Is Lag from the left shoulder through impact possible?

[wulsy]

Ho ho ho. Strangely enough my face is devoid of damage caused by anything other than accidents. Probably because I'm such a great guy in real life.

Some people think it's cool and sophisticated to criticise others whilst talking pish themselves, blissfully unaware of their own cluelessness and lack of manners.

Was that "wulsy" enough for you dudes?

 

[spktho]

Not arguing, or commenting except that - make sure you are using the term properly - Radial Force IS up the shaft.

Thanks for the correction. I will edit it to across the shaft. You have a valid point, I was merely trying to take the pureness of the endeavor into account.

 

[Mike O]

It is my understanding on this issue that their studies show any force across the shaft from the hands/pivot occurs somewhere in the transition and in the downswing--the timing is individual and there is more than likely an individual optimum. By the time impact comes, there is a negligible to no force across the shaft from the hands. The force measured near and at impact from the hands is up the shaft or toward the golfer.

Agreed -
One of my points was, that doesn't mean that there is no lag pressure, as I defined it, opposed to how Brian envisioned it.

 

[Mike O]

Ho ho ho. Strangely enough my face is devoid of damage caused by anything other than accidents. Probably because I'm such a great guy in real life.

Some people think it's cool and sophisticated to criticise others whilst talking pish themselves, blissfully unaware of their own cluelessness and lack of manners.

Was that "wulsy" enough for you dudes?

Ah, you're under-estimating me my "friend", I'm fully aware of what I'm doing and the issues involved.

 

[dbl]

Mike O, forgive me if I didn't catch your meaning. From what I can see you have a strong background in TGM. How much of that system colors your ideas today, and do you have a strong allegiance?

 

[Mike O]

Mike O, forgive me if I didn't catch your meaning. From what I can see you have a strong background in TGM. How much of that system colors your ideas today, and do you have a strong allegiance?

That's a painful question to answer - from where I come from - I'm thinking "are you kidding me?" However, you've really left me no room not to answer it. Corny as it may sound, my only allegiance is to the truth and reality. I don't have allegiance to a system, never did. How much of that system colors my ideas today? 1-5%, although I don't like the question nor the answer.

Here's why I have the reaction "Are you kidding me?" - To me, it doesn't matter if someone has an allegiance to a system when they post, it's irrelevant to me. Ideas either are true or false, I don't care if someone has an agenda as long as they can communicate their ideas and you can judge those ideas as right or wrong - with a little civil discourse. It's when their agenda or allegiance makes it impossible to have a rational conversation, that it becomes a problem.

So terms such as "allegiance to a system" or letting a "system color your ideas" are the exact opposite of a true researcher. That would be someone who doesn't have any respect for the truth or reality. That's why you see me asking questions about someone's ideas, you don't see me asking people about their agenda, or their allegiance to some system or scientist. (And that last sentence was meant as an example of my overall approach, a clarification - it was not meant as a dig at you. One of those communication issues I wouldn't need to clarify my intent in person but can be mis-interpreted in print)

Bruce Lee:
Too much horsing around with unrealistic stances and classic forms and rituals is just too artificial and mechanical, and doesn't really prepare the student for actual combat. A guy could get clobbered while getting into this classical mess. Classical methods like these, which I consider a form of paralysis, only solidify and constrain what was once fluid. Their practitioners are merely blindly rehearsing routines and stunts that will lead nowhere.
I believe that the only way to teach anyone proper self-defence is to approach each individual personally. Each one of us is different and each one of us should be taught the correct form. By correct form I mean the most useful techniques the person is inclined toward. Find his ability and then develop these techniques. I don't think it is important whether a side kick is performed with the heel higher than the toes, as long as the fundamental principle is not violated. Most classical martial arts training is a mere imitative repetition - a product - and individuality is lost.
When one has reached maturity in the art, one will have a formless form. It is like ice dissolving in water. When one has no form, one can be all forms; when one has no style, he can fit in with any style.

 

[wulsy]

Ah, you're under-estimating me my "friend", I'm fully aware of what I'm doing and the issues involved.

It wasn't directed at you Mike. You've shown yourself to be a level headed enquirer seeking answers to questions, with civility and balance in you views and responses. Like many others here. That's why I'm still here.

 

[Mike O]

It wasn't directed at you Mike. You've shown yourself to be a level headed enquirer seeking answers to questions, with civility and balance in you views and responses. Like many others here. That's why I'm still here.

My apologies.

 

[BerntR]

These questions were brought up by BerntR about a week ago.

Best I can figure, these are the points you are making.

1. Since the left shoulder is "in front of" the sweetspot, no matter how much you are pulling up on the grip, no matter how much the shaft is bending forward, the sheer sweetspot being "behind" the left shoulder, and the left shoulder is attached to the arm, and the arm is attached to the hand, and the hand is holding the grip—then the left shoulder is moving the club forward just pre-impact and at impact.

Yes. Lag all the way through the ball.

2. The forward part of the pulling of the left shoulder creates lag pressure—which is by definition, pressure on the backside of the shaft—and this lag pressure increases as a response to the impact shock—pre-impact—and that this happens fast enough to make a difference to the ball compression.

No, not pressure on the backside of the shaft. Axial tension in the shaft. Just from pulling. Like a tight rope. The same as the radial force you've been talking about. I think we agree that this is an axial force, that runs straight up and down the shaft. But you say it is radial (towards the center), while I say it is radial and tangential (towards the center and forward)

The tangential component in the axial force has been overlooked, IMO.

I can't see that lag pressure has been defined with regards to "bending the shaft" type of pressurizing. I am aware that this is how the term is usually applied. There are at least three ways to pre-stress a shaft. You can bend it, torque it and you can stretch it like a rope.

I use lag pressure about tangential, axial force. Because there's pressure and lag there. But perhaps a new term is needed to avoid confusion with "bending the shaft" lag pressure.

3. I think Homer Kelley was onto something important with his definition of rhythm & a flat left wrist maintained through forearm rotation doesn't change that.

Homer's definition of rhythm: Holding both Lever Assemblies to the same basic RPM throughout the stroke while overtaking all other components at a steady, even rate.

IMO, this was misleading as far as attributing left arm and club to the same RPM. Also, I don't know about the steady, even rate. But to me anyway, one of the big challenges and mysteries of the good golf stroke is how to synchronize the shoulder turn, the arms swing, the release of the wrist cock and the gradual closing of the club face so that all arrive properly aligned at impact without any steering.

I was also thinking about your own experiences and reflections with regards to the flat left wrist here and at other forums. I understand that you regard it is pointless, correction: counterproductive, to force a flat left wrist post impact. And that makes sense even to me. Because there is overtaking going on between the club and the left arm in any case. Whether you let the left wrist collapse past impact or whether you "force" it to remain flat by rotating the forearms quickly so that the club head can get past the hands without a left wrist breaking down doesn't change that.

I only brought this up to establish some common ground. I guess I could have done better.

And, I may be 100% wrong, but here are my answers to those questions based on my 30 years of experience and last few years of research with real scientists.


1. Any "lag pressure" at impact is incidental and has no bearing on the impact collision and the distance the ball travels.

2. Nothing going on just before impact, as a response to the impact shock—pre-impact, has any bearing on the impact collision or distance.

You may be right and you may be wrong. But this hasn't been properly investigated as far as I can see. And it may be worthwhile exploring. The findings could have implications on club making.

I've seen Mandrins analysis of this. It accounts for shear forces, the "bending the shaft" type of pressure. And for those forces the conclusion seems plausible.

Tangentially, a club with a stiff shaft typically can have a flex in the region of 300 rpm. That is 5 rp second, corresponding to a frequency of 5 Hz. Which means that the shaft takes around 200 ms to flex back, forward and back to zero. And it will take 50 ms to even start rebounding from a collision with the ball. The ball is long gone by then so Mandrin was right on that account.

But this is how the shaft responds tangentially. The shaft itself responds almost infinitely faster axially than tangentially.

The speed of sound in graphite and steel is 5600 meter per second. If you hit the ball while still pulling from the left, the impact shock will reach the hands after 1/5600 seconds = 0.18 ms if the club is 1 meter long. Which isn't totally out of the ball park. What happens during that interval is that the shaft stretches a tad. Like a rubber band. Even the most inflexible materials as a tiny bit of elasticity. But after 0.18 ms the shaft is stretched enough to hold the new load and respond to the impact shock.

According to Mandrin http://www.brianmanzella.com/golfing-discussions/7554-golf-impact-physics.html, the impact interval has a duration of approx 0.4 ms.

So, a shaft that recovers in 0.18 ms is fit for fight for half the impact interval. Your brain may not detect what happens before the ball is long gone, but your brain and your hand's doesn't even know that the club head has collided with the ball before the shock is transmitted to the hands, so they just keep the momentum going. And when the shock arrives at the hands, the hands is yet again fully connected with the sweet spot and if the ball is still glued to the club face you can apply force directly to the ball.

This is a highly idealized situation and there are a few factors that will make this less effective in real life:

The shaft is in a bent condition at impact since the sweet spot has an offset to the shaft orientation. The shaft bending increases the effective length of the club and it can probably increase some more when the club head meets the ball. The glue that attaches the shaft to the head is very flexible compared to steel and graphite, and then of course we have the grip which is also flexible.

All these factors are likely to absorb some of the impact shock, and delay the arrival time at the hands.

But on the other hand, the shaft itself has moving mass and I would be highly surprised if the moving mass doesn't make a difference before the ball has left the club head. More so with the mass close to the club head and less so with the mass farther up the shaft. It is just a matter of how much and how far up the shaft (and hands and arms) the shock goes before the ball has left the club face.

I bet it is possible to make non-conforming club where the moving mass in the grip and above will make a significant difference to impact - at least if the ball is hit by a machine.

3. I think that any idea of rhythm in the golf swing, as per TGM, is closer to being 100% wrong than 100% correct.


I may be 100% wrong, and Bernt you may be correct.


But, I will find the answers and put them up here.


Please correct me, if I have any of your premises incorrect.

3. At least I agree that he got the explanation wrong. I'm not sure what the valid alternative to some form of rhythm is though. I'm all ears here.

The tangential component of the pulling was anyway the reason I started the other thread. I am convinced that it is extremely important.

I really appreciate that you've decided to look into this and I will be looking forward to the proceedings.

 

[dbl]

Mike, a thoughtful answer. It just seemed to me from your post #10 that no one would ask such questions about finite analysis when there seems to a very high chance (like 90%+) of the answer being negative...unless a prior framework might suggest (or "need") a major flaw in the premise.

In any case, when you quoted BM about "creating lag..." from his post #9...your question is not very clear to me since Brian was writing his interpretation (at that time) of Bernt's view.

BM "creates lag pressure—which is by definition, pressure on the backside of the shaft"

Brian, I've seen you posting ideas over and over which have puzzled me or not made any sense to me.

Your quote (whose?????) above of Bernt's view of lag really isolates the issue, in regards to why I've had this disagreement in my mind.

Could you rewrite your question more clearly, please?

 

[Mike O]

Mike, a thoughtful answer. It just seemed to me from your post #10 that no one would ask such questions about finite analysis when there seems to a very high chance (like 90%+) of the answer being negative...unless a prior framework might suggest (or "need") a major flaw in the premise.

In any case, when you quoted BM about "creating lag..." from his post #9...your question is not very clear to me since Brian was writing his interpretation (at that time) of Bernt's view.




Could you rewrite your question more clearly, please?

DBL,
I see your point regarding the second paragraph in your quote above, that is, I did view the "by definition lag is behind the shaft" as Brian's comment/interpretation - and not Bernt's view (regardless of what Bernt's view was), so that may have been an error on my part. However, from the general discussion of the release thread and comments Brian has made - I gathered it was his view (regardless of what Bernt's view was) -, your point is well taken in that regard - I could have mis-read that.

Not sure on the first paragraph - what you mean - I'd need to go back and read everything again - or you could rephrase it. Same with re-writing my question.

 

[dbl]

For the the lag part, it seems Brian is not very interested in any fictional or nonfictional non-axial forces near impact. So lag pressure as Bernt was saying isn't part of Brian's concern.

As far as my comment about finite element analysis*, you have more interest than i do about the possibliity of error in that regard, so I will leave it to BM and MJ to answer that concern. I just do not particularly think chopping up the swing into pieces leads necessarily to errors about parts way upstream. Given that you think you spotted something, fine, but preimpact lag might just be "eliminatable" by any of us as a concern from what the scientists have already told BM/MJ and in essence, at some point, the clubhead is just acting like a projectile with dynamics programmed much earlier in the impact sequence. If the latter part of the prior sentence is true then the main issue is finding the point whereby the the dynamics are locked in and where earlier you can have some real input. Before that point then your concern would have more validity, imo.

* Finite element method - Wikipedia, the free encyclopedia

 

[Mike O]

For the the lag part, it seems Brian is not very interested in any fictional or nonfictional non-axial forces near impact. So lag pressure as Bernt was saying isn't part of Brian's concern.

As far as my comment about finite element analysis*, you have more interest than i do about the possibliity of error in that regard, so I will leave it to BM and MJ to answer that concern. I just do not particularly think chopping up the swing into pieces leads necessarily to errors about parts way upstream. Given that you think you spotted something, fine, but preimpact lag might just be "eliminatable" by any of us as a concern from what the scientists have already told BM/MJ and in essence, at some point, the clubhead is just acting like a projectile with dynamics programmed much earlier in the impact sequence. If the latter part of the prior sentence is true then the main issue is finding the point whereby the the dynamics are locked in and where earlier you can have some real input. Before that point then your concern would have more validity, imo.

* Finite element method - Wikipedia, the free encyclopedia

Thank you for your thoughtful statement reclarifying your original question. I understand what you are saying now and I can answer that - be back at you soon.

 

[Mike O]

For the the lag part, it seems Brian is not very interested in any fictional or nonfictional non-axial forces near impact. So lag pressure as Bernt was saying isn't part of Brian's concern.

As far as my comment about finite element analysis*, you have more interest than i do about the possibliity of error in that regard, so I will leave it to BM and MJ to answer that concern. I just do not particularly think chopping up the swing into pieces leads necessarily to errors about parts way upstream. Given that you think you spotted something, fine, but preimpact lag might just be "eliminatable" by any of us as a concern from what the scientists have already told BM/MJ and in essence, at some point, the clubhead is just acting like a projectile with dynamics programmed much earlier in the impact sequence. If the latter part of the prior sentence is true then the main issue is finding the point whereby the the dynamics are locked in and where earlier you can have some real input. Before that point then your concern would have more validity, imo.

* Finite element method - Wikipedia, the free encyclopedia

Quick Answer:
The something I "spotted" was a principle - I've seen it so many times in my studies. In a previous post I called it "isolationism" and it's different in many ways than Finite element method - which doesn't really apply in this context - let me explain. When you have an expert from a certain field i.e. scientist, engineer, chiropractor, biologist, etc. and they use their area of expertise to make a statement on another field i.e. movement, they will observe a fact, then make a conclusion which seems obvious, WHILE ignoring an ESSENTIAL fact of the field they don't specialize in.

When I said you can't take a part of the swing and isolate it without understanding the parts around it, here's the broad explanation of that. Knowledge isn't created in a vacuum, it's created in a context, that context includes "everything", when new facts (let's keep it simple here - and call them major facts) arise it changes the entire context of your knowledge base - why? because it's all related.

How can these "scientist" get things wrong? (Keep in mind - I'm not saying everything that Brian has brought up is wrong - sure I saw one thing and I saw the principle involved, and my post labeled Free Guidance was to say "you better be careful otherwise you're going to have some real problems if you're putting all your money on the scientists".) I'll describe one large of many categories of these mistakes, in regards to the principle, which is the difference between observation of the movement as opposed to implementation of the movement.

Examples (fictional - to clarify and simplify the issue):
Scientist studies the down the line view of the top players in the world - notice that they don't stay on the same plane - that they shift up at 1/2 way back to a steeper plane. Tells his students - at half way back you need to increase the angle from 30 degrees to 50 degrees, as every pro does this. Not realizing that the pro(s) aren't trying to shift planes- they are making an effort to move in one plane on the backswing and anatomical issues create shifting.

Scientist studies backswing lengths for hand travel by taking high speed video - determines that top pros all take it to point A, all amateurs only take it to point B - instructs students to take their hands to Point A before starting the downswing. Not realizing that pros are only trying to take their hands to point A minus 6 inches, the final 6 inches is momentum carrying them to Point A even though the player as already initiated the downswing.

Let's go to your paragraph - I'm going to save myself some time and just give the essence of what I see. Scientist- "Nothing after the ball leaves the clubface affects it's flight - so what you do in the follow-through doesn't matter". "Right before impact there is no lag pressure - so you don't need to worry about that". "There is nothing you can do once the club is released". "So, really we just need to figure out on a procedural level what to do up until the point of release, becuase after that you can't control it". Now, it boggles my mind, assuming someone has played this game for over a couple of months how you wouldn't intuitively understand that key aspects of attention through impact, through the follow-through and finish - are critical elements of the mind. On a more scientific level the "scientist" who doesn't understand how movement takes place and how the Brain works, has missed the ESSENTIAL nature of movement. That it takes into account the past, present and FUTURE. Memory is a tool to predict the future. Every time you move you are making a prediction based on your prior experiences. So there is a focus on the future, those items past the time where your scientist said "it doesn't matter", because that controls the past and vica versa.

What's happening and What you try to do - are two completely different things.

 

[BerntR]

For the the lag part, it seems Brian is not very interested in any fictional or nonfictional non-axial forces near impact. So lag pressure as Bernt was saying isn't part of Brian's concern.

I am not very interested in non-axial forces near impact either. The lag pressure I have been pressing forward here is 100% carried by axial force. It was the whole point of starting the thread. How can you not have seen that?

 

[Mike O]

I'm definitely in agreement with BerntR on that point.

 

[Frans@France]

...When you have an expert from a certain field i.e. scientist, engineer, chiropractor, biologist, etc. and they use their area of expertise to make a statement on another field i.e. movement, they will observe a fact, then make a conclusion which seems obvious, WHILE ignoring an ESSENTIAL fact of the field they don't specialize in. ...

I cut a large part of the posting but tried to keep some essential part. Somehow when this is explained to Brain and others it seems they have trouble understanding this. They feel you must have a hidden agenda and are trying to discredit them. That is a real shame and hurts the search....

 

[Frans@France]

....Axial tension in the shaft. Just from pulling. Like a tight rope....
....The shaft is in a bent condition at impact.....

I could have quoted also the part about the cpm readings and the consequence for the impact wave etc for the tangentially force but the used foundation of that posting (single cpm frequency) is imho so incorrect that then we needed to start discussing the profile of a shaft before we could really discuss the math used.

However discussing it like that would mean that we discuss only the behaviour of the shaft during impact and already would accept that the hands are able to apply force to the grip. To me that seems that you start halfway in the discussion. You already made that assumption in your posting that you can still move your hands (and wrist uncocking) faster then the speed of the grip during impact, which data do you have to prove that that is indeed possible?

I decided however to quote the two lines that are also to be found in your posting. You are comparing pulling a tight rope with a bend shaft. You have made no statement how long it would take to get from the s-shape of the shaft to the "tigh rope" allowing to "hand to apply force"

 

[dbl]

Originally Posted by dbl
For the the lag part, it seems Brian is not very interested in any fictional or nonfictional non-axial forces near impact. So lag pressure as Bernt was saying isn't part of Brian's concern.

I am not very interested in non-axial forces near impact either. The lag pressure I have been pressing forward here is 100% carried by axial force. It was the whole point of starting the thread. How can you not have seen that?

I realize you're saying there is lag or nonaxial force resolution "somewhere"; I'm saying Brian's answer was limited to "near impact" (his answers numbered 1 and 2).


ETA: Oops, got the authors mixed up here. Mike O had the post about intention
As to the longer dissertation on intention etc, there is agreement that pre-release factors and dynamics are initiated and pre-planned. I can get on a plane in the midwest headed for New York that is preplanned to go to Miami first. We can get to the far reaches of the solar system by slingshotting around Jupiter, etc.

I agree some errors can at times be introduced by overlooking the "whole" when slicing up and analyzing small bits, but I'm not real convinced the team is doing that. BTW, Finite Element Analysis does involve some simplification so that there can be solvable problems; BUT such has to match reality, and that can be tested.

Nonetheless in regards BManz/MJ's investigations, I also fully expect Project 1.68 to be a living breathing document and that the version 10 years from now will be substantially improved from the initial version.

 

[BerntR]

However discussing it like that would mean that we discuss only the behaviour of the shaft during impact and already would accept that the hands are able to apply force to the grip. To me that seems that you start halfway in the discussion. You already made that assumption in your posting that you can still move your hands (and wrist uncocking) faster then the speed of the grip during impact, which data do you have to prove that that is indeed possible?

I decided however to quote the two lines that are also to be found in your posting. You are comparing pulling a tight rope with a bend shaft. You have made no statement how long it would take to get from the s-shape of the shaft to the "tigh rope" allowing to "hand to apply force"

Let's just say that you've got the wrong idea about my ideas.

Either I have turned into an incredible poor writer or you haven't used your reading skills. Either way I see no point in trying to clarify matters any further. The seven different ways or so I've laid it out it already will have to do.