The marvel of pronation! And suppination?

[LeeD]

I AM odd.
I don't care for convention.
I chose my own path, regardless whether I should have or not.
I'm proud of my chosen path (right now, this second, might change next second).
I think StefanEdberg can figure out if his rackeface is open or closed. He MIGHT NOT figure out whether he's watching the ball closely enough, whether his stance stays more open than normal, or whether his shoulders turned as much as his good forehands.
He uses that forehand because his grip change is soooo slight he can volley and half volley with it.
He can still hit 7.0 forehands when he's on.

 

[OrangeOne]

He uses that forehand because his grip change is soooo slight he can volley and half volley with it.
He can still hit 7.0 forehands when he's on.

I once owned a Stefan Edberg shirt, which I liked less than my Ivan Lendl Shirt.
Ivan Lendl sometimes hit behind the back when on the run.

^^I figured from your post we'd changed the game to raising points that while factual are not in any way being debated?

 

[LeeD]

Antidotes are always fun, and can make or break your day..

 

[OrangeOne]

Antidotes are always fun, and can make or break your day..

So can anecdotes.

Antidotes can, on the other hand, save your life. Which would likely make or break your day.

 

[LeeD]

Lesson learned, not bad for a rainy day.

 

[Counter]

Incorrect.

Pronation and supination are rotations of the forearm (and foot) as I stated previously. Those palm orientations (palm movements) are normal results of rotations of the forearm and/or the shoulder.
Take a look at the FH g'stroke. The forearm often goes thru a sequence of pronation and supination (and perhaps some shoulder rotations) just on the takeback alone for elite players. If the racket face is appreciably closed at the start of the forward swing but nearly square at contact, the forearm supinates to accomplish this. The pronation that you see on the follow-thru actually starts just before contact with the ball (and is not just an unrelated artifact of the follow-thru).
.

Yes. This (the bolded parts) is what I've always suspected, but never seen explicitly stated in what I've read about pronation and supination.

Thus basically, if the angle (orientation) between the racket face and the horizontal court plane has changed between a moment M1 and a later moment M2 during the forehand stroke (including takeback), then that change in angle should be a fair measure of the net amount of pronation (if the racket is more closed at M2 than it was at M1) or supination (if the racket is more open at M2) that has been going on between M1 and M2.

This could be otherwise only to the extent that other body parts (than forearm and perhaps wrist) are responsible for the change in angle. And it does seem like a sound assumption that it is indeed mainly (though no doubt not exclusively) the forearm rotation that is responsible for such change in angle.

(Although, to be sure, SystemicAnomaly mentions "the forearm and/or the shoulder", so presumably the shoulder contributes as well. This could perhaps be subsumed under a slightly wider notion of pronation/supination that includes rotation, not only of the forearm (and possibly the wrist), but also of the upper arm up to the shoulders.)

 

[SystemicAnomaly]

I understand that pronation of the forearm may occur at the end of a forehand.

However, if you were trying to teach someone to hit a ball, would you be mentioning pronation at all? Going out and thinking of how much I have pronated on my forehand is not something that is going to make me a better tennis player.

This thread should simply be renamed the marvels of the follow through.

I misunderstood the message of your previous post. Yes, you are correct, we do not need to mention anything about pronation of supination to teach the strokes. But no, pronation is not just something that happens at the end of a forehand.

Yeah, but here's the thing: you don't teach tennis by talking about the rotation of the forearm. You don't teach topspin by saying "pronate a little more as you contact, and then more after contact". You just don't. Pronation happens as a result of the outcomes you're requesting.

You use language like "close the racquet face", "add some roll over the ball".

Put another way, I have a student who stands too close to the ball, which results in all sorts of bad things happening. So I tell him to "not get as close to the ball", to "extend his arm and then give himself room", etc.

I could just as easily say "add some shoulder abduction", "use you abductors to move your racquet away from the body"... but would I? This thread seems to say that I would. Odd...

Duh! We are not necessarily discussing how to teach in this thread. I view this as a thread on some of the mechanics of the stokes, not teaching techniques. The OP gained some insight when he discovered the true nature of pronation. He also asked if supination desireable. That was the focus of the thread.

 

[Mr_Shiver]

Shouldn't we be emphasizing the kinetic chain rather than isolated segments? Isn't the forearm simply a link in the kinetic chain? I am a macro view person and all these details have me at sea.

 

[toly]

You might try digging into the books and scholarly articles by some of the PhD's in the field of tennis biomechanics. This would include people like E. Paul Roetert, Duane Knudson, Todd S. Ellenbecker, Jack L. Groppel and others. (Don't know if Groppel has done much research or writing in the field in the past decade or so tho'). Perhaps you could use the following as a starting point:

cross-fitllc.com/wp-content/uploads/2010/06/Biomechanics-of-the-Tennis-Groundstrokes.pdf


http://www.itftennis.com/coaching/publications/powerpoints/english/biomechanics.asp
.

Thank you very much, for interesting links.

 

[toly]

Nadal’s forehand

... plus the contribution from the biceps pulling the racquet up and across and causing the elbow to bend. It is simply because these movements are controlled by muscles that are much more powerful than the muscles involved in pure forearm rotation. Just try performing the movements in isolation to get a sense of what I am saying.

Figure 1. Nadal’s forehand
Around impact, Nadal constantly keeps his arm straight. He starts using the elbow flexion much longer after impact, see Fig.1.8. It means the topspin is mostly defined by the forearm pronation, shoulder internal rotation and vertical component of the arm velocity (not by the elbow flexion). Nadal’s forehand routine is very simple for teaching, understanding and execution. Btw, with this technique, no matter what kind of grip Nadal employs (eastern, western est.); the topspin angular speed will be the same. All publications, the western grip can produce more topspin just do not correspond to reality (see Fig.1).

 

[OrangeOne]

Nadal’s forehand routine is very simple for teaching

I stopped reading right there.

Anyone who says such a thing has never coached tennis, and thus shouldn't say what is or isn't simple to teach.

 

[Manus Domini]

Figure 1. Nadal’s forehand
Around impact, Nadal constantly keeps his arm straight. He starts using the elbow flexion much longer after impact, see Fig.1.8. It means the topspin is mostly defined by the forearm pronation, shoulder internal rotation and vertical component of the arm velocity (not by the elbow flexion). Nadal’s forehand routine is very simple for teaching, understanding and execution. Btw, with this technique, no matter what kind of grip Nadal employs (eastern, western est.); the topspin angular speed will be the same. All publications, the western grip can produce more topspin just do not correspond to reality (see Fig.1).

why is there a picture of nadal? I wouldn't even try copying his forehand, for a few reasons; the least of these is that it would not at all help my specific game style, only hinder it...

and why is there false information? a western grip will always produce more topspin, he will produce topspin with this stroke, but the more western the grip, the more topspin. that being said, Nadal does not use a western grip

 

[toly]

why is there a picture of nadal? I wouldn't even try copying his forehand, for a few reasons; the least of these is that it would not at all help my specific game style, only hinder it...

and why is there false information? a western grip will always produce more topspin, he will produce topspin with this stroke, but the more western the grip, the more topspin. that being said, Nadal does not use a western grip

Nadal is #1. TIW, we must learn something about his forehand routine. Btw, he has very good company: Federer, Verdasco, Gonzales etc are using similar forehands. Nadal technique is very simple, at least for me, and very natural. See my post
http://tt.tennis-warehouse.com/showthread.php?p=5241650#post5241650
Federer, with similar forehand, but eastern grip still is able to generate topspin. If Nadal used the same eastern grip; he, no doubt, would generate topspin as well. The pronation, internal shoulder rotation, and arm rotation in tilted plane are responsible for topspin, not grip by itself. These motions practically are not defined by grip’s type.

 

[Mr_Shiver]

You should post a video of your Nadal fh.

 

[toly]

You should post a video of your Nadal fh.

Unfortunately, I cannot do it.

 

[LeeD]

If I could hit Nadal's forehand, I'd be 40 years younger, in much better shape than I ever could be in, have superior eyes and coordination, be a better athlete, be taller and much stronger, have tons more training, and expend much more energy than I had when I was 21.
That's all, easy, right?

 

[OrangeOne]

You should post a video of your Nadal fh.

Unfortunately, I cannot do it.

One suspects the inability is with regard to the forehand more than the recording thereof.

If I could hit Nadal's forehand, I'd be 40 years younger, in much better shape than I ever could be in, have superior eyes and coordination, be a better athlete, be taller and much stronger, have tons more training, and expend much more energy than I had when I was 21.
That's all, easy, right?

Precisely. You'd also be willing to wear out your body in a 10-year period, in exchange for tens of millions of dollars.

 

[bhupaes]

Around impact, Nadal constantly keeps his arm straight. He starts using the elbow flexion much longer after impact, see Fig.1.8. It means the topspin is mostly defined by the forearm pronation, shoulder internal rotation and vertical component of the arm velocity (not by the elbow flexion). Nadal’s forehand routine is very simple for teaching, understanding and execution. Btw, with this technique, no matter what kind of grip Nadal employs (eastern, western est.); the topspin angular speed will be the same. All publications, the western grip can produce more topspin just do not correspond to reality (see Fig.1)

Hi toly, nadal's biceps are working really hard pulling the racquet up through the stroke, although it is hard to see from the pictures. You are right, the elbow breaks later, but I believe the acceleration due to the biceps has started well before the hit, and this is how it is for most players - the elbow breaks later, with stylistic differences. It seems to me that his whole arm is moving up and across, and this is the biggest component of the stroke - more so than pronation, IMO, but others are allowed to think differently. Also, the initial part of the pronation seems to be due to upper arm rotation, and the forearm part (radius crossing ulna) seems to happen later as a natural part of the finish. In all, I would say that the fundamentals of the Nadal forehand are not unique, but he does it in his very unique style, with a straight arm.

If someone were to emphasize pronation as his main power source, he would end up hurting his arm badly if he were trying to generate the same kind of power and spin as Nadal - IMHO.

 

[OrangeOne]

If someone were to emphasize pronation as his main power source, he would end up hurting his arm badly if he were trying to generate the same kind of power and spin as Nadal - IMHO.

The bicep is... at a guess... 3 to 6 times the size of the muscles used for pronation. Ditto for the shoulder muscles.

Spin & the forehand in general is produced a LOT more from the shoulder and the upper arm and the body than it is from the rotation of the forearm.

Put another way - explore the comparative strength of different elements:

• Coil / trunk: Try hitting a ball with a stiff arm, just coiling and uncoiling your body - you'll go ok. Baseline to over the net likely.
• Bicep: Try hitting a ball just by flexing your arm with your bicep. Still ok, probably to or over the net.
• Shoulder: Try hitting a ball with just a swinging straight arm, you'll go pretty damn well. Length of the court for some?
• Pronators: Try hitting a ball by just pronating (rotating) your forearm. You'll be lucky to go a few yards.

 

[bhupaes]

^^^ Agreed. After a long period of dabbling with dubious/wrong ideas, I now absolutely believe that the big muscles do the heavy lifting (literally!) and the smaller stabilizers help with guidance and positioning. That is not to say we ignore the smaller muscles - quite to the contrary, they need to be in really good shape for developing quality strokes and also surviving the battering from the big muscles. I believe it's important to use cues that make us focus on the big muscles in order to develop good strokes.

 

[Mr_Shiver]

I think threads like this are helpful, but only as long we don't lose sight of the big picture of a stroke. To maximize the potential of any stroke you really want to get the whole body involved. You don't want to over emphasize one aspect to the detriment of others. The only thing I would over emphasize is footwork. Coming back from a high ankle sprain with sloppy footwork has been a real eye opener. I have been getting trounced by guys I usually own.

 

[bhupaes]

^^^ Well, I would go further and say that threads like this are useful only in getting some intellectual insight into what's going on in these strokes. For purely self-coached guys like me with limited time, it provides some guidance for practicing the right way. There's nothing like having a good coach provide cues that take the "thinking" out of playing, and having the time to practice for hours every day!

 

[toly]

Biceps Functions

Hi toly, nadal's biceps are working really hard pulling the racquet up through the stroke, ...

Hi bhupaes,
The most important of the biceps functions is to supinate the forearm and flex elbow. Nadal doesn’t use these motions (around impact) at all. See please http://en.wikipedia.org/wiki/Biceps_brachii_muscle

 

[toly]

If someone were to emphasize pronation as his main power source, he would end up hurting his arm badly if he were trying to generate the same kind of power and spin as Nadal - IMHO.

Definition: The flat component is part of the racquet speed (around impact spot), which direction is perpendicular to the racquet spring bed.
I stated in post # 38 that pronation generates topspin component of the racquet speed. The topspin component is mostly responsible for ball rotation, not for the ball linear speed. The flat component provides the ball linear speed. The flat component of the racquet velosity is mostly created by the arm rotation in the tilted plane by using shoulder joint and is also created by wrist ulnar deviation.
Arm rotation in the tilted plane also creates vertical (topspin) component of the racquet speed. If this plane is horizontal and racquet string bed is vertical, the arm rotation produces just flat component (no topspin). In this occasion, only pronation and internal shoulder rotation can produce topspin.

 

[OrangeOne]

Hi bhupaes,
The most important of the biceps functions is to supinate the forearm and flex elbow. Nadal doesn’t use these motions (around impact) at all. See please http://en.wikipedia.org/wiki/Biceps_brachii_muscle

Nadal also doesn't pronate much around impact either, most of it happens after impact.

Also, to assume that that biceps only do those things is fallacious, and is the sort of musculoskeletal knowledge that one might acquire from Wiki. How about the biceps being responsible for the constant positioning of the elbow under load - an isometric contraction. There's a HELL of a lot of isometric contraction going on to keep an arm straight under load - we'd break our elbows without such contractions.

Finally, I love how the forehand you've 'analysed' - to me - looks like a warmup ball, and is about as basic as the Nadal forehand gets.

I stated in post # 38 that pronation generates topspin component of the racquet speed. The topspin component is mostly responsible for ball rotation, not for the ball linear speed.

Ever tried to hit topspin consistently without having the racquet start below the ball? Can be done, but it's brutal on the arm. Most of the topspin comes from the path of the racquet. A little pronation helps to varying degrees, but to be honest, for most, much of the pronation is (as pointed out by MANY) happening after contact, just like you say the bicep flexion is!

If most normal humans are creating most of your topspin from pronation, they're going to wear out pretty quickly and risk injury as well.

 

[SystemicAnomaly]

Hi bhupaes,
The most important of the biceps functions is to supinate the forearm and flex elbow. Nadal doesn’t use these motions (around impact) at all. See please http://en.wikipedia.org/wiki/Biceps_brachii_muscle

A side bar here (since it really is not germane to the discussion at hand). The biceps are involved in supination primarily when the elbow is bent. When the arm is straight (no elbow bend), the biceps provide little or no assistance to the forearm for supination.

 

[toly]

A side bar here (since it really is not germane to the discussion at hand). The biceps are involved in supination primarily when the elbow is bent. When the arm is straight (no elbow bend), the biceps provide little or no assistance to the forearm for supination.

Yes, I agree absolutely. You demonstrate very deep knowledge about this stuff. Do you have any medical background?

 

[toly]

If I could hit Nadal's forehand, I'd be 40 years younger, in much better shape than I ever could be in, have superior eyes and coordination, be a better athlete, be taller and much stronger, have tons more training, and expend much more energy than I had when I was 21.
That's all, easy, right?

Yes, you can! Yes, we can! Yes, I can! Just be more optimistic. Nothing is impossible!!!

 

[bhupaes]

Toly, OrangeOne has already said exactly what I had in mind regarding the function of the biceps. Keep in mind that in the end, the racquet touches the ball for a few milliseconds, during which an upward force causes the ball to topspin. You can isolate the muscles and see which one creates the maximum acceleration/speed/force leading to the point of contact. It's definitely the bigger muscles, no question about it. You are right in that a lot of the movement caused by the big muscles is linear. The most important effect of pronation, starting just before contact, is to redirect a lot of this enormous force upwards. This is the real reason, IMO, for the abrupt change of direction you see very close to the point of contact in the strokes of great players like Federer, Nadal, Davydenko, and others. Thus, pronation provides a positioning/redirecting effect, and not one that supplies the brute force, in top level tennis. I am not saying pronation contributes no force - only that it is not the main contributor.

Because it is such a complex movement, I believe it is very difficult to explain what's going on, and I'm sure I'm barely scratching at the surface. I kinda pieced it together in one of the earlier discussions with 5263 regarding Davydenko.

 

[toly]

Nadal also doesn't pronate much around impact either, most of it happens after impact.

What is the reason to pronate after impact?

 

[LeeD]

Nadal's long fast swing, coupled with his grip (strong side of SW) allows a natural pronation after impact. If he adopted an eastern or conti grip, he would HAVE to force the pronation.
My SW grip is similar, I hit 1/2 as hard as Nadal, and my followthru naturally rolls over so the hitting face is facing my opponent, but from the RIGHT side of my body...me lefty. Just a function of the GRIP USED. You have to fight NOT to pronate with strong grips.
And we all know from golf, a strong full followthru insures a replicable stroke.

 

[toly]

Nadal's long fast swing, coupled with his grip (strong side of SW) allows a natural pronation after impact. If he adopted an eastern or conti grip, he would HAVE to force the pronation.
My SW grip is similar, I hit 1/2 as hard as Nadal, and my followthru naturally rolls over so the hitting face is facing my opponent, but from the RIGHT side of my body...me lefty. Just a function of the GRIP USED. You have to fight NOT to pronate with strong grips.
And we all know from golf, a strong full followthru insures a replicable stroke.

Does natural mean involuntary? How can the grip force us to pronate or not pronate? And again I repeat my question. What is the reason to pronate after impact?

 

[LeeD]

Ever play golf? You cannot hit a repeatable long stroke without turning over your two wrists at the correct time. The correct time appears to be governed by the pose of your final, static position after followthru. EVERY top golfer followthrus the same.
As in tennis?
Do you play tennis? If yes, try adopting a very strong SW or W grip, and try hitting hard fast shots and NOT pronate! You can do it, but at the expense of your shoulder muscles or tendons.
So follow your long fast strokes with it's given followthru, don't fight the flow.

 

[OrangeOne]

Hi bhupaes,
The most important of the biceps functions is to supinate the forearm and flex elbow. Nadal doesn’t use these motions (around impact) at all. See please http://en.wikipedia.org/wiki/Biceps_brachii_muscle

What is the reason to pronate after impact?

Cute question, but my comments were somewhat paraphrased, directed at yours that I've re-quoted. You were dismissing the activity of the bicep as 'not happening around impact', I was making a similar comment about pronation....

 

[Manus Domini]

so in other words, don't rely too heavily on pronation on the forehand?

 

[dozu]

in a normal, well timed FH, pronation should happen naturally. It's just how the human forearm is build, when the shoulder internal rotation happens, the forearm pronation happens, without you trying it..

now.... when hitting live balls, situations vary.. different part of the kinetic chain (legs, hips, core, shoulder, arm, hand) may contribute more or less to generate racket head speed. It's like a multi-stage rocket.

if for some reason, the early stage rocket could not contribute enough - you are running really wide, or bad bounce causes ball to skid forward, or ball catches gust and goes too far away from you etc etc..... then the later stage rocket has to work harder, which means forearm aggressively does the pronation to speed up the racket head.

So I'd say pronation is reactionary. You don't pay attention to it when timing is perfect.... but you can use it intentionally when you are in a pinch.

http://www.youtube.com/watch?v=ktIo0PHa0e4&feature=related

In this video, Fran hit a bunch of well timed FH, where her forearm was working mostly in a reactionary manner, until at 00:24, she has to do a half-volley type pick up, and you can clearly see that on that shot she was less aggressive on other parts of the body, but kept the swing brief (in order to lessen the moment of inertia, like a figure skater trying to speed up the rotation).... and since the 'early stage rockets' didn't provide much boost, she had to use the forearm aggressively.

 

[toly]

Peace is better than war!?

Cute question, but my comments were somewhat paraphrased, directed at yours that I've re-quoted. You were dismissing the activity of the bicep as 'not happening around impact', I was making a similar comment about pronation....

English is my third language and it is not very friendly with me. Tiw, sometimes, I just cannot comprehend your comments. Sorry for my pitiable Russian English. But, what can you seriously say about Nadal pronation and internal shoulder rotation?

 

[OrangeOne]

English is my third language and it is not very friendly with me. Tiw, sometimes, I just cannot comprehend your comments. Sorry for my pitiable Russian English. But, what can you seriously say about Nadal pronation and internal shoulder rotation?

There's no war

Mate, if English is your third language you're doing well! I used to know a word in Russian but it wasn't polite

Seriously, and briefly, I think the forehand being analysed was a bad choice! I also feel pronation is a smaller component of spin, well, let me reword, certainly not so much a deliberate component of spin, and not a directly teachable one.

Now can we have a Stoli on ice?

 

[Mr_Shiver]

Like someone else said, I think the amount of pronation depends on the shot. I find that lower shots and those where I don't have time to set up for a full swing that use my of my forearm more than normal. Maybe this is why my follow through is lower on those shots.

 

[toly]

Federer forehand

Nadal's long fast swing, coupled with his grip (strong side of SW) allows a natural pronation after impact. If he adopted an eastern or conti grip, he would HAVE to force the pronation.
My SW grip is similar, I hit 1/2 as hard as Nadal, and my followthru naturally rolls over so the hitting face is facing my opponent, but from the RIGHT side of my body...me lefty. Just a function of the GRIP USED. You have to fight NOT to pronate with strong grips.
And we all know from golf, a strong full followthru insures a replicable stroke.

There's no war

Mate, if English is your third language you're doing well! I used to know a word in Russian but it wasn't polite

Seriously, and briefly, I think the forehand being analysed was a bad choice! I also feel pronation is a smaller component of spin, well, let me reword, certainly not so much a deliberate component of spin, and not a directly teachable one.

Figure 1. Federer forehand
I think Federer, like Nadal, generates very severe pronation and shoulder internal rotation. The main reason for that is (IMHO) Federer wants to produce intensive topspin. Their motions are very similar, but they are using different grips (Eastern/SW).

Now can we have a Stoli on ice?

I’m always ready!!!

 

[toly]

Like someone said I think the amount of pronation depends on the shot. I find lower shots and those where I don't have time for a full swing use my of my forearm than normal. Maybe this is why my follow through is lower on those shots.

Agreed. For instance, If we want to produce pure flat forehand we can forget about pronation, at least before contact.

 

[SystemicAnomaly]

A side bar here (since it really is not germane to the discussion at hand). The biceps are involved in supination primarily when the elbow is bent. When the arm is straight (no elbow bend), the biceps provide little or no assistance to the forearm for supination.

Yes, I agree absolutely. You demonstrate very deep knowledge about this stuff. Do you have any medical background?

I thought that I had answered this but I don't see the post anywhere...

No, I do not have a medical background. Have not even taken an anatomy classes. I picked up much of what I know about this stuff by doing a lot of my own research. I actually figured out the involvement of the biceps in supination by analyzing my badminton backhand.

 

[toly]

I thought that I had answered this but I don't see the post anywhere...

No, I do not have a medical background. Have not even taken an anatomy classes. I picked up much of what I know about this stuff by doing a lot of my own research. I actually figured out the involvement of the biceps in supination by analyzing my badminton backhand.

Thanks. Can you take a look at my thread and give me feedback please? See link: http://tt.tennis-warehouse.com/showthread.php?p=5274865#post5274865