"Niu Guohong, after yesterday's observation, I found that your main problem is that the back pedal force is too great!" Li Dai spoke out about Niu Guohong's shortcomings. Pen ~ fun ~ pavilion www.biquge.info

Niu Guohong's eyes narrowed slightly, and the color of mockery flashed.

"Too much back kick force?" Niu Guohong had a proud expression on his face, and he said: "Coach Li, shouldn't the strength of the back pedal be an advantage?" The more power you have on the back pedal, the more power you have, and the faster the athlete will get. Coaches generally dislike that an athlete's back press is too strong, and it's the first time I've heard of a coach who dislikes an athlete's back press too much. Coach Li, how do you say that the advantages are the disadvantages! ”

The smile on Li Dai's face did not change, yesterday, when he used the detector to detect Niu Guohong, when he saw "too much back pedal force" in the column of disadvantages, he also thought that the detector had reversed the advantages and disadvantages, and it was said that the high back pedal force should be an advantage.

But later, Li Dai combined the knowledge he learned in the national team and after careful analysis, he finally understood that the excessive power of the back kick is indeed a technical defect for the sprinting technique that Niu Guohong is now using.

Li Dai didn't panic, and explained: "In the traditional sprinting technique, the knee joint is fully straightened when the supporting leg is pushed back, which requires the athlete to have a better back pedal technique, and the athlete is required to improve the back pedal strength and lower limb ability. That's what you've been practicing before, right? ”

Niu Guohong nodded: "When I was in junior high school and high school, I did use this sprinting technique, but after entering Tsinghua University, I have switched to swing running technology." In the national team, swing running should be the most conventional sprinting technique, right? ”

"The national team is really using the technique of swing running. However, with the swing running technique, the athlete does not need to push the knee fully when exercising at high speeds. Li Dai said.

"My knee is not fully straightened." Niu Guohong immediately retorted.

"Don't worry, I'm not done yet. When you run, although the knee joint is not fully straightened, but your back kick action uses too much force, your swing running technique is not perfect, you bend your knees through subjective consciousness to push the ground, the result is that the forward swing conversion after kicking the ground is relatively slow, that is, the support time is extended, the extension of the support time, for the impact of speed, I don't need to introduce more, right? ”

In sprinting, the foot support on the ground means that the body and the ground are in contact, as long as the object is in contact, it will inevitably produce friction, so the longer the support time, the longer the time affected by friction, the greater the resistance to advance, so the sprinter will reduce the support time as much as possible, which is equivalent to reducing friction.

Of course, the support time cannot be zero, and if the support time is "zero", it is equivalent to flying, so the sprint race should be changed to a flying race.

Niu Guohong, as a first-class sprinter, of course knows these truths, and as a scholar, Niu Guohong's thinking ability is also very strong.

However, Niu Guohong still doesn't think that his running style needs to be improved, he is a proud person, he has been treated by his peers since he was a child, and his self-esteem makes him unwilling to admit that he is wrong.

"There is some truth in what you said, if I push too hard, it will indeed be longer to support the time, which will lose some of the speed, but don't forget that the power of the back pedal is great, and it will also bring more power, which will increase the speed. And this increase in speed has been able to compensate for the speed loss caused by the extension of the support time. Niu Guohong said calmly, he knew that if he wanted to prove that he was right, he had to be calm and reasonable now.

"I really can't prove whether it's more power from the back pedal or more resistance from the longer support time. But what I'm sure of is that your technology has to be improved. Li Dai spread his hands.

"Why? If the power of the back pedal is greater than the resistance of the extended support time, wouldn't I run slower if I changed this technique? Niu Guohong said with a rebellious face.

Li Dai was not in a hurry, and then explained: "Of course I have my basis, do you often encounter the situation that the upper and lower legs are not tightly folded, and the center of gravity of the body is low? ”

"How do you know?" Niu Guohong's face changed.

"The reason is that your back push is too strong, which not only prolongs the support time, but also does not allow the muscles to be relaxed in time, which then affects the transition and connection speed of the hip flexion forward swing action, and even when the forward swing action, occasionally the upper and lower legs are not tightly folded and the body center of gravity is low. This is obviously inconsistent with the characteristics of high center of gravity thigh forward swing, rapid downward pressure change, and tight folding of the upper and lower legs in the swing running technique! Li Dai opened his mouth to explain

A shocked expression finally appeared on Niu Guohong's face, these shortcomings that Li Dai said were all unknown to him before, and no one had ever told him.

Theoretically speaking, what Li Dai said is absolutely true, but just a set of theories that sound perfect cannot convince Niu Guohong, and what really impresses Niu Guohong is the two drawbacks that Li Dai said in the end.

The upper and lower legs are not tightly folded and the center of gravity of the body is low, these are the two disadvantages mentioned by Li Dai, and Niu Guohong has indeed encountered this situation in his daily training.

These two drawbacks do not occur 100%, but occur occasionally, especially when the training volume is relatively large, and the number of occurrences will increase. Niu Guohong originally thought that it was just that his body was too tired and his completion of technical movements had decreased, so these two situations occurred.

But now it seems that the real fact is exactly what Li Dai said, because the back press force is too strong, prolonging the support time, and at the same time can not make the muscles relax in time, which then affects the transition and connection speed of the hip flexion forward swing action.

At this moment, Niu Guohong knew that what Li Dai said was right, and the back pedal was too strong, which was indeed his defect!

"I'm convinced! Thoroughly convinced. Niu Guohong secretly said in his heart, he instantly lowered his posture, and at the same time said with a sincere face: "Coach Li, please help me improve a shortcoming!" ”

Li Dai smiled and nodded, and got Niu Guohong, the first brother of the Tsinghua sprint team, and he also established the authority of the coach in the Tsinghua sprint team.

He handed an A4 piece of paper to Niu Guohong: "This is the training plan I arranged for you, take a look!" ”

"Thank you, Coach Li, I will definitely follow your plan and practice seriously." Niu Guohong took the training plan with both hands, and immediately expressed his position without even looking at it.

"Okay, I'll personally instruct you on the essentials of technical movements in a moment." Li Dai smiled on the line, Niu Guohong, as the captain, has been tamed, so he will no longer be hindered in taking charge of the sprint team of Tsinghua University.

At this time, Li Dai couldn't help but glance at Yang Sijie, who was at the end of the line.

"There is one Yang Sijie left, this A-level talent guy, he is the most troublesome one!"