately, and is also known as the dolphin. While other styles like the breaststroke, front crawl, or backstroke can be swum easily even by beginners, the butterfly requires very good technique to be feasible. Most students consider it the most difficult style. It is the newest swimming style swum in competition, first swum around 1934.

Contents

Speed and Ergonomics

Side view of butterfly swimming
Enlarge
Side view of butterfly swimming

The butterfly is the second fastest style after the front crawl, and is the fastest style regulated by FINA. The speed of top swimmers is around 1.98 m/s, close to the speed of front crawl swimmers (2.17 m/s), and faster than the backstroke (1.84 m/s) and the breaststroke (1.67 m/s). The peak speed of the butterfly is even faster than that of the front crawl, due to the synchronous pull/push with both arms, yet since speed drops significantly during the recovery phase, it is overall slightly slower than the front crawl.

The breaststroke, backstroke, and front crawl can all be swum easily even if the swimmer's technique is flawed. The butterfly, however, is unforgiving of mistakes in style; it is very difficult to overcome a bad butterfly style with brute strength. Most people consider it the most difficult style to swim, yet done correctly competitive butterfly swimming requires less energy than the breaststroke. The main difficulties for students are the synchronous over-water recovery, especially when combined with breathing, since both arms, the head, and parts of the shoulder have to be lifted out of the water for these tasks.

History

The butterfly style evolved from the breaststroke. David Armbruster, swimming coach at the University of Iowa, researched the breaststroke, especially considering the problem of drag due to the underwater recovery. In 1934 Armbruster refined a method to bring the arms forward over the water in a breaststroke. He called this style butterfly. While the butterfly was difficult, it brought a great improvement in speed. One year later, in 1935, Jack Seig, a swimmer also from the University of Iowa, developed a kick technique involving swimming on his side and beating his legs in unison, similar to a fish tail, and then modified the technique afterward to swim it face down. He called this style Dolphin fishtail kick. Armbruster and Sieg quickly found that combining these techniques created a very fast swimming style consisting of butterfly arms with two dolphin kicks per cycle. Nowadays, the entire style is referred to as butterfly, but sometimes still also called dolphin, especially when referring to the dolphin kick.

This new style was considerably faster than a regular breaststroke. Using this technique Sieg swam 100 yards in 1:00.2. However the dolphin fishtail kick violated the rules of the FINA and was not allowed. Therefore, the butterfly arms with a breaststroke kick were used by a few swimmers in the 1936 Summer Olympics in Berlin for the breaststroke competitions. In 1938, almost every breaststroke swimmer was using this butterfly style, yet this stroke was considered a variant of the breaststroke until 1952, when it was accepted as a separate style with a set of rules by the FINA. The 1956 Summer Olympics were the first Olympic games where the butterfly was swum as a separate competition, 100 m (women) and 200 m (men).

(see History of swimming)

Technique

The butterfly technique with the dolphin kick consists of synchronous arm movement with a synchronous leg kick. Good technique is crucial to swim this style effectively. The wave-like body movement is also very significant, as this is the key to easy synchronous over-water recovery and breathing.

In the initial position, the swimmer lies on the breast, the arms are stretched to the front, and the legs are extended to the back.

The Arm Movement

The butterfly stroke has three major parts, the pull, the push, and the recovery. These can also be further subdivided. From the initial position, the arm movement starts very similarly to the breast stroke. At the beginning the hands sink a little bit down with the palms facing outwards and slightly down at shoulder width, then the hands move out to create a Y. This is called catching the water. The pull movement follows a semicircle with the elbow higher than the hand and the hand pointing towards the body center and downward. The semicircle ends in front of the chin, with the hands close together so the swimmer can form a triangle with his fingers.

The push pushes the palm backward through the water underneath the body at the beginning and at the side of the body at the end of the push. The swimmer only pushes the arms 1/3 of the way to the hips, making it easier to enter into the recover and making the recovery shorter. The movement increases speed throughout the pull/push phase until the hand is the fastest at the end of the push. This step is called the release and is crucial for the recovery. The speed at the end of the push is used to help with the recovery.

The recovery swings the arms sideways across the water surface to the front, with the elbows slightly higher than the hands and shoulders. The arms have to be swung forward fast in order to bring them to the front over the water. It is important not to enter the water too early, because this would generate extra resistance as the arms moved forward in the water against the swimming direction. A high elbow recovery, as in front crawl, would save more energy, yet the movement restrictions in the shoulders do not allow this easily, and due to the synchronized movement it is not possible to roll around the shoulders as in front crawl.

The arms enter the water with the thumbs first at shoulder width. A wider entry loses movement in the next pull phase, and a smaller entry, where the hands touch, wastes energy. After a brief rest the cycle repeats with the pull phase.

The Leg Movement

The leg movement is similar to the leg movement in the front crawl, except the legs are synchronized and the entire body moves in a wave-like motion to assist the legs. The swimmer does not really kick in the butterfly; the legs follow the undulation of the body. The leg movement consists of two pulses per cycle. The first pulse comes when the hands enter the water and the second, stronger pulse comes at the middle of the push phase. The second pulse assists in the recovery of the arms.

Alternatively, it is possible to do only one pulse per cycle, but this is not advisable as it will make the recovery more difficult. Also, it is possible to swim butterfly arms with a breaststroke kick, where the main push of the kick comes at the middle of the push phase. This is not allowed by the FINA, but is sometimes done for training purposes. A breaststroke kick will not be as fast as the dolphin kick, but is a feasible swimming style.

Breathing

There is only a short window for breathing in the butterfly. If this window is missed, swimming becomes very difficult. Optimally, a butterfly swimmer synchronizes the taking of breaths with the undulation of the body to simplify the breathing process; doing this well requires some attention to butterfly stroke technique. The breathing process begins during the underwater "press" portion of the stroke. As the hands and forearms move underneath the chest, the body will naturally rise toward the surface of the water. With a minimum of effort, the swimmer can lift the head to break the surface fully. The swimmer breathes in through the mouth. Experienced swimmers continue looking toward the bottom of the pool while they inhale. This keeps the body balanced and in a straight line. The head goes back in the water after the arms come out of the water as they are swinging forward over the surface of the water. If the head stays out too long, the recovery is hindered. The swimmer breathes out through mouth and nose till the next breath.

Normally, a breath is taken every other stroke. This can be sustained over long distances. Breathing every stroke slows the swimmer down. Other intervals of breathing practiced by elite swimmers include the "two up, one down" approach in which the swimmer breathes for two successive strokes and then keeps the head in the water on the next stroke. Swimmers with good lung capacity might also breathe every 3rd stroke during sprints or the finish.

Body Movement

Swimming the arms or the legs separately is difficult, and correct body movement is crucial for the arms and legs to use their full potential. The body moves in a wave-like fashion, controlled by the arm movement. As the hands go in, the hips go up, and the posterior breaks the water surface. During the push phase the head goes up and the hips are at their lowest position. In this style, the second pulse in the cycle is stronger than the first pulse, as the second pulse is more in flow with the body movement.

Start

Regular swimming start
Enlarge
Regular swimming start

Butterfly uses the regular start for swimming. After the start a sliding phase follows under water, followed by dolphin kicks swum under water. Swimming under water reduces the drag from breaking the surface and is very economical. Rules allow for 15 m of underwater swimming, before the head must break the surface, and regular swimming begins.

Turn and Finish

During turns and during the finish, the hands must touch the wall at the same time on the breast. The swimmer touches the wall with both hands while bending the elbows slightly. The bent elbows allow the swimmer to push himself away from the wall and turning sideways. One hand leaves the wall to be moved to the front underwater. At the same time the legs are pulled closer and moved underneath of the body towards the wall. The second hand leaves the wall to be moved to the front over water. It is commonly referred to as an "over/under turn" or an "open turn." The legs touch the wall and the hands are at the front. The swimmer sinks under water and lays on the breast, or nearly so. Next the swimmer pushes himself off the wall, keeping a streamline position with the hands to the front. Similar to the start, the swimmer is allowed to swim 15m underwater before the head must break the surface. Most swimmers dolphin kick after an initial gliding phase.

The finish requires the swimmer to touch the wall with both hands at the same time.

Competitions

There are three common distances swum in competitive butterfly swimming, both over either a long course (50 m) or a short course (25 m pool). Of course, other distances are also swum on occasions.

The butterfly is also part of the Medley over the following distances:

These are the official FINA rules. They apply to swimmers during official swimming competitions.

Current world records

Long course swim pools

Men

Women

Short course swim pools

Men

Women

References

External links

 

From Wikipedia, the Free Encyclopedia. Original article here. Support Wikipedia by contributing or donating.
All text is available under the terms of the GNU Free Documentation License See Wikipedia Copyrights for details.

Search Titles
0123456789
ABCDEFGHIJ
KLMNOPQRST
UVWXYZ?

E-mail this article to:

Personal Message: