Swimming is the oldest form of movement on water, as evidenced by the images of swimming people, dated IV-II centuries BC. Later it acquired a sports orientation, and by the end of the 19th century it became an official sport in the program of Olympic competitions.
There are three fundamental varieties of swimming:
- crawl (on the back, on the stomach);
- butterfly stroke (dolphin);
- breaststroke.
Each of them has its own technique of performance, speed, features of proper breathing.
Swimming style butterfly stroke
Translated from English, “butterfly” means “butterfly”. Indeed, the swimmer, when lifting with a symmetrical flap of the upper limbs, resembles the movement of the wings of this elegant and beautiful insect.
Often the type of swimming butterfly stroke is identified with a dolphin. These are the most difficult styles, because when they are performed, almost all muscle groups are involved with their simultaneous work. Movement of the swimmer is carried out on the chest with parallel and symmetrical strong arms. In this case, the front part of the body emerges from the water, and the legs carry out undulating slides and blows in the water. In addition to special physical stress, butterfly and dolphin require the observance of a special breathing system, different from other styles. Each succession cycle consists of one stroke with hands, two shocks with legs, inhale and exhale.
For athletes, special qualification standards are established that are carried out in a 25- and 50-meter pool. According to them, for each time during which the swimmer is able to overcome the specified distance, the following can be assigned:
- discharge (I, II, III);
- title of candidate for master of sports (CCM);
- title of master of sports (MS);
- the title of master of sports of international class (MSMK).
What's the Difference
In the classic performance, butterfly legs are moving with a breaststroke (pulling up the hips with breeding the foot, pushing and joining the feet). Dolphin appeared with the improvement of butterfly stroke with a bias towards greater swiftness in overcoming distances. It is believed that slipping the legs in it is most natural.
Dolphin as a swimming style got its name due to the movements of the body of the athlete, similar to a real frolic dolphin. This is a high-speed butterfly type, in which the movement of the joined legs occurs in one plane, resembling the tail of a mammal.
Swimming technique
During execution, the muscles of the shoulder, triceps, back, abs, chest, hips, calves are involved. Due to so much muscle effort, the dolphin swimming style is considered the most energy-consuming of all. The body of the swimmer moves up and down during the entire route.
Starting position: the body is in a straight position, chest down, shoulders are parallel to the surface of the water, legs are connected, arms are straight ahead in front of the head.
When the upper body moves forward and down, the pelvis rises up, and the legs push and swiftly go down. Then there is a change: the shoulders rise, the hips and pelvis fall, the ankles fly up, making a blow. The angle of raising and lowering the body above water is 20 °.
The wave movements of the body are achieved due to the tension of the broad muscles of the back and abs. Teaching this style in swimming schools begins at the age of 12. Up to this age, butterfly stroke technique (like breaststroke) is very difficult to master.
Hand movement
The distribution of driving forces is as follows:
- 10% of physical effort falls on the legs;
- 90% of physical effort is directed to the hands.
As can be seen from the statistics, the hands perform the main work when swimming to give speed.
There are five phases of hand position in a single swimming cycle of the butterfly stroke type:
- Sweeping hands over the surface. At the same time, the arms straighten, performing a swing each on its own side, and the shoulder girdle is pushed out of the water. During the execution, the hands turn outward, they should be the first to touch the water at the end of the maneuver.
- Hand immersion. The butterflyist performs a jerk forward, pushing his shoulders and arms.
- The shock of the stroke. Hands in the water are bent, hands and forearms help to perform supporting swings, after which the hands are spread apart.
- The decisive phase of the stroke. The angle of bending of the hands reaches 90 °, during their energetic extension and pulling, active repulsion takes place. Further, the arms extend along the body, the hands are located in the hips.
- The hands relax, putting their hands above the water. The elbows should come out first.
Features of the legs
During the movement, the legs are located nearby and carry out continuous fluctuations in the region of the lower leg in the vertical plane up and down. The swimmer's body actively helps in making these vibrations. The first two attacks kick the shoulders above the water, the second two - the back.
The feet are at an angle of 45 ° in a medium-stressed state. Feet seem to turn into the tail of a dolphin, making precise hits.
Breath
The breathing technique when swimming with the dolphin style is associated with the position of the hands and their phase during work. The first phase (carrying over water) is considered more convenient for inspiration. Head and shoulders are in their highest position. The duration of the breath is about 0.5 seconds.
After inhalation, the face is immersed in water, arms and shoulders are lowered down. All the remaining time until a new phase is the expiratory time. This type of breathing is considered optimal for swimmers (on average, 50-60 breaths per minute).
However, professional athletes, due to the high speed of execution and in order to increase efficiency, can perform 2-3 full cycles of the position of the hands in one inhalation-exhalation.
How to learn to swim with a dolphin
It is best to train, hone skills and point out errors that will help in a swimming school. For self-mastering the technique, you can use the instructions:
- Train on land. Make wave-like body movements forward, starting with the head and following it with the whole body. Observe yourself in the mirror, when the movements are smooth and even, you can immerse yourself in water.
- When swimming in water, try to sway, repeating wave-like movements. This may not work out right away. When the position in the water becomes comfortable, proceed to the next step.
- Connect your legs and keep them close, not apart.
- So that your hands do not interfere with swimming, press them to the hips along the body. This position will allow you to swim faster.
- Perform movements, add hand swings, exercise longer. To improve the technique of swimming style "dolphin" in the initial training can help swimming board - hold on to it while moving.
- The driving force of a swimmer by a dolphin is 75% dependent on the flexibility of his ankles. By developing it, you will improve your technique and speed. The size of the ankle can also affect the longer it is, the more efficient the activity is.
Dolphin under water
In open waters, the dolphin swimming style is often used underwater. Some of its features:
- arms are extended with an “arrow” in front of you;
- legs and body perform wave-like movements, as in the usual version;
- a breath is taken before diving, usually with greater strength and volume;
- exhalation is done under the nose with water.
Execution errors
When learning to swim with the dolphin style, due to its complex technique, the following errors may occur:
- Incorrect or missing pelvic work. When viewed from the side, it seems as if the main movement is due to the work of the hands. But the wave-like movements of the body are important, this result is largely achieved due to the movement of the pelvis.
- Incorrect foot movements. It must be ensured that they are not too close to the surface of the water and do not rise from it. It is also important to control the synchronism of their work and the inadmissibility of flexion in the knee.
- Wrong hand work. When performing the "dolphin" technique, the arms should be shoulder width apart. The close location will not allow the mach to be performed more accurately, and a greater distance between the arms increases the resistance and takes the swimmer's strength.
- Violation of the rhythm of breathing. Performing inspiration at the right time on the rise while maintaining breathing and exhaling will help maintain an appropriate rhythm.