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Post by dubiousgolfer on Jan 5, 2022 12:02:51 GMT -5
Many thanks Dr Mann- I had the same problem trying to understand how Dr Kwon could possibly connect GRF torques to a real golfers swing . I can imagine for example that golfers could move their bodies in many different ways and still produce the same net GRF force and possibly the same torque about the COM/COR. So it doesn't really provide any practical guidance on what real elite golfers are doing in their swings.
DG
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Post by imperfectgolfer on Jan 5, 2022 12:18:16 GMT -5
Many thanks Dr Mann- I had the same problem trying to understand how Dr Kwon could possibly connect GRF torques to a real golfers swing . I can imagine for example that golfers could move their bodies in many different ways and still produce the same net GRF force and possibly the same torque about the COM/COR. So it doesn't really provide any practical guidance on what real elite golfers are doing in their swings. DG Talking about vertical GRFS being generated under the feet gives a student-golfer no useful golf instructional idea about how to use those vertical GRFs from a golf instructional perspective. Think back on all the good advice that Kwon gave Brendon in his visit to Kwon's lab. He taught Brendon to start the downswing's pivot motion with a pelvic shift-rotation motion and to keep the upper torso passively closed for a short period of time during the early P4 => P4.5 transition to the downswing. Kwon also taught Brendon not to move the club handle actively with his hands in an OTT manner at the very start of the downswing, and he taught him to allow the arms/club to passively shallow-out by getting the kinematic sequence correct by starting the downswing with an active pelvic rotary motion. Kwon also taught Brendon how the arms/club must move around the rotating torso in a circular in-to-in manner where the clubshaft can be directed to move along the functional swingplane between P6 => P8. All that practical advice was very useful, but it's closed chain advice that deals with what is happening within the inner workings of the closed chain phenomenon of a full golf swing action. What useful advice can be derived from the statement that "the only way to get external forces to move the body in a full golf swing action is through vertical/horizontal GRFS being generated under the two feet"? Jeff.
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Post by dubiousgolfer on Jan 6, 2022 9:37:52 GMT -5
Dr Mann Would you agree that these step drills might not help golfers who tend to use a reverse weight shift style foot action from approx P6 ? DG
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Post by imperfectgolfer on Jan 6, 2022 10:06:10 GMT -5
Dr Mann Would you agree that these step drills might not help golfers who tend to use a reverse weight shift style foot action from approx P6 ? DG I don't think that the step drills will not help golfers who are reverse-foot golfers. The step drills help a golfer improve his shift-rotation of the pelvis during the backswing (step drill number 1) and early downswing between P4 => P5 (step drill number 2). Reverse-foot golfers do not continue to increase their pressure loading of the lead foot after P6, but that phenomenon is happening in the later downswing. Jeff.
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Post by dubiousgolfer on Jan 6, 2022 18:23:04 GMT -5
Many thanks Dr Mann
Here is Brendon's most recent swing but it still looks a bit OTT to me.
DG
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Post by imperfectgolfer on Jan 6, 2022 22:25:03 GMT -5
Many thanks Dr Mann Here is Brendon's most recent swing but it still looks a bit OTT to me. DG It is definitely still OTT. He has gone back to his usual swing fault of starting to rotate his upper torso too soon. Kwon warned him to have a "mature backswing" where he waits for his upper torso/lead arm to keep moving clockwise to its final P4 position while he first starts rotating his pelvis counterclockwise while simultaneously keeping his upper torso temporarily closed. He is rushing his downswing by moving his upper torso and pelvis at the same time - and he is back to his "old" swing pattern. Jeff.
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Post by dubiousgolfer on Jan 7, 2022 7:26:18 GMT -5
Dr Mann
I did ask Dr Kwon about his step drills and whether they would apply to reverse foot golfers and this was his reply
"The steps drills are used to discourage the reverse-foot pattern."
DG
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Post by dubiousgolfer on Jan 7, 2022 20:17:32 GMT -5
Dr Mann
What do you think about Dr Kwon's wrist action instruction at 40:16 -40:46? It looks like a 'non-delayed full-roll non-DH hand release action' (a TGM HH action).
DG
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Post by imperfectgolfer on Jan 7, 2022 21:50:20 GMT -5
Dr Mann I did ask Dr Kwon about his step drills and whether they would apply to reverse foot golfers and this was his reply "The steps drills are used to discourage the reverse-foot pattern." DG Interesting! Although I prefer the front-foot pattern, I think that the reverse-foot pattern can work very well for certain pro golfers. Jeff.
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Post by imperfectgolfer on Jan 7, 2022 22:02:00 GMT -5
Dr Mann What do you think about Dr Kwon's wrist action instruction at 40:16 -40:46? It looks like a 'non-delayed full-roll non-DH hand release action' (a TGM HH action). DG I think that Kwon's instruction regarding a hand release action through impact is sub-optimal. This particular golfer rotates his pelvis/torso very well through impact and he very naturally has a natural biomechanical tendency to perform a DH-hand release action between P7 => P7.4. However, Kwon does not like that pattern and he wants him to allow the clubshaft to bypass his lead arm through impact by slowing the targetwards motion of his lead arm and by having more relaxed wrists, which means that he favors a non-DH hand release action through impact. Phew! I obviously do not agree with his teaching philosophy. Jeff.
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Post by imperfectgolfer on Jan 8, 2022 10:24:07 GMT -5
The more I watch that Kwon video featuring Jim Sheridan, the more I disagree with Kwon's golf instructional approach. At the 40:10 minute time point of the video, Kwon states that he does not like the fact that Jim's lead wrist does not bend or rotate through impact and Kwon states that Jim should "leave more room for wrist motion". To demonstrate the type of lead wrist motion that he wants, Kwon takes the club and demonstrates how he wants the lead wrist to behave through impact. Note that Kwon performs a lead forearm supinatory motion through impact so that the back of his lead wrist rotates so much counterclockwise between P7 => P7.4 that it faces the ground by P7.4. That represents what I call a rolling subtype of non-DH hand release action, which is going to produce a higher clubface ROC through the immediate impact zone between P7 => P7.2+. I think that Jim had naturally acquired a tendency to perform a no-roll subtype of DH-hand release action through impact, which I believe is very desirable and it is of PGA tour quality. Kwon is actually teaching Jim to become a non-DHer, which I think is harmful and not desirable. I suspect that Kwon is mentally unaware of the advantages of performing a DH-hand release action through impact - as demonstrated by Cameron Champ in the following capture images. Note that Cameron Champ is using the bowed lead wrist technique of performing a DH-hand release action where the clubshaft does not bypass his lead arm (from an angular rotational perspective) between P7 => P7.4 (image 3). There are two major techniques that can be used used to perform a DH-hand release action through impact - i) the intact LFFW/GFLW technique and the ii) bowed lead wrist technique. Both techniques are very effective, although the bowed lead wrist technique (as performed by Cameron Champ and Collin Morikawa and Jon Rahm and Jim Sheridan) enables a golfer a to have a greater degree of mechanical stability of the lead wrist through impact. It is very sad to see Jim Sheridan being taught not to continue to use his very efficient DH-hand release action through impact.
There is a major difference between Kwon's and my teaching with respect to to the "feel" of the club through impact. Kwon talks about a golfer acquiring a "feel" of the clubhead motion through impact, while I believe that a golfer should acquire a "feel" of the clubshaft motion through impact, which allows one to more efficiently keep the LFFW intact.
I also think that Kwon's kettle bell drill has no value. He actually encouraged Jim to not bend his trail elbow during the backswing action. That makes no sense to me, because virtually all pro golfers bend their trail elbow between P1 => P4 so that the RFFW can be optimally aligned relative to the intact LFFW at P4, and there is no value in resisting-or-decreasing the requisite amount of trail elbow bending required to correctly align the RFFW relative to the intact LFFW by P4. I also think that Kwon telling Jim to more actively perform an exaggerated trigger motion (where he must throw the arms/club more actively targetwards before starting the backswing action) is not useful. Kwon argues that it will help Jim more efficiently load his backswing action with a greater degree of force, and he argues that it will allow Jim to then rotate his pelvis/torso more efficiently in his downswing. I think that a golfer needs to learn to perform the backswing loading action efficiently without needing to perform a preliminary exaggerated trigger motion because it obviously cannot be used in a "real life" golf swing action where a ball is present in the clubhead path. Jeff.
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Post by imperfectgolfer on Jan 9, 2022 10:18:39 GMT -5
Further comments on why I think that Kwon teaching Jim Sheridan to have more wrist motion through impact is potentially disadvantageous. First of all, I believe that performing a DH-hand release action results in a lower clubface ROC after impact to P7.2+, but that it does not necessarily mean that it actually decreases the clubface ROC at the exact moment of impact while the clubface is in continuous contact with the ball. Secondly, I know of no evidence that a pro golfer who has higher a clubface ROC at the moment of ball impact hits the ball less accurately than a pro golfer who has a low clubface ROC at the moment of ball impact. I think that hitting the ball straight at the desired target using a straight ball flight requires that the golfer zero-out the clubhead path and clubface angle at impact and also hit the ball on the clubface's sweetspot. That means that pre-impact factors related to the release of PA#2 and PA#3 play a major determinative role in hitting the ball straight, and I do not believe that converting from a non-DH hand release action to a DH-hand release action will necessarily play any significant role in improving a pro golfer's ability to hit the ball straight.
Nonetheless, I personally favor using a DH-hand release action because it will likely keep the clubface more square relative to the clubhead path between P7 => P7.2. Whether it will actually allow a skilled golfer, who has a high clubface ROC through impact, to hit the ball more consistently straight has never been studied (according to SMK). Therefore, we have no scientific evidence to back up my personal preference for a DH-hand release action. I simply think that it makes sense based on empirical reasoning. What I do believe is that one should not impose one's "strong belief" about the value (or lack of value) of a DH-hand release on a student-golfer. So, for example, if I were teaching a student-golfer, who used a non-DH hand release action, I would not try and convert him to performing a DH-hand release action. The reverse situation also applies, if I was teaching a student-golfer who naturally performed a DH-hand release action using the bowed lead wrist technique (like Jon Rahm, Cameron Champ, Collin Morikawa and Jim Sheridan), I would not try and convert him to having more wrist motion through impact so that he could become a non-DHer. I cannot think of any advantage of converting those 4 mentioned DHers to become non-DHers. Why was Kwon trying to induce Jim Sheridan to have more wrist motion through the immediate impact zone if Jim had a natural tendency, and the requisite skill, to flawlessly execute a DH-hand release action from P7 => P7.4? What advantage would Jim gain by adding more wrist motion through impact? I can think of one potential disadvantage if the added wrist motion was inconsistent and unreliable, and that would be a variable clubface ROC through impact from swing-to-swing.
Jeff.
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janik
Full Member
Posts: 143
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Post by janik on Jan 10, 2022 4:24:46 GMT -5
Hi Dr. Mann,
While I can’t debate the merits of converting a student from DH to non-DH and vice versa, I do notice that Jim allows the wrists to break after P7 in his full swing, whereas he holds on in his mini practice swings (which is what you are calling DHing). Logically, it is obvious to me that this ‘holding on’ action will slow down his club speed unless his entire torso can keep up (highly unlikely except for high level athletes). I think Kwon was merely noticing how inhibited and well, awkward, his follow through in slow swings was.
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Post by imperfectgolfer on Jan 10, 2022 8:37:31 GMT -5
Hi Dr. Mann, While I can’t debate the merits of converting a student from DH to non-DH and vice versa, I do notice that Jim allows the wrists to break after P7 in his full swing, whereas he holds on in his mini practice swings (which is what you are calling DHing). Logically, it is obvious to me that this ‘holding on’ action will slow down his club speed unless his entire torso can keep up (highly unlikely except for high level athletes). I think Kwon was merely noticing how inhibited and well, awkward, his follow through in slow swings was. I think that if one uses a DH-hand release action that it will look awkward in a mini-swing where one abruptly stops at P7.5, and it will give the impression that the golf swing is being inhibited. However, it will not look awkward in a full swing because the golfer will start to supinate the lead forearm after P7.4 as he directs the club up-plane in the later followthrough. Also, this "holding-action" will only slow the clubhead down through impact in a mini-swing, but not in a full swing action. This student-golfer - Jim Sheridan - can rotate his pelvis/torso extremely well through impact into his followthrough so there should be no reason why he should not be able to generate high clubhead speeds at impact. It is a fallacy to believe that using a DH-hand release action will result in a slower clubhead speed at impact if the golfer is very athletic and flexible - Bryson DeChambeau, Dustin Johnson, Justin Thomas, Collin Morikawa, Cameron Champ and Jon Rahm are all long hitters despite using a DH-hand release action for their driver swing action. By the way, I cannot see any evidence that Jim Sheridan is allowing his wrists to break down after P7 in his full swing action, and I think that it only happens after P7.2. Between P7 => P7.2 his clubshaft is traveling at roughly the same angular velocity as his lead arm and it does not bypass his lead arm (from an angular rotational perspective).
Jeff.
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janik
Full Member
Posts: 143
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Post by janik on Jan 10, 2022 8:59:51 GMT -5
Hi again, Dr. Mann,
You said: "I think that if one uses a DH-hand release action that it will look awkward in a mini-swing where one abruptly stops at P7.5, and it will give the impression that the golf swing is being inhibited. However, it will not look awkward in a full swing because the golfer will start to supinate the lead forearm after P7.4 as he directs the club up-plane in the later followthrough."
However I can clearly see Jim is performing this 'holding-on' action all the way to P8 in his mini swings (see app. 39:45 in the video). Maybe this is his practice 'feel' to achieve the DH action, which just lasts until P7.2 as he can't keep up to P8?
Also; "By the way, I cannot see any evidence that Jim Sheridan is allowing his wrists to break down after P7 in his full swing action, and I think that it only happens after P7.2. Between P7 => P7.2 his clubshaft is traveling at roughly the same angular velocity as his lead arm and it does not bypass his lead arm (from an angular rotational perspective)."
I agree that it happens at about P7.2, I merely meant after P7 to being generally after impact, P7.2 is more specific.
Janik
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