Is a convex shape shaft strike on the ball probable?

KZG Golf

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I wish to post an idea on the above topic and invite comments and feedback.

I have watched the swings of many professionals on youtube. I noticed that the shaft of the club assumes a concave shape before the clubhead impacts the ball. It soon prompted me to wonder why this should be so.

After all, the shaft has a convex shape when the left arm is at 9 to 8 o’clock position. Why does it not stay that way? Why must it transition to straight before it assumes the concave shape before it strikes the ball?

Most of us intuitively know that the convex shape is a strong shape. If the objective is to drive the ball as long we can, the convex shape should be preferred. So, what is causing the shaft to lose its convex shape?

When that thought occurred to me, I started to think about it and actively looked for the reasons why the transition happened with all the swings that I have watched in slow motion (thanks to modern video technology).

Is it caused by the downswing slowing down? And if so, what are the factors causing the deceleration through the impact zone? When I got thinking in that direction, two features of the modern swing occurred to me.

The shoulder-width stance that most golfers used, including Rory McIlroy, has always occurred to me to be too wide for efficient motion. Hogan has always emphasized that the downswing must be as fast as possible. For that reason, he advocated a lateral slide before turning the left hip onto the left heel. But that movement over a wide stance is hard to do for many golfers.

To tackle that problem, Mindy Blake in his Golf Swing of the Future book proposed a much narrower stance. This fits Blake’s idea of using the legs as the dominant power source. Like Blake, I drew on the experience of field sports. The dominant source of the power of field sports is the rotational movement of the lower body. I noticed that the final swing movement of the hammer throw or shot put is done over a narrow stance. But it is wider than Blake’s.

So, I deduced that a stance in between Hogan and Blake seems logical. A stance in between should allow the rotational movement of the lower body to express its full power potential. The rotational movement of the lower body over a narrow stance can overcome the issue of the loss of momentum in the downswing. This movement is superior to that of the lateral slide and then turn movement advocated by Hogan.

What else might be causing the downswing to decelerate throughout the impact zone before the shaft strikes the ball? I have noticed that many long drivers of the ball ended up with the left foot opening after impact on the ball.

So, I wondered whether the 22 degrees open left foot advocated by Hogan is indeed impeding the downswing. If not, why do long drivers more often than not need to open the left foot in order to finish their swing? Then it occurred to me that opening the left foot at address can only be a good thing. A simulation of a downswing will suggest that a left foot opened to be about 45 degrees is the minimum required for it not to impede the downswing.

In addition, Blake proposed that the right foot be turned towards 10 degrees. This so that the shoulders need to be turned less around the body to obtain short but nevertheless full backswing.

Will these changes be sufficient to allow a professional golfer to retain the convex shape shaft (when the left arm is at the 9 o’clock position) throughout the impact zone? If that can be done, then the convex strike on the ball can be achieved.

But, will it result in longer driving distances? One way of looking at it is to consider the convex tapered end of the fishing rod casting the line. The more convex-bend the shape is, the further the casting. Or consider the convex bend of the pole propelling a vaulter over the bar - the more acute the bend the higher the vaulter goes.

Thus, by analogy, a ‘convex’ strike on the ball should deliver longer drives.

With that, I invite your inputs.
 

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if you're talking about the images where the shaft is bent almost backwards at impact, that isn't really what's happening. it's called rolling shutter effect.
 

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Tutelman has some good stuff on this. It will go way over the heads of most.
 

93civiccpe

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if you're talking about the images where the shaft is bent almost backwards at impact, that isn't really what's happening. it's called rolling shutter effect.
Tutelman has some good stuff on this. It will go way over the heads of most.
What the 2 of these guys said above. I was curious about this as well when I first saw it in slow motion videos and read about this affect. I couldn't explain it to someone else but I do understand that what I see in those videos is not what is actually happening.
 

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I don't know much about the rolling shutter effect. You see this very senior citizen doesn't operate a smartphone camera. I don't have one.
Why the effect work applies with a 'convex' shape and not a 'concave' one? If you have not watched a 'concave' strike on the ball, go an watch one on youtube. Choose any professional golfer'swing. Watch it slo-mo. Like Rory McIlroy's since he is the leading distance leader. So you should be spoilt for choice.
Meanwhile, enjoy the beautiful vaulter. But do notice the convex-bend of the pole. There is no shutter effect unless you took your eyes off it by focussing on the attractive athlete.
 

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mjkladis

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I don't know much about the rolling shutter effect. You see this very senior citizen doesn't operate a smartphone camera. I don't have one.
Why the effect work applies with a 'convex' shape and not a 'concave' one? If you have not watched a 'concave' strike on the ball, go an watch one on youtube. Choose any professional golfer'swing. Watch it slo-mo. Like Rory McIlroy's since he is the leading distance leader. So you should be spoilt for choice.
Meanwhile, enjoy the beautiful vaulter. But do notice the convex-bend of the pole. There is no shutter effect unless you took your eyes off it by focussing on the attractive athlete.
I would figure the shape you see at impact of a golf club is the unloading from the ~200g load at the end of the shaft. The shafts do flex to a concave shape on the downswing but the golf swing causes the head to pass by at impact.

I would think of it sort of like pulling a tree branch and letting it go.

It’s not as crazy on video but some shaft golf club manufacturers have down some studies on what the shaft does
 

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If what you are talking about is that it looks like the shaft is bending the wrong way in pictures as you would expect, the explanation is, it isn’t.




The shaft does not bend that way, it is an illusion shown by the camera because of what is stated above, the rolling shutter effect.
 

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IMO the forward flex of the shaft is cause by centrifugal force moving from the body (sternum) to the clubhead in a swing where the force is moving from inwards to outwards in a time frame of approx 20 milliseconds. Players who cast from the top distort the shaft early and then have to hang on and hold back in order to make reasonable contact. Expert golfers are still accelerating their body well past impact and are distorting the shaft during the second firing of the pelvis about halfway into the downswing.
(The more work the shoulders and wrists have to do past impact the better the swing.)
Through impact the clubhead reacts as if the shaft is a piece of string - the clubhead deflects in the direction the strike occurs in relation to the centre of gravity of the clubhead.
In the wooden shaft era, shafts the were bent and still had life in them were greatly valued.
 
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Hi mjkladis,

First of all, the pole straightens as the vaulter releases it and she goes over the bar. That is not surprising because the pole or any implement must go, out of necessity, from convex to straight before it can get to concave.

I agree the shaft does flex to concave in the downswing before it impacts the ball. Your observation is correct.

But the point that I make is this. How do you get the shaft to stay at convex when the left arm is at 9 o'clock to arrive at impact position before it transitions to straight and then to concave?

Then, as I mentioned in my post, we can achieve the strike on the ball. That is a desirable objective because the convex bend delivers a powerful force when it unbends. Much more so than a concave one.
 

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Hi razaar,

Your observation is helpful. Most golfers tend to cast from the top and the clubhead loses the centrifugal force prematurely.

The better golfers tend to delay that and strike the ball better and further. All professionals still have the convex shaft at 9 o'clock left arm position transitioning to straight and then to concave before it strikes the ball. After the impact on the ball, the shaft stays concave before it straightens as the swing loses speed. But still begs the question, how to you get the shaft to remain in convex-bend from the 9 o'clock position to impact the ball before it straightens again.

Watch the following video slo-mo at 0.25 playback speed and see the action. You can watch others. It is done at 120fps. So the transition of the shaft is evident. Watch this:
 

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Hi mjkladis,

First of all, the pole straightens as the vaulter releases it and she goes over the bar. That is not surprising because the pole or any implement must go, out of necessity, from convex to straight before it can get to concave.

I agree the shaft does flex to concave in the downswing before it impacts the ball. Your observation is correct.

But the point that I make is this. How do you get the shaft to stay at convex when the left arm is at 9 o'clock to arrive at impact position before it transitions to straight and then to concave?

Then, as I mentioned in my post, we can achieve the strike on the ball. That is a desirable objective because the convex bend delivers a powerful force when it unbends. Much more so than a concave one.
That sounds like a casting move. I would take a few swings then on the last swing try to stop at the club being parallel to the ground. Take note of the position of the club head. A face open to the club path will sometimes cause the golfer to release any desirable angles to square the face back to target before impact which would cause the shaft to become concave too early. This all happens very quickly in then swing
 

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That sounds like a casting move. I would take a few swings then on the last swing try to stop at the club being parallel to the ground. Take note of the position of the club head. A face open to the club path will sometimes cause the golfer to release any desirable angles to square the face back to target before impact which would cause the shaft to become concave too early. This all happens very quickly in then swing
Watch this: . Set it at 0.25 play speed and catch all the action.

If you are an amateur like I, you may not have the swing speed to do the convex strike. I have a swing speed of 85 mph. I do a reflex swing as taught by Mindy Blake and grafted to Hogan's method. But I have incorporated the rotary movement of the lower body that are common in fields sports.

Professionals might soon do it.

Coming to your other point, the clubface can be all over the place even if you strike it with a concave-bend shaft. That is why golf is an intriguing game or frustrating one depending on how you look at it.
 

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If what you are talking about is that it looks like the shaft is bending the wrong way in pictures as you would expect, the explanation is, it isn’t.

The shaft does not bend that way, it is an illusion shown by the camera because of what is stated above, the rolling shutter effect.
supersport, I think you should the video: The golfer is Ariya Jutanugarn. Her shaft is convex-bend at 9 o'clock but it transitions to concave-bend just before impact. Both shapes are in the same video. How can you explain one shape convex as being due to a rolling shutter effect and not when it is a concave shape? csf.com
 

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Watch this: . Set it at 0.25 play speed and catch all the action.

If you are an amateur like I, you may not have the swing speed to do the convex strike. I have a swing speed of 85 mph. I do a reflex swing as taught by Mindy Blake and grafted to Hogan's method. But I have incorporated the rotary movement of the lower body that are common in fields sports.

Professionals might soon do it.

Coming to your other point, the clubface can be all over the place even if you strike it with a concave-bend shaft. That is why golf is an intriguing game or frustrating one depending on how you look at it.
One thing to consider, is that no matter how much a player lags or doesn't lag a shaft. No matter how hard or slow they swing, the shaft will 100% of the time be deflecting forward at impact. Kicking forward so to speak. Always always always. So the head at impact will be ahead of the shaft. The percentage of forward kick will change, but it will always be so..

so I guess the answer is no. Not probable or possible.

but I may not understand the question. Too many words.
 
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This is probably a better video of more extreme forces from a long drive.


Long Drive Slo Mo
 

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I'd be interested to hear the thoughts of @JB, @Jman, or any of the others who are more versed in shaft characteristics and swing dynamics.
 

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One thing to consider, is that no matter how much a player lags or doesn't lag a shaft. No matter how hard or slow they swing, the shaft will 100% of the time be deflecting forward at impact. Kicking forward so to speak. Always always always. So the head at impact will be ahead of the shaft. The percentage of forward kick will change, but it will always be so..

so I guess the answer is no. Not probable or possible.

but I may not understand the question. Too many words.
Hi NVGOLFER80, Thank you for going through the lengthy prose. I needed to explain the basis of the new concept that I was proposing. Anything less would not be fair to the readers to figure out the answer to my question.

There are two points that I wish to make on your observations. One, there are two ways to bend a shaft - a concave-bend and a convex-bend. A convex-bend shaft, on unbending, will reinforce the forward movement of the swing, thereby adding to the power in the swing. A concave-bend, on unbending, will have the clubhead 'recoiling' when it and the shaft move forward.

Two, the point about the 'convex' strike is that the bend, by the very nature of the bend, can stay ahead of the clubhead, if the shaft is dragged forward forcefully enough. So, impacting the ball when the shaft is convex or straightening, it will deliver more force on the ball. You can experience this when you hold a cane in one hand to strike an object like a pillow. Or how the convex-bend pole propels a vaulter over the bar. A 'concave-bend' pole can't do that. I post the photo of the vaulter again.

Even if you are not persuaded by the above, the convex-bend strike will remain a probability because the possibility must exist since the convex bend is the only other way to bend a shaft. And the convex strike is far more powerful. For that reason alone, a system needs to be devised; otherwise, the golf swing will continue to stagnate. (Remember, Rory McIlroy in 2018 drove a mere 14 yards further than John Daly in 1999. And Rory has a better physique, ball, and club.)

If you think it is not possible, we should remember that the US succeeded in doing the previously considered 'impossible' task of landing on the moon. Now, the Chinese have landed in the dark!

And striking the ball with a 'convex-bend' shaft is nowhere near a moon shot. It is just about figuring a system to achieve that. In subsequent posts, I plan to develop the idea for readers to consider. Stay tuned.
 

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I'd be interested to hear the thoughts of @JB, @Jman, or any of the others who are more versed in shaft characteristics and swing dynamics.
There is no doubt that JB Holmes, if he is the golfer you are referring to, can do the convex strike on the ball. But he needs to adopt a new system that I am devising.

It is not about the shaft characteristics but the system that will change the swing dynamics.
 

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Hi NVGOLFER80, Thank you for going through the lengthy prose. I needed to explain the basis of the new concept that I was proposing. Anything less would not be fair to the readers to figure out the answer to my question.

There are two points that I wish to make on your observations. One, there are two ways to bend a shaft - a concave-bend and a convex-bend. A convex-bend shaft, on unbending, will reinforce the forward movement of the swing, thereby adding to the power in the swing. A concave-bend, on unbending, will have the clubhead 'recoiling' when it and the shaft move forward.

Two, the point about the 'convex' strike is that the bend, by the very nature of the bend, can stay ahead of the clubhead, if the shaft is dragged forward forcefully enough. So, impacting the ball when the shaft is convex or straightening, it will deliver more force on the ball. You can experience this when you hold a cane in one hand to strike an object like a pillow. Or how the convex-bend pole propels a vaulter over the bar. A 'concave-bend' pole can't do that. I post the photo of the vaulter again.

Even if you are not persuaded by the above, the convex-bend strike will remain a probability because the possibility must exist since the convex bend is the only other way to bend a shaft. And the convex strike is far more powerful. For that reason alone, a system needs to be devised; otherwise, the golf swing will continue to stagnate. (Remember, Rory McIlroy in 2018 drove a mere 14 yards further than John Daly in 1999. And Rory has a better physique, ball, and club.)

If you think it is not possible, we should remember that the US succeeded in doing the previously considered 'impossible' task of landing on the moon. Now, the Chinese have landed in the dark!

And striking the ball with a 'convex-bend' shaft is nowhere near a moon shot. It is just about figuring a system to achieve that. In subsequent posts, I plan to develop the idea for readers to consider. Stay tuned.
you have to remember that the strike of the ball happens at the bottom of the arc of a circle. The pull vaulter reference is not applicable unless you are talking about when the Athlete is at the very top and is going over the bar. Then the bar is straight.
look at this frame by frame of a pool vaulter. The pole is not still bent as the athlete goes over. It has released and is straight to even moving forward.

1589514359720.jpeg

what I think you are saying is not possible. You can not lean the shaft hard enough to cancel out the forward deflection or kick of a a shaft. You can lesson it but never completely eliminate it. It
 

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you have to remember that the strike of the ball happens at the bottom of the arc of a circle. The pull vaulter reference is not applicable unless you are talking about when the Athlete is at the very top and is going over the bar. Then the bar is straight.
look at this frame by frame of a pool vaulter. The pole is not still bent as the athlete goes over. It has released and is straight to even moving forward.

View attachment 8943271

what I think you are saying is not possible. You can not lean the shaft hard enough to cancel out the forward deflection or kick of a a shaft. You can lesson it but never completely eliminate it. It
NVGOLFER80. I am glad we are looking at the same sport. The first point is that the convex shape is a strong shape. It can propel an athlete. The pole does the transition from convex to straight.
A shaft that is convex-bend transitioning to straight will deliver a greater force on the clubhead than a concave-bend one. I don't think there should be a doubt about that observation.
What is required is to devise a system to get the convex-bend from the left arm at 9 o'clock position to approach and impact the ball with a convex-bend or straightening from a convex-bend?
In subsequent postings, I plan to take my case to readers like you who are prepared to consider the probability of a convex strike on the ball.
I am happy that there are readers out there who have a mind that is open to that probability.
 

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Hi CSF.com

The physics can be complicated and counterintuitive and its best you check these links below :




To summarise:

1. Virtually all Tour Pro Golfers have forward shaft bend as the club approaches impact (from 5 iron-Driver) - actually more than is expected (see further below point 5 for explanation)
2. The clubhead speed is dependent on hand speed and hand path for a swinger (ie. someone who does not use a dominant muscular active torque of the wrists to rotate the club)
3. The 'Release' of the club for a swinger is based on eccentric forces via the arms (ie. the hands being assumed as passive clamps on the grip) across the COM of the club , which cause a 'Moment of Force' and rotates the club's COM to try and align with the 'tail end' of those eccentric forces. Release is the increase in the angle between the lead arm and clubshaft (ie. the uncocking of the lead wrist).
4. The degree of forward shaft bend is not just solely due to 'eccentric forces' . Some people, even Dave Tutelman, seem to use the term 'Centrifugal Force' as a pragmatic description for the 'Release' force , although from a physics perspective the clubhead is not experiencing any outward pulling force.
5. Some of the 'extra' forward shaft bend is due to the fact that the club has reached such a high angular velocity during 'Release' , that the wrist joints are physically incapable of rotating that fast. Therefore the wrist joints and hands are actually now restricting the angular movement of the grip end of the club while the clubhead is still free-wheeling at the peripheral end of the shaft. This is why the shaft has even more forward bend than is normally expected.

Basically , if you are a swinger the club is pulling your hands through impact

6. Other important points to note are:
a. There is not enough time to do anything via your hands (at the grip end) to affect the clubheads motion close to and through impact . Any forces/torque impulses you apply to the grip will take too long for its effect to reach the clubhead for the 0.0004 secs impact period. Therefore the shaft can be assumed to be like a piece of string while the clubhead can be assumed a free moving object through space (ie. when its approaching impact ). I did ask Dave Tutelman where exactly in the downswing path can the shaft be assumed to be acting like a length of string but he didn't have a ready answer.
b. For a driver being swung at 100mph , the dynamic weight of the club at P6 (shaft horizontal in downswing ) will feel like 3 stone weight force, while just before impact it will feel like 7 stone. That is equivalent to swinging a bag of cement , so I can't imagine one being able to increase clubhead speed just using muscular wrist torques.
c. Now this is a really counterintuitive part , but any bend of the shaft 'DOES NOT ROTATE' with the shaft . So even if the golfer rotates the shaft with his arms/forearms , the shaft bend will not rotate with the shaft.

Also , note that Ben Hogan did not laterally slide . In the backswing his right hip moved back and towards the target , it then stabilised in space and he re-rotated his pelvis around the right hip. To someone looking from a face-on view it looks like he has slid his hips targetwards but that is not the case.

The reason why the arms decelerate while the club accelerates is because of Newtons 3rd Law but it applies to 'Torques' too .

"If object A exerts a torque on object B about a given axis, then B exerts an equal but opposite torque on A about the same axis"

So while the arms generate a torque on the club (using eccentric forces through the wrist joints) , the club will apply an equal and opposite torque on the arm (via the wrist joints), therefore the club speeds up while the arms decelerate .

Not sure how all this will help any golfer improve their swings but it might help them identify flawed golf instruction and save their hard earned cash.
 
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Hi CSF.com

The physics can be complicated and counterintuitive and its best you check these links below :




To summarise:

1. Virtually all Tour Pro Golfers have forward shaft bend as the club approaches impact (from 5 iron-Driver) - actually more than is expected (see further below point 5 for explanation)
2. The clubhead speed is dependent on hand speed and hand path for a swinger (ie. someone who does not use a dominant muscular active torque of the wrists to rotate the club)
3. The 'Release' of the club for a swinger is based on eccentric forces via the arms (ie. the hands being assumed as passive clamps on the grip) across the COM of the club , which cause a 'Moment of Force' and rotates the club's COM to try and align with the 'tail end' of those eccentric forces. Release is the increase in the angle between the lead arm and clubshaft (ie. the uncocking of the lead wrist).
4. The degree of forward shaft bend is not just solely due to 'eccentric forces' . Some people, even Dave Tutelman, seem to use the term 'Centrifugal Force' as a pragmatic description for the 'Release' force , although from a physics perspective the clubhead is not experiencing any outward pulling force.
5. Some of the 'extra' forward shaft bend is due to the fact that the club has reached such a high angular velocity during 'Release' , that the wrist joints are physically incapable of rotating that fast. Therefore the wrist joints and hands are actually now restricting the angular movement of the grip end of the club while the clubhead is still free-wheeling at the peripheral end of the shaft. This is why the shaft has even more forward bend than is normally expected.

Basically , if you are a swinger the club is pulling your hands through impact

6. Other important points to note are:
a. There is not enough time to do anything via your hands (at the grip end) to affect the clubheads motion close to and through impact . Any forces/torque impulses you apply to the grip will take too long for its effect to reach the clubhead for the 0.0004 secs impact period. Therefore the shaft can be assumed to be like a piece of string while the clubhead can be assumed a free moving object through space (ie. when its approaching impact ). I did ask Dave Tutelman where exactly in the downswing path can the shaft be assumed to be acting like a length of string but he didn't have a ready answer.
b. For a driver being swung at 100mph , the dynamic weight of the club at P6 (shaft horizontal in downswing ) will feel like 3 stone weight force, while just before impact it will feel like 7 stone. That is equivalent to swinging a bag of cement , so I can't imagine one being able to increase clubhead speed just using muscular wrist torques.
c. Now this is a really counterintuitive part , but any bend of the shaft 'DOES NOT ROTATE' with the shaft . So even if the golfer rotates the shaft with his arms/forearms , the shaft bend will not rotate with the shaft.

Also , note that Ben Hogan did not laterally slide . In the backswing his right hip moved back and towards the target , it then stabilised in space and he re-rotated his pelvis around the right hip. To someone looking from a face-on view it looks like he has slid his hips targetwards but that is not the case.

The reason why the arms decelerate while the club accelerates is because of Newtons 3rd Law but it applies to 'Torques' too .

"If object A exerts a torque on object B about a given axis, then B exerts an equal but opposite torque on A about the same axis"

So while the arms generate a torque on the club (using eccentric forces through the wrist joints) , the club will apply an equal and opposite torque on the arm (via the wrist joints), therefore the club speeds up while the arms decelerate .

Not sure how all this will help any golfer improve their swings but it might help them identify flawed golf instruction and save their hard earned cash.
WILDTHING, Thanks for your conscientious effort to discuss the various points about the golf swing. I wish to reply to some of those points to explain the understanding of the matter discussed rather than dispute what is written per se.
1. I agree all pro golfers have forward shaft bend. But all of the shafts have 'concave' shape. That is due to the method of the modern swing. What I am proposing is a 'convex' bend going forward through impact. We need to appreciate that driving distances have stagnated over the last two decades. In 2018, Rory McIlroy, the distance leader, outdrove John Daly's effort in 1999 by a mere 14 yards. That is meager given the advance in ball and equipment technology. Thus, I am proposing a 'convex' bend to strike the ball because the convex bend is significantly more powerful than the current 'concave' bend displayed by all pro golfers' swings.
2. The clubhead speed depends on the total force generated by the rotational movement of the lower body driving the upper body and then through the left arm dragging the club through the ball.
3. I subscribe to Mindy Blake's idea of the body and left arm dragging the club through the ball.
4. It is the centripetal force that determines the speed on the clubhead which transfers the power on the ball. It is the centrifugal force that propels the ball on its way (I think).
5. I subscribe to Blake's concept of dragging the club through the ball. If anything can be related to 'release', it
the ball staying on the clubface a little longer, much like the ball being stretched on the strings of a tennis racket in the stroke.
6. a. I agree there is not enough time for the hands to do anything with the ball.
b. I agree.
c. I agree. The shaft can only change its shape by unbending and not rotating.

No, I did not suggest that Hogan made a lateral slide in the backswing. I only said that Hogan devised a lateral slide and turn to initiate the downswing to suit the wide shoulder-width stance. That may be a misread on your part.

I understand Newton's law - for every action, there is an equal and opposite reaction. But my reasons for the arm and club decelerating throughout the impact zone are due to two factors (1) Hogan's slide and turn movement in the downswing is an inefficient motion (2) the left foot at 22 degrees is insufficiently open and impedes the downswing. I plan to do a separate post on the downswing later.

Having made the above clarifications, I plan to expand on the various points that are summarised in the brief genesis as provided in my initial post on a 'probable' convex strike on the ball. I shall take the participants of this forum through till the end. It probably takes several posts.

By the end of my postings, I should make the case for the striking the ball with a 'convex-bend' shaft. The 'convex-bend' shaft will outperform the 'concave-bend' shaft that is prevalent in all pro golfers' swings.

I do hope my readers will be patient and persevere with me. Meanwhile, thank you all for viewing my postings. My next post should be early next week.
 

WILDTHING

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Hi CSF

1. I'll be interested in how you will propose a golfer create 'lagging' bend into impact (when most Tour pros cannot). Tom Wishon doesn't think so :)

(Note :Although I suspect they might be able to do this for short irons)

2. There might be some energy being passively transferred from the lower body to the upper body to increase clubhead speed but its a lot more complicated. For example , LPGA players have on average faster pelvis/thorax rotation than PGA players but they don't drive the ball further. Also , you must have seen some golf instructors sitting in chairs (without any lower body involvement such as pelvis rotation or use of ground reaction forces) and just swinging their arms to create clubhead speeds which can be 70-80% of their 'normal swing' clubhead speeds.

3. Mindy Blake has concepts/theories (like a plethora of other golf instructors and biomechanic experts) but there is still not enough evidence to 100% confirm they are correct or not , especially 'cause and effect'. I have a book called the 'The Secret Of Golf' by George Peper packed full with a variety of theories. Note that the scientific research evidence shows that the hands exert a negative torque on the grip as the club approaches impact although you might feel as if your dragging the club through (especially if your hands are forward of the ball at impact - but feel is not real).

4. Centripetal force 'sustains' rotation while 'torque' creates it . Again , you might feel as if the clubhead is pulling your arms outward but there is no outward force on the 'clubhead' . Your arms are pulling on your hands, that are pulling on the grip and shaft creating tension in the shaft that is pulling on the COM of the club. Because of Newtons 3rd Law , the shaft is also pulling on your hands and arms and this is can be termed the 'Centrifugal force' . But there is no outward force acting on the COM of the club.

5. The period of impact between the club and ball is 0.0004 secs . Check out this site by Tutelman but it can get very complex if you are not into maths/physics/shaft technology.


I don't know whether Ben Hogan slide and turn movement in the downswing is an inefficient motion - what defines an inefficient movement and how is that measured?

Why should the left foot flared at 22 degrees impede the downswing if you already have great pelvic/torso flexibility ? For those with poor pelvic/torso separability they might find that excessive flaring of the left foot will impede their backswing (as would not flaring the right foot). The golfer will have to find the 'best fit' dependent on their capabilities and limitations.

Good luck with the postings and it will be interesting to read your theories although I'm wondering whether they will be similar to those put forward by Ben Allen Junior (who also thinks that increasing the centripetal force by reduction of swing radius will also increase clubhead speed -see link below).

 
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Misike

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There is no doubt that JB Holmes, if he is the golfer you are referring to, can do the convex strike on the ball. But he needs to adopt a new system that I am devising.

It is not about the shaft characteristics but the system that will change the swing dynamics.
This one made me smile :). The JB he is referring to is far from JB Holmes. One plays fast, one not so much.
 

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