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Post by dubiousgolfer on Oct 25, 2018 11:25:19 GMT -5
Dr Mann -sorry for the number of questions I've recently raised as I am sure you are very busy
If on average LPGA tour are 100 degrees/sec faster for pelvis and ribcage than PGA Tour players, why can't they hit the ball further (for a swinging action)? If LPGA golfers were using active pivots to release PA4 , wouldn't their higher ribcage rotation equate to a higher clubhead speed just before CF forces induce release?
Wouldn't a quicker ribcage rotation mean that the shoulder sockets are rotating faster and pulling the left arm/hand/club faster from P4 - P5.3 (ie. just before a random CF induced release)?
Could a possible explanation be that the male PGA players are able to create more initial clubhead speed (just before a CF induced release) by additionally (as well as their PIVOT) using their stronger lead arm shoulder girdle muscles and right arm adductor muscles between P4-P5.3 (just before a CF induced random release)?
DG
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Post by imperfectgolfer on Oct 25, 2018 23:14:43 GMT -5
Dr Mann -sorry for the number of questions I've recently raised as I am sure you are very busy If on average LPGA tour are 100 degrees/sec faster for pelvis and ribcage than PGA Tour players, why can't they hit the ball further (for a swinging action)? If LPGA golfers were using active pivots to release PA4 , wouldn't their higher ribcage rotation equate to a higher clubhead speed just before CF forces induce release? Wouldn't a quicker ribcage rotation mean that the shoulder sockets are rotating faster and pulling the left arm/hand/club faster from P4 - P5.3 (ie. just before a random CF induced release)? Could a possible explanation be that the male PGA players are able to create more initial clubhead speed (just before a CF induced release) by additionally (as well as their PIVOT) using their stronger lead arm shoulder girdle muscles and right arm adductor muscles between P4-P5.3 (just before a CF induced random release)? DG If female LPGA golfers can rotate their pelvis and left shoulder socket faster than men between P4 and P5.5, then they should be hitting the ball farther than men - presuming that they are both using a TGM swinging action. Men may be physically more muscular than women and they may be able to generate more power using their left shoulder girdle muscles that pull the left arm downwards and their right shoulder girdle muscles that adduct the right arm between P4 and P5.5, but I cannot understand how that could significantly increase swing power because one cannot be using those actions independent of the pivot if one is using a TGM swinging technique. I would have to revise my theories on swing power generation in professional golfers if there is sound "evidence" to support a "belief" that women have a faster pivot action than men. Do you have access to any "evidence" on this issue? Jeff.
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Post by dubiousgolfer on Oct 26, 2018 7:20:22 GMT -5
Dr Mann This is what I've seen in the last few days on Golfwrx from Dan Carraher and Soloman1 (a director of 3D Company who works closely with Phil Cheetham). Yes it would be nice to see the statistics but I've tried searching for the information without success. Although Carraher only mentions hips , not ribcage unlike Soloman. www.golfwrx.com/forums/topic/1704792-the-myth-of-timing-vs-non-timing-based-swings-stable-club-face-etc/page__st__180------------------------------------- Soloman1 :Posted Yesterday, 08:01 AM With the driver, it’s been measured that men pros use hands more to contribute to clubhead speed than women pros use. The other percentages are from legs, core, shoulder motion, etc., with women using more power from the legs. Women pros, on average, rotate pelvis and ribcage faster that men pros. If rotating faster makes you hit the ball farther, why don’t women pros hit it as far as men pros? The different is all in the hands. I suppose the takeaway from that is if you want to hit it like a girl, use a “pivot driven swing” (whatever that means) with less hands. And I mean no disrespect toward women golfers with that. The genders are built differently. ---------------- Dan Carraher It’s 100% true. Easy to find the data. TPI has posted some of it publicly. Average LPGA Tour player has significantly higher rotation speed with hips than the guys do. PS Soloman is president of a 3D company that sells and measures one of the popular 3D systems and has worked directly with Phil Cheethum extensively --------------- Soloman1 You aren’t alone about what you perceive to see. As we’ve been able to capture more information with higher speed equipment, we’re able to see the things in 3D that we can’t possibly see with our eyes or slower speed cameras or older technology. The brightest minds in golf take the new information and apply it, changing their old held beliefs that were not based on any data at all. It’s surprising also how the modern professional swing has changed in such a short period of time. I’ll give you an example. People used to think that there was some ideal rotational sequence that most all professionals and elite amateurs have in common. I have a presentation called “Pro or no.” It’s a series of sequences that I have teaching pros look at and simply write if it’s a pro sequence or not. No one comes close to getting them right now. It’s self graded... Some 20 handicaps have a more “ideal looking sequence” and some top pros have sequences that the pros think is a hacker. When you boil down the data, there is no ideal pattern or swing or swing method. People are different and have different bodies, tendencies, traits, strengths and weaknesses. Trying to pigeon hole people into doing one method doesn’t work. (Edited: should say doesn’t work as well) If there was one universal best way, every tour pro would be doing it. Edited: the “average” for LPGA tour is 100 degrees/sec faster for pelvis and ribcage than PGA Tour. That doesn’t mean that player A is faster than player B. ----------- Forth Worth Pro The issue most people have in understanding this is yes women's hips reach a higher top end speed because they don't properly accelerate the next segment very well to decelerate the pelvis. I think a better measure would be look at longer male PGA tour players versus shorter male PGA tour players. Would most likely be a higher correlation in hip speed to club head speed. At the end of the day, it's about how can you create force and torque and speed aids the application of force. ----------------- Soloman1 Perhaps it’s better said that they cannot, rather than don’t, accelerate the arms, hands, clubhead at a ratio better matching the pelvis and core speed. -------------------------------- Unsure what FWP/Soloman1 are saying but I think they are inferring that the female player's arms and hands are not being rotated quickly enough in the downswing. Therefore the tension created in the clubshaft is not pulling enough on the LPGA arms (and therefore the shoulder socket/ribcage) to slow them down. This is why their ribcage is moving on average faster than the males. If the above is correct , then maybe the kinetic sequence for the downswing might start with the arms first just before the upper torso pivots (ie. reactive pivot) or The pivot is active , but then the male players arms/hands become more 'independently involved' (than the female players) in the early downswing to create clubhead speed , that creates more tension in the clubshaft that then pulls/slows the lead arm/shoulder socket . DG
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Post by imperfectgolfer on Oct 26, 2018 9:27:41 GMT -5
Dr Mann This is what I've seen in the last few days on Golfwrx from Dan Carraher and Soloman1 (a director of 3D Company who works closely with Phil Cheetham). Yes it would be nice to see the statistics but I've tried searching for the information without success. Although Carraher only mentions hips , not ribcage unlike Soloman. www.golfwrx.com/forums/topic/1704792-the-myth-of-timing-vs-non-timing-based-swings-stable-club-face-etc/page__st__180------------------------------------- Soloman1 :Posted Yesterday, 08:01 AM With the driver, it’s been measured that men pros use hands more to contribute to clubhead speed than women pros use. The other percentages are from legs, core, shoulder motion, etc., with women using more power from the legs. Women pros, on average, rotate pelvis and ribcage faster that men pros. If rotating faster makes you hit the ball farther, why don’t women pros hit it as far as men pros? The different is all in the hands. I suppose the takeaway from that is if you want to hit it like a girl, use a “pivot driven swing” (whatever that means) with less hands. And I mean no disrespect toward women golfers with that. The genders are built differently. ---------------- Dan Carraher It’s 100% true. Easy to find the data. TPI has posted some of it publicly. Average LPGA Tour player has significantly higher rotation speed with hips than the guys do. PS Soloman is president of a 3D company that sells and measures one of the popular 3D systems and has worked directly with Phil Cheethum extensively --------------- Soloman1 You aren’t alone about what you perceive to see. As we’ve been able to capture more information with higher speed equipment, we’re able to see the things in 3D that we can’t possibly see with our eyes or slower speed cameras or older technology. The brightest minds in golf take the new information and apply it, changing their old held beliefs that were not based on any data at all. It’s surprising also how the modern professional swing has changed in such a short period of time. I’ll give you an example. People used to think that there was some ideal rotational sequence that most all professionals and elite amateurs have in common. I have a presentation called “Pro or no.” It’s a series of sequences that I have teaching pros look at and simply write if it’s a pro sequence or not. No one comes close to getting them right now. It’s self graded... Some 20 handicaps have a more “ideal looking sequence” and some top pros have sequences that the pros think is a hacker. When you boil down the data, there is no ideal pattern or swing or swing method. People are different and have different bodies, tendencies, traits, strengths and weaknesses. Trying to pigeon hole people into doing one method doesn’t work. (Edited: should say doesn’t work as well) If there was one universal best way, every tour pro would be doing it. Edited: the “average” for LPGA tour is 100 degrees/sec faster for pelvis and ribcage than PGA Tour. That doesn’t mean that player A is faster than player B. ----------- Forth Worth Pro The issue most people have in understanding this is yes women's hips reach a higher top end speed because they don't properly accelerate the next segment very well to decelerate the pelvis. I think a better measure would be look at longer male PGA tour players versus shorter male PGA tour players. Would most likely be a higher correlation in hip speed to club head speed. At the end of the day, it's about how can you create force and torque and speed aids the application of force. ----------------- Soloman1 Perhaps it’s better said that they cannot, rather than don’t, accelerate the arms, hands, clubhead at a ratio better matching the pelvis and core speed. -------------------------------- Unsure what FWP/Soloman1 are saying but I think they are inferring that the female player's arms and hands are not being rotated quickly enough in the downswing. Therefore the tension created in the clubshaft is not pulling enough on the LPGA arms (and therefore the shoulder socket/ribcage) to slow them down. This is why their ribcage is moving on average faster than the males. If the above is correct , then maybe the kinetic sequence for the downswing might start with the arms first just before the upper torso pivots (ie. reactive pivot) or The pivot is active , but then the male players arms/hands become more 'independently involved' (than the female players) in the early downswing to create clubhead speed , that creates more tension in the clubshaft that then pulls/slows the lead arm/shoulder socket . DG Solomon stated-: " With the driver, it’s been measured that men pros use hands more to contribute to clubhead speed than women pros use. The other percentages are from legs, core, shoulder motion, etc., with women using more power from the legs." What does it mean to state that male pros use their hands more to contribute to clubhead speed? What are they actually doing with their hands to generate clubhead speed? How does he calculate how much percentage of clubhead speed comes from the legs? What are the legs doing to contribute to clubhead speed?
How does he calculate what percentage of clubhead speed comes from the core and from shoulder motion? How does he even differentiate between core motion and shoulder motion? Pardon my scepticism - but I would need a lot of further information before I take Solomon's opinions seriously. Also, why is he measuring rib cage speed rather than the speed of motion of the left shoulder socket? I can readily imagine a female LPGA golfer twisting the thoracic spine and rib cage fast without it necessarily causing the two shoulder sockets to move faster? When I refer to the term "upper torso rotation" I am usually referring to the motion of that segment of the upper torso that includes the two shoulder sockets. Many female golfers have very flexible spines and I can imagine them rotating their pelvis and lumbar spine and their lower/mid-thoracic spine very fast without a concomitantly fast rotation of their shoulder sockets. I am interested in the speed of rotation of the two shoulder sockets between P4 and P5 (which is my chief measure of the speed of the pivot action) and I am sceptical that female LPGA golfers are rotating them faster than Dustin Johnson, Justin Thomas or Rory McIlroy. Jeff.
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Post by dubiousgolfer on Oct 26, 2018 9:37:56 GMT -5
Dr Mann - you have made some very good points . So it all boils down to the method they are using to capture/measure this data taking into account all the issues you mentioned above. Pity I am still banned from their forum otherwise I would have raised questions relating to your points of issue.
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Post by dubiousgolfer on Oct 27, 2018 8:21:20 GMT -5
Dr Mann You've said above "When I refer to the term "upper torso rotation" I am usually referring to the motion of that segment of the upper torso that includes the two shoulder sockets." So are you referring to any muscles that move the shoulder socket in space independent of any 'rolling' motion of the humerus head in that same socket? So for example, I have been reading this article below about muscle activity in the golf swing (which seems to be an amalgamation of different articles) bjsm.bmj.com/content/39/11/799I've then tried to understand the movements caused by the various main muscles they stated as being actively used in the 'Forward Swing ' and 'Acceleration' phases (which I've summarised below). From what I read below , there seems to be lots of muscle activity involved in moving the scapular in the upper body while secondary rotation of the lower/upper spine cause by the rotation of the pelvis. So doesn't it make sense that in males, the muscles involved in moving the scapular (and therefore the shoulder joint) in space are major generators of power than just the rotation of the spine/ribcage (and on average more powerful than female golfers)? So for clarification, when you mention upper body rotation, you don't just mean the rotational aspect of the shoulder socket caused 'only' by the rotation of the thoracic section of the spine, but also all the muscles that move the scapula too? DG ------------------- Forward swing The forward swing starts at the top of swing and ends when the club is horizontal to the ground (early part of down swing). The most active muscle in the upper body during this phase in the upper body on the left side is the rhomboid (68% MMT) and middle trapezuis (51% MMT). On the right side, the most active muscles are the pectoralis major (64% MMT) and upper serratus (58% MMT). The most active muscle during the forward swing phase in the lower body are the upper and lower gluteus maximus (100% MMT and 98% MM) on the right side along with the biceps femoris (78% MMT). On the left side, the most active muscles are the vastus lateralis (88% MMT) and the adductor magnus (63% MMT). Upper Body Left Side -Rhomboid 68% - Moves the Scapula (and therefore the shoulder socket) Left Side Middle Trapezius 51% - Moves the Scapula (and therefore the shoulder socket) Right Side :Pectoralis major 64%- adduction and internal rotation of the humerus Right Side : Upper Serratus 58% - Moves the Scapula (and therefore the shoulder socket) Lower Body Right Side : Upper and Lower Gluteus Maximus - 100% and 98% - extensor of the thigh on the pelvis, extensor of the pelvis on the thigh (and retroversion), Lateral rotator of the thigh. Right Side : Biceps femoris 78% - Flex the leg at the knee, laterally rotate the knee from the flexed position, extends the thigh at the hip. Left Side : Vastus Lateralis 88% -Knee extension Left Side : Adductor Magnus 63% -adductor of the thigh, hip extension, external rotation of knee as the thigh adducts. Acceleration The acceleration phase starts from the horizontal club to the impact of the ball (late part of down swing). This phase of the swing sees the pectoralis major muscle bilaterally being the most active muscle (93% MMT bilaterally) in the upper body. On the right side, the second most active muscle is the upper serratus anterior (69% MMT). On the left side, the levator scapulae is the second most active muscle (62% MMT). In the lower body, the acceleration phase sees the left biceps femoris (83% MMT) being the most active muscle with the left upper and lower gluteus maximus, along with the vastus lateralis being the second most active muscles (58% MMT). On the right side, the abdominal oblique (59% MMT) is the most active muscle, followed by the gluteus medius (51% MMT). Upper Body Right Side: Pectoralis Major 93% - adduction and internal rotation of the humerus Right Side : Upper Serratus Anterior 69% - Moves the Scapula (and therefore the shoulder socket) Left Side: Pectoralis Major 93% - adduction and internal rotation of the humerus Left Side: Levator Scapulae 62% - Levitates the Scapula (and therefore shoulder socket) Lower Body Right Side: Abdominal Oblique 59% - spinal rotation, anterior flexion of the spinal column, lateral flexion of spinal column. Right Side: Gluteus Medius 51% -One of the most powerful abductors and internal rotators of the hip (flexion and internal rotation, extension and external rotation) Left Side: Biceps Femoris 83% MMT -flexes knee joint, laterally rotates the knee when flexed, extends hip joint (long head only) Left Side : Upper and Lower Gluteus Maximus 58% - extensor of the thigh on the pelvis, extensor of the pelvis on the thigh (and retroversion), Lateral rotator of the thigh. Left Side : Vastus Lateralis 58% -Knee extension
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Post by imperfectgolfer on Oct 27, 2018 9:21:46 GMT -5
Dr Mann You've said above "When I refer to the term "upper torso rotation" I am usually referring to the motion of that segment of the upper torso that includes the two shoulder sockets." So are you referring to any muscles that move the shoulder socket in space independent of any 'rolling' motion of the humerus head in that same socket? So for example, I have been reading this article below about muscle activity in the golf swing (which seems to be an amalgamation of different articles) bjsm.bmj.com/content/39/11/799I've then tried to understand the movements caused by the various main muscles they stated as being actively used in the 'Forward Swing ' and 'Acceleration' phases (which I've summarised below). From what I read below , there seems to be lots of muscle activity involved in moving the scapular in the upper body while secondary rotation of the lower/upper spine cause by the rotation of the pelvis. So doesn't it make sense that in males, the muscles involved in moving the scapular (and therefore the shoulder joint) in space are major generators of power than just the rotation of the spine/ribcage (and on average more powerful than female golfers)? So for clarification, when you mention upper body rotation, you don't just mean the rotational aspect of the shoulder socket caused 'only' by the rotation of the thoracic section of the spine, but also all the muscles that move the scapula too? DG ------------------- Forward swing The forward swing starts at the top of swing and ends when the club is horizontal to the ground (early part of down swing). The most active muscle in the upper body during this phase in the upper body on the left side is the rhomboid (68% MMT) and middle trapezuis (51% MMT). On the right side, the most active muscles are the pectoralis major (64% MMT) and upper serratus (58% MMT). The most active muscle during the forward swing phase in the lower body are the upper and lower gluteus maximus (100% MMT and 98% MM) on the right side along with the biceps femoris (78% MMT). On the left side, the most active muscles are the vastus lateralis (88% MMT) and the adductor magnus (63% MMT). Upper Body Left Side -Rhomboid 68% - Moves the Scapula (and therefore the shoulder socket) Left Side Middle Trapezius 51% - Moves the Scapula (and therefore the shoulder socket) Right Side :Pectoralis major 64%- adduction and internal rotation of the humerus Right Side : Upper Serratus 58% - Moves the Scapula (and therefore the shoulder socket) Lower Body Right Side : Upper and Lower Gluteus Maximus - 100% and 98% - extensor of the thigh on the pelvis, extensor of the pelvis on the thigh (and retroversion), Lateral rotator of the thigh. Right Side : Biceps femoris 78% - Flex the leg at the knee, laterally rotate the knee from the flexed position, extends the thigh at the hip. Left Side : Vastus Lateralis 88% -Knee extension Left Side : Adductor Magnus 63% -adductor of the thigh, hip extension, external rotation of knee as the thigh adducts. Acceleration The acceleration phase starts from the horizontal club to the impact of the ball (late part of down swing). This phase of the swing sees the pectoralis major muscle bilaterally being the most active muscle (93% MMT bilaterally) in the upper body. On the right side, the second most active muscle is the upper serratus anterior (69% MMT). On the left side, the levator scapulae is the second most active muscle (62% MMT). In the lower body, the acceleration phase sees the left biceps femoris (83% MMT) being the most active muscle with the left upper and lower gluteus maximus, along with the vastus lateralis being the second most active muscles (58% MMT). On the right side, the abdominal oblique (59% MMT) is the most active muscle, followed by the gluteus medius (51% MMT). Upper Body Right Side: Pectoralis Major 93% - adduction and internal rotation of the humerus Right Side : Upper Serratus Anterior 69% - Moves the Scapula (and therefore the shoulder socket) Left Side: Pectoralis Major 93% - adduction and internal rotation of the humerus Left Side: Levator Scapulae 62% - Levitates the Scapula (and therefore shoulder socket) Lower Body Right Side: Abdominal Oblique 59% - spinal rotation, anterior flexion of the spinal column, lateral flexion of spinal column. Right Side: Gluteus Medius 51% -One of the most powerful abductors and internal rotators of the hip (flexion and internal rotation, extension and external rotation) Left Side: Biceps Femoris 83% MMT - Left Side : Upper and Lower Gluteus Maximus 58% - extensor of the thigh on the pelvis, extensor of the pelvis on the thigh (and retroversion), Lateral rotator of the thigh. Left Side : Vastus Lateralis 58% -Knee extension You wrote-: " So doesn't it make sense that in males, the muscles involved in moving the scapular (and therefore the shoulder joint) in space are major generators of power than just the rotation of the spine/ribcage (and on average more powerful than female golfers)?
So for clarification, when you mention upper body rotation, you don't just mean the rotational aspect of the shoulder socket caused 'only' by the rotation of the thoracic section of the spine, but also all the muscles that move the scapula too?" No! Although the scapula moves relative to the upper torso's rib cage to a small degree, I do not believe that it contributes significantly to swing power. When I refer to the motion of the left shoulder socket I am referring to rotation of the upper torso area that incorporates the scapula and I think of them as primarily moving as an unitary structure. Look at these capture images of Jamie Sadlowski's early downswing. Image 1 is at P4 and his left scapula is protracted. Note that his left scapula gets more retracted between P4 and P5 and it therefore causes some targetwards motion of the left shoulder socket - that is independent of the targetwards motion of his left shoulder socket that is due to the counterclockwise rotation of his upper torso around his rightwards-tilted spine. However, I suspect that it is not a major determinant of the speed of targetwards motion of the left shoulder socket, which is primarily determined by the speed of counterclockwise rotation of the upper torso.
Jeff.
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Post by dubiousgolfer on Oct 27, 2018 17:04:07 GMT -5
Many thanks Dr Mann It does seem that MYSWING system has a means of measuring shoulder socket vs ribcage turn and rotational speed (see video below) and are suggesting that the movement of the scapula (retraction and protraction) can increase power if timed correctly with the turn of the ribcage. vimeo.com/172978377It would be interesting to see what data they have for LPGA vs PGA players and whether there is a relationship between 'shoulder socket' rotation amount/speed and ribcage rate of rotation. I suppose we will just have to await their findings being made available to the public. DG
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Post by imperfectgolfer on Oct 27, 2018 21:51:10 GMT -5
Many thanks Dr Mann It does seem that MYSWING system has a means of measuring shoulder socket vs ribcage turn and rotational speed (see video below) and are suggesting that the movement of the scapula (retraction and protraction) can increase power if timed correctly with the turn of the ribcage. vimeo.com/172978377It would be interesting to see what data they have for LPGA vs PGA players and whether there is a relationship between 'shoulder socket' rotation amount/speed and ribcage rate of rotation. I suppose we will just have to await their findings being made available to the public. DG I found this video more informative in showing the difference between rib cage versus shoulder rotation - vimeo.com/172974947However, there is only a 10 degrees difference in the degree of rotation and I am sceptical that it can significantly affect clubhead speed if that gap closes during the downswing - relative to the effect of the overall speed of counterclockwise rotation of both the rib cage/shoulders. More importantly, if they can measure these two parameters accurately, then they should be able to plot the speed of counterclockwise rotation of the rib cage and shoulders during the downswing in male and female pro golfers. I would like to see their measurements comparing a good PGA golfer (like Dustin Johnson) to a good LPGA golfer (like Brooke Henderson or Lexi Thompson). Jeff.
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Post by dubiousgolfer on Oct 28, 2018 7:49:03 GMT -5
Yes , thanks for the link to that video as it was more informative. It was made 2 years ago , so I am assuming they may already have data on the PGA/LPGA players (pity we can't see it). DG PS. With regards the possibility of creating more 'initial ' clubhead speed before CF induced release , I was looking at Tutelman's theory about the extra clubhead speed being caused in Lee Comeux's swing where he used the diagram below. But he assumed that a 'force' applied on the grip via the right hand was due to a 'torque' actively applied by a more active right side pivot rotation) with a 'Force radius' as shown (the red line towards the centre of the spine at the base of the neck) www.tutelman.com/golf/swing/leecommotion1.phpBut if we discounted the above and theorised that there was a degree of torque caused by shoulder girdle movement in the early downswing, one could imagine a ' Right Shoulder Girdle Force Radius' shorter than Tutelman's diagram above? The point of origin of that radius would be somewhere nearer the right scapula (see diagram below ) than towards the centre of the upper spine area. The question would then become how much 'Force' can be generated by just the movement of that right shoulder girdle over a small distance in that 'straighter path' in the early downswing. I cannot imagine that there will be a significant extra force caused by independent left shoulder girdle movement. Anyhow, just a thought on how the physics might pan out if there was any hard evidence to support it.
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Post by imperfectgolfer on Oct 28, 2018 9:06:59 GMT -5
Yes , thanks for the link to that video as it was more informative. It was made 2 years ago , so I am assuming they may already have data on the PGA/LPGA players (pity we can't see it). DG PS. With regards the possibility of creating more 'initial ' clubhead speed before CF induced release , I was looking at Tutelman's theory about the extra clubhead speed being caused in Lee Comeux's swing where he used the diagram below. But he assumed that a 'force' applied on the grip via the right hand was due to a 'torque' actively applied by a more active right side pivot rotation) with a 'Force radius' as shown (the red line towards the centre of the spine at the base of the neck) www.tutelman.com/golf/swing/leecommotion1.phpBut if we discounted the above and theorised that there was a degree of torque caused by shoulder girdle movement in the early downswing, one could imagine a ' Right Shoulder Girdle Force Radius' shorter than Tutelman's diagram above? The point of origin of that radius would be somewhere nearer the right scapula (see diagram below ) than towards the centre of the upper spine area. The question would then become how much 'Force' can be generated by just the movement of that right shoulder girdle over a small distance in that 'straighter path' in the early downswing. I cannot imagine that there will be a significant extra force caused by independent left shoulder girdle movement. Anyhow, just a thought on how the physics might pan out if there was any hard evidence to support it. I am sceptical that a golfer, who uses a TGM swinging action, produces a greater amount of swing power either via the pivot action working through the shorter right arm radius (as suggested by Tutelman) or via a protraction of the right scapula at the start of the downswing - because a TGM swinger does not want the right shoulder area to actively move forward in any "OTT move" manner. In fact, many golf instructors encourage a golfer to keep the right shoulder back at the start of the downswing and ingrain a "feel" of right shoulder motional quiesence. Jeff.
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Post by dubiousgolfer on Oct 31, 2018 10:56:03 GMT -5
Dr Mann I have been reading this article below and wondering what your opinions are especially the 'utilising the stretch shortening cycle (SSC)'? Could this SSC be an important factor in why PGA men can drive longer distances than LPGA (even with, on average, less hip/ribcage speed)? www.mytpi.com/articles/fitness/x-factor_essentials_what_it_is_and_how_to_train_itIt's strange , but I do remember Kuykendall (whose opinions you might disagree with) mentioning the role of 'fast twitch/slow twitch ' muscles in generating clubhead speed (but he was more vociferous about them being used in the arms than other parts of the body). But isn't SSC and 'Power' generation dependent on the ratios of 'fast twitch/slow twitch fibers' in muscles used in the golf swing, and which ones needs to be active for clubhead speed/stabilisation and overall rhythm? For example , LPGA players might have on average higher ribcage/hip speeds , but their SSC contributions might be inferior to the PGA men. Could that be a possible explanation as to why men drive the ball further than the women? I suspect it cannot be proved one way or the other until more detailed research studies are done ensuring that there is limited bias in the sample groups dependent on their swing technique actions and ability. DG
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Post by imperfectgolfer on Oct 31, 2018 17:59:00 GMT -5
Dr Mann I have been reading this article below and wondering what your opinions are especially the 'utilising the stretch shortening cycle (SSC)'? Could this SSC be an important factor in why PGA men can drive longer distances than LPGA (even with, on average, less hip/ribcage speed)? www.mytpi.com/articles/fitness/x-factor_essentials_what_it_is_and_how_to_train_itIt's strange , but I do remember Kuykendall (whose opinions you might disagree with) mentioning the role of 'fast twitch/slow twitch ' muscles in generating clubhead speed (but he was more vociferous about them being used in the arms than other parts of the body). But isn't SSC and 'Power' generation dependent on the ratios of 'fast twitch/slow twitch fibers' in muscles used in the golf swing, and which ones needs to be active for clubhead speed/stabilisation and overall rhythm? For example , LPGA players might have on average higher ribcage/hip speeds , but their SSC contributions might be inferior to the PGA men. Could that be a possible explanation as to why men drive the ball further than the women? I suspect it cannot be proved one way or the other until more detailed research studies are done ensuring that there is limited bias in the sample groups dependent on their swing technique actions and ability. DG I have zero sympathy for the "belief" that the stretch-shorten cycle applies to the torso muscles that rotate the mid-upper torso. First of all, a "stretch-shorten cycle" is not based on the storing of elastic energy (as that junk science article implies). It works on the "idea" of pre-stretching a muscle immediately before the muscle contracts so that the muscle can contract with greater force than usual eg. when jumping off a 3 foot high bench onto the ground and then immediately jumping up. That pre-stretching force applied to the calf muscles is considerable in magnitude when the weight of the entire body is applying the "stretching force" and when the pre-stretch is happening very fast as the person lands on the ground. By contrast, when the pelvis rotates counterclockwise at the start of the downswing the "pre-stretch force" that it applies to the abdominal oblique muscles is not that large in most golfers (if they cannot generate an inordinate amount of torso-pelvic separation like Cameron Champ), and I personally do not think that it is a significant biomechanical phenomenon in the overall efficiency of contraction of the abdominal oblique muscles that rotate the mid-upper torso counterclockwise. Jeff.
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Post by dubiousgolfer on Oct 31, 2018 20:38:55 GMT -5
Many thanks Dr Mann
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Post by dubiousgolfer on Nov 1, 2018 8:42:23 GMT -5
Dr Mann
I have a suspicion that I know why Soloman (that 3D Director) mentioned the 'hands' being the major difference in clubhead speed for PGA men vs LPGA females. From what Dan Carraher said, Soloman works closely with Phil Cheetham , who in turn I've seen on videos with Chuck Evans .
Chuck Evans produced this video below sometime ago , but I can imagine that Soloman has just reiterated what Mr Evans implied in that video but said 'Hands' instead of 'wrists' (Chuck Evans should maybe also have said forearms rather than wrists for the rolling action).
The strange thing is that the % contributions used in the video were the same for Men and Women (apart from the legs contribution where the Women were greater than Men) so unsure where they got this data saying that LPGA women 'on average' have higher ribcage rotation than PGA men (unless this is more recent data).
Incredibly vague video , especially because he never explained biomechancially how leg participation contributed to clubhead speed. He also seemed to infer active cocking /uncocking wrists (which doesn't make sense to me because it should be a passive CF induced release)
Driver Legs: 21% men , 26% women Core: 10% men & women Shoulders: 12% & women Wrist : 56% men & women
I think the 'Sandtrap forum' pros also produced a very unscientific video below to demonstrate approx contributions (but specifically to show that vertical GRF play a very small part in generating clubhead speed). But in essence they also agreed with the percentages quoted in Chuck Evans video.
Quote From Iacas
"Most people talk only about the vertical GRF. But those are a small portion of the GRF, and within the swing itself, an even smaller portion of the contribution to swing speed.
Just swinging your arms is about 75% of your swing speed.
The horizontal ("rotational") speed (seen in shear GRF forces) are about 20%.
The vertical GRF stuff is about 5%. And most people already use a bit of that - almost nobody uses 0% of that 5%."
DG
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