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Post by dubiousgolfer on May 15, 2019 7:36:09 GMT -5
I have been looking through Tutelman's website again regarding statements made by himself, Jorgensen and Rod White , specifically the following which interested me.
Rod White 1. It is generally helpful to apply negative torque (that is, hold the lag angle, retard release) throughout the downswing. 2. The negative effect of wrist torque and the positive effect of wrist cock, account for most of the 70 m difference between the beginner and the scratch golfer
During the first part of the downswing, the golfer holds the club in a cocked position and accelerates the shoulders and torso. Initially some positive wrist torque is required to stop the club from being pulled into the golfers neck (the hub). Remember the passive, steadily rotating model on the previous page? There, a string (providing negative torque) was needed to keep the club from swinging outward. Here, during the initial build up of speed, some sort of "brace" (providing positive torque) is needed prevent the club from being pulled inward. The positive torque required to brace the club falls rapidly as the club accelerates. When the positive ‘bracing’ torque falls to zero, the club can be allowed to swing out -- ending the first phase.
The second phase of the downswing occurs as the club swings out. If the golfer lets the club swing out when the bracing torque falls to zero, then this is described as a swing with a natural release. If the golfer holds the club in the cocked position for a short while longer, this is described as a late release. If the golfer releases the club early, the club will swing in towards the neck for a small moment and then swing out. We won’t look at the effect of release timing because to a good approximation release timing has no effect.
During the second phase the golfer continues to turn his body and arms, but no torque is applied via the hands – they are no more than a hinge during this phase.
Jorgensen or Tutelman (couldn't tell who made this statement) You can increase the clubhead speed at impact by using a hindering hand action. This is paradoxical, counterintuitive -- but the model says it is true. And I know at least one instructor who gets very good results teaching a hand action that tries to hold the wrist cock right through impact -- a swing key that creates a hindering torque.
General consensus among those who have investigated the swing mathematically:
1. A strong shoulder turn increases clubhead speed. (The model does not say whether the turn should be a product of the shoulders, the torso, the hips, the legs,... Just that a strong turn powers the swing well.)
2. Wrist torque that helps release usually winds up hurting clubhead speed at impact. You may get higher clubhead speeds earlier in the downswing, but those speeds don't hit the ball; by the time of impact, the clubhead speed is lower than with no wrist torque at all.
3. Wrist torque that retards or delays release usually winds up increasing clubhead speed at impact. #2 and #3 are recognized as paradoxical, but they work time and time again on the computer -- and also on the driving range.
4. When it comes to a "pulse" of helping torque just before impact, there is no consensus. Jorgensen found there is some small advantage to be gained. Wishon believes it is nearly impossible for a real, live human being to achieve that gain.
Query: Looking at all the bolded statements above my issue is:
How can one 'hold' the lag angle throughout the downswing? Doesn't that mean the wrists are not acting just like a hinge during the 2nd phase of the downswing? How can one 'hold' (or apply negative torque) while also allowing 'release' all the way into impact?
Imho, it seems like a contradiction unless there was a way to create 'lag' without using 'active' wrist negative' torque? That would mean using biomechanical actions that would evoke the same 'CF force phenomenon' to create a 'lagging effect' as well as a 'release effect' (ie. with the wrists acting just like a oily hinge).
DB
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Post by imperfectgolfer on May 15, 2019 9:11:35 GMT -5
I have been looking through Tutelman's website again regarding statements made by himself, Jorgensen and Rod White , specifically the following which interested me. Rod White 1. It is generally helpful to apply negative torque (that is, hold the lag angle, retard release) throughout the downswing. 2. The negative effect of wrist torque and the positive effect of wrist cock, account for most of the 70 m difference between the beginner and the scratch golfer During the first part of the downswing, the golfer holds the club in a cocked position and accelerates the shoulders and torso. Initially some positive wrist torque is required to stop the club from being pulled into the golfers neck (the hub). Remember the passive, steadily rotating model on the previous page? There, a string (providing negative torque) was needed to keep the club from swinging outward. Here, during the initial build up of speed, some sort of "brace" (providing positive torque) is needed prevent the club from being pulled inward. The positive torque required to brace the club falls rapidly as the club accelerates. When the positive ‘bracing’ torque falls to zero, the club can be allowed to swing out -- ending the first phase. The second phase of the downswing occurs as the club swings out. If the golfer lets the club swing out when the bracing torque falls to zero, then this is described as a swing with a natural release. If the golfer holds the club in the cocked position for a short while longer, this is described as a late release. If the golfer releases the club early, the club will swing in towards the neck for a small moment and then swing out. We won’t look at the effect of release timing because to a good approximation release timing has no effect. During the second phase the golfer continues to turn his body and arms, but no torque is applied via the hands – they are no more than a hinge during this phase. Jorgensen or Tutelman (couldn't tell who made this statement) You can increase the clubhead speed at impact by using a hindering hand action. This is paradoxical, counterintuitive -- but the model says it is true. And I know at least one instructor who gets very good results teaching a hand action that tries to hold the wrist cock right through impact -- a swing key that creates a hindering torque. General consensus among those who have investigated the swing mathematically:
1. A strong shoulder turn increases clubhead speed. (The model does not say whether the turn should be a product of the shoulders, the torso, the hips, the legs,... Just that a strong turn powers the swing well.) 2. Wrist torque that helps release usually winds up hurting clubhead speed at impact. You may get higher clubhead speeds earlier in the downswing, but those speeds don't hit the ball; by the time of impact, the clubhead speed is lower than with no wrist torque at all. 3. Wrist torque that retards or delays release usually winds up increasing clubhead speed at impact. #2 and #3 are recognized as paradoxical, but they work time and time again on the computer -- and also on the driving range. 4. When it comes to a "pulse" of helping torque just before impact, there is no consensus. Jorgensen found there is some small advantage to be gained. Wishon believes it is nearly impossible for a real, live human being to achieve that gain. Query: Looking at all the bolded statements above my issue is: How can one 'hold' the lag angle throughout the downswing? Doesn't that mean the wrists are not acting just like a hinge during the 2nd phase of the downswing? How can one 'hold' (or apply negative torque) while also allowing 'release' all the way into impact? Imho, it seems like a contradiction unless there was a way to create 'lag' without using 'active' wrist negative' torque? That would mean using biomechanical actions that would evoke the same 'CF force phenomenon' to create a 'lagging effect' as well as a 'release effect' (ie. with the wrists acting just like a oily hinge). DB I believe that it is advantageous in terms of clubhead speed to delay the release of PA#2. However, one cannot prevent an early PA#2 release by trying to maintain the left wrist upcock manually (using a negative wrist torque) because it will interfere with the free release of PA#2 (according to the D'Alembert principle).
I only recommend two biomechanical techniques to delay the release of PA#2. 1) Technique number 1 : Create a hand arc path that has a long straight-line section between P4 and P5.5 - as seen in this image of Dustin Johnson's golf swing. The splined red line represents his hand arc path.
Image 3 shows that Dustin's hands are about 12" outside his right thigh at P5.5 (image 3) and his hands are no closer to the target at P5.5 than it was at P4 (image 1). That means that his hands are moving near-vertically downwards between P4 and P5.5 - primarily due to his active right arm adduction maneuver that is combined with a pitch elbow motion. Note that his right elbow is much closer to the target at P5.5 than his hands and that his right forearm is angled outwards and backwards - due to his pitch elbow action. The pitch elbow motion combined with his retention of right elbow bend allows him to create a hand arc path between P4 and P5.5 that is nearly "straight and minimally curved" and that prevents the release of PA#2 (according to the D'Alembert principle).
2) Technique number 2. Maintaining a bent right elbow elbow while performing a pitch elbow motion between P4 and P5.5 (while simultaneously obtaining a significant level of right lateral bend) allows Dustin to more easily maintain his lag all the way down to P5.5. This would not happen if he used a punch elbow motion or prematurely straightened his right arm.
Jeff.
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Post by dubiousgolfer on May 15, 2019 10:02:58 GMT -5
Many thanks Dr Mann Tutelman mentions another way to create lag using the method below. Is this same as your 2nd suggested technique? Suppose the right arm is pulling and the left is pushing. That creates a "negative torque", a torque that tends to prevent the club from releasing. It will encourage holding and perhaps even increasing the clubhead lag. This is not mere speculation. Kelvin Miyahira has been looking at lag from a biomechanics viewpoint rather than the physics approach I am comfortable with. By studying videos of golfers (including a lot of Tour players), he has identified a number of "micro-moves" that encourage the retention of clubhead lag. Two of the important micro-moves are left arm extension and a right elbow tucked down in front of the body through almost the entire downswing. That is exactly the diagram we show here: The extended left arm is a pushing force at the butt of the grip. Tucking the right elbow prevents it from extending, "shortening" the right arm. Do this assertively and not just passively, and the right hand is pulling the grip. The net result is a negative torque, one that prevents the release of the lag until inertial forces are irresistible in releasing the clubhead. Kelvin's observation is consistent with physics theory in this regard. DB
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Post by imperfectgolfer on May 15, 2019 10:51:25 GMT -5
Many thanks Dr Mann Tutelman mentions another way to create lag using the method below. Is this same as your 2nd suggested technique? Suppose the right arm is pulling and the left is pushing. That creates a "negative torque", a torque that tends to prevent the club from releasing. It will encourage holding and perhaps even increasing the clubhead lag. This is not mere speculation. Kelvin Miyahira has been looking at lag from a biomechanics viewpoint rather than the physics approach I am comfortable with. By studying videos of golfers (including a lot of Tour players), he has identified a number of "micro-moves" that encourage the retention of clubhead lag. Two of the important micro-moves are left arm extension and a right elbow tucked down in front of the body through almost the entire downswing. That is exactly the diagram we show here: The extended left arm is a pushing force at the butt of the grip. Tucking the right elbow prevents it from extending, "shortening" the right arm. Do this assertively and not just passively, and the right hand is pulling the grip. The net result is a negative torque, one that prevents the release of the lag until inertial forces are irresistible in releasing the clubhead. Kelvin's observation is consistent with physics theory in this regard. DB I totally disagree with the "idea" of using the left hand to actively push outwards (away from the target) against the club handle because I think that it is artificial and unnatural (other than the small amount due to maintaining a straight left arm). Nonetheless, even if the straight left arm is not actively pushing outwards (away from the target during the early downswing) it is an obvious fact that the left arm is more horizontal at P5 compared to P4 and that "fact" automatically/naturally means that there is push-force working outwards away from the target between P4 and P5 (secondary to the rotation of the upper torso) - note that DJ's hand arc path is directed slightly away from the target between P4 and P5. Also, if the right elbow is kept bent and the right arm is actively adducted while performing a pitch elbow motion of the right elbow then there will be a small pull inwards performed with the right hand, which helps to maintain lag. Jeff.
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Post by dubiousgolfer on May 15, 2019 17:01:57 GMT -5
Many thanks Dr Mann
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Post by dubiousgolfer on May 17, 2019 7:41:54 GMT -5
Dr Mann
On reflection , I am confused about the 2 techniques you mentioned above . Aren't they the same? If they are different is DJ doing technique 1 or 2?
I always thought a pitch elbow motion included an adduction or are they separate anatomical movements?
When I look for a definition of adduction of the arm it says this:
"Adduction is the movement of a body part toward the body's midline. So, if a person has their arms straight out at the shoulders and brings them down to their sides, it is adduction."
So is 'pitch elbow' motion really the 'lateral rotation' of the humerus? If yes, doesn't this mean that :
a. Technique 1 is adduction of humerus first, then 'lateral rotation humerus' & 'right lateral bend' happening simultaneously slighty later? b. Technique 2 is 'adduction humerus' & 'lateral rotation humerus' & 'right lateral bend' happening simultaneously?
In your opinion, which 2 PGA pro golfers swings could typify both techniques?
DB
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Post by imperfectgolfer on May 17, 2019 9:11:37 GMT -5
Dr Mann On reflection , I am confused about the 2 techniques you mentioned above . Aren't they the same? If they are different is DJ doing technique 1 or 2? I always thought a pitch elbow motion included an adduction or are they separate anatomical movements? When I look for a definition of adduction of the arm it says this: "Adduction is the movement of a body part toward the body's midline. So, if a person has their arms straight out at the shoulders and brings them down to their sides, it is adduction." So is 'pitch elbow' motion really the 'lateral rotation' of the humerus? If yes, doesn't this mean that : a. Technique 1 is adduction of humerus first, then 'lateral rotation humerus' & 'right lateral bend' happening simultaneously slighty later? b. Technique 2 is 'adduction humerus' & 'lateral rotation humerus' & 'right lateral bend' happening simultaneously? In your opinion, which 2 PGA pro golfers swings could typify both techniques? DB The two techniques I described with respect to DJ are the same in the sense that they involve the identical biomechanical movements. However, it is theoretically possible to create a long "straight-line" hand arc path between P4 and P5.5 using the left arm alone - but it is useful to have the right arm's pitch elbow motion synergistically assist in optimising the hand arc path. The same right elbow pitch motion also assists a golfer in retaining lag for longer. A pitch elbow motion includes an adduction of the right humerus, but it specifically also includes i) external rotation of the right humerus + ii) supination of the right forearm. Those latter two movements cause the right hand to be well to the right of the right elbow at P5.5 (which means that the "right elbow is leading the hands" in a targetwards direction during the early-mid downswing). Right lateral bend is optional and it is useful if one wants to shallow the clubshaft down to a shallower plane by P5.5 (eg. hand plane as seen in Sergio Garcia's and Hunter Mahan's downswing actions). If a golfer adducted the right humerus, but internally rotated the right humerus while pronating the right forearm, then he would be executing a punch elbow motion where the "hands lead the right elbow" and this will likely lead to a "tumble action" (= Malaska type of right hand motion). Jeff.
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Post by dubiousgolfer on May 17, 2019 9:20:54 GMT -5
Many thanks for the clarification Dr Mann
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Post by dubiousgolfer on May 23, 2019 12:34:53 GMT -5
Dr Mann Do you think that golfers like DJ and Cameron Champ are more likely to use their pivot to release PA4 because of the vertical position of their lead arm at the top of the backswing? For example , you mentioned Jamie Sadlowski below: --------------- Note that I have placed a green circle marker over his left shoulder socket area when he is at the P4 position (image 1) to show the position of his left shoulder socket. Note that I have placed a yellow circle marker over his left shoulder socket area when he is at his P4.5 position (image 2), and that I have placed a blue circle marker over his left shoulder socket area when he is at his P5 position (image 3). If you look at the motion of his left shoulder socket between P4 and P5, you can see that it is moving in a relatively horizontal direction towards the target. The amount of left shoulder socket motion (in a targetwards direction) happening between P4 and P5 is a major swing power factor when it comes to a golfer's ability to unload PA#4 with maximum efficiency because the targetwards motion of his left shoulder socket is causally responsible for pulling his left humeral head, and therefore his left upper arm, in a targetwards direction. However, the targetwards range of motion of the left shoulder socket happening between P4 and P5 is only one swing power factor that determines the speed of release of PA#4 and it is also very important to move the left shoulder socket, and therefore the left upper arm, very fast between P4 and P5. The speed of left shoulder socket motion happening between P4 and P5 is directly proportional to the speed of rotation of the upper torso happening during that time period. Jamie Sadlowski, like most professional golfers, uses an optimised kinematic sequence, that allows him to maximise his speed of upper torso rotation between P4 and P5. ------------------------------------ But then you mentioned Jon Rahms swing where his lead arm gets to about 11 O'Clock at the top of his backswing I strongly suspect that his shoulder girdle muscles (both left and right) could be his major swing power sources that move his hands very fast down his hand arc path between P4 and P5.5 - and they could be considered to the major swing power source for the vertical component (left arm depression component) of his PA#4 release action while his upper torso's rotation is likely to be the major swing power source for the transverse component (left arm abductory component) of his PA#4 release action. ------------- My question: Could their be a relationship between the use of 'TGM Swinging' vs 'Right Arm Swinging' techniques depending on how vertical the lead arm gets in the backswing? How can a golfer create hand speed along that 'straightish' hand path between 'P4 and release' (using the pivot to release PA#4) if the backswing is quite short and the lead arm more horizontal than vertical at P4? It seems that the shoulder girdle muscles (especially the right) is in a more advantaged position for moving the lead arm down at speed from 'P4-Release'. DG
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Post by imperfectgolfer on May 23, 2019 16:55:55 GMT -5
Dr Mann Do you think that golfers like DJ and Cameron Champ are more likely to use their pivot to release PA4 because of the vertical position of their lead arm at the top of the backswing? For example , you mentioned Jamie Sadlowski below: --------------- Note that I have placed a green circle marker over his left shoulder socket area when he is at the P4 position (image 1) to show the position of his left shoulder socket. Note that I have placed a yellow circle marker over his left shoulder socket area when he is at his P4.5 position (image 2), and that I have placed a blue circle marker over his left shoulder socket area when he is at his P5 position (image 3). If you look at the motion of his left shoulder socket between P4 and P5, you can see that it is moving in a relatively horizontal direction towards the target. The amount of left shoulder socket motion (in a targetwards direction) happening between P4 and P5 is a major swing power factor when it comes to a golfer's ability to unload PA#4 with maximum efficiency because the targetwards motion of his left shoulder socket is causally responsible for pulling his left humeral head, and therefore his left upper arm, in a targetwards direction. However, the targetwards range of motion of the left shoulder socket happening between P4 and P5 is only one swing power factor that determines the speed of release of PA#4 and it is also very important to move the left shoulder socket, and therefore the left upper arm, very fast between P4 and P5. The speed of left shoulder socket motion happening between P4 and P5 is directly proportional to the speed of rotation of the upper torso happening during that time period. Jamie Sadlowski, like most professional golfers, uses an optimised kinematic sequence, that allows him to maximise his speed of upper torso rotation between P4 and P5. ------------------------------------ But then you mentioned Jon Rahms swing where his lead arm gets to about 11 O'Clock at the top of his backswing I strongly suspect that his shoulder girdle muscles (both left and right) could be his major swing power sources that move his hands very fast down his hand arc path between P4 and P5.5 - and they could be considered to the major swing power source for the vertical component (left arm depression component) of his PA#4 release action while his upper torso's rotation is likely to be the major swing power source for the transverse component (left arm abductory component) of his PA#4 release action. ------------- My question: Could their be a relationship between the use of 'TGM Swinging' vs 'Right Arm Swinging' techniques depending on how vertical the lead arm gets in the backswing? How can a golfer create hand speed along that 'straightish' hand path between 'P4 and release' (using the pivot to release PA#4) if the backswing is quite short and the lead arm more horizontal than vertical at P4? It seems that the shoulder girdle muscles (especially the right) is in a more advantaged position for moving the lead arm down at speed from 'P4-Release'. DG It is seemingly true that the pivot can likely induce a PA#4 release action more powerfully if the left arm is more vertical at P4 and if the left shoulder socket has moved more rightwards-and-upwards by P4. However, if you look at images 1 and 2 of the Rahm sequence, one can still discern that there is lot of left shoulder socket motion happening between P4 and P5 to induce a PA#4 release action. It would be wonderful if golf researchers placed pressure sensors at PP#1 to determine how much the right palm is pushing against PP#1 in a groundwards direction between P4 and P5 - because it would allow one to better "guesstimate" how much PA#5 is being used by Rahm. Jeff.
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