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Post by imperfectgolfer on May 3, 2014 23:28:04 GMT -5
See this Jeffy forum thread - jeffygolf.com/showthread.php?1087-Manzella-strikes-backJeffy is trying to defend the Gracovetsky spine engine theory of locomotion. Jeffy posted this link to a Gracovetsky interview. www.somatics.de/Gracevetsky_Interview.pdfJeffy then made this statement-: " I have looked through McGill's research and the most substantive disagreement seems to be on the contribution of the lumbodorsal fascia in lifting heavy loads: Gracovetsky thinks it has a major role, McGill disagrees. The other aspect McGill criticizes is the notion of the spine acting like a rod when twisted. Neither of those criticisms falsify the fundamental premise of the spinal engine theory: that man evolved from creatures that used the spine as the "engine" of locomotion and the human spine supports that function, as opposed to being dead weight carried around by the legs.Jeffy is misinterpreting the critics of the spine engine theory. No rational critic is stating that human beings didn't evolve from creatures (eg. fish or snakes) that primarily use twisting motions of the spine to move about in space. However, over the millions of evolutionary years that human beings have being bipedal, they have primarily used their legs to move about in space. Any rotational motion of the spine and mid-upper torso is secondary to rotational motions of the pelvis that occur when walking/running and the spine is not the primary engine of locomotion. That's the major difference! One can still walk even if the spine and mid-upper torso cannot rotate in an unimpeded manner due to surgical or pathological spinal fusions procedures. For example, here is an image of a person who had total lumbar/thoracic spine fusion for severe scoliosis and that person can still walk (although non-optimally). Here is an image of a "bamboo spine" due to ankylosing spondylitis that produces total spinal rigidity. A person with severe ankylosing spondylitis can still walk - albeit without the necessary mid-upper torso rotary motions that allow for a well-balanced gait. No rational critic will dispute Gracovetsky's assertion that a person without legs can still rotate the pelvis and walk on his ischial tuberosities. However, that doesn't mean that the spine is the primary engine of locomotion. That may apply to snakes and eels, but it doesn't apply to bipedal human beings who have legs. What amazes me about Gracovetsky is his vague/imprecise assertions about human biomechanics. Consider this statement from his interview article. " The first role of the legs is to support the energy sources, which enable us to move at high speeds. However, rotation of the pelvis (as the pelvis rotates around a vertical axis when we walk) with muscles which draw the pelvis downwards leads to a problem of efficacy. This problem is resolved by using the earth's gravitational field as the site of intermediate storage, in which the muscle energy released by the legs with each step is temporarily stored and then recovered during the monopodal stance phase. This energy impulse then ascends up the leg and is filtered by the leg, so that it reaches the vertebral column with the appropriate phase and amplitude. The spine can therefore use this energy to mobilize each intervertebral joint, and to rotate each vertebra and the pelvis in an appropriate fashion." Talking about "using the earth's gravitational field as the site of energy storage" and talking about "energy impulses going up the leg and being filtered by the leg" is not a scientifically acceptable explanation in my intellectual world of human biomechanics. I can certainly understand how walking causes the pelvis to rotate (because of the motion of the femoral heads being transmitted to the acetabulum/pelvis) and how that pelvic motion causes the spine and mid-upper torso to also rotate "with the appropriate phase and amplitude", but that doesn't mean that the spine is producing the energy to "rotate the pelvis in an appropriate fashion" as Gracovetsky implies. Gracovetsky also implies that lordosis and lateral bend allows for an axial torque that allows a person without legs to ambulate on his ischial tuberosities. However, that doesn't mean his explanation is "anatomically correct" and I think that his wild theory about "interlocking gears" has no apparent scientific justification in terms of human anatomy. Jeffy also wrote-: " And, as you said, lumbar lordosis, lateral bend and left pelvic tilt are all right there in the swings of the elites, and lacking in everyone else's. Presumably, there is a good reason for that.". I am not surprised that Jeffy (a KM-disciple) would harbor such a black-and-white opinion. It is especially not surprising considering that he believes that Kelli Oride's and Michelle Wie's left wrist is moving towards extension between P7 and P7.2 in their DH-hand release action. Jeffy also derides me for always crticising KM, but he forgets his pathological hatred for BM and Mike Finney. At least, I am not so grossly uncivilized to post images like this image Jeffy posted in his forum. I frequently post targeted criticisms of KM's opinions re: golf swing biomechanics/mechanics, but I would never resort to such boorish behaviour. Jeff.
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Post by imperfectgolfer on May 4, 2014 21:44:40 GMT -5
When one reads the Gracovetsky interview carefully, you come across many foolish statements that are obviously wrongheaded. On page 1, he has a diagram showing a person standing erect with the legs together, and Gracovetsky states-: " If the leg cannot rotate the pelvis, then what rotates the pelvis ?? It has to be the spine." That's a BS claim! If one stands erect with the legs together and if there is a small degree of equal flex in the knees, then one simply has to straighten the right knee while increasingly flexing the left knee and that will cause the pelvis to rotate as shown in this next diagram. Straightening of the right knee will cause the right femoral head to move backwards and leftwards and that will cause the right acetabular socket to move likewise and that will cause the pelvis and lumbar spine to rotate. Then, one could simply flex the right knee while straightening the left knee to cause the pelvis to rotate in the opposite direction. Gracovetsky then foolishly argues as follows-: " I consider the spine to be the "primary" engine, in the etymological sense of the word. This primary engine, so obvious in our ancestors the fish, has not travelled towards the lower limbs over time, although its role has become more obscure and may appear to be secondary to the role of the lower limbs. However, this logic is faulty, as we are able to "walk" on our knees with relatively little adaptation, which demonstrates that our legs are not truly essential to human locomotion." This represents bizarre reasoning. I agree with his first claim that the spine was the primary engine of locomotion in an etymological sense (eg. first developing in fish and eels). But, then in the very next sentence, he states that the primary engine has not "travelled towards the lower limbs" (strange way of phrasing an evolutionary development) and he then immediately contradicts himself by stating that the primary engine may "appear to be secondary to the role of the lower limbs". Then, in the very next sentence he immediately backtracks and claims that the logic (of evolutionary development from the spine being the primary engine of locomotion to the legs being the primary engine of locomotion) is "faulty" because a person is able to walk on his knees. He is seemingly claiming that an ability to "walk" on one's knees proves "that our legs are not truly essential to human locomotion". That's ridiculously bizarre reasoning that only a KM-groupie could accept. The simple "fact" that a human being can ambulate on his knees doesn't prove that the legs are "not truly essential to human locomotion". It's a ridiculously stupid argument! Imagine watching a person walking on his hands in a circus act with his erect body-and-lower limbs vertically above his outstretched arms/hands. Would you then infer that it proves that "the legs are not truly essential to human locomotion" and would you therefore conclude that they are not the primary biological mechanism of human locomotion? Gracovetsky's reasoning becomes even more bizarre and irrational as he progresses in his argument. Gracovetsky stated-: " This therefore raises the question: how far can we cut the femur before affecting human locomotion. The answer is that the lower extremity can be completely removed without interfering with the primary movement of the pelvis. --- It is obviously preferable to have legs, but they only amplify the movements of the pelvis, and their functional role remains secondary". Only a KM-groupie could find this line-of-reasoning intellectually coherent. Gracovetsky is implying that the lower extremities are subservient to the "primary movement of the pelvis" (which he doesn't define and I presume that he is referring to rotation of the pelvis). He then seems to concede that "it is obviously preferable to have legs", but he then immediately (and irrationally) claims that their primary purpose is to "amplify the movements of the pelvis". What BS (irrational) reasoning! Human beings didn't develop lower extemities (from an evolutionary perspective) so that they could be of secondary service to pelvic motion - they developed legs so that they could walk! Jeff.
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Post by imperfectgolfer on May 5, 2014 9:40:39 GMT -5
More evidence of Gracovetsky's irrational reasoning.
In his interview, Gracovetsky stated-: "The presumed starting point (as it is only a hypothesis) is that primitive fish, 450 million years ago, moved in the same way as modern fish, i.e. by a lateral inflection movement of the spine. Fish which subsequently ventured onto dry land were faced with several problems,the first being to move by planting their fins into the mud by means of an alternating movement. This axial rotation movement combined with the lateral flexion movement resulted in the movements of flexion and extension. Thus, the simple need to move over small pebbles led our fish to invent flexion and extension movements. This same flexion-extension movement subsequently allowed galloping and the development of the lower limbs, as the para-axial muscles gradually moved outside of the abdominal cavity to become hamstring muscles, in order to increase the brute power available for locomotion."
Gracovetsky is hypothesising that when fish-like creatures moved onto land, that they needed to acquire limbs that are capable of flexion-extension motions so that they could go over obstacles like pebbles. That makes sense. One can reasonably argue that lizards/salamanders still use the spine as their primary engine of locomotion while they also use their short legs for flexion-extension motions. However, what about a horse? A horse has acquired 4 powerful legs that enable it to gallop at high speeds with very little motion of the spine. It would be ridiculous to believe that the spine engine is the primary engine of locomotion in a horse winning the Kentucky Derby. The same applies to an Olympic athlete winning a 100m race. It would be ridiculous to think that Usain Bolt's spine is the primary engine of locomotion when he wins a 100m sprint race!
Jeff.
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Post by imperfectgolfer on May 5, 2014 10:06:03 GMT -5
Jeffy wrongly claims that an elite golfer needs to have lordosis combined with lateral flexion in order to use the spine engine to power the golf swing. I think that he is 100% wrong! Consider an elite golfer - Gary Woodland. Here is a back view swing video. Here are capture images. Image 2 shows GW at the end-backswing position. Image 3 shows GW at the end of the hip-squaring phase (P5 position). During his early downswing (between P4 and P5) GW is primarily powering his downswing action with a counterclockwise rotation of his pelvis and lumbar spine (which moves in rotary synchrony with his pelvis). However, he doesn't have overt lordosis and he certainly doesn't have any lateral bend at that stage of his downswing. He only acquires lateral bend in his mid-late downswing (image 4 and 5). KM's Gracovetsky-derived idea that a golfer needs to have "lordosis + lateral bend" to engage the facet joints of the lumbar joints (like interlocking gears) has no basis in human biomechanical reality. The facet joints of the lumbar spine are always engaged - even if the natural lordosis is lessened and there is small degree of flexion-flattening of the lumbar spine. That is due to the physical structural design of the lumbar vertebra's cup-shaped facet joint. Note that the shape of the superior and inferior articular processes are such that they have ridges along the lateral border (mamillary processes) that impedes any rotary motion while allowing free motion within the sagittal plane of flexion-extension, and that "fact" applies even if the lumbar spine is lordotic or slightly flexed. The lumbar spine would have to be markedly flexed to disengage the facet joint's articulation between the superior and inferior articular processes. Jeff.
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Post by imperfectgolfer on May 5, 2014 22:19:48 GMT -5
I have suddenly understood why Gracovetsky came up with his idea of "lordosis + lateral bending" as the mechanism underlying his spine engine theory, and why it doesn't apply to a full golf swing. Here is the image from his interview paper. This person has no lower limbs and he shuffles about on his ischial tuberosities in a rotary-shifting manner when he locomotes. Because he has no pelvic girdle muscles (hip flexors/extensor muscles; hip adductor/abductor muscles; hip rotator muscles) he cannot power the rotational motion of his pelvis using the pelvic girdle muscles. He therefore has to use latero-flexion motions (what Gracovetsky calls "lateral bending" motions) of his mid-upper torso to torque his lumbar spine and pelvis in a rotary manner - see side-diagram. However, that situation doesn't apply to a non-handicapped golfer who has lower limbs. Consider a golfer at address. The pelvis is situated between the feet and the stable upper swing center/head and it can rotate freely in space. In that physically-handicapped person, who has no lower limbs, and whose pelvis rests directly on the ground, there is lot of frictional resistance to any rotary pelvic motion. However, in a "real life" golfer (pictured above) the pelvis is much more "free-floating" and there is very little resistance to its rotational motion in space. Think of a person using a hula hoop. It takes very little force for that person to rotate the pelvis (like a belly dancer) and that person doesn't need to use the the same axial torque force (lateral bending of the mid-upper torso) that is required by that physically-handicapped person without lower limbs. A non-handicapped golfer (as pictured above) can easily rotate the pelvis in the early downswing using the pelvic girdle muscles, and that rotary motion of the pelvis is made much easier if the knees change their degree of flex which causes the femoral heads to move about in space in such a manner that they can synergistically assist in the rotary motion of the pelvis. There is zero reason to believe that a golfer needs a combination of "lordosis + lateral bending" to induce a rotary motion of the pelvis in the full golf swing. A golfer may decide to use lateral bending in the mid-late downswing to ensure that the right shoulder moves downplane in an "appropriate" manner, and the degree of lateral bending depends on a golfer's chosen swingstyle. Keegan Bradley gets his right shoulder far more downplane than Phil Mickelson so he uses much more lateral bending motion in his mid-late downswing. Note that Hunter Mahan (image 4) and Keegan Bradley (image 5) have much more lateral bend than Phil Mickelson (image 3). Jeff.
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Post by imperfectgolfer on May 6, 2014 10:58:49 GMT -5
See this KM review article on "lateral bend" as it pertains to the spine engine theory - www.aroundhawaii.com/lifestyle/health_and_fitness/2010-04-spine-engine-swing-lateral-bend.htmlKM has drunken the Gracovetsky kool-aid and he wrongly believes that lateral bend (combined with lordosis) is necessary to induce a rotary motion of the pelvis in the early downswing. When does KM state that lateral bend must start? KM posted this image. This is what KM then states-: " Lateral bend, although it seems simple, is really quite complicated. Simplistically, it is just a side bending like the picture above. But add in that this must be done at a while you're at the top of your backswing with shoulders turned, while in the absence of downswing shoulder rotation (if for a brief moment), while your spine is being bent to the right, your shoulder is pulled down behind you while increasing lumbar lordosis (explained later) and while the rotator cuff muscles are externally rotating the arm. Now this seems very complicated. So when does lateral bending occur? It should start during transition." The bold-highlighted statement claims that lateral bending must start at the transition. However, that doesn't really happen in professional golfers. Note that there is no lateral bending of the mid-upper spine during Gary Woodland's early downswing (image 3 is at P5). Here is Jamie Sadlowski Here are capture images. Image 1 is at P4.5 - start of the transition; and image 2 is at P5 (end of the hip squaring phase). Note that there is no lateral bending of Jamie Sadlowski's mid-upper spine during his early downswing. KM is misinterpreting what is happening in professional golfers and he is also misrepresenting reality. KM posted this image of Ryo Ishikawa during the transition. KM wrongly claims that the curved red line represents lateral bending. However, that's obviously not true! Lateral bending refers to the spine and not the right lateral side of the torso, which can become more curved if a golfer develops dynamic torso-pelvic separation at the start of the downswing due to the pelvis rotating before the upper torso rotates or if the right clavicle becomes depressed. KM also wrote regarding that image-: " From this view, we can see that his shoulder has dropped AND his right side is arching away from the ball.". That biomechanical phenomenon is simply due to the fact that RI is depressing his right clavicle and dropping his right shoulder, and it doesn't imply any lateral bending of the mid-upper spine. Now, view this KM you-tube video demonstration. At 21-25 seconds, KM wrongly claims that the interfacet joints are not connected. However, here is a capture image from his video - captured at the 21 second time point (before KM applies lateral bend and lordosis). The red arrows show that the inferior articular processes are fully engaged with the superior articular processes of the vertebra directly below. I also cannot understand how KM can be applying lateral bend in his demonstration when he is not bending the mid-upper spine sideways. He is simply pulling the spine backwards. KM also makes some wild claims in his article on lordosis - www.aroundhawaii.com/lifestyle/health_and_fitness/2010-05-second-magical-key-to-the-spine-engine-lumbar-lordosis.htmlKM wildly claims-: " The key is in varying the amount of lumbar lordosis during the swing. Also we are combining the lateral bend with the lumbar lordosis to set the spine gears in place. Any disconnecting of the gears at any point prior to contact will produce an adverse swing reaction (most likely, a hip or shoulder stall) that will cause other problems to occur such as casting, flipping, lunging, jumping, etc. " I think that is wrongheaded to claim that "casting, flipping, lunging, jumping" is due to disengagement of the interfacet joints between the lumbar vertebra. KM posted this image of Tiger Woods. KM is wrongly claiming that the red curve represents lordosis. However, he is obviously wrong! Lordosis refers to the lumbar spine (which one cannot see in that image) and it refers to increased lumbar spine extension in the sagittal plane. That red curve is simply the side-bend of Tiger's left lateral mid-torso that is due to the differential degree of rotation of the upper torso (shoulders) relative to the lower torso (pelvis). KM then posted this image of Tom Agricola. KM then stated-: " Remember the left side of Tom Agricola’s backswing looked like a straight line? This is due to the lack of lumbar lordosis.He is wrong yet again! One cannot see his lumbar spine to assess his degree of lumbar spine lordosis in the sagittal plane. The "straightening" of the left side of his torso is simply due to the fact that he has only turned his upper torso (shoulders) as much as his lower torso (pelvis). I think that KM is out-of-his-depth when it comes to human biomechanics, and it is not surprising that he harbors this wild belief when he stated-: " Another contributor to spine compression and stiffness can occur from dehydration. Yes, that’s right. Dehydration from lack of drinking water (no, soda, coffee, tea or adult beverages don’t count as water) can also contribute to lack of spinal mobility as well as non-optimal health.Jeff.
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Post by imperfectgolfer on May 7, 2014 11:39:41 GMT -5
More wrongheaded KM comments follows. KM posted this image in his lordosis article. KM then stated-: " Just before impact, a transformation begins to occur. The right side retains lordosis while the left side of the body begins to lose lordosis. This is absolutely critical!
The right side must retain the lordosis so that the gears remain connected and rotation can continue through the impact zone. But what is really interesting is what’s happening to the left side of the body." Lordosis is defined as increased extension (hyperextension) of the lumbar spine in the sagittal plane and therefore it cannot be different on the left compared to the right. KM is obviously referring to the "fact" that the right side of the mid-upper torso is shortened/compressed while the left side of the mid-upper torso is extended/expanded and that is due to the lateral bend that develops in the mid-late downswing. Lateral bend does not really affect the upper lumbar spine much, and it primarily affects the thoracic spine, and therefore it doesn't affect the engagement between the superior and inferior articular processes of the lumbar vertebra. Those lumbar interfacet joints are always engaged throughout the entire downswing and followthrough, which explains why the pelvic sacrum and lumbar spine always move in perfect unison throughout the downswing and followthrough. I have never seen the lumbar spine rotate less/more than the pelvic sacrum in any professional golfer during the downswing/followthrough time period from P4 to P7.5+. KM then also wrote-: " In the impact zone, when the powerful leg and hip extensors are firing, the PLS is the “primary force transmission mechanism” according to Gracovetsky. The PLS connection from the hip bone to the spinous processes (facets) allow the direct flow of force to pulse the spine engine to rotate faster via an elastic recoil that is more powerful than just muscular force." As Stuart McGill stated in his interview, there is no evidence that there is any elastic recoil function as Gracovetsky implies and as KM wrongly infers in this next swing video. KM shows that the flexible rod "snaps" back after it is released from a wound-up condition. He claims that this happens in the human spine. I think that's a BS belief! However, I certainly can imagine that a "force" is generated when the upper torso rotates faster than the lower torso through impact and that "force" is passively transmitted down the spine and paraspinal tissue to cause the lumbar spine/pelvis unit to rotate faster. However, that doesn't represent an elastic recoil force! Also, the spine is not a rigid rod and the thoracic spine is capable of "spiralling" because of the anatomical design of the interfacet joints of the thoracic vertebrae. The superior/inferior articular facet surfaces are flat, so the thoracic articular processes can slide-rotate over each other at the level of the interfacet joints. That allows the thoracic spine to lateral bend, forward bend and also rotate in a spiral fashion. However, that doesn't mean that the thoracic vertebra (and associated paraspinal ligaments) are capable of an elastic recoil action. The individual thoracic vertebra slide-rotate in response to active muscular forces or passive mechanical torque forces transmitted via the paraspinal ligaments/muscles. Gracovetksy's "elastic recoil" theory has no validity from the perspective of noted spinal biomechanists - like Stuart McGill. Stuart McGill's CV - www.ahs.uwaterloo.ca/kin/documents/McGill%20Full%20Sept%202011.pdfBy the way, I discovered that Stuart McGill formally responded to Serge Garcovetsky regarding their contrary opinions re: the dorso-lumbar fascia theory controversy. See these two letters. McGill, S.M., and Norman, R.W. Response to the critique of S. Gracovetsky, Spine, 15(11): 1239-1240, 1990. McGill, S.M., and Norman, R.M. Response to the critique of Dr. S. Gracovetsky of Potential of Lumbordorsal Fascia Forces to Generate Back Extension Moments During Squat Lifts. J. Biomed. Engng. 11: 172-175, 1989 Here is a link to the letter written by Stuart McGill - journals.lww.com/spinejournal/Citation/1990/11010/Letters.29.aspxJeff.
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Post by imperfectgolfer on May 7, 2014 23:34:26 GMT -5
Here is yet more commentary that demonstrates that Gracovetsky's "lordosis + lateral bend" theory is inaccurate. Consider yet again this image from the Gracovetsky interview. Note that there is actually no lordosis of the lumbar spine in that diagram showing lateral bend. The lower part of the spine (lumbar spine) in that diagram is actually flat and there is only side-bend in that image (roughly at the level of the lower thoracic spine). Both Gracovetsky and KM are wrongly labeling that side-bend (that is oriented leftwards) as being lordosis, and Gracovetsky/KM are wrongly inferring that it causes the interfacet joints to interlock (like interlocking gear cogs) on the concave-appearing left side. However, if you look at that person in the image, note that he has no lordosis (hyperextension) of his lumbar spine, and note that he has only minimal side-tilt of his spine at the level of the lower thoracic spine. That side-tilt of the lower thoracic spine cannot be causing interlocking of the interfacet joints of the lower thoracic spine (like interlocking cog gears) because the facet joints in the thoracic vertebra are flat (and only interlock like shingles on a roof). Now that I have seen the "real life" image of the person on which SG's "spine engine" theory is based, I am increasingly certain that his "spine engine" theory is irrational. Here are images showing lordosis. and and Note that the medical condition of lordosis represents an exaggerated degree of lordotic curvacture of the lumbar spine in the sagittal plane. Some people refer to this condition as hyperlordosis. Gracovetsky/KM are using the term "lordosis" incorrectly and KM is wrongly using the term "lordosis" to refer to the concave side-bend of the mid-torso created on the compressed side when a person acquires lateral bend of the spine. That side-bend doesn't affect the lumbar spine (because the lumbar vertebra have a mamillary process along the lateral border of the superior articular interfacet joint process that impedes side-bending) and it mainly affects the lower thoracic spine. Here is Jamie Sadlowski exhibiting the first signs of lateral bend, which happens in his mid-downswing time period. I have traced the likely position of his spine with its small degree of lateral bend (curved red line). The short blue line represents the upper limit of the lumbar spine. Note that his lateral bend is happening at the level of his lower thoracic spine. Here is a back-view photo of Hunter Mahan from KM's article on lateral bend. Note that the lateral bend only involves the thoracic spine (which have flat interfacet joints that are incapable of interlocking), and not the lumbar spine. One can also clearly see that Hunter's lumbar spine is flat and not overtly lordotic. Jeff.
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Post by imperfectgolfer on May 8, 2014 9:55:32 GMT -5
Here is further evidence that KM is misinterpreting, and misrepresenting, reality. Consider this image from his article on lateral bend. Consider what KM stated regarding this image-: " From this view, we can see that his shoulder has dropped AND his right side is arching away from the ball." KM shows that the right shoulder is dropping and he wrongly concludes that it is due to arching (lateral bending of the spine). However, there is a more rational biomechanical explanation for "what is causing the right shoulder to drop" in the early downswing. Consider Jamie Sadlowski's early downswing action - between P4 and P5.3. Note how much JS's right shoulder has dropped between image 1 and image 3. What is causing it to drop? I believe that the answer is obvious. JS's right scapula is fully retracted at the P4 position, and during the early downswing he starts to protract his right scapula and slide it downwards and forwards across the back of his right upper torso. During the time period of that right scapula motion, the right clavicle becomes depressed at its lateral end. As the inferior angle of the scapula moves laterally, it will give the impression of there being a more concave curve at the outer border of the right mid-upper torso. However, that doesn't mean that lateral bend of the spine is responsible for that concave-curved appearance of the outer border of the right mid-torso - note that JS's head had not moved rightwards and note that the spine only develops a small amount of lateral bend between P5 and P5.3. Note that the small degree of lateral bend of the spine (which doesn't develop during the transition) isn't due to rightwards movement of the head/cervical spine, but it is due to rightwards movement of the pelvic sacrum (and associated lumbar spine) that happens during the hip squaring phase of the early downswing. A secondary factor that increases the size of the bulge seen on the right side (just below the right shoulder socket) during the early downswing is the fact that he is actively adducting the right humerus during this time period, which requires the active contraction of the right shoulder girdle muscles. As the right shoulder girdle muscles become more contracted, they become more bunched-up (rather than stretched-out) and that bunched-up condition of the right shoulder girdle muscles contributes to the concave appearance of the right lateral border of the right mid-torso (especially considering the fact that the inferior angle of the scapula has moved laterally during this time period). Jeff.
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Post by imperfectgolfer on May 9, 2014 11:34:12 GMT -5
I have been examining back view videos of many professional golfers to determine whether any of them acquire lateral bend during their transition (as KM asserts is necessary to activate the spinal engine). None of them do! They all start their downswing with a pelvic shift-rotation motion (left hip clearing action ala Hogan) where they pull-rotate their left buttock back against the tush line while they rotate their pelvis/sacrum counterclockwise. They only develop lateral bend in their mid-downswing, and not during their early downswing. None of them increase their natural degree of lumbar lordosis in the sagittal plane during their downswing's pelvic motion. Consider a few examples. Example 1 - Dustin Johnson Here are capture images. Image 1 shows DJ at the P4 position. Image 2 shows DJ's transition - note that he is rotating his pelvis, but he has no lateral bend. Image 3 shows DJ at the end of the early downswing. He has a small degree of right lateral bend - but that is not due to any lateral side-bending of the mid-upper spine to the right, but it is due to the "fact" that his pelvic sacrum has rotated rightwards and it has moved closer to his head position, thereby shortening the distance between his head and sacrum. Another biomechanical factor that shortens the distance between the head and the sacrum is the fact that DJ loses his arch-extension maneuver (which is present at his end-backswing position) as he starts to rotate his upper torso (shoulders) counterclockwise during his early downswing. Image 4 shows DJ in his mid-downswing where he definitely has lateral bend. Note that his pelvis is now very open and he is driving his right shoulder downplane, and that requires lateral bend. However, the lateral bend is not happening before his pelvis moves in the early downswing, and it is not the causal agent of his rotary pelvic motion. Note that he has a natural degree of lumbar lordosis in the sagittal plane, and that it doesn't increase in degree during his early downswing. Example 2 - Rory McIlroy. Here are capture images. Image 1 is at P4, and images 2,3 and 4 represent the early downswing. Note the absence of lateral bend and note that there is no change in his natural degree of lordosis in the sagittal plane during his early downswing action. Here are those same images presented as an animated gif. One can clearly see how RM is shift-rotating his pelvis and squaring his pelvis by the P5 position - but without any lateral bend. Example 3 - Hunter Mahan. Here are capture images. Image 1 is at P4, and images 2,3 and 4 show his early downswing action. Note how he rotates his pelvis counterclockwise without any preliminary lateral bend. The small degree of lateral bend that he acquires by the P5 position is due to the the counterlockwise rotation of his pelvic sacrum that brings his pelvic scarum closer to his head. Here are those same images presented as an animated gif. Note how HM rotates his pelvis counterclockwise during his early downswing without having to first acquire any lateral bend of his mid-upper spine. Note that he has a natural degree of lordosis of his lumbar spine in the sagittal plane, and that it doesn't change in degree during his early downswing. Jeff.
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Post by imperfectgolfer on May 11, 2014 17:27:57 GMT -5
See this new Jeffy-originated thread - jeffygolf.com/showthread.php?1100-Hey-Mike-Finney-the-votes-are-in!!! Jeffy wrote-: " Thanks to TPI and a random sample of four players, including two major champions, we have 3D quantitative confirmation that right side lateral bend is directly correlated with increased rotation of the pelvis and thorax during the downswing and at impact, as well as "sustaining" rotational velocity from its peak until impact!!! Also, right side lateral bend, or "locking the facets", is directly correlated with simultaneous peaking of the thorax and pelvic angular velocities!!! Dr. Gracovetsky and the spine engine rule!!!
Read all about it here:
jeffygolf.com/showthread.php?...h-this-picture
I love science!!!
Jeffy lives in a virtual world where he simply declares the existence of "facts" (based on a loose correlation) that are unsupported by science. He has one thing is common with MF - they both claim that their personal beliefs are supported by science, even though that's not true! They are like two peas in a pod! They simply declare themselves as being the "winner" even though their "beliefs" have very little "real life" biomechanical support. There is ZERO evidence that right lateral bend, which only develops in the mid-late downswing, is associated with "locked facets". Also, KM claims that right lateral bend has to develop in the transition to drive the spine engine, and pro golfers do not develop right lateral bend in the early downswing. Also, the right lateral bend only occurs in the lower thoracic spine area ( and the thoracic vertebrae are incapable of being "locked"), and it doesn't affect the lumbar spine which never acquires lateral bend in a pro golfer's downswing. Here is the TPI graph posted by Jeffy of Gray Woodland's swing. Note that there is spinal bend towards the target at P4, which fits in with the "fact" that a pro golfer often has arch-extension of the mid-upper thoracic spine if he uses a rightwards-centralised backswing action (like Gary Woodland) that keeps the head relatively centralised during the backswing action. Note that during the transition, the degree of spinal bend is less than ZERO, which proves that a pro golfer doesn't develop right lateral bend during the transitional period - as KM wrongly claims. That proves that the lateral bend cannot be powering the early downswing's pelvic rotational motion, which is what the "spine engine" theory falsely claims. Here is the back view images of Gary Woodland that I previously posted. Image 3 shows that GW doesn't acquire any significant right lateral bend in his early downswing - as that TPI graphs demonstrates. Jeff.
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Post by imperfectgolfer on May 12, 2014 21:27:59 GMT -5
MF wrote the following in the BM-forum thread-: " The full retard that is Jeff Martin says:
"Thanks to TPI and a random sample of four players, including two major champions, we have 3D quantitative confirmation that right side lateral bend is directly correlated with increased rotation of the pelvis and thorax during the downswing and at impact, as well as "sustaining" rotational velocity from its peak until impact!!! Also, right side lateral bend, or "locking the facets", is directly correlated with simultaneous peaking of the thorax and pelvic angular velocities!!! Dr. Gracovetsky and the spine engine rule!!!"
So, you have proven the spinal engine theory by looking at four random samples? Surely you're not that stupid…..right?
And now "lateral bend" equals "locking facets" ? You're a straight up moron…..you're out of your league.I rarely agree with MF, but he is right in this instance. It is ridiculous for Jeffy to claim that lateral bend (which happens in the mid-late downswing) proves that "locked facets" exist on the compressed side of the lateral bend. He has zero evidence of that "fact", and he is simply asserting his personal opinion based on an 'a priori' belief that there is such a biomechanical phenomenon as "locked facets". Also, correlation isn't equal to causation. The fact that lateral bend peaks at the same time as the peak rotational speeds of the pelvis/upper torso doesn't imply that lateral bend is responsible for causing the rotational velocities of the lower/upper torso to peak at that time of the downswing. Lateral bend is acquired in a golfer in the mid-late downswing if he wants to get his right shoulder more downplane and if he wants to get his hands/clubshaft on a shallow plane at impact. Phil Mickelson's clubshaft is on the TSP at impact, and his right shoulder doesn't get far downplane (when compared to Keegan Bradley) , so he therefore doesn't use much lateral bend. However, he has excellent rotation of his pelvis and upper torso during his downswing action. The timing of his peak upper torso rotational velocity will be very different to Keegan Bradley's because he has near square shoulders at impact while KB has much more open shoulders at impact. Also a golfer who uses a "no-roll hand release action + CP-arm release action" is going to have a very different pattern of peak pelvic/shoulder rotational motions compared to a golfer who uses a "full-roll hand release action + CF-arm release action". Jeffy is oblivious of these different patterns of arm/hand release actions. Jeff.
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Post by miuradude on Jun 14, 2014 7:44:30 GMT -5
Jeff, I'm not trying to be antagonistic for no reason or anything like that, but I have embraced Kelvin's philosophy this golf season, and I am now striking the ball better than I ever have (been playing for 20+ years). My handicap index has already gone down a stroke or so this year (6.3 to 5.2), and well, let's face it, my handicap index going down is the only FACT that is relevant to me.
So while your obvious obsession with proving Kelvin wrong is readily apparent, what is also true is that Kelvin's methods have helped me and others enjoy this game in ways we haven't before. And that is also FACT.
Deke
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Post by imperfectgolfer on Jun 14, 2014 8:58:48 GMT -5
Deke,
It is totally irrelevant whether you like KM's golf instructional ideas or whether your golf swing has improved using his golf instructional ideas. This forum NEVER discusses an individual's golfer's personal experiences when following any golf instructor's teaching principles and it only discusses the intellectual and "real life" validity of any person's ideas re: golf swing biomechanics/mechanics. KM's "spine engine" ideas have no intellectual (biomechanical) validity and they don't correspond to the "real life" reality of pro golfers swings (like Bubba Watson's swing).
Jeff.
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Post by grantrhooper on Jun 16, 2014 17:07:48 GMT -5
Jeff, You may be right that personal testimonies do not make a teaching right or wrong, in reality... Wrong teachers can accidentally produce good results and vice versa... based on many variables as you have pointed out. I certainly do not consider it scholarly to use testimonies as the end all be all of whether a teaching is right or not.... Under a controlled setting, it would matter though. If you sent 100 students to kelvin and he taught the same thing to all of them, and they all had the athletic ability to perform these moves, listened to him, and followed instruction... and they all got better and more powerful. That would indeed matter. The reality lies somewhere in between the two in this case. It would be ridiculous to use a couple before and after swings to justify an entire theory. But it is equally ridiculous and entirely bias to totally disregard a plethora of swing changes, that are not present among the followers of any other teacher in the golf world today, or in the history of civilization, anywhere. As for your posts above, I actually don't disagree. I have always felt Rory's swing was different and that he did not use a lot of lateral bend, even though you see the right shoulder lower slightly in transition. Also agree with you on hunter mahan and gary woodland. My personal swing thoughts slightly vary in that, I think its perfectly acceptable to add lateral bend AFTER left pelvic tilt and weight shift. I actually think doing it this way can be easier for some people. I also think that going over the top and then coming under like Carl Petterson is another way to do it, depending on who you are and that every swing should be tailored to the individual. And believe it or not, I also agree with you on the Lordosis. I think that good golfers are very flexible and their torso and spine is twisted up like a pretzel, especially from a down the line view but slanted 45 degrees towards a rear view... a sort of "quarter view". It's hard to tell exactly whats going on with the scapula sticking out, extension in some cases, anterior pelvic tilt, moving towards left pelvic tilt in some cases. At this point in the swing with the way everything is stretched out, we have moved from the equivalent of 2d to 3d, and therefore, trying to make correct observations becomes more difficult. I am actually of the thought that it is acceptable to maintain anterior pelvic tilt throughout the swing, rather than increase it. I don't think Kelvin is wrong, but I think that his articles use limited case studies and that some players do slight variations. Also, some of his articles are old and out-dated. For instance in the tiger transition article from like 6 years ago, he talks about pushing off the right leg in transition which he certainly does not prescribe anymore. Anyway, I think that in some players, what we are actually seeing, rather than "increasing lordosis" is the shoulders completing their turn, with the scapula sticking out and, in some cases, the spine even tilting slightly backwards at the end of the swing, causing the left shoulder to go down (that or "left lateral bend"), all while the pelvis stays in APT and the sacrum moves towards the target (and in a circle throughout the swing)... but in the cases of these larger elongated swings, the right leg straightens and pushes back, while APT is maintained, and to make the swing longer, the left heel unweights and then the combined appearance of the left foot re-planting and the pelvis going downward, all while the left scapula protracts and the right scapula remains very visable...this all creates a look of the shoulders moving back while the pelvis moves forward. A stretching in two different directions, per say, between the upper and lower body. Some people call it an X-factor increase, but obviously there is a lot more going on here. I do think APT is increased in some cases, which is what Kelvin is referring to with regards to increasing Lordosis... players who extend in their backswing and then squat down hard... But I also think some players just mainting APT. What we wouldn't want to happen is to PPT and come out of our posture. What do you think is happening in this swing of Steve, who is a (plus) 2.8 handicap player that swings 115-120 mph? www.youtube.com/watch?v=vXU5Z8qnsNo
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