Michael Finney
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My money is on McGill's understanding of Gracoversky's model - not yours or Kelvin's. I'll find the emails - at home now watching guys dunk using the spine engine.
Take a look at the educational bios and you make the call....
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tongzilla
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Michael Finney
New
Wait….did you just post a table of contents to describe Gracovetsky's model of the spinal engine? Here ya go…
Stu McGill
Getting back to these spinal engine and these theories of Doctor Gracovetsky, he was a brilliant engineer and very persuasive speaker. He came up with his colleague, Harry Farfan at the time, who was a spine surgeon who had theories on how the spine worked. He would say things like, “Well, the muscles of the spine are not strong enough.” Now let’s look at this power lifter picking up 400 Kilos from the floor. There’s no way the spine muscles are large enough. Therefore, there must be mechanisms that we do not understand or are in current models. So he came up with the lumbodorsal fascia theory where the fascia gets stretched behind the muscles and takes some of the load. And increases the mechanical advantage of the extensors and this sort of thing..
But when I went at it with my model, I in those days had something like 96 lips of muscle. Everything that crossed the low back and if you take an MRI slice through the lumbar spine, you will see the lumbar musculature cutting cross-section and you’ll measure its size. What you don’t realize is there are muscles all the way up the back that also contribute to that force. But when they are at the lumbar level through the layer of the skin, they’re just a little tendon so you can’t see the muscle. So the fact that his models were ignoring all of this musculature, the latisimmus dorsi, big lat muscles working through the fascia, I didn’t think it was anatomically accurate. If you just captured the anatomy correctly, you didn’t need these very esoteric explanations about how the back was. In fact, it became quite simplified. Then his ideas on when we walk, we move the hips.
Stu McGill
Getting back to these spinal engine and these theories of Doctor Gracovetsky, he was a brilliant engineer and very persuasive speaker. He came up with his colleague, Harry Farfan at the time, who was a spine surgeon who had theories on how the spine worked. He would say things like, “Well, the muscles of the spine are not strong enough.” Now let’s look at this power lifter picking up 400 Kilos from the floor. There’s no way the spine muscles are large enough. Therefore, there must be mechanisms that we do not understand or are in current models. So he came up with the lumbodorsal fascia theory where the fascia gets stretched behind the muscles and takes some of the load. And increases the mechanical advantage of the extensors and this sort of thing..
But when I went at it with my model, I in those days had something like 96 lips of muscle. Everything that crossed the low back and if you take an MRI slice through the lumbar spine, you will see the lumbar musculature cutting cross-section and you’ll measure its size. What you don’t realize is there are muscles all the way up the back that also contribute to that force. But when they are at the lumbar level through the layer of the skin, they’re just a little tendon so you can’t see the muscle. So the fact that his models were ignoring all of this musculature, the latisimmus dorsi, big lat muscles working through the fascia, I didn’t think it was anatomically accurate. If you just captured the anatomy correctly, you didn’t need these very esoteric explanations about how the back was. In fact, it became quite simplified. Then his ideas on when we walk, we move the hips.
ZAP
New
As a complete outsider without and kind of "horse in the game" I cannot believe this disagreement is still going on. The discussions that spring from these arguments are often illuminating for me personally so in some ways they are positive. At some level though it feels like the time spent trying to persuade the other side might be wasted or at least used in other ways.
Don't take this as criticism at all because I am really thankful for all the things I have learned from Brian, Mike and company. I just felt like it might be good for you guys to hear a perspective from the outside.
Don't take this as criticism at all because I am really thankful for all the things I have learned from Brian, Mike and company. I just felt like it might be good for you guys to hear a perspective from the outside.
Michael Finney
New
Hip decel - loss
Club face stability demonstrated post impact - loss
Spinal engine - big loss
"Experts" - embarrassing loss
Having Rich Hunt as your only friend - priceless
Club face stability demonstrated post impact - loss
Spinal engine - big loss
"Experts" - embarrassing loss
Having Rich Hunt as your only friend - priceless
Michael Finney
New
Yes ZAP....hope the best for your Dad
I would like to play a round with Rich Hunt....just think of all the people he knows and how he can top any story anyone else tells. The round would just fly by and the memories of all those wonderful stories Rich would spin...ah ...priceless!
Pretty sure Tapio is Jeff Martin's bestie and would be in his foursome.
Pretty sure Tapio is Jeff Martin's bestie and would be in his foursome.
Michael Finney
New
"ignoring all of this musculature"
You can't make this stuff up.....
Huge loss....
You can't make this stuff up.....
Huge loss....
Michael Finney
New
Because it is listed in a table of contents that means it is included in his model? What planet are you on?
Michael Finney
New
Could it be that Gracovetsky's Three Dimensional Model of the Human Spine might be slightly different than the Three Dimensional Model of the Spinal Engine….
This is typical of a line drawer who throws stuff out there to see if it sticks. Jeffy will want you to believe that Gracovetsky's model includes everything covered by the X…..Stu McGill will let you know that Gracovetsky's model includes a limited part of the spine which would roughly coincide with the red circle and be shaped like a cylinder around the spine. Because of this limited model, Gracovetsky had to assign force contributions to the fascia nearby to make the model work….
rogerdodger
New
Well done Mike, amazing what you see when a strong light shines.
Michael Finney
New
The spine engine has been completely panned. The spine engine's applicability to the golf swing is a leap that only you and Kelvin Miyahara can make.
Kelvin posts that the spine engine "truly drives the swing" and you try to dance your way out of that claim when years after you discover you misinterpreted the meaning of "primary" all along.
You then attempt to end the Gracivetsky - McGill debate by saying that McGill's model hasn't been proven on humans. Well, where is the proof that Gracovetsky's counter rotation adds any horsepower to the torso's angular speed in the golf swing? Where is the study? Where is it? Kelvin's line drawing is meaningless - it's just another stab at combining one esoteric, unproven spine theory with observational "seems as if" and call it scientific.
Can't make this stuff up!
Kelvin posts that the spine engine "truly drives the swing" and you try to dance your way out of that claim when years after you discover you misinterpreted the meaning of "primary" all along.
You then attempt to end the Gracivetsky - McGill debate by saying that McGill's model hasn't been proven on humans. Well, where is the proof that Gracovetsky's counter rotation adds any horsepower to the torso's angular speed in the golf swing? Where is the study? Where is it? Kelvin's line drawing is meaningless - it's just another stab at combining one esoteric, unproven spine theory with observational "seems as if" and call it scientific.
Can't make this stuff up!
Michael Finney
New
McGill speaks:
Our "model" accounted for muscles, ligaments, the lumbodorsal fascia, intra-abdominal pressure, full 3D motion and has compared experimental results with human data from our lab and many others. It continues to develop in several labs around the world - mainly because it produces results that compare to real life.
Our "model" accounted for muscles, ligaments, the lumbodorsal fascia, intra-abdominal pressure, full 3D motion and has compared experimental results with human data from our lab and many others. It continues to develop in several labs around the world - mainly because it produces results that compare to real life.
Michael Finney
New
Jeff Martin:
"Where can we find the peer-reviewed paper that confirms experimentally the conclusions of McGill's 1986 paper that Gracovetsky references in his book?"
My burden of proof is specific peer reviewed papers while yours is: IT STANDS TO REASON
"It stands to reason that if the forces inducing right-side lateral bend (gravity acting on the upper body, which represents about 60% of a human's mass, plus the contraction of the lateral flexors) are converted, through the coupled motion of the spine, into a counter-clockwise axial torque applied to the pelvis, incremental torque is added to power pelvic rotation."
What is your definition of "incremental" in this case? Make up some numbers for us - and run with it for a few years.
Can't make this stuff up…..
"Where can we find the peer-reviewed paper that confirms experimentally the conclusions of McGill's 1986 paper that Gracovetsky references in his book?"
My burden of proof is specific peer reviewed papers while yours is: IT STANDS TO REASON
"It stands to reason that if the forces inducing right-side lateral bend (gravity acting on the upper body, which represents about 60% of a human's mass, plus the contraction of the lateral flexors) are converted, through the coupled motion of the spine, into a counter-clockwise axial torque applied to the pelvis, incremental torque is added to power pelvic rotation."
What is your definition of "incremental" in this case? Make up some numbers for us - and run with it for a few years.
Can't make this stuff up…..
Michael Finney
New
"John Thomas" - you're right, that's when we were full throttle with "seems as if" observation. Sort of where you and your friends are stuck, right now.
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