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Post by chipitin on Oct 8, 2013 0:22:14 GMT -5
Chipitin, This is your quote from the SMK paper-: "T he optimization algorithm found the muscle coordination pattern that resulted in the highest clubhead speed at impact while also ensuring the clubface was square to the target line. The clubhead speed for Sim3 (44.1 m/s) was 22% higher than that generated during Sim1 (36.2 m/s), which indicates as to how much active rotation of the forearm from a muscular torque can contribute to clubhead speed." You are trying to claim that active muscular torque forces causing the active release of PA#3 increases clubhead speed at impact. However, you have not really understood the paper - because he states very clearly that the optimization algorithm had to achieve two goals simultaneously i) maximize clubhead speed and also ii) achieve a square clubface at impact. It is obvious that a golfer will have to slow down his clubhead speed (due to the sequential release of PA#4 => PA#2) if doesn't use any active release of PA#3 - presuming that he wants to have a square clubface at impact. If he actively releases PA#3 then he can swing faster - because he can then more likely achieve a square clubface at impact even if he releases PA#4 => PA#2 faster. In other words, SMK's computer modelling put constraints on a passive PA#3 release (Sim 1) by imposing a penalty - in the paper, SMK specifically stated that-: " Penalties were also incurred if the model was not in a proper position at impact, such as having the clubface misaligned with the target For example, the penalty for a misaligned clubface was calculated using an expression (penalty = [2x misaligment] that reduced the objective function by 4 m/s if the clubface was misaligned by 1 degree". In other words, Sim 1 was deliberately penalized relative to Sim 3 in SMK's theoretical experiment. Here again is SMK's graph. This SMK graph clearly shows that an optimum swing action requires a large amount of M arm torque to actively release PA#3 in the optimum manner so that the clubface becomes square by impact - but that minimal M wrist torque is needed to optimally release PA#2. It is obviously possible to use more M wrist force (positive wrist torque - as recommended by BM), but SMK has shown that it is not necessary/advantageous. You also quoted Drewyallop, a BM groupie, who is clueless! He wrote-: " At this point two alternatives were tested.
In the first case the golfer immediately applies forearm supination torque. In the second case forearm supination torque is applied mid-swing i.e. when lead forearm is parallel to ground (the magic position).
Early supination was found to be sub-optimum. Applying supination torque at the start of the downswing results in something like premature ejaculation. The work stops before the job is done. Angular momentum increases very quickly at the start of the downswing but quickly peters out to nothing before mid-swing is reached (MikeG may want to provide a graphic showing the peter-out effect)." That's pure BS! Applying left forearm supination torque at the start of the downswing cannot work because it throws the clubshaft over-the-plane (tumble action) and SMK showed that it is counterproductive to have the clubshaft move over-the-plane. It has nothing to do with Drew's idea that "angular momentum is petering-out by the mid-downswing". The only appropriate time to apply M arm torque to release PA#3 is to start at P5.5-P6 and then increase the degree of M arm torque progressively during the remainder of the late downswing. As SMK's graph shows M arm torque must be applied for a considerable time period before any Q arm angular rmotion becomes apparent (mainly between P6.5 and P7). Jeff. It's not my quote! It's from Sasho's paper. I just highlighted that part as I know you would find a problem with it and I was right. You are also confusing beta torque/thru the plane with gamma/supination torque in your critique of DREW'S COMMENTS. Supination/ gamma torque is not the tumble action , Beta torque thru the plane is the tumble action ala reverse/negative tumble and positive beta torque tumble. Gamma torque is like Manzella's twist away it prevents an open face and many golfers apply it at different points of the d.s. including sooner than you think. That's the same mistake Tapio made in his ridiculous demo video of supination, what he showed was early beta torque, not early supination/gamma torque.
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Post by imperfectgolfer on Oct 8, 2013 0:41:02 GMT -5
Chipitin, You wrote-: " Supination/ gamma torque is not the tumble action , Beta torque thru the plane is the tumble action ala reverse/negative tumble and positive beta torque tumble." It is you who is confused. What do you think produces the beta torque in a tumble action when the club is at the P5 to P5.5 position - as demonstrated in this image of BM performing a tumble action? perfectgolfswingreview.net/ManzellaTumble.jpg [/img] It is obviously due to a counterclockwise rotation of the left forearm (which is left forearm supination) - look at the radial border of the left lower forearm relative to the left antecubital fossa, and you can clearly see that he is supinating his left forearm in order to tumble the clubshaft over-the-plane. Left forearm supination only produces a "pure" gamma torque in the late downswing when the clubshaft is straight-line-aligned with the left arm. You also wrote-: " Gamma torque is like Manzella's twist away it prevents an open face and many golfers apply it at different points of the d.s. including sooner than you think." Twistaway is not due to left forearm supination. It is due to active left wrist palmar flexion and its associated finger-torquing action when the clubshaft is constrained from angulating in response to an active/forced left wrist palmar flexion action. It can occur at ~P5.5-P6 and it automatically dissipates by P6.5 when the left wrist moves from radial deviation to ulnar deviation. Jeff.
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Post by chipitin on Oct 8, 2013 0:47:31 GMT -5
No I'm right you can apply gamma torque without tipping the shaft over, you have to know how to apply it. The tumble action is tipping the shaft over thru the plane and is rotating the whole arm. If you look at twistaway/gamma torque it is not tipping the shaft thru the plane.
It is just the rotation of the wrists and lower forearm which points the palm of the right hand away from the target and flattens the lead wrist and thus eliminates an open face.
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Post by imperfectgolfer on Oct 8, 2013 0:55:34 GMT -5
Chipitin,
Wrong again!
You wrote regarding a twistaway action-: "It is just the rotation of the wrists and lower forearm which points the palm of the right hand away from the target and flattens the lead wrist and thus eliminates an open face."
Twistaway doesn't primarily involve a rotary motion of the left wrist because the left wrist cannot independently rotate, and it is primarily secondary to an active/forced left wrist palmar flexion motion (which is a left wrist hinging motion and not a left forearm rotary motion). During the twistaway maneuver, the club gets torqued around its longitudinal axis (gamma torque) by the clasping fingers. The flattening of the left wrist is due to left wrist palmar flexion, and not due to left forearm rotation, which doesn't affect the alignment of the left wrist.
You also wrote-: "The tumble action is tipping the shaft over thru the plane and is rotating the whole arm."
Wrong again!
Note that BM's left humerus doesn't externally rotate during his tumble action. The alignment of his left antecubital fossa doesn't change during his tumble action.
Jeff.
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Post by chipitin on Oct 8, 2013 0:55:34 GMT -5
twisting of the grip along the axis of the shaft (gamma)
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Post by chipitin on Oct 8, 2013 1:01:30 GMT -5
Chipitin, Wrong again! You wrote regarding a twistaway action-: " It is just the rotation of the wrists and lower forearm which points the palm of the right hand away from the target and flattens the lead wrist and thus eliminates an open face." Twistaway doesn't primarily involve a rotary motion of the left wrist because the left wrist cannot independently rotate, and it is primarily secondary to an active/forced left wrist palmar flexion motion (which is a left wrist hinging motion and not a left forearm rotary motion). The flattening of the left wrist is due to left wrist palmar flexion, and not due to left forearm rotation, which doesn't affect the alignment of the left wrist. Jeff. I just have to disagree it is a combination move which INCLUDES A TWISTING OF THE GRIP END Tapio didn't understand this either it isn't pure P.F. Pure P.F. would be beta thru the plane.
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Post by chipitin on Oct 8, 2013 1:06:27 GMT -5
Pure P.F. is beta thru the plane the reverse tumble the laying off of the shaft like in Sasho's video.
Twistaway includes both P.F. and Gamma.
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Post by imperfectgolfer on Oct 8, 2013 1:09:18 GMT -5
Chipitin,
You wrote-: "I just have to disagree it is a combination move which INCLUDES A TWISTING OF THE GRIP END Tapio didn't understand this either it isn't pure P.F."
I agree with your capital-letter comments. The twisting of the grip is due to the muscular activity of the flexor digitorum muscles to the 2nd, 3rd, 4th and 5th fingers, and which is also responsible for secondarily palmar flexing the left wrist. In an active/forced left wrist palmar flexion motion (twistaway maneuver) performed when the wrist is radially deviated and when one is holding a rounded grip, one primarily uses the flexor digitorum muscles to palmar flex the left wrist and not the left wrist palm flexor muscles (flexor carpi radialis and flexor carpi ulnaris).
You also wrote-: "Pure P.F. would be beta thru the plane".
That's only true if the club is allowed to angulate and if it is not constrained by the RFFW's aligment relative to the LAFW.
Jeff.
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Post by chipitin on Oct 8, 2013 1:11:22 GMT -5
O.K. I can live with that.
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Post by imperfectgolfer on Oct 8, 2013 1:19:33 GMT -5
Chipitin, You wrote-: " Pure P.F. is beta thru the plane the reverse tumble the laying off of the shaft like in Sasho's video.". I disagree 100%. When one shallows the clubshaft (= performing a reverse tumble action) while maintaining an intact LAFW/FLW, the entire LAFW rotates to a shallower plane. It is the exact reverse of BM's tumble action when the entire LAFW rotates to a steeper plane. Note that BM's left wrist remains geometrically flat during his tumble action and the clubshaft remains straight-line-aligned with the radial border of his left lower forearm during his tumble action. Jeff.
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Post by chipitin on Oct 8, 2013 1:29:37 GMT -5
Thats because he isn't letting the reverse tumble flatten his wrist so he isn't doing P.F. but he could if he wanted to, one can let the weight of the clubhead fall onto the right hand and if you have supple relaxed wrists the lead wrist can flatten along with the shaft and have a bowed/p.f. wrist without any twisting/gamma. Then you have pure P.F. thru the plane
One can choose what one want's to do.
Tapio never understood this among other things.
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Post by chipitin on Oct 8, 2013 3:17:11 GMT -5
Think about this, when Hogan described how he supinated his wrist and showed a raised wrist bone in his book 5l, what he felt was a twisting /gamma torque and P.F. that at the time point he did it he did the combination move of gamma and p.f. and that made his wrist bowed from cupped and at the same time he was supinating.
Tapio never understood this and made a big deal about how Hogan was wrong in the labelling of the raised wrist as supination and not p.f. but in fact it was both
Hogan felt the supination/gamma action and he also felt the P.F. of the wrist a combination move ,he probably felt the P.F. bowing more( just a guess) so he labelled it as all supination of the wrist.
Which is wrong, but Hogan was right that he was supinating and Tapio is wrong that it was just a pure P.F. move and that Hogan never did supination.
Anyways that's my opinion on it.
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Post by imperfectgolfer on Oct 8, 2013 10:29:44 GMT -5
Chipitin, You wrote-: " Thats because he isn't letting the reverse tumble flatten his wrist so he isn't doing P.F. but he could if he wanted to, one can let the weight of the clubhead fall onto the right hand and if you have supple relaxed wrists the lead wrist can flatten along with the shaft and have a bowed/p.f. wrist without any twisting/gamma. Then you have pure P.F. thru the plane." I disagree 100% with your reasoning. A golfer who has the RFFW correctly applied to the back of the grip (and therefore the intact LAFW) during a reverse tumble motion will not allow the clubshaft to droop (thus producing left wrist palmar flexion) by allowing the right wrist to increasingly dorsiflex. Why should a golfer change the degree of right wrist bending during a reverse tumble action, which happens during the power package slotting phase? The golfer who is particularly noted for performing a reverse tumble action in the early downswing is Sergio Garcia, but he still maintains an intact LAFW/FLW during the process. SG is exhibiting his classic clubshaft shallowing move between P4 and P5 - and you can see that he maintains an intact LAFW (clubshaft is straight-line-aligned with his left arm) and FLW during his clubshaft shallowing action. You also wrote-: " Think about this, when Hogan described how he supinated his wrist and showed a raised wrist bone in his book 5l, what he felt was a twisting /gamma torque and P.F. that at the time point he did it he did the combination move of gamma and p.f. and that made his wrist bowed from cupped and at the same time he was supinating. ---- Hogan was right that he was supinating and Tapio is wrong that it was just a pure P.F. move and that Hogan never did supination. I have no idea why you believe that Hogan had a twisting gamma torque sensation through impact - simply because his left wrist was palmar flexed. He was wrong to label that classic image showing a raised wrist bone in his book as representing supination, but he was obviously supinating his left forearm pre-impact (during his PA#3 release action between P6.5 and P7) to get to that left wrist impact alignment. Hogan was obviously supinating his left forearm between image 2 and image 4. Jeff.
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Post by chipitin on Oct 8, 2013 11:38:51 GMT -5
I disagree 100% with your reasoning. A golfer who has the RFFW correctly applied to the back of the grip (and therefore the intact LAFW) during a reverse tumble motion will not allow the clubshaft to droop (thus producing left wrist palmar flexion) by allowing the right wrist to increasingly dorsiflex. Why should a golfer change the degree of right wrist bending during a reverse tumble action, which happens during the power package slotting phase? The golfer who is particularly noted for performing a reverse tumble action in the early downswing is Sergio Garcia, but he still maintains an intact LAFW/FLW during the process. There are different ways to accomplish things. There is no rigid written in stone way of doing a swing, there are options, that by now should be obvious. You always want to know why someone would do things different than your idea of things, it's because there is no particular way, people are different and feel things differently we have an ability to adjust things to our own style and still accomplish a task. And it does not appear in a video as a shaft droop because there is no shaft droop, it looks exactly the same as your example. I know because I do this in my swing. It does flatten the shaft/ reverse tumble. That is pure P.F. with no twisting! What's nice about it is you can really feel the clubhead and how it falls back taking the shaft with it. And it helps maintain some shaft lean later in the d.s. because of the increased right wrist bend so you can apply the wrist extension and not hold on and "drive hold" ! The right wrist is going from bent to flattening in the d.s. of a full swing that is a fact unless you try and stop it from doing so for a certain shot.
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Post by chipitin on Oct 8, 2013 11:52:05 GMT -5
I have no idea why you believe that Hogan had a twisting gamma torque sensation through impact - simply because his left wrist was palmar flexed. He was wrong to label that classic image showing a raised wrist bone in his book as representing supination, but he was obviously supinating his left forearm pre-impact (during his PA#3 release action between P6.5 and P7) to get to that left wrist impact alignment. I never said through impact. If Hogan did pure P.F. and no gamma how do you explain his clubface angle in a more closed/less open position especially if he hasn't done any early supination and pure P.F. doesn't alter the face angle? Since Hogan has a cupped lead wrist part way down in the d.s. he can't do pure P.F. it's not possible, anyone can try and do pure P.F. from a cupped wrist at the point Hogan was doing the combination gamma/p.f. and you will find you cannot do pure P.F. and you have to do a combination of Gamma and P.F. The shaft will not angle back like it does in pure P.F. Hogan already did that WITH THE RIGHT WRIST BEND IN THE B.S. All the pieces are there. Look at your example of Manzella, you said he doesn't flatten his lead wrist and p.f. when he does the beta torque/reverse tumble, that's correct.... same as Hogan as one can see Hogan still has a cup in his lead wrist after that point, then it goes to a flattened or even bowed position later and the shaft does not angle back as it would if you did pure P.F. THE ANGLED BACK SHAFT IS FROM THE BENT RIGHT WRIST HOGAN CREATED IN THE B.S. It has a certain amount of radial deviation in it also. he isn't doing pure P.F. BUT A COMBINATION OF GAMMA/P.F./BETA. U.D. That's not even taking into account the secondary axis tilt/ side bends etc. At 14:18 of the video below.
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