Using the ground as leverage

[shootin4par]

mandrin,
I made this statement in the other thread and would be interested in your thoughts on the post

"The golf swing is all about energy, creating energy and releasing energy. a Law of motion, objects in motion stay in motion
In the golf swing on the downswing your left shoulder goes three ways, forward UP and in, but once the left shoulder gets to a certain point it is back up and in. The keyword there is UP. you transfer energy down to the ground and what happens? it either stays there if the structure collapses or he posts his left side and it shoots back up. Thats the only two possibilities. When a baseball pitcher crouches down onto the rubber his weight/energy is going down and back, so on his forward motion he and the energy go up and forward off of the rubber."

 

[Mr Inconsistent]

People would have a better shot of consciously pulling off the move if they thought of straightening the left leg (and entire left side of the body too might be helpful) more quickly throught impact than if they tried to just jump.

 

[shootin4par]

but if it is conscious instead of a reaction, mistiming the move can become an issue

 

[puttmad]

...

I can’t think of any teacher teaching these moves as such. But Bob Mann comes to mind, coming close, teaching a vertical sit down as the only conscious move in the down swing. .

Bobby Shaeffer talks about it a lot on his DVDs...didn't help me much tho...

 

[puttmad]

....

To get UP through impact, you need to get DOWN during the initial stages of the downswing, no? Many pros talk about the "squat" move at the start of the downswing. Sam Snead is an example of this, I suppose. He certainly seems to get the left heel down during the initial phase of the downswing.

Just watched my Brad Petersen DVD again...he doesn't squat during the swing as such. He addresses the ball with very low hands, so basically he does the squat before he even moves the club.
Before impact both his heels are off the deck at least 3 inches, so no "left heel down" move there. then.

 

[Jono]

Puttmad,

Is there anywhere on the internet where I can see this Brad Petersen's swing?

My opinion is that this "up move" through impact happens pretty naturally. The extra few mph it can give you is offset by decrease in accuracy and consistency. Like bbftx, I've worked on decreasing this up move and staying on my feet more through impact.

 

[puttmad]

...

Puttmad,

Is there anywhere on the internet where I can see this Brad Petersen's swing?

My opinion is that this "up move" through impact happens pretty naturally. The extra few mph it can give you is offset by decrease in accuracy and consistency. Like bbftx, I've worked on decreasing this up move and staying on my feet more through impact.

I have PM'd you

 

[mandrin]

mandrin,
I made this statement in the other thread and would be interested in your thoughts on the post

"The golf swing is all about energy, creating energy and releasing energy. a Law of motion, objects in motion stay in motion
In the golf swing on the downswing your left shoulder goes three ways, forward UP and in, but once the left shoulder gets to a certain point it is back up and in. The keyword there is UP. you transfer energy down to the ground and what happens? it either stays there if the structure collapses or he posts his left side and it shoots back up. Thats the only two possibilities. When a baseball pitcher crouches down onto the rubber his weight/energy is going down and back, so on his forward motion he and the energy go up and forward off of the rubber."

shootin4par,

It is true that a golf swing is about first creating kinetic energy and subsequently the timely release of this energy, hence two distinct phases. Have a look at an archived post touching on these matters. The young male golfer trying to impress his girl friend is often generating impressive amount of kinetic energy but does not release it timely and obtaining often dismal results.

There are many ways to swing but one is to swing from the inside, up and out, and letting cf do its work. It involves allowing hips, shoulders and arms to slow down naturally in the down swing to maximize kinetic energy transfer to the most distal part - the clubhead. This is the most energy efficient way to swing. The easy looking swing yet producing surprising clubhead velocity is likely in that category.

I don’t think that hitting into a solid left side is an absolute requirement for such efficient energy transfer. Sort of sitting into and sliding into the left side, keeping the bent in the lead knee will do also. An essential ingredient is that the bigger masses slow down, it does not matter how exactly. I don’t think energy in a downswing to be moving down and then up; it flows essentially from the inside to the outside, from the inner core to the clubhead.

 

[Mr Inconsistent]

To crack a whip you have to pull the whip the other way, same thing with hitting a golf ball. Straightening up the left side which in many cases results in an on the toe or jump move is what happens when the the golf version of pulling the whip the other way happens through impact.

 

[Mr Inconsistent]

puttmad, the heel down move is still valid but that is just a move for the begining of the downswing. By impact it's not applicable.

Watch Couples put his left heel down and then lift it back up again through impact.
http://youtube.com/watch?v=5BomOzjHp-w

 

[shootin4par]

thanks mandrin
you say the large parts stop so the rest can catch up and that produces energy. In watching Mike austin swing I noticed that, Is that what you are talking about?

 

[mandrin]

thanks mandrin,
you say the large parts stop so the rest can catch up and that produces energy. In watching Mike austin swing I noticed that, Is that what you are talking about?

shoot4par

Not really stopping, but decelerating, slowing down before impact, transferring some energy to the more distal parts. For instance, typically arms slow down prior to impact. It happens quickly and usually goes unnoticed.

Think of a whip. It has progressively a smaller diameter towards the distal end. This is essential for the huge speed multiplication obtained. The kinetic energy is flowing trough less and less mass, hence the velocity has to increase as the kinetic energy is mostly conserved.

Very crudely the human body can be thought of as a whip. The bigger parts, when slowing down transfer kinetic energy to the smaller parts increasing their velocity. The same basic process at work as for a whip. From body, to arms, to club, there is each time a much smaller mass, essentially to obtain speed multiplication when kinetic energy is transferred.

Brian somewhere has clearly indicated that his observations are along these lines. There can be around impact sort of a quick stutter in the swing when this transfer takes place and than the process reverses and kinetic energy is flowing back into the body back form the high velocity clubhead. The very old advice to hit against a solid led side has its justification in the more efficient energy transfer it allows from body to arms/club.

The very short sharp vertical sit down move, “sitz”, as taught by old timer Joe Norwood, is another example of deceleration and subsequent quick transfer of energy to arms and club right from the very start of the downswing. I don’t quite believe that the perfect circular swing is the most efficient way to swing to produce maximum clubhead velocity even if some believe this to be the case. You will see frequently instruction for some type of vertical move from the top usually referring to hands/arms or trail shoulder.

 

[golfbulldog]

Do you think that the effort to move the pivot ( ie. what the player actually tries to do) remains the same throughout the downswing but that the pivot is slowed by the arms and club moving away from the body?

Is this correct physics?

Ie. The player never perceives the pivot stopping because their muscular effort is approximately constant? Just that the amount of work the pivot has to do is increased around release point ... so either the pivot slows or the work increases?

Looking forward to being corrected on my physics by Mandrin!

 

[mandrin]

Do you think that the effort to move the pivot ( ie. what the player actually tries to do) remains the same throughout the downswing but that the pivot is slowed by the arms and club moving away from the body?

Is this correct physics?

Ie. The player never perceives the pivot stopping because their muscular effort is approximately constant? Just that the amount of work the pivot has to do is increased around release point ... so either the pivot slows or the work increases?

Looking forward to being corrected on my physics by Mandrin!

golfbulldog, let me expand a bit on your correct intuitive physics.

From the top, arms and club are close to the axis of rotation minimizing angular inertia. For a given torque this allows to quickly obtain a larger angular velocity. Very soon there are large inertial forces coming into play of which centrifugal force is the dominant component. This force strives to get every bit of mass as far as possibly away from the axis of rotation, and it translates into inertial torques operating at the various joints.

For instance, it exerts a torque on the club, but also an equal but opposite torque on the arms. Hence the club accelerates and the arms decelerate. Since the arms are much heavier than the club there is a large effect on the club and a small effect on the arms. The slowing down of the arms became only common knowledge with the advent of high speed photographic means.

We have muscles around the joints which can also exert torques in addition tot the inertial torques. So we have the choice to let cf to its job or throw in also our muscular torques into the swing. The nice thing about cf is that it automatically furnishes the correct timing for release of the club. This is a bit of a paradox, less we interfere with the swing more it is like that of a machine.

 

[golfbulldog]

golfbulldog, let me expand a bit on your correct intuitive physics.

From the top, arms and club are close to the axis of rotation minimizing angular inertia. For a given torque this allows to quickly obtain a larger angular velocity. Very soon there are large inertial forces coming into play of which centrifugal force is the dominant component. This force strives to get every bit of mass as far as possibly away from the axis of rotation, and it translates into inertial torques operating at the various joints.

For instance, it exerts a torque on the club, but also an equal but opposite torque on the arms. Hence the club accelerates and the arms decelerate. Since the arms are much heavier than the club there is a large effect on the club and a small effect on the arms. The slowing down of the arms became only common knowledge with the advent of high speed photographic means.

We have muscles around the joints which can also exert torques in addition tot the inertial torques. So we have the choice to let cf to its job or throw in also our muscular torques into the swing. The nice thing about cf is that it automatically furnishes the correct timing for release of the club. This is a bit of a paradox, less we interfere with the swing more it is like that of a machine.

Thanks for definitive answer. Good to see you posting again. ( perhaps topic for your future physics knowledge would be on "matching" clubs - eg. swingweight/ Moment of inertia etc.... )

Thanks

 

[tobell]

Thanks Mandrin

Madrin,

Always very exciting to see you post. Thanks for sharing your knowledge, hardwork and time. Your posts are simply fantastic!

 

[mandrin]

Mandrin,
Always very exciting to see you post. Thanks for sharing your knowledge, hardwork and time. Your posts are simply fantastic!

tobell,
it is refreshing to read your post since many expect to find almost everything for free on the web. Indeed there is much time and effort involved. Thanks, I appreciate.

 

[golfbulldog]

what if...

If a player increased their pivot work during the period when the pivot usually slows down....

I suspect that this is difficult to do and the pivot would just slow down less... but what would happen to the clubhead speed and location?

Would it still achieve inline position at the same place ( as if pivot work were constant)? Would the clubhead speed increase??

I see this a bit like a ride-on lawn mower with a belt driven cutter. When the cutting blades are not engaged it moves quite quickly at any given RPM of the driving motor... switch a lever and belt engages... amount of work demand increases and the mower travels more slowly for the same RPm of engine? At least that is what seems to happen. Maybe some complicated stuf about the TORQUE of an engine versus the TORQUE of a pivot... maybe can not resist impact deceleration through the clubshaft ... maybe resist pivot deceleration through a pivot with high torque... ( i like the sound of this idea but am scared that i just got into the physics deep end of the pool and forgot my lifejacket... just waiting for the sharks! )

WIth engine you can increase power and cut and travel at same speed as original ...

Can you increase the power of you pivot and stop it slowing ? ... would this be beneficial?

Thanks anybody who helps.

Special thanks to Mandrin - inspiring non-physics people to at least dabble in physics thoughts!

 

[puttmad]

...

If a player increased their pivot work during the period when the pivot usually slows down....

I suspect that this is difficult to do and the pivot would just slow down less... but what would happen to the clubhead speed and location?

Would it still achieve inline position at the same place ( as if pivot work were constant)? Would the clubhead speed increase??

I see this a bit like a ride-on lawn mower with a belt driven cutter. When the cutting blades are not engaged it moves quite quickly at any given RPM of the driving motor... switch a lever and belt engages... amount of work demand increases and the mower travels more slowly for the same RPm of engine? At least that is what seems to happen. Maybe some complicated stuf about the TORQUE of an engine versus the TORQUE of a pivot... maybe can not resist impact deceleration through the clubshaft ... maybe resist pivot deceleration through a pivot with high torque... ( i like the sound of this idea but am scared that i just got into the physics deep end of the pool and forgot my lifejacket... just waiting for the sharks! )

WIth engine you can increase power and cut and travel at same speed as original ...

Can you increase the power of you pivot and stop it slowing ? ... would this be beneficial?

Thanks anybody who helps.

Special thanks to Mandrin - inspiring non-physics people to at least dabble in physics thoughts!

GBD

In layman's terms logically only one thing would need to happen if you increase the speed of the pivot to try and stop it slowing.
Correspondingly you would need to speed up the straightening process of the right arm on the downswing, to square the blade for impact at the earlier time.

But there is a better way... Simply reverse the process.

Instead of pivoting faster and then trying to figure what to do with the rest of your body, simply let the pivot follow or keep up with what the rest of your body is doing...
Confused? you should be

The key is to get the club moving faster and THEN speed up the pivot to match the clubhead and keep everything in balance, albeit faster......

This way around is far easier to achieve...

 

[golfbulldog]

GBD



The key is to get the club moving faster and THEN speed up the pivot to match the clubhead and keep everything in balance, albeit faster......

This way around is far easier to achieve...

But doesn't "The inside move the outside"... its just that the outside then starts to slow the inside when the centre of gravity of the arms / clubhead ( the outside) is further away from the rotational centre.

I am not suggesting increasing the speed of the pivot, merely minimising its deceleration. In my laymans terms that involves the pivot doing more work.

It seems that many pivots get lazy and have no torque. As soon as there is higher workload placed on the pivot ( due to mass moving in rotation at a greater distance from the centre) then they slow too quickly and even stall. this makes it almost impossible to trace a straight plane line and pivot stalling leads to flipping and bent plane lines... maybe

Still treading water in the deep end...

I just don't like the idea of pivot keeping up with the clubhead... what does Ben Doyle talk about "not pushing shopping carts faster than you can run " ( or something like that)... you're saying that you should get the cart going as fast as it can and then run to keep up....

I'm not sure... still like the idea of a high torque pivot - that is what drives the swinging motion.