An Observation on Pivoting

[KPM]

Ok. Just so everything is clear, here is a little basic lesson on biomechanics for those that might be interested.
When gravitational force acts on an object it causes it to fall directly downward to the ground. When the object is long and relatively parallel to the ground, this force acts relatively equally on all parts of the object. But if the object is long and oriented relatively perpendicular to the ground, then gravity does not act on all parts equally. Instead, gravity will have its main effect on one spot within the object that serves as a sort of “balance point” where the object’s main mass is relatively centered. This is known as the “center of gravity.” For a human standing upright the COG is within the pelvis at approximately the spot Martial Artists refer to as the “Tan Tien.”
The force of gravity will exert a “pull” on the COG that is directed straight down to the ground. The vector line along which this “pull” is directed is variously known at the “line of gravity” the “gravitational line”, etc. When a human is standing upright in a relaxed posture this gravitation line is directed through the arch of the foot just in front of the ankle. This allows for balancing in the upright position with firing as few muscles as possible to maintain that posture. The arch of the foot is reinforced by the “spring ligament.” Thus the arch of the foot acts just like the strut on an automobile suspension. It absorbs and redistributes downward force. Your toes grip the ground and also contribute significantly to your balance. In order for the gravitational line to go through your heels, you would have to be leaning back so that your COG was directly over the heels. This would off-load the arch of your foot and take much of the balancing ability away from your toes. In short, this is a precarious position!
When we bend our knees and assume a Yee Gee Kim Yeung Ma stance, our COG shifts forward and is even further out over the arch of the foot. The gravitational line goes through the center of the arch of the foot, not through the heels. Again, in order for the gravitational line to go through the heels, the COG would have to be directly over the heels, which would require the person to be leaning back. Balance would be compromised.
When doing the Wing Chun pivot, if you pivot through a central vertical axis keeping the weight distributed 50/50 between the feet, the most optimal way to shift from a biomechanical perspective is to use the center of the arch of the foot as the pivot point. This is because the gravitational line is already going through this point. You can even bend your knees and sink deeper in your stance without altering this pivot point. You can bend your knees to the point that you are in a “Gwai Ma” stance and still pivot at the arch of the foot. Therefore, the optimal way to pivot while maintaining the best control of balance is to pivot through the arch of the foot.
If you pivot with your heels as the pivot point, you have to momentarily transfer the gravitational line from being through the arches of your feet to being through the heels. If you don’t do this, then the front part of your foot cannot “swing” as you pivot on your heels. Now when the front part of your foot is “swinging” with the pivot, then your toes are not engaged as well in controlling your balance. For that split second of the pivot, your balance is vulnerable to being disrupted. This is not to say that pivoting on the heels is wrong! People that practice it get good at it and can make it work! But from a biomechanical standpoint, it is not the optimal way to pivot.
When an external force is applied, as in engaging a partner or adversary that is pressing back into your structure, force may very well be directed into the ground through your heels. But this is no longer strictly the gravitational force and not the gravitational line.
This is just simple biomechanics. I hope everyone was able to follow along and understand what I am saying.

 

[JPinAZ]

This is why it's safe not to speak in absolute certainties telling someone they are 'flat wrong'. There are far too many factors to take into account before you make such a broad (and somewhat silly) statement.

---It is simple biomechanics. Nothing "silly" about it.

While yes, you are 'correct' in one regard, I can think of many instances where your above statement is incorrect. Try telling a ballet dancer their 'gravitational path goes thru the center of the arch of the foot' when they are up on their toes lol. And you better believe their weight is well balanced!

---Uh....in case you didn't realize....we are talking about Wing Chun here, not ballet.

From a WC POV, to 'receive' energy from an opponent thru your root and into the ground, it surely can go thru the heals, if even for a brief instant.

---But we were talking about pivoting in general. A specific case scenario was not what was being discussed. Joy made a general statement, and that general statement was flat wrong. End of story. You can nit-pick all you want. It doesn't change the biomechanics of it. In general, when you pivot your gravitational path does NOT go through the heels unless the majority of your weight is back over the heels.

In the end, really, what does it matter! If it works for someone, who are we to tell them they are 'wrong'?

---If you were actually paying attention, I did not say that the way they were pivoting was wrong. I said that Joy's statement of the "gravitational path" was wrong. There is a big difference there!

Good grief you're a touchy sort! I really only want to make this point once here, so excuse the directness. First off, if you want to have a sincere conversation here, you would do yourself and everyone else a favor by dropping the tone right now. It's really not necessary and doesn't make you any more 'right' (since you prefer to talk in terms of right/wrong). There is a reason this forum is a lot more pleasant than the 'other one' and I think it's good if we all do our best to keep it that way.

Interesting you say you were talking specifics of WC ("were talking Wing Chun here not ballet") and then in the very next breath you are talking "pivoting in general". But you were also talking 'gravitational paths' and biomechanics, neither of which is necessarily WC specific. So if you are going to take a condescending, passive aggressive attitude, it would be a good idea to at least be consistent. On second thought, again, it would be a better idea to drop the attitude altogether.

Fact is, taking a higher-than-thou position talking about right/wrong in regards to how WC moves when changing facing is silly if you are only talking generalities. And further silly if we also refuse to also see moving at all in WC is rather pointless without an opponent to relate to (you don't move, I don't move). And, how we do it varies greatly based on input/pressure from the opponent. So yes, the 'gravitational path' (silly term also IMO) does in fact change depending on input from the outside world. So I hope you can see for someone to say another is right/wrong when speaking 'in general' with little-to-no context or reference is pretty pointless.

One final note: I am really only interested in showing mutual respect with those I'm discussing with, regardless if I'm in agreement with them or not. If we can't keep it along those lines, no need to reply.

 

[JPinAZ]

I was originally taught the one foot at a time method. Now I use whatever's needed to move without giving up my balance/COG/ structure or any physical advantage I might have..My teacher once said after I asked why is our fighting stance 60/40? He said "it's not it's more of a reference or starting point. In fighting you'll always be transitioning..He used the example of walking and how weight is constantly being transferred from 0-100 to 100-0. If there was a rule that said we must walk at a maintained 60/40 we'd all look silly. So I feel the same about pivoting. The wrong way to pivot, is pivoting without forward intent and or over pivoting. Which to me is the exact same thing..

Great point!
In HFY, we also typically move one foot at a time when changing position, as well as picking them up so we don't 'get stuck' and have better opportunity to land our second foot so we are preferably in a superior position (you don't move, I don't move - you move, I 'get there' first). This gives us better ability to react to the input we are receiving from our opponent.
If we 'fix' both feet and just pivot to change facing in relation to our opponent's actions and/or pressure, we may end up giving up some of our personal/structural space if our opponent is overpowering us. Or, we may have to lean out of the way to compensate. Neither option IMO is the best route when working towards a goal of fighting maximum efficiency. We need to be able to adjust our stance as necessary to both retain our own personal space & full body structural alignment, as well as adjust our facing & superior position in relation to our opponent.

 

[geezer]

If you pivot with your heels as the pivot point, you have to momentarily transfer the gravitational line from being through the arches of your feet to being through the heels. If you don’t do this, then the front part of your foot cannot “swing” as you pivot on your heels. Now when the front part of your foot is “swinging” with the pivot, then your toes are not engaged as well in controlling your balance. For that split second of the pivot, your balance is vulnerable to being disrupted. This is not to say that pivoting on the heels is wrong! People that practice it get good at it and can make it work! But from a biomechanical standpoint, it is not the optimal way to pivot.

KPM, that was a pretty clear explanation and I agree with almost all of what you said, ...except the bolded part above. In my experience, there are three ways WC pivoting is commonly taught. 1. On the center of the foot ...or slightly toward the balls and turning one foot at a time in fluid sequence, 2. Turning both feet simultaneously with the weight back toward the heels and the front of the foot sliding or as you put it "swinging", and 3. turning both feet simultaneously with the weight forward on the balls of the feet toward the toes, with the heels sliding or "swinging".

Each of the above methods presents certain advantages and disadvantages in application. As I stated earlier, I prefer the one-leg-at-a -time, center-of-the-foot method for reasons we have both already stated. My issue with turning both feet simultaneously is that I feel equally vulnerable when shifting my CG forward to pivot on the toes or when shifting back onto my heels. This is especially true in mid-pivot.

On the other hand turning both feet simultaneously with the weight shifted forward to the toes or back to the heels minimizes friction between the foot and the ground and allows for a very fast pivot. And, in my experience, it is significantly easier to teach, and faster to learn and apply than the one-foot-at-a-time method I use. And, as you already noted, there are many experienced WC people who can make heel or toe turning work, So can you really say that these methods are biomechanically sub-optimal in all situations?

 

[Dirty Dog]

Ok. Just so everything is clear, here is a little basic lesson on biomechanics for those that might be interested.
When gravitational force acts on an object it causes it to fall directly downward to the ground. When the object is long and relatively parallel to the ground, this force acts relatively equally on all parts of the object. But if the object is long and oriented relatively perpendicular to the ground, then gravity does not act on all parts equally. Instead, gravity will have its main effect on one spot within the object that serves as a sort of “balance point” where the object’s main mass is relatively centered. This is known as the “center of gravity.” For a human standing upright the COG is within the pelvis at approximately the spot Martial Artists refer to as the “Tan Tien.”
The force of gravity will exert a “pull” on the COG that is directed straight down to the ground. The vector line along which this “pull” is directed is variously known at the “line of gravity” the “gravitational line”, etc. When a human is standing upright in a relaxed posture this gravitation line is directed through the arch of the foot just in front of the ankle. This allows for balancing in the upright position with firing as few muscles as possible to maintain that posture. The arch of the foot is reinforced by the “spring ligament.” Thus the arch of the foot acts just like the strut on an automobile suspension. It absorbs and redistributes downward force. Your toes grip the ground and also contribute significantly to your balance. In order for the gravitational line to go through your heels, you would have to be leaning back so that your COG was directly over the heels. This would off-load the arch of your foot and take much of the balancing ability away from your toes. In short, this is a precarious position!
When we bend our knees and assume a Yee Gee Kim Yeung Ma stance, our COG shifts forward and is even further out over the arch of the foot. The gravitational line goes through the center of the arch of the foot, not through the heels. Again, in order for the gravitational line to go through the heels, the COG would have to be directly over the heels, which would require the person to be leaning back. Balance would be compromised.
When doing the Wing Chun pivot, if you pivot through a central vertical axis keeping the weight distributed 50/50 between the feet, the most optimal way to shift from a biomechanical perspective is to use the center of the arch of the foot as the pivot point. This is because the gravitational line is already going through this point. You can even bend your knees and sink deeper in your stance without altering this pivot point. You can bend your knees to the point that you are in a “Gwai Ma” stance and still pivot at the arch of the foot. Therefore, the optimal way to pivot while maintaining the best control of balance is to pivot through the arch of the foot.
If you pivot with your heels as the pivot point, you have to momentarily transfer the gravitational line from being through the arches of your feet to being through the heels. If you don’t do this, then the front part of your foot cannot “swing” as you pivot on your heels. Now when the front part of your foot is “swinging” with the pivot, then your toes are not engaged as well in controlling your balance. For that split second of the pivot, your balance is vulnerable to being disrupted. This is not to say that pivoting on the heels is wrong! People that practice it get good at it and can make it work! But from a biomechanical standpoint, it is not the optimal way to pivot.
When an external force is applied, as in engaging a partner or adversary that is pressing back into your structure, force may very well be directed into the ground through your heels. But this is no longer strictly the gravitational force and not the gravitational line.
This is just simple biomechanics. I hope everyone was able to follow along and understand what I am saying.

You can use the word "biomechanical" and other buzz words as often as you like within your post. It won't make you any more correct.
The COG of a body in motion is not necessarily through the arch of the foot, nor is it inherently unstable to have that COG on the heel or the ball of the foot, or even on the toes. Balance and stability can be excellent with the COG in ANY of those places.
The only time the COG is directly through the arches is when the body is upright, in a narrow, square stance, and not moving.

In none of the stances pictured above will the COG be directly through the arches. None. The knife edge, yes. The ball of one foot and the heel of the other, yes. The balls of both feet, yes. But never directly through the arches.
Of course, I only have 40+ years in the marital arts and a Masters in human physiology, so what do I know?

 

[geezer]

Never said toes...

No, but you said BALLS!

 

[geezer]

Of course, I only have 40+ years in the marital arts and a Masters in human physiology, so what do I know?

Hey Dog, do you really have to keep reminding us of how OLD we are?


That said I basically agree that there is no "biomechanical" law at play here. In fact there are a lot of effective ways to accomplish WC Pivoting.

BTW cute illustrations. Not WC, but still cute.

 

[KPM]

You can use the word "biomechanical" and other buzz words as often as you like within your post. It won't make you any more correct.
The COG of a body in motion is not necessarily through the arch of the foot, nor is it inherently unstable to have that COG on the heel or the ball of the foot, or even on the toes. Balance and stability can be excellent with the COG in ANY of those places.
The only time the COG is directly through the arches is when the body is upright, in a narrow, square stance, and not moving.
View attachment 19597

In none of the stances pictured above will the COG be directly through the arches. None. The knife edge, yes. The ball of one foot and the heel of the other, yes. The balls of both feet, yes. But never directly through the arches.
Of course, I only have 40+ years in the marital arts and a Masters in human physiology, so what do I know?

I was talking about Wing Chun. Those illustrations are not Wing Chun. So yes, it is biomechanically correct the way I described it. With 40 years of experience and a masters in human physiology one would think you would be able to track the logic of what I was describing. ;-)

 

[Dirty Dog]

Hey Dog, do you really have to keep reminding us of how OLD we are?


That said I basically agree that there is no "biomechanical" law at play here. In fact there are a lot of effective ways to accomplish WC Pivoting.

BTW cute illustrations. Not WC, but still cute.

I don't do WC, so I googled "wing chun stances" and that popped up.

 

[Dirty Dog]

I was talking about Wing Chun. Those illustrations are not Wing Chun. So yes, it is biomechanically correct the way I described it. With 40 years of experience and a masters in human physiology one would think you would be able to track the logic of what I was describing. ;-)

I can track it. That's why I know it's wrong.

 

[KPM]

I can track it. That's why I know it's wrong.

Ok. Then explain what is wrong with what I described. Keep in mind I was talking about the YKGYM stance and the Wing Chun method of pivoting. Not any of the postures you illustrated.

 

[KPM]

Good grief you're a touchy sort!

---Well, you did call me "silly"! ;-)

I really only want to make this point once here, so excuse the directness. First off, if you want to have a sincere conversation here, you would do yourself and everyone else a favor by dropping the tone right now.

---Sorry, didn't mean to have a "tone." When describing things that are technical, it just comes across that way. And you did imply I told Joy that he does the pivot wrong, which I didn't. I only said that his comment on the gravitational line was wrong.



Interesting you say you were talking specifics of WC ("were talking Wing Chun here not ballet") and then in the very next breath you are talking "pivoting in general".

---In Wing Chun. Sorry, I thought that was obvious.


Fact is, taking a higher-than-thou position talking about right/wrong in regards to how WC moves when changing facing is silly if you are only talking generalities.

---I don't think applying biomechanical principles to Wing Chun is silly at all. And I was talking about Wing Chun, not life in general. I thought that was obvious as well.

And further silly if we also refuse to also see moving at all in WC is rather pointless without an opponent to relate to (you don't move, I don't move).

---You don't maneuver around the opponent for position from an outside range? You don't adjust your position and angling prior to contact? You don't practice solo? Sorry, but your statement sounds kind of silly to me!


So yes, the 'gravitational path' (silly term also IMO)

---That was Joy's term. But it is an appropriate term.

does in fact change depending on input from the outside world.

---It only changes when your relationship to the ground changes. If another force other than gravity is being applied, then it is no longer simply just the "gravitational line." Again, that's just simple biomechanics.

So I hope you can see for someone to say another is right/wrong when speaking 'in general' with little-to-no context or reference is pretty pointless.

---There was a context....standing and pivoting in Wing Chun. I thought that was clear. And the point was that the gravitational line does not go through the heels when standing. I thought that was clear as well. Did you read what I wrote?

One final note: I am really only interested in showing mutual respect with those I'm discussing with, regardless if I'm in agreement with them or not. If we can't keep it along those lines, no need to reply.

---I believe in mutual respect as well. I simply pointed out a false statement when it comes to biomechanics applied to Wing Chun. You chose to jump on that and say I was silly and that I was telling Joy he does things wrong (which I wasn't.) So to clear things up as to why I thought Joy had made a false or inaccurate statement I wrote out an explanation. I was trying not to be one of those guys that just criticizes and doesn't explain. But rather than say "thanks for the explanation", I get this. So gee Jonathan, maybe you're the one that is "a touchy sort"! ;-) And you know, that last I checked Joy is an adult and can speak for himself.

 

[Dirty Dog]

Ok. Then explain what is wrong with what I described. Keep in mind I was talking about the YKGYM stance and the Wing Chun method of pivoting. Not any of the postures you illustrated.

I did. Apparently you didn't understand it. That's OK.
I'll try to keep this as simple as possible.
The ONLY time the COG is through the aches is in a narrow, upright, stationary stance. That's it.
As soon as you start to move, the COG shifts out of the arch. Always.
If you still don't get it, then I have to assume you're being intentionally obtuse.

 

[KPM]

I did. Apparently you didn't understand it. That's OK.

---No you didn't. You made statements. You did not back them up by explaining the biomechanics. You showed pictures that have nothing to do with Wing Chun.

The ONLY time the COG is through the aches is in a narrow, upright, stationary stance.

---Which is what I was describing.

As soon as you start to move, the COG shifts out of the arch. Always.

--Unless you are doing a Wing Chun pivot with body upright and weight distributed approximately 50/50....which, again, was what I was describing.

If you still don't get it, then I have to assume you're being intentionally obtuse

---If you still don't get it, maybe it is because you don't actually do Wing Chun? Or are you just being an ***?

 

[KPM]

KPM, that was a pretty clear explanation and I agree with almost all of what you said,

---Well Steve, I'm glad someone was able to follow what I was saying! Who is this "Dirty Dog" guy anyway?

In my experience, there are three ways WC pivoting is commonly taught. 1. On the center of the foot ...or slightly toward the balls and turning one foot at a time in fluid sequence, 2. Turning both feet simultaneously with the weight back toward the heels and the front of the foot sliding or as you put it "swinging", and 3. turning both feet simultaneously with the weight forward on the balls of the feet toward the toes, with the heels sliding or "swinging".

---True. I didn't address the differences between your #1 and #3. But I would also have to say that #1 and #3 are both more biomechanical "optimal" than #2.

My issue with turning both feet simultaneously is that I feel equally vulnerable when shifting my CG forward to pivot on the toes or when shifting back onto my heels. This is especially true in mid-pivot.

---But I'm not sure anyone really pivots with both feet at exactly the same time. I certainly don't! And the COG never shifts completely forward to the toes. It shifts forward over the point you are pivoting around, which is not the toes. It is usually close to K1.


And, as you already noted, there are many experienced WC people who can make heel or toe turning work, So can you really say that these methods are biomechanically sub-optimal in all situations?

---Yes, you can! Being able to make it work well is not the same as saying as saying it is "optimal". I'm sorry that others don't seem see the logic in what I am saying. And I am not pulling this out of my ***. I have trained in this. Normal and abnormal gait mechanics is part of what I teach to our medical residents. I'm just applying this to a Wing Chun structure. Its really very simple....having the majority of your weight back over your heels (even for just a moment) is less stable than keeping the majority of your weight over the arch of your foot. This is true when standing as well as moving around.

 

[Jake104]

Correct! You have a wise teacher.

Thanks! It was my first teacher, but I believe all have been in sync with this type of thinking.

Like I said in my last post. My preference is whatever works at that moment. I think where it's important is in teaching a new student. A foundation needs to be laid for that student, so id probably teach the one foot at a time method. Just cause that's how I learned. But with emphasis later on that there our other methods of pivoting and that the circumstance dictates the action

 

[geezer]

View attachment 19597

OK guys, let's be fair. Some of Dirty Dog's stance pictures do relate to WC, just not to the stances we're discussing. Gotta go to the pole form. For example, check out the first picture he posted above (a guy in a horse stance with his arm extended to the side) and compare it to our WC "Battle Punch" below (sorry for the dark photo. I had a hard time finding a good image on google... this one's of a guy here in my town associated with Sam Kwok, I believe):

http://i.ytimg.com/vi/uWqJGCaDMNM/hqdefault.jpg

 

[Argus]

We do both.
Something I asked of my sifu many years ago while observing his movement. His reply, "Ahh, sometimes on the ball of your foot, sometimes on the heel. We use whatever we need to do depending on what is needed. After you learn it, understand it, then do what is natural, just move."

SLT no movement, Chum Kiu we pivot on the ball, Bil Jee we pivot on the heel, after that just move.

I rather like this approach.

I used to consider that I always pivot on the heels, but even when trained in a lineage claiming to do that, I found myself and others sometimes shifting on the balls when necessary. It kind of hit me in my own practice when I noticed that as I shift and step back/offline with tui-ma, for instance, the position is exactly the same as if I merely shifted on the balls of the feet. The only difference is that in the first method I pivot and then step back, and in the second, I accomplish the same thing by merely pivoting on a different point. But the first motion tends to kind of mesh into the second at speed, and you wind up doing essentially the same motion regardless. So, it seems quite suited for getting offline quickly you're out of contact.

I do prefer to pivot on the heels when striking, though, as it allows me to stay in range easier. I noticed that when I was doing some of the footwork we practiced in Pekiti, stepping offline and pivoting on the balls, I was consistently missing the target by a few inches, whereas I had been hitting with the tip before I moved, because I'm not used to pivoting there. And sure enough, when I did the same step and pivoted on the heels, I was hitting as I was before!

I don't guess we're allowed to pivot on the heels in Pekiti though, are we? Or are we?

 

[Argus]

As for pivoting on the "K1 point," which I take to be the arc of the foot (not the ball or heel)...

Physically, I'm failing to see how this is possible. There's no point on which to turn, as the arc of the foot is not in contact with the ground. I have seen a Yuen Kay San guy describe and show me this method, and it just looked like he was pivoting on the balls to me.

KPM: "having the majority of your weight back over your heels (even for just a moment) is less stable than keeping the majority of your weight over the arch of your foot. This is true when standing as well as moving around."

Now, this I agree with! I think most practitioners with good structure keep their weight over their arches, regardless of where they shift. At least, this is what I do. The weight does not necessarily need to be directly over the pivot point.

 

[Marnetmar]

Of course, I only have 40+ years in the marital arts and a Masters in human physiology, so what do I know?

Not as much as me. I wrote this post with MY MIND.