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Post by imperfectgolfer on Jul 28, 2012 7:41:23 GMT -5
See this thread on Jeffy's forum jeffygolf.com/showthread.php?408-A-small-but-critical-differenceJeffy posted this comparative photo of his "before" and "after" swing. jeffygolf.com/attachment.php?attachmentid=1088&d=1343308602 [/img] In the "after" swing one can see that his clubface is slightly more closed to the clubhead arc, and Jeffy states that it is due to-: "The changes I wanted to highlight, though, were in the forearms and wrists, what I call "Impact Snap Device" hands. On the left, you can see some cup in the left wrist and a pronated left forearm. On the right, the left wrist has flattened due to a little earlier left forearm supination and bowing (or palmar flexion) of the left wrist". My question - what is the purpose of performing that type of move as one reaches the P6 position? I cannot understand why a golfer would want to close the clubface slightly at that time point when he is going to close the clubface to the clubhead arc by releasing PA#3 which happens between P6.5 and P7. Here is Jeffy at P6.7. Note that the back of his FLW and lower forearm is angled relative to the ball-target line and that the clubface is open to the clubhead arc to roughly the same degree in the "before" and "after" swings. From that time point, he is going to square the clubface by impact by supinating his left forearm (which is the primary biomechanical mechanism underlying the release of PA#3). Here is his FLW/left forearm supinatory alignment at impact. One can see that he squared the clubface between P6.7 and P7 by releasing PA#3 - to the same degree in his "before" and "after" swings. So, what is the purpose of trying to close the clubface to the clubhead arc as one bypasses the P6 position by deliberately palmar flexing the left wrist - considering the fact that his left wrist is not arched/bowed at impact? Jeff.
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Post by tomdavis76 on Jul 28, 2012 12:46:14 GMT -5
There is more cup in the left wrist at impact in the before, and the face closed over more, so I was hooking a lot at that time.
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Post by imperfectgolfer on Jul 28, 2012 13:48:57 GMT -5
I cannot see any more cup in your left wrist at impact in the "before" swing. How can that be possible if the clubshaft and left arm are in a straight line at low point - in both the "before" and "after" swing? If the ball is placed at low point, then one has to have a GFLW at low point (presuming a neutral-to-slightly strong left hand grip). A bowed left wrist will exist when one places the ball behind low point - and the degree of bowing depends on the degree of forward shaft lean at impact.
I still cannot understand how bowing the left wrist at P6 in order to slightly close the clubface (relative to the clubhead arc) will change the impact alignments, or how it can be of benefit to a golfer who uses PA#3 to square the clubface. I can certainly understand that bowing can occur between P6 and P7 if one leads actively with one's lead wrist - against the resistance of a lagging clubhead. However, the bowing is simply an end-product of leading with the FLW (against the inertia of a lagging club) and the amount of bowing that exists at impact depends on the degree of forward shaft lean at impact.
Jeff.
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Post by imperfectgolfer on Jul 28, 2012 18:03:39 GMT -5
Jeffy,
I see that you wrote the following in a post in the Jeffy golf forum -: "If by supinating the left forearm sufficiently early in the downswing, so that the clubface is actually slightly closed to what is desired at impact, the left forearm can actually pronate a bit through impact."
I think that you have no "evidence" that this pronation phenomenon is happening through impact. I think that if one closes the clubface earlier (as you demonstrate in your iron swing) - which is due to actively curling the fingers and torquing the grip end of the club, which in turn produces left palmar flexion and a small degree of left forearm supination, then one can have a square clubface at impact while having a small degree of forward shaft lean. Under normal circumstances, if one has forward shaft lean of the club at impact due to left palmar flexion that causes angulation of the club backwards (away from the target) that angulation would open the clubface slightly. Actively flexing the fingers (using the flexor digitorum muscles) in order to produce left palmar flexion will slightly close the clubface to the clubhead arc and allow the clubface to be square at impact despite having forward shaft lean. That would be useful with iron shots.
Jeff.
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Post by tomdavis76 on Jul 28, 2012 20:34:59 GMT -5
I cannot see any more cup in your left wrist at impact in the "before" swing. Can you see it now?
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Post by imperfectgolfer on Jul 29, 2012 0:16:48 GMT -5
Jeffy,
All you are showing is that the capture image of the "before" swing showed a small degree of flipping while in the "after" swing the LAFW remains intact after impact. What has that got to do with your P6 position - where the clubface is slightly more closed to the clubhead arc in the "after" swing? Also, what different biomechanical maneuver do you perceive that you are using in the "after" swing that would produce a slightly closed clubface at P6 and a greater likleihood of maintaining an intact LAFW through impact?
Jeff.
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Post by tomdavis76 on Jul 29, 2012 8:09:25 GMT -5
Jeffy, All you are showing is that the capture image of the "before" swing showed a small degree of flipping while in the "after" swing the LAFW remains intact after impact. What has that got to do with your P6 position - where the clubface is slightly more closed to the clubhead arc in the "after" swing? Uh, everything. You know, cause and effect. Didn't I explain that in the thread? Look again, then ask clarifying questions, if need be.
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Post by tomdavis76 on Jul 29, 2012 8:22:04 GMT -5
Jeffy, I see that you wrote the following in a post in the Jeffy golf forum -: "If by supinating the left forearm sufficiently early in the downswing, so that the clubface is actually slightly closed to what is desired at impact, the left forearm can actually pronate a bit through impact." I think that you have no "evidence" that this pronation phenomenon is happening through impact.Let me put it this way; in the pictures below, to get from the position on the left to the one on the right, some palmar flexion of the left wrist and a small amount of supination of the left forearm is required, don't you agree? So, to go from the position on the right to the position on the left, the left wrist would need to dorsiflex or extend some and the left forearm would need to pronate a bit, right? jeffygolf.com/attachment.php?attachmentid=1088&d=1343308602 [/img] So, if the player "flips" through impact, like this, shouldn't the left forearm be pronating a bit?: I initiate the movements in the wrists and forearms, not the fingers particularly. Maintaining a relaxed, constant grip pressure seems to work best.
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Post by imperfectgolfer on Jul 29, 2012 18:50:19 GMT -5
Jeffy,
You wrote-: "Uh, everything. You know, cause and effect."
I perceive that answer to be an avoidance tactic - where you are avoiding explaining the biomechanics of your postulated "cause-and-effect" relationship.
You also wrote with respect to the Hogan animated gif.
"So, if the player "flips" through impact, like this, shouldn't the left forearm be pronating a bit?"
Why?
Regarding the Hogan animated gif - where do you see any left forearm pronation happening? If I look at the dorsum of his lower left forearm (where the watchface would be situated), that "area" is rotating counterclockwise through impact, and that is the opposite direction to what one would expect with left forearm pronation. I think that it is difficult to quantify how much of the counterclockwise rotation is due to counterclockwise rotation of the left forearm (supination) and how much is due to external rotation of the left humerus. I think that there is secondary "evidence" that supports the "visual evidence" that there is counterclockwise rotation of the left forearm - and that is the fact that the right forearm is visually pronating while the right elbow straightens.
Jeff.
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Post by tomdavis76 on Jul 29, 2012 19:27:25 GMT -5
Jeffy, You wrote-: "Uh, everything. You know, cause and effect." I perceive that answer to be an avoidance tactic - where you are avoiding explaining the biomechanics of your postulated "cause-and-effect" relationship. Yes, I'm avoiding repeating myself by responding to "questions" you pose that have been answered many times already. Well, I didn't say it was easy to see in 2D. But, I don't know how a player can flip through impact without pronating the left forearm. That said, I'm willing to listen to any explanation you have to offer.
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Post by imperfectgolfer on Jul 30, 2012 6:43:53 GMT -5
Jeffy, You wrote-: " But, I don't know how a player can flip through impact without pronating the left forearm". I don't know why you harbor that belief. Flipping is due to left wrist dorsiflexion and the left wrist merely bends back. It is a wrist motion and not a forearm motion. If there is any forearm motion happening at the same time, then it is likely to be a roller action where the left forearm rotates counterclockwise (which is supination). I think that a frequent cause of flipping is active straightening of the right wrist through impact and that can cause left wrist bending without producing any left forearm motion (other than some secondary left forearm supination if the right palm also applies a rotary torque force against PP#1). This golfer is flipping through impact - without any pronatory forearm rotary motion. Regarding the Hogan photo, you wrote-: "Well, I didn't say it was easy to see in 2D." I think that it is easy to see that his left lower forearm is rotating counterclockwise, and not clockwise, in this animated gif. I think that the back of his left hand and lower forearm area (watchface area) are rotating counterclockwise to the same degree between P6.8 and P7.2. Also, note that the clubface is remaining essentially square to the clubhead arc between P6.8 and P7.2 - and considering the fact that the clubhead arc is circular in shape, then that means that the clubhead must be rotating counterclockwise to remain square to the clubhead arc. Jeff.
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