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Post by dubiousgolfer on Feb 7, 2024 20:16:28 GMT -5
I was reading another research article titled : An Insight Into the Importance of Wrist Torque in Driving the Golfball (by Eric J Sprigings and Robert J Neal)
people.stfx.ca/smackenz/courses/DirectedStudy/Articles/Sprigings%202000%20Insight%20into%20the%20important%20of%20wrist%20torque.pdf
They used a forward dynamics model swing and found a timed muscular wrist uncocking (radial-ulnar deviation) added after MOF release, can increase clubhead speed by 9%. In the model, the active wrist uncocking occurred when its arm segment was 30 degrees below a horizontal line drawn though the shoulder joint. If you time it too early or late it can lessen your clubhead speed (ie. less than the clubhead speed if no active wrist torque applied). If you look at the model , there is no forearm rotation and the swing is planar with the wrist joint only capable of radial/ulnar deviation. The swing with the wrist torque generator activated showed an increase in clubhead speed of 8 mph vs swing that just used MOF release (without any added active wrist torque). Further, the model was validated against 2D images of Nick Faldo's swing. Now the confusing aspect for me is that the graph shows positive wrist torque at impact which seems to contradict what Dave Tutelman said about the wrists not being able to keep up with the angular velocity of the club, which therefore applies a negative torque. There is no mention in the article whether the shaft was in forward or backward bend approaching impact. Considering there is no forearm rotation , the only golfers that I thought could mimic this type of model swing would be golfers with very strong grips (like those used by Brendan Steele or David Duval) but does this mean positive wrist torque at impact is a possibility in a full driver swing? I'll post a few graphs a little later into this post. DG
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Post by dubiousgolfer on Feb 8, 2024 8:49:26 GMT -5
I've decided not to post any graphs for this thread as I think these forward dynamic models are producing more questions (regarding their integrity) vs their usefulness in providing any detailed insight about what is happening in the golf swing.
For example, in both Dr Sasho Mackenzie's and Sprigings & Neal models they show active wrist torque maxing at about 20 -25 Nm, but human studies on males show max torques about 9-10 Nm.
DG
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Post by imperfectgolfer on Feb 8, 2024 10:21:45 GMT -5
I was reading another research article titled : An Insight Into the Importance of Wrist Torque in Driving the Golfball (by Eric J Sprigings and Robert J Neal)
people.stfx.ca/smackenz/courses/DirectedStudy/Articles/Sprigings%202000%20Insight%20into%20the%20important%20of%20wrist%20torque.pdf
They used a forward dynamics model swing and found a timed muscular wrist uncocking (radial-ulnar deviation) added after MOF release, can increase clubhead speed by 9%. In the model, the active wrist uncocking occurred when its arm segment was 30 degrees below a horizontal line drawn though the shoulder joint. If you time it too early or late it can lessen your clubhead speed (ie. less than the clubhead speed if no active wrist torque applied). If you look at the model , there is no forearm rotation and the swing is planar with the wrist joint only capable of radial/ulnar deviation. The swing with the wrist torque generator activated showed an increase in clubhead speed of 8 mph vs swing that just used MOF release (without any added active wrist torque). Further, the model was validated against 2D images of Nick Faldo's swing. Now the confusing aspect for me is that the graph shows positive wrist torque at impact which seems to contradict what Dave Tutelman said about the wrists not being able to keep up with the angular velocity of the club, which therefore applies a negative torque. There is no mention in the article whether the shaft was in forward or backward bend approaching impact. Considering there is no forearm rotation , the only golfers that I thought could mimic this type of model swing would be golfers with very strong grips (like those used by Brendan Steele or David Duval) but does this mean positive wrist torque at impact is a possibility in a full driver swing? I'll post a few graphs a little later into this post. DG I have been studying golf swing biomechanics for ~16 years and my opinions regarding factors affecting the release of PA#2 has changed over the years. I now believe that it is likely impossible for a pro golfer to deliberately/consciously perform an active lead wrist uncocking action during the downswing when performing a full golf swing action eg. driver golf swing.
Here is Dustin Johnson's driver swing action.
The red splined path is his hand arc path.
Rob Neal/SMK seem to theorise that an active lead wrist uncocking action (involving the active muscular contraction of lead forearm muscles) happens between P5 (image 2) => P5.5 (image 3). However, I cannot see DJ doing anything actively during that time period that would suggest that he is deliberately/consciously uncocking his lead wrist using the active muscular contraction of lead forearm muscles. I do agree that DJ is starting to release PA#2 between P5 => P5.5, but I think that it is due to the interplay between the changing MOF/hand couple torques in play during that time period combined with the effect of a straightening trail elbow.
Jeff.
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Post by dubiousgolfer on Feb 9, 2024 12:39:21 GMT -5
Dr Mann
On reflection , and wondering why they set the model's wrist torque to such a large maximum value 60 Nm, way above the capability of a human male, I think it was there to cater for the effect of a missing trail arm. If a golfer wanted to actively create a positive torque with the assistance of a trail arm , I suspect it would be like an assertive straightening of the trail elbow such that the trail hand applied a force below the coupling point.
Because their model couldn't recreate that type of force across the shaft and was restricted to lead arm, they had no real choice but to use active wrist torque instead to replicate that same effect (even though it was an impossible for a human golfer).
I couldn't imagine a pro golfer trying to perfectly time a positive torque as mentioned in that research article.
Wouldn't this type of technique be similar to swing-hitting?
DG
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Post by imperfectgolfer on Feb 9, 2024 13:21:00 GMT -5
Dr Mann On reflection , and wondering why they set the model's wrist torque to such a large maximum value 60 Nm, way above the capability of a human male, I think it was there to cater for the effect of a missing trail arm. If a golfer wanted to actively create a positive torque with the assistance of a trail arm , I suspect it would be like an assertive straightening of the trail elbow such that the trail hand applied a force below the coupling point. Because their model couldn't recreate that type of force across the shaft and was restricted to lead arm, they had no real choice but to use active wrist torque instead to replicate that same effect (even though it was an impossible for a human golfer). I couldn't imagine a pro golfer trying to perfectly time a positive torque as mentioned in that research article. Wouldn't this type of technique be similar to swing-hitting? DG I have no "idea" what golf instructional message you are trying to convey! Jeff.
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Post by dubiousgolfer on Feb 9, 2024 13:53:37 GMT -5
It's of no importance , just trying to make some sense as to why they gave the model such a high wrist torque capability.
DG
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