Decryption： How to crush the diving splash into the water？ There are seven important links.

　　In the diving field, China team has the reputation of "Dream Team". A diving action completed in a few seconds, the average audience usually sees the effect of entering the water, that is, the size of the splash. In fact, splashing is also a high-precision technology. A reporter from Beijing Morning Post recently invited Yu Fen, head coach of Tsinghua diving team, to give a detailed answer to this technology.

　　Hand shape

　　There are slight differences between China and foreign countries.

　　In the diving competition, watching the slow-motion replay will find that the athletes enter the water with their palms in contact with the water surface, not the fingertips as generally believed. A "technical post" circulating on the Internet explains that water spray belongs to the category of fluid mechanics, that is, the process of collision between solid and fluid. Entering the water with your fingertips is equivalent to forming a wedge, so when you fall into the pool, you will find a way out along the direction of least resistance because of the incompressibility of water, and the inclined plane of the wedge is this direction. However, when the object colliding with water has a certain cross section, the water mainly moves laterally, and it can’t be rushed up due to the pressure of the surrounding water, which is the reason why the palm spray is small.

　　Yu Fen introduced that in the past 40 years, the technology of pressing the splash with the palm of your hand has been widely used in countries with relatively advanced diving. "We call it the palm-turning technology. The main point of action is to point your palm at the point where you want to enter the water at the moment of entering the water, and hold the other hand with one hand. " This is the hand type commonly used by athletes in China, while some foreign athletes will put their thumbs together, their fingers open and their hands crossed when entering the water, with their palms facing the water. In addition, there are two unusual hand types: one is that the five fingers are open, and the two hands are kept at a distance of about 10 cm; the other is that the two thumbs are clasped, the fingers are bent and the palms are facing the water.

　　posture

　　Splash suppression is not just about hands.

　　Yu Fen told the Beijing Morning Post that the hand shape is only one of the details of the entry action, but it is not the only criterion to judge the entry effect, which determines that the entry action needs a series of essentials.

　　"Simply put, the athlete’s body should enter the water perpendicular to the water surface. The specific requirements are that the arms should be close to the ears, and the head, shoulders and toes should be in a straight line. At the moment when the palm touches the water, the body should be in a straight line of 90 degrees with the water, and the waist should not be loose, and the buttocks should be clamped. Sometimes you can see athletes appear when they enter the water ‘ Passed ’ Or ‘ Not enough ’ Phenomenon, the water is very big, and the completion of the branch is very low. The reason for this phenomenon is not necessarily that the water entry technology is not done well, and problems often appear in the air. The specific reasons need to be analyzed in detail. "

　　In fact, when entering the water from a 10-meter platform, the instantaneous speed reaches 15 meters per second. Because it is difficult to completely stop the rotation of the body in the air when entering the water, the palm needs to adjust its direction, not just parallel to the water. This is to avoid injury. Yu Fen introduced that on the basis of mastering the essentials, athletes also need to protect themselves through minor adjustments.

　　opportunity

　　Opening time affects the effect

　　"As mentioned earlier, there is a problem with the water entry effect, and we can’t just find problems from this link. As the last link in diving, the technique of splashing can really attract the attention of ordinary audience, but it is difficult to make it clear simply by talking about this link, just as athletes can’t just practice splashing. When they are training, if there is a problem in one link, they will have to re-enter the springboard or platform, and all the processes will be repeated. "

　　Yu Fen introduced that the whole process of diving is divided into seven links from the beginning of the athlete’s running platform or walking board to the end when the toes are completely below the water surface. "They are all interlocking. If one link is not done well, it will directly affect the back until it enters the water." Although when watching the diving competition, I sometimes hear the commentary mention that "the splash effect is ok, and it can be somewhat remedied", but judging an action, flaws and mistakes still cannot escape the eyes of the referee.

　　"Every movement has to go through thousands of exercises before it can be polished to the best. Before pressing the spray, the forming time of the action is also very important, which is what we call ‘ Open the opportunity ’ If it is opened too early, the athletes will stay in the air for a long time and cannot concentrate their strength completely; If it is too late, there is no time to adjust your body to the best position angle. "

　　give a mark

　　The referee won’t just stare at the splash.

　　Similarly, the referee’s score should also be based on the whole process of the diver’s completion of the action. "Not to say that in the end, the referee will give him points. (The splash is not pressed well) it does have an impact, but if the air attitude and the angle of entry are well done from the beginning of the take-off, this action can still be considered successful and the score can still be higher. "

　　There is an important message in the scoring of diving rules: the judge will evaluate the score according to the athlete’s run-up (i.e., running board and platform), take-off, air and water entry, and also explain the integrity of the scoring process. Therefore, athletes should run smoothly during the competition, take off decisively and forcefully, take off at an appropriate angle and with a certain height; Beautiful posture in the air, tumbling and turning quickly; When a person dives, his body is perpendicular to the water surface, and the smaller the splash, the better. Yu Fen said: "In fact, from the moment an athlete appears, the referee begins to score his temperament, including every detail of the completion of the action. From the training, we require athletes to do every detail in order to conquer the referee in the official competition. "

　　■ knowledge post

　　Introduction action "jumping popsicle"

　　It’s hard to dance well.

　　It is said that some people accidentally discovered in the "popsicle" diving that it is better to use the soles of their feet instead of stretching their toes, so they brought water impact’s splash pressing technology. And "popsicle" is just the enlightenment action of zero-based diving. You don’t need to stand upside down, just straighten up and jump into the water. This action is easy to say, and it takes time and energy to train it well. As Yu Fen, head coach of Tsinghua University Diving Team, said: Diving is a sport in which people exert their control over their bodies to the extreme.

　　The correct posture of "popsicle" diving is: standing in front of the platform, arms open and body in a T-shape; At the moment of jumping out of the platform, your feet should be off the ground at the same time, your arms should be lifted up and your body should be y-shaped; When entering the water, the arm should draw an O-shape in the air, and finally put the arm close to the thigh and enter the water. The whole action is completed in a few seconds, and you also need to control your body. In the star diving programs in the previous two years, the zero-based stars were in a lot of situations when they completed this basic movement, and even appeared "slamming the door", that is, the body slammed into the water. If you don’t control your limbs properly, you are most likely to break the door panel, causing bruises and redness. Some experts have analyzed that if you fall into the water from a 10-meter platform, it is equivalent to falling vertically from a height of 1 meter on the plastic playground.

　　At the same time, the stars participating in the program are all adults, and even tall models. The selection of materials for diving enlightenment training requires moderate height, small pelvis and light body. It was only after the full development that I began to contact diving, and the star diving program was really beyond my power.