First, breaststroke body posture
In breaststroke, the body is not fixed in one position, but constantly changes with the movement of hands and legs. At the end of an action cycle, the body should spread out its chest, slightly tuck in its abdomen, slightly tuck in its waist, put its legs together, keep its arms as straight as possible, slightly tighten its neck, put its head between its arms, and keep its eyes on the front and below. The whole body should do ups and downs with the horizontal axis of the body as the axis (see the picture below).
Second, breaststroke leg technique
The leg movement of breaststroke is one of the main driving forces to push the body forward. Its main movement links can be divided into four stages: retracting legs, turning, pedaling and sliding. These links are closely connected and are complete movements.
The purpose of leg retraction is to create a favorable position for turning feet and kicking water, at the same time, to reduce resistance and consider the needs of hand-leg coordination factors. When you start to shrink your legs, your legs will naturally droop with inhalation. At the same time, your knees naturally gradually separate and your calves move forward. When recovering, relax your feet, keep your heels close to your hips, and separate them while retracting. The calf adduction is weak, and the calf and calf should be adducted within the projected cross section of the thigh to reduce the resistance during adduction (see the figure below).
After the calf is adducted, the thigh and trunk form an angle of about 120- 140 degrees (see the figure below), and the inner sides of both knees are the same width as the hip joint. The angle between the thigh and the calf is about 40-45, and the calf is vertical as far as possible, which can make favorable preparations for kicking the foot.
In breaststroke leg technique, the flip of the foot is very important, which directly affects the kicking effect. At the end of the leg retraction, the angle is still close to the hip. At this time, the knee joint is buckled inward, and the feet are turned outward at the same time, so that the inner sides of the feet and calves are aligned with the pedaling direction, so that the water surface can be increased at the same time, and the thighs can exert greater strength and make positive preparations. Shrinking legs, turning feet and kicking water are a continuous and complete action process. The correct anti-foot action begins before the leg is retracted and is completed when kicking the water. If you turn your feet and stop your hind legs a little, it will destroy the consistency of your movements and increase your resistance (see the picture below).
The effect of breaststroke kick is completely determined by the correct kick technique. Push the water from the thigh, first stretch the hip joint so that the calf is perpendicular to the favorable part of the water as far as possible, then push the water backwards, and then stretch the knee joint and ankle joint (see the figure below).
The action of kicking and catching water is actually a continuous and complete action, only kicking and catching water first. In fact, in the movement of turning feet, the knees are inward and the feet are outward, which has fixed the only direction of kicking water (see the picture below).
The effect of kicking and catching water depends not only on the route and direction of leg joint movement, but also on the size of water area, and the most important thing is the change of speed and intensity of kicking and catching water. The speed of pedaling and water clamping is from slow to fast, and the strength is from small to large.
After the water is caught, the feet are at the lowest point of the horizontal plane, which means that the body slides forward with the help of the power of pedaling, the waist is pressed down, and the feet are close to the water, ready for the next cycle (see the picture below).
Third, breaststroke arm technology
The stroke arm of breaststroke can produce great impetus. Mastering reasonable arm stroke technique and coordinating with leg and breathing movements can effectively improve swimming speed. Its main movements can be divided into several stages: starting posture, sliding down (also called "holding water" or "grabbing water"), paddling, crossing hands and reaching forward. These stages are also closely linked and complete actions.
At the end of the kick in the starting position, the arms should keep a certain tension, naturally straighten forward, parallel to the water surface, palms down, and fingers naturally close together, so that the body becomes a straight line and forms a better streamline.
Slide down from the starting position (catch the water), stretch your arms forward and move your center of gravity forward. At the same time, the shoulder joint is slightly pronated, the palms of both hands are slightly turned to the lower side of the outer oblique, and the hands are slightly flexed to press the water down. When the palms and forearms feel pressure, they start paddling. On the one hand, the action of catching water can create favorable conditions for paddling, on the other hand, it can also make the body float forward. The speed of catching water varies according to individual level. People with high water levels catch water quickly, and vice versa.
When the two hands are well connected to the water and the score is made at an angle of about 40-45 degrees, the wrist begins to bend gradually. At this time, the arms and hands gradually and actively bend their arms sideways, downwards and backwards. When paddling, the hand movements should be divided into two parts. The first part: the hand moves outward-downward-backward, and the water flows from the thumb to the little finger. The second part: the hand moves inward-downward-backward, and the water flows from the little finger to the thumb. When paddling, the bending angle of forearm and upper arm is constantly changing, and its standard is to exert the best strength. The elbow joint is higher than the hand during the whole stroke. The route of hand movement should not go to the back of the shoulder, but to the front of the shoulder (see figure). Its speed is from slow to fast, and it should reach the fastest speed when stopping.
Stopping is a continuation of the paddling stage. When you close your hand, the direction of action is inward, upward and forward. The attack angle of the hand is about 45 degrees. Due to the external rotation of the forearm, the palm gradually turns inward (see figure). The hand-closing action should be conducive to the rapid forward hand-reaching action, and the elbow joint should be consciously clamped inward. When the hand retracts to the front and lower part of the head, the palms of both hands turn from the back to the upper position, so that the arm does not exceed the extension line outside the shoulder. Hands should be active, fast and smooth during the whole closing action. At the end of closing, the elbow joint should be lower than the hand, and the angle between the big arm and the small arm should be less than 90 degrees.
Stretch your arm forward. The arm is stretched forward by straightening the elbow and shoulder joint. The palms gradually turn inward from the beginning, extend forward together, and then turn down gradually before the end. The action route of the whole arm of breaststroke is oval from above or overlooking, which is a coherent and complete process, with strength from small to large and speed from slow to fast.
Fourthly, the coordination technique of breaststroke.
When the arm slides down (grabbing the water), it begins to look up gradually, and then the legs keep a natural relaxed and straight posture. When the arm is paddling, the head is raised until the eyes are above the water and the legs are still motionless. Only when you stop, do you start to close your legs and lean forward slightly. At this time, raise your head to the surface of your mouth and inhale quickly and forcefully. Bow your head when you reach your arm, exhale through your nose or nose and mouth, and push and hold the water when your arm reaches nearly half position. After that, let the body stretch and slide for a certain distance, and then make a second cycle when the pedal speed decreases (as shown in the figure).
In the process of breaststroke, it is generally a breathing cycle, which is beneficial to the aerobic supply of the body, thus reducing the fatigue rate. It should be noted that before looking up and inhaling, all the waste gas in the body must be spit out, so that fresh oxygen can be inhaled.