PMSP (Pre Motion Silent Period)
Besides APA, there is another term that is important to understand puncher-type mechanics: PMSP, the abbreviation for Pre-Motion Silent Period.
PMSP occurs at the same timing as APA, and it means unconscious muscle relaxation that occurs just before an intentional (voluntary) muscle contraction. Likewise APA, PMSP occurs only when we try to generate large power quickly and suddenly from a static position.
Figure22: An example of PMSP experiment and its electromyogram
For example when you try to jump as quickly as you can directly from a slightly squatting position like figure23, the relevant muscles fall into PMSP right after you decided to jump in your brain. Right after the PMSP, those muscles generate explosive power to jump.
In this case, interestingly, a squat move occurs automatically by the body weight of the subject, thanks to PMSP.
Figure23: Vertical-jump experiment for PMSP (movie1-16)
PMSP is definitely different from intentional relaxation. In other words, I didn't say that you should relax before you move quickly like tennis players do (see figure24). Actually that is the most common misunderstanding about PMSP, though above saying itself is right.
Figure24: This is intentional relaxation, but not PMSP.
PMSP occurs unconsciously when we try to generate large power suddenly and quickly. In a sense, it is quite the opposite phenomenon of intentional relaxation because it occurs when we try to generate power.
To understand PMSP more easily, imagine doing arm wrestling and a sprint race. When you start to move right after hearing the starting signal, there should be a split second of time lag before your body starts moving actually. PMSP occurs in that split second of time lag and so does APA.
Figure25: PMSP in arm wrestling
In the case of dodgeball experiment (p1-13), when lower body generates the power due to APA, upper body falls into PMSP.
As a result of the lower body generating power and the upper body relaxing, the core muscles are stretched enough. Because of that reason, APA and PMSP are essential factors to make a separation in puncher-type mechanics.
Figure26: Work of APA and PMSP in dodgeball experiment
By this mechanism, we can generate large power without any intentional preparative motion such as back swing, weight transfer, and separation. I refer this effect as "backswing effect'" — it stretches muscles that are used in forward swing. The backswing effect is indispensable in puncher-type mechanics.
Figure27: Work of APA and PMSP in puncher-type mechanics
Lean more ~ Wall push experiment for APA ~
This is an experiment for APA and the resulting "backswing effect". Push a wall with your full power from a static position like figure28. In this experiment, your lower body should generate power due to APA just before your arms push the wall.
As a result, your whole body should move toward the wall with your elbows left behind your back like a prone position of push-up training (figure29), which stretches the upper body muscles to push the wall (see figure30). This is the very "backswing effect", and thanks to it, you can push the wall strongly without any preparative motion. In addition, PMSP also works effectively in the "backswing" as relaxed muscles can be stretched well. This mechanism works in hitting mechanics too.
Figure28: Wall push experiment (movie1-17)
Figure29 Figure30
PMSP and APA have two common factors like the following. Understanding PMSP and APA is very important for puncher-type hitters as their hitting mechanics depends on PMSP and APA.
(1) Both of them occur unconsciously when you try to generate large power quickly and suddenly from a static position.
(2) Both of them occur at the same timing: right after you decide to generate power and just before your muscles actually generate power for the motion you intend to do.
While these two functions (PMSP & APA) cause a split second of delay in the start of hitting mechanics, we can generate large power without any preparative motions, thanks to them.
By the way, these two functions might work effectively in the primitive life of our ancestors. For example, when they fended off sudden attacks to their feet from dangerous creatures like snakes, they would jump up in the same way as that of vertical-jump experiment (figure23).
That is because in those cases, they cannot afford to think like, "let me squat down to stretch my muscles before jumping up." However, muscles cannot contract strongly without being stretched just before the contraction. Backswing effect due to PMSP and APA can be a solution to such a contradictory situation in which there is a need to generate large power as quickly as possible.
Besides APA, there is another term that is important to understand puncher-type mechanics: PMSP, the abbreviation for Pre-Motion Silent Period.
PMSP occurs at the same timing as APA, and it means unconscious muscle relaxation that occurs just before an intentional (voluntary) muscle contraction. Likewise APA, PMSP occurs only when we try to generate large power quickly and suddenly from a static position.
Figure22: An example of PMSP experiment and its electromyogram
For example when you try to jump as quickly as you can directly from a slightly squatting position like figure23, the relevant muscles fall into PMSP right after you decided to jump in your brain. Right after the PMSP, those muscles generate explosive power to jump.
In this case, interestingly, a squat move occurs automatically by the body weight of the subject, thanks to PMSP.
Figure23: Vertical-jump experiment for PMSP (movie1-16)
PMSP is definitely different from intentional relaxation. In other words, I didn't say that you should relax before you move quickly like tennis players do (see figure24). Actually that is the most common misunderstanding about PMSP, though above saying itself is right.
Figure24: This is intentional relaxation, but not PMSP.
PMSP occurs unconsciously when we try to generate large power suddenly and quickly. In a sense, it is quite the opposite phenomenon of intentional relaxation because it occurs when we try to generate power.
To understand PMSP more easily, imagine doing arm wrestling and a sprint race. When you start to move right after hearing the starting signal, there should be a split second of time lag before your body starts moving actually. PMSP occurs in that split second of time lag and so does APA.
Figure25: PMSP in arm wrestling
In the case of dodgeball experiment (p1-13), when lower body generates the power due to APA, upper body falls into PMSP.
As a result of the lower body generating power and the upper body relaxing, the core muscles are stretched enough. Because of that reason, APA and PMSP are essential factors to make a separation in puncher-type mechanics.
Figure26: Work of APA and PMSP in dodgeball experiment
By this mechanism, we can generate large power without any intentional preparative motion such as back swing, weight transfer, and separation. I refer this effect as "backswing effect'" — it stretches muscles that are used in forward swing. The backswing effect is indispensable in puncher-type mechanics.
Figure27: Work of APA and PMSP in puncher-type mechanics
Lean more ~ Wall push experiment for APA ~
This is an experiment for APA and the resulting "backswing effect". Push a wall with your full power from a static position like figure28. In this experiment, your lower body should generate power due to APA just before your arms push the wall.
As a result, your whole body should move toward the wall with your elbows left behind your back like a prone position of push-up training (figure29), which stretches the upper body muscles to push the wall (see figure30). This is the very "backswing effect", and thanks to it, you can push the wall strongly without any preparative motion. In addition, PMSP also works effectively in the "backswing" as relaxed muscles can be stretched well. This mechanism works in hitting mechanics too.
Figure28: Wall push experiment (movie1-17)
Figure29 Figure30
PMSP and APA have two common factors like the following. Understanding PMSP and APA is very important for puncher-type hitters as their hitting mechanics depends on PMSP and APA.
(1) Both of them occur unconsciously when you try to generate large power quickly and suddenly from a static position.
(2) Both of them occur at the same timing: right after you decide to generate power and just before your muscles actually generate power for the motion you intend to do.
While these two functions (PMSP & APA) cause a split second of delay in the start of hitting mechanics, we can generate large power without any preparative motions, thanks to them.
By the way, these two functions might work effectively in the primitive life of our ancestors. For example, when they fended off sudden attacks to their feet from dangerous creatures like snakes, they would jump up in the same way as that of vertical-jump experiment (figure23).
That is because in those cases, they cannot afford to think like, "let me squat down to stretch my muscles before jumping up." However, muscles cannot contract strongly without being stretched just before the contraction. Backswing effect due to PMSP and APA can be a solution to such a contradictory situation in which there is a need to generate large power as quickly as possible.
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