重心 Zhòngxīn center of gravity

[windwalker099]

The recent discussions on 含胸拔背 (hán xiōng bá bèi), expanding the back and sinking the chest used in Taiji.

Thought it might be interesting to look at it from a different viewpoint, one of functionality over what some might feel are health concerns.
含胸拔背 (hán xiōng bá bèi), among many requirements, is used as part of a whole to create a synergistic effect using the body.

definitions provided by ChatGPT

Center of Mass (CM):
Definition: The center of mass is a point representing the mean position of the mass in a body or system. It is the weighted average location of all the mass in an object.

Center of Gravity (CG):
Definition: The center of gravity is the point at which the entire weight of a body or system is considered to act. It is the average location of the weight of an object.

General statement:

practices that maintain the center within the body



practices that use the center outside the body

Guang-ping Yang Tai Chi Standing

This practice is called "Zhan Zhuang (站桩)"


Methods are developed through the use of body shape and intention of use.
含胸拔背 (hán xiōng bá bèi) expanding the back and sinking the chest, part of the requirement for
"zhan zhuang" practice..In order to develop the awareness feeling of being able to move the center..

Thoughts ?

 

[isshinryuronin]

Center of Mass (CM):
Definition: The center of mass is a point representing the mean position of the mass in a body or system. It is the weighted average location of all the mass in an object.

Center of Gravity (CG):
Definition: The center of gravity is the point at which the entire weight of a body or system is considered to act. It is the average location of the weight of an object.

My understanding of physics is not sufficient for me to effectively differentiate between the two, but I will venture a comment on the part I underlined. I'll propose (for this example) that the "act" is delivering a strike:

\ l
.. \ --> l
... \ l
This represents an attacker moving against an opponent in this illustrative abstract example.

\ l
\ l
\l
Here, contact is made but not by the center. Forward action continues...

\ l
\l
l\
Here the center makes contact but the bottom's energy has been expended, and the top has not yet contributed.

While the center gets to the target, the "entire weight of a body or system" has not been delivered. Eventually the top will be, but the three parts will not have been delivered simultaneously with synergistic effect.

For maximum power a way must be employed so all the mass/weight/system's power is delivered together. It must be unified. Manipulation/control of the center (CG/CM?) is important as it is the unifier, allowing not just the center's potential force, but the entire body's force to be delivered as one. Chinkuchi is a part of this.

Mass is useless if it's not delivered, its power transferred to the target. In terms of attack, power generation and transfer are the main areas of concern and has many elements, mostly dependent on the center (tan-tien/tanden).

CM/CG in regard to balance have some different concerns but do come into play if balance becomes a casualty in the process of delivering power. Sanchin kata addresses this point, IMO.

 

[Wing Woo Gar]

My understanding of physics is not sufficient for me to effectively differentiate between the two, but I will venture a comment on the part I underlined. I'll propose (for this example) that the "act" is delivering a strike:

\ l.......This represents an attacker moving against an opponent in this illustrative abstract example.
\ --> l
\.................. l

\ l Here, contact is made \ l Here the center makes contact
\ l but not by the center. \l but the bottom's energy has been expended
\l Forward action continues... l\ and the top has not yet contributed.

While the center gets to the target, the "entire weight of a body or system" has not been delivered. Eventually the top will be, but the three parts will not have been delivered simultaneously with synergistic effect.

For maximum power a way must be employed so all the mass/weight/system's power is delivered together. It must be unified. Manipulation/control of the center (CG/CM?) is important as it is the unifier, allowing not just the center's potential force, but the entire body's force to be delivered as one. Chinkuchi is a part of this.

Mass is useless if it's not delivered, its power transferred to the target. In terms of attack, power generation and transfer are the main areas of concern and has many elements, mostly dependent on the center (tan-tien/tanden).

CM/CG in regard to balance have some different concerns but do come into play if balance becomes a casualty in the process of delivering power. Sanchin kata addresses this point, IMO.

Great post.

 

[isshinryuronin]

Great post.

In posting it the format of the diagrams went to hell. I hope the intent is still decipherable to others. I edited it but it did not help much.

 

[windwalker099]

CM/CG in regard to balance have some different concerns but do come into play if balance becomes a casualty in the process of delivering power. Sanchin kata addresses this point, IMO.

How does it address it ?
By what method ?


Thanks for the drawings, very cool

The thread is not really about right or wrong, proving or disproving. The intention is to help provide a lens through which to view things, with others offering their perspectives.

At the same time, addresses some practices that some had issues with, like 含胸拔背 (hán xiōng bá bèi), offering some thoughts on the functionality of the practice.

Key in this concept it can be changed to one's advantage, depending on the method.
Or it can be used independently of itself, through a method.

重心 Zhòngxīn center of gravity a key component among some practices..
Notably, those labeled as being internal.

 

[Kung Fu Wang]

"zhan zhuang" practice..In order to develop the awareness feeling of being able to move the center..

Thoughts ?

You can't learn "move your center" through "zhan zhuang" practice. You need to learn from footwork.

practices that maintain the center within the body

Why do you need to maintain the center within the body?

You need to:

- move your gravity center outside of your base.
- let the gravity to pull your body down.
- You then use footwork to regain your center/balance back.

All throwing techniques are built on top of this principle. Here are some training to achieve that.





In this video, at 0.01, when he sweeps his opponent's leg, his gravity center is outside of his base. The gravity pulls his body down. But he moves back his right leg to regain his balance.

Sometimes, it may need many steps to regain the balance back. I call this take down and take off.

 

[Kung Fu Wang]

In this video, he kicks out and move his gravity center to be outside of his base. The gravity pulls him down. He drops his kicking leg and punch his opponent's face.

Taiji system also uses this principle to use kick to set up punch.

 

[Kung Fu Wang]

This practice is called "Zhan Zhuang (站桩)"


Methods are developed through the use of body shape and intention of use.
含胸拔背 (hán xiōng bá bèi) expanding the back and sinking the chest, part of the requirement for
"zhan zhuang" practice..In order to develop the awareness feeling of being able to move the center..

Thoughts ?

Taiji requirement is not universal.

"含胸拔背 (hán xiōng bá bèi) expanding the back and sinking the chest" is not the only "zhan zhuang" practice. There are "zhan zhuang" practice that require expanding chest too.

 

[Wing Woo Gar]

In posting it the format of the diagrams went to hell. I hope the intent is still decipherable to others. I edited it but it did not help much.

More important was what you wrote. I got it.

 

[Wing Woo Gar]

Taiji requirement is not universal.

"含胸拔背 (hán xiōng bá bèi) expanding the back and sinking the chest" is not the only "zhan zhuang" practice. There are "zhan zhuang" practice that require expanding chest too.

View attachment 32377

View attachment 32376

If you fail to throw the opponent you will still be off balanced. I won’t sacrifice my root to attack my opponent. I am not saying you are doing anything wrong, it works for you. I am saying that it’s not how I do it, and that works for me.

 

[isshinryuronin]

How does it address it ?
By what method ?

Key features of Okinawan karate include what is termed in Chinese as baida, short-distance technique, and fajin, explosive power (as defined by I. Cohen), especially in Shorei/Naha styles. This may appear to be contradictory by many as their practice of producing power depends on building speed over distance, physically projecting their center toward the opponent (body movement). An example of this might be a full step forward and oi-tsuki punch ending in zen kutsu dachi deep stance. Much distance is covered by the fist, 5 or 6 feet (assisting in acceleration) and momentum (power) is generated - speed and mass over distance combine for a strong punch.

One of the things sanchin kata does is teach projecting power without moving your center forward in space, thus preserving balance. The body (and center, CM/CG) remains in a stationary vertical axis while the punch is projected horizontally. A strong base is required, and this is where a rooted stance and locked hips come in.

This can be demonstrated by facing a partner and placing a punch partly extended against his resisting palm. You try to push his hand back with your punch. Then, suddenly, he withdraws his hand. The likely result is that you will fall forward, unbalanced, or at least your punch will fly forward uncontrolled. This will not happen if proficient in sanchin.

Producing explosive power over (very) short distance is difficult to achieve and harder to explain. Imagine a battle between a submarine and destroyer. The destroyer drops a depth charge in close proximity to the sub. The charge detonates. The shock wave force travels thru the water and destroys the sub. The depth charge itself (think center) does not cause the damage. It, and the water itself does not travel, just the wave of energy produced by the explosion. As to the nature of the explosion and its effect in producing power, I can't explain in karate terms (but chinkuchi is involved). This is a skill that must be acquired (rather than taught IMO) over time by the individual, but I think the submarine example roughly illustrates the concept.

As you can see, there is no short answer . And this is only the way I personally visualize the answer to your questions. I really can't explain it - I just do it.

 

[windwalker099]

I really can't explain it - I just do it.

This practice reminds me of some Southern CMA practices
Most would refer to this practice as waijia (外家) or external practices use to focus and generate power.

For clarity:

Waijia (外家) is terminology that some might interpret as suggesting one practice is superior to another, rather than simply different. It is used to denote a focus of practice with specific expected outcomes from the practice.

One of the things sanchin kata does is teach projecting power without moving your center forward in space, thus preserving balance.The body (and center, CM/CG) remains in a stationary vertical axis while the punch is projected horizontally. A strong base is required, and this is where a rooted stance and locked hips come in.

Very nice post, in depth, comprehensive..