The Su God of the Reopening of the Sports Arena

Chapter 890 Technical review, new technology released!
The technical analysis room of Ersha Island.

A group of people were watching the Bolt video, nodding from time to time.

This is the latest data analysis established by Randy and Ralph Mann after the champion model analysis.

Some fixed-frame data are printed above:

The conversion speed of the excitation and inhibition of the motor center of the cerebral cortex, that is, the flexibility of the nerve process According to the data, the fastest exchange frequency of the legs when running on the way is 3.1 to 4.85 times per second.This can be said to be very rare in his height.

Because such tall athletes are generally of the stride type, and Bolt is obviously a "special case".

He is actually the type of stride frequency, the key is... His stride length is basically due to physiological reasons.

①Pushing force: the formula of F=mv/t(∵F=ma;a=(v-v0)/t and ∵v0=0 ∴a=v/t ), since m here represents the mass of the human body and is a constant , so the greater the force (F) of back pedaling per unit time, the greater the forward speed (v) of the human body.

②Pushing speed: If the kicking force (F) is constant, the speed (v) is inversely proportional to the time (t) of kicking off the ground, that is to say, the shorter the time of kicking off the ground, the faster the obtained speed big.

③The degree of leg straightness: mainly manifested in the alignment of the three joints of the hip, knee, and ankle, so that the reaction force of the ground to the human body can fully push the body forward through the center of gravity of the human body.

④Pushing angle: Due to the characteristics of the human body structure, the back kicking angle is limited. Reducing the back kicking angle is not only conducive to increasing the horizontal component force, but also reducing the ups and downs of the body's center of gravity.In addition, reducing the kick angle is also an important factor to speed up the frequency of leg exchange.

⑤The force direction of the back pedal: the direction of the force of the back pedal should be consistent with the forward direction. If the direction of the force of the back pedal is to the left or to the right, a force component will be generated, which will reduce the forward speed and affect the linearity of the center of gravity movement of the body.

Then bring in Bolt's physical data and competitive data one by one.

Under the "championship model" display, Bolt's various data changes in the final of the Beijing Olympic Games:
The applied force F/N is 804.7, a substantial ↑ increase compared to the previous 2007.

The maximum speed is 12.04s, which is also significantly improved compared to the previous year.

The starting acceleration is 9.36, which is still a significant improvement.

The peak output power is 2554.35, nearly a hundred points higher than last year.

The overall work done was 80.465, compared to ↑ in 07.

The work efficiency is 6.235, which is still a sharp increase in unit efficiency compared to 07.

Front swing angle/° of swing leg at the start of hip delivery: 62.3.

At the end of the hip delivery, the forward swing angle of the leg/°: 77.

Swing leg swing angle/° from the beginning to the end of hip delivery: 14.7.

Front knee joint fan angle/°: 50.8.

Front knee joint fan angle/° at the end of swinging legs: 78.3.

Knee fan angle difference between start of hip delivery and end of hip delivery: 27.5.

……

Seeing the dense data displayed on the big screen, even these "battle-tested" veterans and coaches feel that these data are too... detailed.

The summary of the previous competitions, compared with this one, is basically at the level of elementary school students.

"I used 41.25 steps in the Olympics." Randy watched the video on it, and moved the progress bar bit by bit: "It is 2-6 steps less than other players, which shows Bolt's super strong step length ability. Frequency + step length, he is currently the most perfect one."

"The knee angles of Bolt's supporting legs at the moment of landing and in the vertical phase of the Olympic Games are 157.1° and 146.8° respectively."

"The launch path has very little deviation and is fairly straight."

"As the knee moves forward, his hip rotates inward and there's a lot of lateral weight shift."

"His starting posture is obviously not compact enough, but unconventional and a little relaxed."

"I think it's a compensatory strategy he employed to maximize the initial velocity of force generation at the beginning."

"Look at Bolt's scrambling." Randy clicked on the video, played it for a while, and then paused again: "Look at his scrambling feet, the change of the center of gravity, he doesn't seem to put his feet on the center of gravity Under the hood, I think the only time he might drop his center of gravity is at the start. This means, because the closer the foot is to the center of gravity, the faster the person can complete the running cycle, and the faster the time."

"There's also the issue of Bolt's hip back," Randy said. "I think that's the key."

"Many of our athletes place too much emphasis on stride frequency and neglect full hip movement, and as a result, power is lost during progressively decreasing stride lengths, compromising performance."

"There is also Bolt's vertical oscillation, which is very small." Randy tapped a corner of the screen with a small wooden stick, just facing Bolt's running posture: "Because the smallest vertical oscillation usually reduces the stress on the joints , and improve efficiency during operation.”

"These are some points that we have neglected in our training."

……

"Okay, let's take a look at the comparison of the data of our athletes in this Olympic Games." Randy posted a photo of Lao Yi on it, and said: "First of all, we don't have too many problems in terms of physiology for Lao Yi's future positioning. Bolt is 25cm shorter in height, but we can see that even so, Law's stride index is still 1.249, surpassing Bolt's 1.245. This shows that Law should indeed focus on stride flow , and the stride frequency is an auxiliary. It also reveals a major reason why Lao's late course is so strong."

Can Laoyi surpass Bolt in stride index?It really is.

But if this is in the previous country, no one would dare to talk nonsense.

I am afraid that if the judgment is wrong, it will usher in a huge public opinion attack.

"But while Law has an excellent stride index, his stride frequency index is quite bad." Randy carefully analyzed the data model for all Ersha Island coaches and athletes: " By 0.554."

"Lao, your future not only needs to be strengthened, but your entire stride frequency must also be strengthened, so that you can run faster."

Although Lao Yi didn't quite understand, when it came to himself, he still listened more carefully than ever.

In order not to give up the fourth [-]-meter top spot on Ersha Island, which I managed to get along with, just like this.

"Running on the way, your landing angle ratio is 65.3, which is five or six percentage points less than Bolt. And the smaller the landing angle, it actually means that there is still a lot of potential to be tapped for Lao's 'grabbing technique'." An analysis is displayed on the screen, which reads: A small landing angle means that the vertical projection point of the center of gravity of a person is farther away from the landing point, which will inevitably produce a greater supporting reaction force opposite to the running direction, resulting in a loss of speed in the horizontal direction and affecting running speed.

The knee angle of the supporting leg is changed from 148.3 to 140.4.

In this way, the change range of the two movements of work and rest is too small, only 7.9.

Usain Bolt's knee angle changes in these two technical movements are the most obvious. His data is directly more than double that of Lao Yi.This shows that Bolt's supporting leg muscles retreat more actively, and because of this, the active muscles of the supporting leg are passively elongated during the buffer period, the initial length of the muscle increases, and the contact area between the cross bridge and the site increases, resulting in an increase in muscle tension.As a result, the direction can be changed to keep Bolt's muscles in the kickback stage, and exert greater contraction strength and speed.

How to operate it specifically, Randy looked at Su Shen below and asked him to come up and explain together.

Su Shen was not polite either, and walked up to Lao Yi in the audience, and said, "The next thing you have to do is to speed up the swinging speed of your swinging legs, which can effectively improve the cushioning and kicking and stretching speed, and can also shorten the game time." , and finally get a strategy to increase the stride frequency."

"Daniel, the minimum knee angle of your swinging leg is 25.5. It can be seen that your swinging leg is not folded enough, which will affect your forwardness. This year until the end of winter training, your swinging leg folding technique will have to be reworked. Concentrate, remember to use the swing to promote the kick as much as possible, and combine the kick with the swing."

"Okay, I know Brother Xiaotian." Hearing this, Lao Yi silently took notes.

Although he may not be that good in theoretical knowledge, Randy's method of replacing data with video and then adding text analysis allows many players who are not so good at digesting theoretical knowledge to quickly enter the state.

Know where you went wrong and where you need to improve.

"Brother Kai, this is the data of your Olympic shots, especially in the vertical stage at the moment of landing. Bolt's knee angle changes by close to 20. And you, Brother Kai, are only in the early 10s. This shows that the supporting legs contract from eccentric to radial. Heart contraction, brother Kai, you haven't done enough. There is still room for improvement."

"Looking at the distribution of your stride frequency and stride length over the entire 100 meters, the front is still a little too fast." Su Shen said: "This will prevent your rear from showing its true perfection, and the overall performance will be less optimized. Slower. Especially between No.11 and No.15 steps, the instability is more obvious. If you can stabilize, you may improve your grades in the future.”

Hu Kai also pushed his glasses.

Looking at his own running data on the entire projection screen, he also nodded silently after reading it patiently.

There was no such detailed data analysis system before.

Therefore, even the coach can only look at the feeling.

But now Randy has brought science and systematization, and the observability of the team has been greatly improved at once.

Under the champion system model, Hu Kai has a clearer and more visible understanding of his own shortcomings.

It's really clear at a glance.

New players don't care, they don't know enough about this system, and they don't have deep feelings.

But for the old players, they can clearly feel the earth-shaking "change" in the post-match replay.

The previous "post-match review" was not so detailed, but now... everyone has a lot of things to remember.

This is the benefit of being systematic and scientific.

It is enough to be clear, clear, what the athlete wants to improve, and sometimes even look at the gaps in the data.

……

"Haohuan, let's take a look at your data. You are about five centimeters shorter than Bolt, but as a big man over 1.9 meters, the angle between your legs and the angle of your swinging legs are similar to Bolt's. There is a clear difference between Bolt. Bolt’s legs angle and swing leg angle in this final run were 96.8 and 12.1 respectively, while yours was 100 and 11.1, which shows a point.” Su Shen nodded and continued Play button, which shows another line of analysis, saying: "Your back kick, back kick knee angle, and your support time are too long in the back kick phase, so your leg angle and swing leg angle are weak. Yu Bolt."

"Even considering the physiological segmentation curve, we think that if you correct this aspect, it should be faster."

"The specific method is to strengthen your scissors legs, appropriately reduce the angle of the back kick, and shorten your support time. This is the analysis of the champion model we calculated based on your four-shot [-]-meter shot in this Olympic Games."

Zhao Haohuan looked at it, touched his chin with his hand, and compared it intuitively, when he and Bolt were put together, he could indeed see many problems under the high-definition close-up lens.And compared with the past, the current adjustment is more detailed and more high-end.

This is an adjustment after the athlete has progressed to a higher level.

It is no longer just a simple adjustment of a certain technical action.

Each of these physical data may have to be compared and checked one by one.

As for why Bolt is used.

Needless to say.

Because Bolt is the fastest.

Not only now, but in the original timeline, Bolt was pulled out countless times for analysis and comparison.

If a person runs the fastest, then any set of his running data has the significance of absorbing, analyzing and referring to the scientific data model.This is why Su Shen must introduce the "Champion Model Theory" to the country.

Otherwise, there is no theoretical guidance of a scientific data model, just relying on the so-called coaches' experience summaries.

It's just too dated.

In Randy’s original words in later generations——

"I often tell some coaches, don't argue with me about scientific issues. What I'm telling you now is something that scientists all over the world have approved. You just need to follow it. If you don't train psychology and biochemistry Human mechanics, etc. Wait for the integration of these scientific knowledge, you can not create a new training system, this is basic common sense."

"Education is not to encourage the coaches of flower growers to study in the United States, because a lot of knowledge is placed there, and it is all in Chinese. It only needs the coaches to go to the classroom to study systematically... I think the flower growers should let all the coaches participate in scientific training. , If they do not go through classroom training, they will not be given a diploma. Let the coaches understand that this is my profession, and all our coaches must be professional."

Referring to this passage from Randy, to truly scientificize training and get out of the "experiential training doctrine" that has dominated the track and field training system for decades or even longer, you must have a real scientific reserve.And it's not just one person, it needs many smart minds to work together.

After all, a person's mind always has a limit.

Even Su Shen himself, if it wasn't for reopening, then he wouldn't be able to finish so many things by himself.

And in the later stage, even he needs a strong and stable team and laboratory to constantly innovate.

The most taboo thing about sports science is to be complacent.

Think that what is the best, and then stop going beyond and breaking through, so that the meaning of scientific movement will be lost.

"It's me in the end." Su Shen asked Randy and the others to come back, but Randy waved his hand and refused.

Because Randy and Ralph Mann hope that God Su can come by himself.

For them, bringing out a few outstanding athletes has a high sense of accomplishment, but...the highest sense of accomplishment is to help a country build an overall scientific sports system.And these, in the end, still need natives to operate.

Seeing the two people saying this, Su Shen had nothing to say. He nodded and continued to say to the playing video: "This is my four shots in 100 meters this time."

"As you can see, from the preliminaries to the finals, within four shots, the number of steps has actually increased slightly, the average stride frequency has also increased, but the average stride length has shrunk. That is to say, my stride frequency index has gradually increased. As the game progresses, the step length index shrinks.”

"The following shows the step-by-step changes in my 4-meter run of the Beiao [-] guns, which can be divided into two situations: one is the three stages of frequency increase-maintenance-decline after the start, showing an inverted "V "Font. Another situation is to increase the frequency after the start-maintain-decrease-repeat-re-decline, and the trend of the pace frequency change in the whole process presents an "M" shape."

"Considering the relationship between excitement and inhibition of the nervous system, the high stride frequency running method often cannot occur many times and maintain a very high stride frequency during the whole process of fast running. Considering that the former mainly appears in the preliminaries and rematches, The subsequent semi-finals and finals are all M-shaped, so I think the latter type may be more meaningful for research under the current physiological conditions in high-intensity confrontation."

"And now it's also comparing Bolt." Su Shen pressed the pause button, and the running picture of himself and Bolt appeared on the big screen, and said: "We can see that Bolt won the Beijing Olympic Games. From the 6th step to the 35th step, the stride frequency is constant for a long period of time or distance during the 60-meter run. However, the rest of the runners, including myself, have relatively large strides in these segments. It fluctuates up and down. In my words, especially after [-] meters, the fluctuation becomes more obvious."

"Then what does the smaller fluctuation mean? Look at this set of data. When Bailey broke the world record, the whole step frequency changed very little. It reached 0. 1, and kept it until 10 meters. From 4 to 63 meters, his stride frequency rose to 30. 30 steps per second, and in the last 60 to 4 meters, his stride frequency returned to 72. 60 steps per second. "Su Shen looked at the big screen seriously and said: "So his whole pace change line is almost a horizontal line."

"Then we have to put forward a hypothesis. Compared with other players, Bolt's stride frequency is lower throughout the whole process. Can the lower stride frequency be maintained for a longer period of time without fatigue?" Clicking the mouse, Su Shendao: "Although Bolt is a stride type, his stride length is naturally large due to his physiological conditions. For example, he runs 40.5 steps for a 49 meters, while others run 80 steps. From the perspective of energy distribution, you only need Run about 30% of his distance. According to the data, we can find that no matter whether it is a Chinese athlete or a foreign athlete, as long as the six-second rule is correctly activated, most of the athletes will start at step 34-27. Slow down. If you have a long stride, you will reach 60 meters in 80 steps, then you may not enter the physiological natural deceleration stage mentioned above until you are 32 meters away. If you have a small stride, you will reach 60 meters in 65 steps. You will naturally start to slow down at about [-] meters. Due to the excitation and inhibition mechanism of the nervous system, it is impossible for a person to maintain a high frequency for a long time, and the [-]-meter run can only be completed by raising and lowering the frequency throughout the whole process, so How to stabilize has become a key."

"But is it true that the bigger the stride, the better?" Su Shen looked down and said, "That's definitely not the case."

"Because even in terms of stride, it is not impossible to surpass Bolt, such as Bloomfield (39 and a half steps in [-] meters). If you consider the physiological proportion of the human body, look at the stride index, Gatlin, Bailey. Paul, Mike Rogers, etc. are better than Bolt. Therefore, the idea of ​​simply expanding the stride length in China is not suitable for everyone. The combination of stride frequency + stride length is the best way to reduce and eliminate redundant "stride length expansion". Good. After all, the essence of modern sprinting is the relaxation technique in high-speed displacement based on pedaling, so we must determine that the future trend is to create different golden stride-frequency ratios for each person according to the physiological conditions of the individual human body."

"Our country has fallen into a situation where people usually regard step length and stride frequency as the "cause" and running speed as the "effect". Speed." Su Shen said: "Most people start from the perspective of optimizing stride frequency and stride length, and conduct research on the improvement of special speed. But in fact, there is no direct causal relationship between stride frequency, stride length and specific speed. Running Speed ​​is a kinematic parameter of the horizontal displacement of the body center of gravity when the athlete is running, but step length and stride frequency are parameters of the spatio-temporal structure, and the two sides describe the kinematic indicators of the athlete's running from different angles."

"Then how to do it is the most reasonable? There have been similar sayings for a long time, such as reasonable speed = athlete's maximum stride length 94.12.9% x maximum stride frequency 95.1 ± 3.5%. Therefore, in the future, we will also work hard on the research of mathematical models If you want to consciously promote the increase of step length and the reduction of single-step time, in fact, the continuity of running power and the systematic and cooperative force of each link must be destroyed, which will have a negative impact on the running speed of the human body. In fact, for sprinters, their running speed is mainly affected by their high-speed running relaxation ability and high-speed swing ability. It will be more scientific and systematic if it conducts in-depth exploration.”

Randy was listening below, nodded and said: "Is the whole person operating as a whole machine? This point of view is interesting. Right, old man."

Just as he was talking, he saw Ralph Mann lost in thought.

Didn't take care of Randy next to him at all.

Because Su Shen’s statement provided him with a new way of thinking. It is true that everyone pays too much attention to the study of the simple stride frequency and speed. In fact, they forget that the body is a whole, and it is the most precise body in the world instrument.If we study it as a whole, will we be able to discover more paths and methods in the future?
"Looking at myself again, the moment of the Olympic landing and the vertical stage of Bolt's supporting leg knee angle, in fact, we can clearly see that because of my physical fitness and performance, my shot in the final was in the running stage, 40-50 Mi Mingming’s data has a larger deviation than the semi-final data, and compared with my current data collected by the championship system, it is even more offset by 10~5.”

"This shows that the stability of my paving the ground is still lacking."

"And this problem can actually be optimized with a new technology concept."

new technology?
Hearing this, everyone became excited, and looked at God Su one after another, little stars almost popping out of their eyes.

Even Randy was dumbfounded.

It was obviously a summary analysis meeting, but why did it turn into a direct conclusion and introduction of new technologies?

You do it.

We will be coaches in the team in the future, and the pressure will be very high, and it will be difficult to handle.

Su Shen inserted the PPT he had made, and after the computer started to read the USB flash drive, he said, "This is it."

"In the future winter training, we will allow a group of qualified people to start training to enhance their ability to run and pick up ground on the way."

And at this time, on the big screen, there were a few big characters written——

Optimized version of "credit card" landing technology.

PS: This type of chapter is not easy to write, hahahaha, the writing is so slow, but I believe that in this way, the sense of reality can explode.And taking the opportunity to improve and launch new technologies is also a matter of course~~~~
I hope everyone will support and help Xiaozi to read the paper late at night~~~o(╥﹏╥)o~~~
(End of this chapter)