The Su God of the Reopening of the Sports Arena

Chapter 2499 is quite something! Customized Physiological Talent Technology

The core value of the twelve-fascial chain theory lies in...

The human musculoskeletal system is viewed as a continuous, rigid force transmission network, rather than a simple superposition of isolated muscle groups.

No one had ever perfectly mastered this theoretical system before, and Su Shen had only tried it one step at a time.

Of course, as the one who restarted the project and possessed extremely rich theoretical knowledge, he was the most qualified person to do so.

After the super-initiative burst, the next step is to accelerate along an ultra-low center of gravity trajectory, similar to that of Moscow.

But Moscow also said that if it weren't for the rain, it would have brought about a smoother and more unique experience.

The difference in ground feedback is due to changes in reaction forces caused by the softening of the runway due to rain.

It's very difficult to do this on a sunny day.

but.

This problem has existed for the past two years.

Su Shen has already won her over.

This should be done on non-rainy days.

Su Shen's approach was—

In the ultra-low center of gravity technology of the 10-30 meter acceleration zone.

The flexion-arm initiation force of the double forearm line and the steady-state support of the rear chain constitute the core myofascial mechanical basis for the implementation of the technique.

The synergistic effect of the two directly determines the acceleration efficiency and trajectory stability under ultra-low center of gravity.

It is especially suitable for high adhesion coefficient environments on dry tracks in non-rainy weather.

Double forearm line flexion start.

The positive feedback between the initial acceleration and force transmission.

From the perspective of fascial biomechanics.

When an athlete starts by bending their arm, the forearm flexor fascia is actively tightened, and the tension is transmitted to the palmar aponeurosis through the carpal tunnel fascia. When the palm swings to the front of the body, the palmar aponeurosis and the plantar fascia form an implicit mechanical linkage.

This linkage is not a direct physical connection, but is achieved through the cross-symmetric reflection mechanism of human movement.

In other words, the pulling force generated by the flexion and swing of the forearms will be transmitted to the opposite lower limb through the trunk fascia, stimulating the push-off muscles of the ipsilateral lower limb to enter the contraction preparation state in advance.

This shortens the delay time of lower limb exertion.

In the initial stage of the 10-30 meter acceleration zone, and in the 10-15 meter range, this double forearm line power generation mode with bent arm start can convert the energy of upper limb swing into the pre-starting power of lower limb start.

Achieve a rapid increase in startup speed.

This provides a speed basis for establishing an ultra-low center of gravity attitude in the future.

More importantly, the flexion of the forearm lines can regulate the tension of the core muscles through the tension feedback of the fascial chain. When the fascia of the forearm lines is in a stretched state, its tension signal is transmitted to the central nervous system through proprioceptors, triggering the synchronous tightening of the core fascia, making the trunk a rigid "force transmission platform".

Avoid energy loss at the torso due to the force of the lower limbs pushing off the ground.

This feedback mechanism works even more effectively in non-rainy weather conditions.

The high adhesion coefficient of a dry track results in a higher peak output of the lower limb push-off force. If the trunk fascia is in a relaxed state, it is very easy to cause the interruption or deviation of force transmission.

The double forearm line's flexion-arm initiation can ensure tension matching between the core fascia and the lower limb fascia through tension feedback.

To achieve seamless connection of force transmission.

Bang bang bang bang bang.

The moment the body passed the 10-meter marker line.

Su Shen's tense posture during the initial stage has not yet relaxed.

Take advantage of the momentum to accelerate into an ultra-low center of gravity.

This is not a deliberate squat, but a natural posture where the fascial chains and muscle groups work together.

Every dynamic detail is precisely aimed at maximizing horizontal propulsion.

The camera focuses on his torso and lower limbs, and the vertical adjustment of his center of gravity is clearly discernible in motion.

The hip joint maintains a flexion angle of 45°-50° throughout, and the acute angle of 30°-35° formed between the torso and the track remains completely still, as if being pulled forward by invisible force lines.

When the knee is bent to the 120°-130° range of force exertion, the quadriceps on the front of the thigh bulges like cast iron, yet there is no trembling. Each flexion and extension carries the rigidity of fascial transmission.

With the ankle joint in a 15°-20° plantar flexion position, the entire foot firmly "grips" into the dry track. The moment the sole of the foot contacts the ground, you can see the slight deformation of the spikes embedded in the track particles, but there is no sign of slipping.

Compared to the initial stage, the center of gravity is lowered by 15%-20% at this point, but the body does not feel heavy and sluggish. Instead, it feels like an arrow flying close to the ground, accelerating forward with inertia.

The hip joint remains in a stable flexed position at all times.

The torso forms a stable tilt angle with the track, and this angle is not maintained by passive muscle support.

Rather, it is the result of continuous tension feedback from the posterior fascia.

That's right, it's the backchain. Because this part starts up too quickly, when entering the acceleration zone, without the support of the backchain...

If you press so low, you're bound to crash.

The posterior fascia extends from the posterior side of the plantar fascia to the erector spinae fascia. During the forward leaning process, the fascia is moderately stretched, and the resulting elastic recoil force counteracts the torque of excessive forward leaning of the trunk.

Avoid situations where the upper body sways or the center of gravity suddenly drops.

The knee joint maintains a stable flexion range, and the quadriceps femoris muscle on the front of the thigh is in a state of continuous isometric contraction and concentric contraction, which stores sufficient elastic potential energy for each push-off movement.

The ankle joint maintains a moderate plantar flexion, the entire foot fits snugly against the track surface, the studs and track pimples have a uniform engagement depth, there is no excessive force on the forefoot due to a high center of gravity, nor is there heel dragging caused by a low center of gravity.

This allows Su Shen's entire lower limb joints to move in unison, keeping his center of gravity stably below the hip joint, compared to the center of gravity height of traditional acceleration techniques.

This posture effectively shortens the body's swing radius, improves the flexibility of gait frequency control, and increases the contraction amplitude of the lower limb muscle groups.

It provides more space for pushing off the ground and generating power.

In terms of proactive adjustment of the center of gravity in the horizontal direction.

Su Shen's body center of gravity projection point is always located in the area in front of the supporting foot contact point, forming a stable "center of gravity ahead" dynamic balance state.

Achieving this state depends on the continuous tightening of the core muscles and the precise timing matching of the lower limbs pushing off the ground.

The moment the supporting foot completes its contact with the ground and cushions the impact, the transverse abdominis and erector spinae muscles of the core muscle group contract synchronously, fixing the torso into a rigid whole and preventing excessive forward leaning of the upper body due to the center of gravity being too far forward.

Then, the lower limb muscles exert force, and the horizontal propulsive force generated by pushing off the ground propels the body's center of gravity forward. This forward shift of the center of gravity further stimulates the proprioceptors, triggering the next leg lift and push-off action, forming a positive cycle of "forward shift of center of gravity - force propulsion - forward shift of center of gravity again".

During the initial acceleration phase of 10-15 meters, Suarez's center of gravity shifted forward by a relatively small amount to ensure stability of his posture.

Entering the mid-acceleration phase of 15-30 meters, as speed increases, the center of gravity advances slightly more, utilizing the component of gravity to assist propulsion and reducing the force load on the lower limb muscles.

Throughout the process, Su Shen's horizontal movement of his center of gravity was smooth, without any sudden forward surges or pauses.

Instead, it is well-suited to the high adhesion coefficient of dry tracks.

Ensure that the propulsive force generated by each push-off is efficiently converted into forward speed.

The dynamic performance of lateral center of gravity stability control is reflected in the fact that Su Shen's body central axis always remains consistent with the movement trajectory, without any obvious left or right deviation.

During acceleration, the fascia maintains moderate tension, limiting excessive internal or external rotation of the hip joint and preventing lateral sliding when the supporting foot touches the ground.

At the same time, the oblique abdominal muscles of the core muscle group contract in synergy, effectively restraining the lateral sway of the torso. Under the high grip conditions of a dry track, Su Shen does not need to deliberately adjust his body posture to maintain lateral stability, and can focus more attention on the control of force in the forward and backward directions. Therefore, he can boldly maintain an ultra-low center of gravity posture, further improving acceleration efficiency.

Observe from the moving images.

Su Shenqi kept his shoulders and hips parallel at all times.

The lateral amplitude of the upper limb swing is extremely small.

It is completely consistent with the direction of the lower limbs pushing off the ground.

This has created a closed-loop technology system of "coordinated upper and lower limb exertion - lateral stability - linear acceleration".

The dynamic details of lower limb power generation are mainly reflected in the connection between the two phases of pushing off the ground and lifting the leg.

During the push-off phase, Su Shen adopts a full-foot strike technique, with extremely short cushioning time at the moment of contact, maximizing the contact area between the plantar fascia and the track surface. The ground reaction force is quickly transmitted upward through the plantar fascia, and then through the triceps surae fascia and quadriceps fascia to the core area.

In an ultra-low center of gravity posture, the distance between the origin and insertion points of quadriceps contraction is shortened, the contraction speed is accelerated, and the force efficiency is significantly improved.

The activation level of the gluteus maximus is increased simultaneously, providing additional power during hip extension and effectively increasing stride length.

The force exerted during the entire push-off motion is highly consistent with the direction of body movement, with a very low vertical component, thus avoiding speed waste caused by energy loss in the vertical direction.

In particular, the leg-raising phase of the movement exhibits a clear characteristic of "low leg raising and quick transition".

The leg lift height is significantly lower than that of traditional acceleration techniques, the knee joint bends more, and the angle between the lower leg and the ground remains within a small range.

The advantage of this movement pattern is that it shortens the swing radius of the leg lift, reduces the energy consumption during the leg lift phase, and keeps the lower limb muscles under moderate tension throughout the leg lift process, thus reserving elastic potential energy for the next push-off action.

In dry track conditions, low leg lifts do not increase the risk of slipping due to wet ground; on the contrary, they can increase stride frequency by speeding up the transition between leg lift and push-off.

From a dynamic perspective, the start of the leg-lifting motion and the end of the push-off motion are almost simultaneous. The moment the supporting leg pushes off the ground, the knee joint of the swinging leg immediately bends, the lower leg swings forward quickly, and the foot lands forward and downward in an active posture.

The entire gait cycle was smoothly connected, without any obvious pauses or sluggishness.

In addition, there is the coordinated action of the core and upper limbs.

In dynamic footage, this is manifested as the rigid stability of the torso and the height synchronization of the upper limb swing.

After entering the 10-30 meter acceleration zone, Su Shen's core muscles remained highly activated. The rectus abdominis, transverse abdominis, and erector spinae muscles contracted in synergy, fixing the torso into a rigid power platform. This ensured that the propulsive force generated by the lower limbs pushing off the ground could be efficiently transmitted to the whole body through the core muscles, avoiding force transmission loss caused by torso swaying.

At the same time, the continuous tightening of the core muscles provides a stable fulcrum for the upper limb swing, making the frequency of the upper limb swing completely consistent with the frequency of the lower limb stride.

The dynamic characteristics of upper limb swing are "bent arm swing, small amplitude and high frequency", with the elbow joint always maintaining a stable flexed state, and the fascia of both forearms in a continuous stretch-contraction cycle.

During the swing, the direction of force exerted by Su Shen's upper limbs is completely consistent with the direction of body movement. When swinging forward, the flexor fascia of the forearm tightens, and when swinging backward, the extensor fascia of the forearm exerts force. The resulting tension is transmitted to the lower limbs through the trunk fascia, forming a positive feedback to the lower limbs' push-off action.

Furthermore, because the upper limbs swing with a small amplitude, the lateral sway is almost negligible. This feature further enhances the body's lateral stability, thereby ensuring the linearity of the acceleration trajectory.

Observing the dynamic footage, the rhythm of the upper limb swing is highly synchronized with the rhythm of the lower limb pushing off the ground, and the forward swing motion is synchronized with the landing motion of the swinging leg.

The backswing motion is synchronized with the pushing-off motion of the supporting leg, forming a coordinated force exertion pattern of "upper limbs leading lower limbs and lower limbs promoting upper limbs", resulting in a highly coordinated and fluid overall movement.

how is this possible.

How could it be compressed so low?
These Americans have no idea how wide their eyes are.

In their understanding, humans maintain this state of motion, especially under such a high-saturation start-up state...

You can't possibly lower it that low and still maintain your balance.

Just kidding.

You must be joking.

Are you Superman?

Their understanding was challenged.

A group of proud Americans believed that with a lightning-fast device infused with their advanced knowledge system, they would be invincible.

Defeat everyone.

And then here.

Su Shen hit him hard first.

Of course, they are right about one thing...

That is when humans are faced with images that are beyond their cognitive system.

Subconsciously, people would think this is superhuman behavior.

Many modern sports systems, scientific systems, and cognitive systems, if placed in ancient times...

That would be no different from Superman.

Just like 100 years ago, when the Olympics first started, people certainly didn't know that human sprinting could have evolved to the present day.

It can possess so many technical theories.

You can even run like this.

Therefore, if you put athletes from this era into the past, it would be a game-changer.

In their eyes, he is a superman.

And the facts.

This is just your theoretical understanding; you haven't reached that level.

The event in front of you is simply beyond your comprehension.

But if you understand these aspects, you will be just like Su Shen.

You'll end up like Randy and the others next to you.

We will look at this matter from a more scientific perspective.

Of course, if these people were so shocked, Bolt was no different.

However, he was an athlete competing on the spot.

There was no time to be distracted, and after the setbacks of the previous two major competitions.

He already knew that all sorts of tricks would be used against Su Shen.

It's not the first or second time, is it?
You are indeed very strong.

You are indeed improving every time.

But I...

Usain Bolt.

Isn't that the case as well?

Bolt's start this time also marked the pinnacle of his career.

Therefore, he didn't waste words with Su Shen.

They also began to showcase their improved results.

Yes.

Bolt didn't panic.

Otherwise, it would be a disservice to the results of his hard work and self-discipline over the past few years.

Perhaps for others, self-discipline may not be so easy, but it's not that difficult.

Self-discipline is extremely difficult for Bolt.

It's like dancing on a knife's edge.

I don't go to bars to pick up girls or play games.

This is really a killer for him.

To win, they've endured so much for the past few years. What kind of person lives like that?

That was the only inner motivation that kept me going.

Isn't it just about defeating this guy next to me?
Therefore, Bolt also showed his true skills here.

His speed increased after entering the acceleration zone.

It also suddenly started to speed up.

What is the core biomechanical basis of the flexed arm start?

The answer from the Amelica Labs is—customized torque control and power chain transmission optimization based on the extra height and wingspan.

The core technical goal of the starting phase of a sprint is to transform the body from a static state to forward acceleration in a very short time. Torque regulation and efficient power chain transmission are the two core biomechanical pillars for achieving this goal.

For Usain Bolt, who is 1.96 meters tall and has a wingspan far exceeding that of other sprinters in his class, the bent-arm start technique is not a mere replication of the posture of ordinary athletes, but a customized technological innovation based on his unique body shape.

That's how it's done in the lab here in America.

They're not a sports lab in Jamaica; they're just trying to scam funding.

Although they also fraudulently obtain funding here, they are still able to produce results and achievements while doing so.

After their research and analysis, they concluded that—

Bolt's exceptionally long wingspan, combined with the leverage length advantage of his upper limbs and the angle of his bent-arm posture, should establish a force transmission path that is completely different from that of ordinary athletes from the moment he pushes off the starting blocks.

It provides dedicated mechanical support for the hip thrust movement after a 0-10 meter start into the acceleration zone.

From the perspective of the nature of torque, the mechanical efficiency of the arm, as a lever of the human upper limb, is determined by the lever length and the moment of inertia.

During the starting phase, the arm swing is a rotational motion around the shoulder joint, and the moment of inertia is positively correlated with the square of the radius of rotation.

However, Bolt's wingspan far exceeds that of ordinary sprinters. While the wingspan of most male sprinters is close to their height, Bolt's wingspan is much longer than his height.

This means that in a straight-arm position, his arm rotation radius r will be much larger than that of other athletes, the rotational inertia will increase exponentially, and the muscle contraction force required to drive the arm swing will be more than 1.5 times that of ordinary athletes.

The core value of the bent-arm posture is precisely the "dimensional reduction adaptation" for his super long arm span - when the elbow bend angle is locked at about 90°, the arm's rotation radius is greatly shortened. Compared with the straight-arm posture, the rotation radius is reduced by up to 40%. Combined with the advantage of his arm span length, the reduction effect of rotational inertia is far greater than that of ordinary athletes.

The direct effect of this change is that Bolt no longer needs to expend extra energy to drive his super-long arms; he only needs less muscle contraction force to drive his arms to complete high-frequency, high-amplitude swings.

The saving of muscle contraction force means that more energy can be precisely allocated to the extension and hip thrust movements of the lower limbs.

This is precisely the key energy distribution logic in the 0-30 meter acceleration zone, especially the 0-10 meter start-up and acceleration phase.

More importantly.

Bolt's exceptionally long wingspan combined with his bent-arm posture.

A composite mechanical model of "long lever-short radius" was constructed, which is beyond the reach of ordinary athletes. The bending arm swing of ordinary athletes is more about reducing energy consumption by shortening the radius, while Bolt's bending arm swing retains the traction advantage of the long lever of the upper limb while "shortening the radius".

When his bent arm completes the forward swing, the long lever formed by his extra-long forearm amplifies the contractile force of the shoulder muscles, transforming it into a stronger forward traction force.

The 90° bending angle avoids the problem of excessive rotational inertia caused by a long lever. This composite mechanical model makes his upper limb swing no longer a simple balancing action, but a "power source" that drives hip thrust—a mechanical advantage that athletes of average height and wingspan cannot replicate even if they imitate the same bent arm angle.

Black people naturally have longer arms, and Bolt's arms are more than 20 centimeters longer than his height.

It's enough to make Yao Ming cry.

There are even reports claiming that his arm length, from the seventh vertebra to the wrist, reaches an absurd 99 centimeters.

This is a physiological advantage that cannot be replicated.

If you don't have the talent, you can't do it no matter what you do.

This means that the physiological differences between individuals lead to different movement patterns.

and so.

Analyzing from the perspective of power chain transmission.

The kinetic chain of human sprinting follows a transmission path of "core drive - upper and lower limb coordination".

The kinetic chain at the start begins with the ground reaction force of the lower limbs pushing off the starting blocks, and is transmitted through the hips, core, and shoulders to the upper limbs, forming a closed-loop force transmission system.

For Usain Bolt, who is 1.96 meters tall, his center of gravity is much higher than that of ordinary athletes. The core challenge in the starting phase is how to efficiently transfer the ground reaction force to the hips while maintaining a stable center of gravity, so as to drive the hip thrust.

His bent-arm posture provides a customized solution to this problem—forming a rigid fulcrum at the shoulder joint, rather than the flexible swinging fulcrum of the straight-arm posture.

For ordinary athletes, the shoulder fulcrum is mainly used to receive the force transmitted from the lower limbs, while Bolt's rigid shoulder fulcrum, due to his extremely long wingspan, forms a "force reflection amplifier".

When the ground reaction force generated by the lower limbs pushing off the starting blocks is transmitted upward to the core, the rigid fulcrum of the shoulder brought by the bent arm can effectively prevent the force from being ineffectively dispersed to the upper limbs; at the same time, the lever structure formed by the ultra-long arm span will "reflect" this part of the force back to the hip.

And through the leverage effect.

Increase the torque of the hip thrust movement.

For ordinary athletes, the torque of hip thrust mainly depends on the contraction of the lower limb muscles, while Bolt obtains an additional torque boost through the long lever reflex of the upper limbs!
This is the core reason why he was able to complete the hip thrust with agility far exceeding his height expectations during the 0-10 meter start phase.

Specifically, after the 0-10 meter start phase, the athlete's center of gravity transitions from "forward support" to "forward propulsion," at which point the hip thrust requires a forward traction force.

Bolt's bent-arm swing, with his elbow at a bend of about 90° during the forward swing, and his forearm almost parallel to the ground, is precisely the angle that allows the swing direction of his extra-long forearm to be completely consistent with the direction of his body's forward movement.

When the arm swings forward, the contraction force of the shoulder muscles is transformed into a forward traction force through the rigid structure of the bent arm. Due to the leverage amplification effect of the extra-long forearm, the strength of this traction force far exceeds that of ordinary athletes.

The point of application of the pulling force is located in the upper part of the torso, which can drive the hip to move forward, forming an efficient hip delivery mode of "upper limb traction - hip following".

In contrast, when Bolt's arms are in a straight-arm swing, the direction of the swing is more of a lateral force perpendicular to the direction of the body's forward movement. This not only fails to generate effective hip traction, but also causes the center of gravity to shift to the left and right due to the excessive length of the arms, interfering with the stability of the hip thrust.

While a straight arm swing by an ordinary athlete does not result in such a significant shift in the center of gravity, it also fails to provide effective traction.

Furthermore, these American researchers are not to be underestimated.

The bent-arm start technique was also tailored to Bolt's body shape, optimizing the utilization efficiency of ground reaction force.

Based on Newton's third law, they concluded that the force of the lower limbs pushing off the starting blocks is equal in magnitude and opposite in direction to the ground reaction force.

At the start, the athlete's body leans forward at a large angle, and the ground reaction force has two components: vertically upward and horizontally forward.

The vertical component of force is used to counteract gravity and maintain body balance.

The horizontal force is the core driving force that propels the body forward.

For Usain Bolt, who is 1.96 meters tall, his body has a greater gravitational torque, requiring more vertical force to maintain balance...

This means that the proportion of the horizontal component force is easily compressed.

His bent-arm swing, through the coordinated swing of the upper and lower limbs, forms a "forward swing of the upper limbs - extension of the lower limbs" force couple system, which precisely makes up for this shortcoming.

The essence of a couple is a system of two parallel forces of equal magnitude, opposite direction and not collinear, which can cause a pure rotational effect on an object.

Bolt's arm swing and lower limb extension create a force couple that ordinary athletes cannot match.

First, the extra-long arm span results in a longer couple arm, and the magnitude of the couple moment is positively correlated with the length of the couple arm, thus its couple moment strength is higher.

Secondly, the bent-arm posture makes the direction of the force couple more precise, pointing directly in the direction of hip rotation.

During the acceleration phase at the start, this high-intensity couple acts directly on the hips, generating a forward rotational torque that amplifies the horizontal component of the ground reaction force.

The vertical component of the force originally used to maintain balance is also converted into horizontal power to drive the hip thrust, changing Bolt's hip thrust from "passive following" to "active driving".

However, the force couple system of ordinary athletes has a shorter arm span, a limited arm length, and insufficient torque strength, making it difficult to achieve efficient conversion of vertical force into horizontal force.

Therefore, the second point of Amelia's customized plan for Bolt was the core theoretical support for the flexed-arm start technique:

Based on the advantages of height and arm span, neuromuscular control and movement timing are coordinated and customized.

Usain Bolt's flexed-arm start technique significantly improves hip delivery efficiency in the 0-30 meter acceleration zone. Besides its customized biomechanical advantages, this is also deeply supported by neuromuscular control theory and the theory of movement timing coordination.

The application of these two theories is also based on his personalized adaptation to his exceptionally long height and wingspan.

For Bolt, the bent-arm posture is not only an optimization of the mechanical structure, but also a "calibrator" for neuromuscular control and movement timing coordination, allowing his physical advantages to be maximized at the starting stage.

The first is the neuromuscular control theory.

Long lever adaptation optimization requires proprioceptive enhancement and muscle preactivation.

The core of neuromuscular control is that the central nervous system receives positional information of muscles and joints through proprioceptors, and then regulates the timing and intensity of muscle contraction.

For tall athletes like Usain Bolt with long arms spans, the challenge of neuromuscular control lies in the precision of positional perception at the end of a long lever. The lever structure of an ultra-long arm and lower limb results in a longer signal transmission path for proprioceptors, leading to a higher probability of signal delay and distortion.

His current bent-arm starting posture shortens the signal transmission path of the proprioceptors by changing the angle of the arm joints, enhances the accuracy of signal input, and thus improves the precision of nerve control over the hip muscles.

As receptors for changes in muscle length, muscle spindles are highly sensitive to changes in muscle length. When Usain Bolt starts running, his arms are bent at approximately 90 degrees. At this point, the deltoid and biceps muscles in his shoulder are in a moderately tense initial state, and the sensitivity of the muscle spindles is activated to its optimal level.

More importantly, the bent-arm posture transforms his extra-long arms from a "suspended long lever" into a "folded short lever," precisely limiting the range of muscle spindle perception of changes in muscle length within the effective range.

In a straight-arm posture, the swing amplitude of an extra-long arm is large, and the muscle spindles need to sense a wider range of length changes, which can easily lead to signal saturation.

With the arm bent, the swing amplitude of the arm is controlled within the sensitive range of the muscle spindle, improving the accuracy of signal input by more than 30%. When the arm begins to swing, the muscle spindle can quickly and accurately sense changes in muscle length and transmit the signal to the central nervous system.

Based on this high-precision signal, the central nervous system synchronously regulates the contraction of the hip-sending core muscles such as the iliopsoas and gluteus maximus in the lower limbs.

This neural linkage of "upper limb swinging - lower limb hip thrust" is particularly evident after the 0-10 meter initiation phase.

Therefore, when Bolt completes the first forward swing of his bent arm, the precise signal input from the muscle spindle triggers a rapid contraction of the hip muscles, making the hip thrust and arm swing completely synchronized.

For ordinary athletes, the delay time of this neural linkage is usually around 0.05 seconds, but Bolt shortened the delay time to less than 0.02 seconds by optimizing the signal accuracy of the bent-arm posture, completely avoiding the hip lag caused by the delay of proprioceptive signals when starting with straight arms.

Furthermore, Bolt's exceptionally long wingspan allows for a wider "coverage" of this neural linkage—

The signal from upper limb swing can drive a wider range of hip muscle contraction, further enhancing the power output of the hip thrust.

At the same time, the bent-arm posture also optimizes the pre-activation effect of muscles for Bolt's body shape.

Muscle pre-activation refers to the process by which the central nervous system sends impulses to the muscle before it actively contracts, putting the muscle in a slightly activated state, thereby increasing the strength and speed of subsequent contractions.

For tall athletes, pre-activating the hip muscles is more difficult—as the core hub of the body, the hip needs to drive the movement of both the long lower and upper limbs simultaneously, requiring a wider range of pre-activated muscles and higher intensity.

Bolt's bent-arm start, during the preparatory phase on the starting blocks, involves bending his arms at an angle that pre-activates the upper limb muscles.

This pre-activation is transmitted to the muscle groups of the contralateral lower limb through the cross-activation effect of nerves, and the transmission range and intensity far exceed those of ordinary athletes.

Specifically, Amelica's researchers hope that when Bolt's right arm is pre-activated by bending, the hip flexors in his left lower limb will also be pre-activated simultaneously.

vice versa.

Their reasoning is that because Bolt has longer arms, the pre-activation range of his upper limb muscles is greater, and the cross-activation effect can cover more hip muscle fibers.

The cross-activation effect in ordinary athletes only covers about 60% of the hip muscles.

Bolt, on the other hand, can cover more than 80%.

This extensive pre-activation allows the hip muscles to have higher contractile potential energy before pushing off the starting blocks, enabling them to release energy more quickly after the 0-10 meter start phase, propelling the hips forward.

However, if Bolt adopts a straight-arm posture, the pre-activation range of his upper limb muscles will be greatly reduced, the intensity of the cross-activation effect will also decrease, and the contraction potential energy of the hip muscles will not reach the optimal state.

This is further combined with the theory of action sequence coordination.

This refers to the customized control of phase synchronization and energy complementarity of long lever movements of the upper and lower limbs.

The Amelika people.

I firmly believe in Bolt's current bent-arm start.

It's already the best in history.

It is a case of the student surpassing the teacher.

Their theory of action timing coordination suggests that the acceleration process in sprinting involves a high degree of coordination between the upper and lower limb movements in time and space. Only when the phases of the upper and lower limb movements are completely synchronized can the maximum utilization of energy be achieved.

For tall athletes like Bolt with long arms spans, the core challenge in coordinating movement timing is phase matching of long-lever movements.

With exceptionally long upper and lower limbs, the swing cycles are even longer, requiring more precise timing control to achieve accurate synchronization. His bent-arm start technique adjusts the timing and phase of the arm swing.

It achieves perfect synchronization of long lever movements of the upper and lower limbs, thus forming a complementary synergistic effect in the 0-30 meter acceleration zone.

You need to know that this is during the 0-10 meter start-up phase.

The athlete's main task is to push off the starting blocks and gradually raise their center of gravity from a low position.

At this moment, Bolt's arm swing frequency and lower limb extension frequency are in 1:1 phase synchronization—that is, when the lower limb completes one extension, the upper limb completes one arm swing.

The achievement of this synchronization depends entirely on the "compression" of the upper limb swing cycle by the bent-arm posture. In the straight-arm posture, his extra-long arm swing cycle is about 0.03 seconds longer than that of ordinary athletes, making it difficult to match with the lower limb push-off cycle.

In the bent-arm posture, the swing cycle of the arm is compressed to be completely consistent with the extension cycle of the lower limb, thus achieving precise phase synchronization.

This synchronicity ensures that the inertial force generated by Bolt's upper limb swing and the propulsive force generated by his lower limb extension coincide in time, forming a superimposed resultant force that acts directly on his hip.

More importantly.

Bolt's exceptionally long wingspan makes the combined force far stronger than that of ordinary athletes—the inertial force generated by the swing of the upper limbs is positively correlated with the mass of the arm and the swing speed.

Because his arm has a larger mass, swings faster, and has a higher inertial force.

The propulsive force generated by his lower limbs pushing off is also stronger due to his muscle mass advantage.

The combined force of the two can provide stronger forward momentum to the hip, making the starting speed of the hip thrust movement... naturally faster.

And when starting with a straight arm.

Bolt's arm swing cycle deviates from his lower limb extension cycle, resulting in the inability of the forces from his upper and lower limbs to effectively combine, and some energy is canceled out.

Even if ordinary athletes achieve phase synchronization, they cannot generate such a high-intensity combined force due to the disadvantages in arm mass and swing speed.

So you can see that after Bolt entered the 10-30 meter acceleration zone...

His arm swing angle will be slightly adjusted as his body's center of gravity rises.

The elbow flexion angle gradually increases from 90° to about 120°.

This angle adjustment is a customized adaptation to suit the spatial synergy of his extra-long arm span.

As the body's center of gravity shifts forward, the Amelica Lab requires that Bolt's hip thrust in the acceleration zone change from "small forward thrust" to "large forward thrust".

This requires upper limb swinging to provide a greater range of traction.

Increasing the elbow flexion angle can be done without increasing the moment of inertia.

Expand the range of motion of the upper limbs.

It precisely matches the amplitude changes of the hip thrust movement.

At this moment, Bolt's arm swing trajectory is completely consistent with the trajectory of his hip forward. The swing of his upper limbs is no longer a simple balancing action, but has become a "guide" for the hip thrust.

The forward swing of the bent arm drives the torso forward, and the torso drives the hips forward, forming a chain-guided system of "upper limb-torso-hip".

The advantage of this chain-guided system lies in the wider traction range of the long lever.

Bolt's extra-long forearms allow his torso to move forward a greater distance, thereby enabling his hips to complete a larger hip thrust.

The chain-guided system of ordinary athletes, due to their shorter arm span and limited traction range, makes it difficult for them to achieve the same level of hip thrust as Usain Bolt.

However, if Bolt adopts a straight-arm posture, although the range of arm swing is large, the moment of inertia is too high.

This would prevent the formation of an efficient chain of guidance.

Furthermore, Bolt's swing here also maximizes energy complementarity.

In other words, the energy saved by swinging the upper limbs is fully transferred to the hips through the chain-guided system to drive the hip thrusting motion.

The forward momentum generated by the hip thrust will, in turn, increase the swing speed of the upper limbs.

This creates an "energy cycle amplification" effect.

This complementary energy effect is unattainable for ordinary athletes, and it is also what enables Bolt to accelerate in the 0-30 meter acceleration zone.

The core reason for achieving ultra-high acceleration efficiency with its tall stature.

You can see that from the above.

Bolt's bent-arm start technique is a completely customized solution developed by Amelica based on his 1.96-meter height and super long wingspan.

It is not a simple posture adjustment, but a comprehensive adaptation from biomechanical torque regulation and kinetic chain transmission to neuromuscular control and movement timing coordination.

Whether you like Emilia or not.

You must also admit it.

This approach deeply integrates the advantages of body shape with technological theory.

At this stage, apart from the reopened Su Shen.

Only on Amelika's side.

Only then can it be achieved.

No wonder Bolt was so impressed after seeing Suarez unleash such a powerful burst of speed.

There is still a source of confidence.

Because of this aspect.

Customized improvement of physiological talents through iterative technological advancements.

It is designed entirely around the individual needs of the athlete.

This allows athletes to better utilize a particular technical theory.

On this point.

Emilia has done a really good job in this regard.

Whether it's track and field, basketball, or any other sport.

They are all among the best in the world.

It might even be number one.

Otherwise, Mills wouldn't have done this after he had exhausted all his options.

They pinned their hopes on Amelika.

It has to be said that it's quite something.

On the customization of sports.

Amika once said she was second to none, so who dares to claim to be first?

Bolt after his customized scientific attributes were enhanced.

It's true that you can run faster here.

Even Gatling guns, which excel at sprinting.

They are no match at all.

Even if Powell were watching from the sidelines, this kind of situation would be impressive.

They all felt they would definitely be suppressed.

And it's the kind of pressure that's really strong.

That's terrifying, those two lightning-level attacks.

Start from startup.

They had already entered a two-horse race mode.

outsider.

Even if you are a giant.

Even toes can't fit inside.

It's the kind of hole you can't even fit a toe in.

very good!

Yussane!
Show me the results of your two years of practice!
Mills saw Bolt's calm and collected confrontation and regained his composure.

He has been keeping track of the progress of his trip to the United States over the past two years.

therefore.

Regarding Bolt's progress.

He was more confident than anyone else.

Jamaica's lagging scientific research level was what held you back before.

just now.

There are no more burdens.

Yussane.

Fly with all your might!