Supination/Pronation

[gzhpcu]

I discussed the role of supination-pronation with Brian Gordon some years back.

Here is the thread: http://www.tennisplayer.net/bulletin/showthread.php?t=388&page=2

Some relevant quotes:

Supination (an external rotation of the forearm as if one were holding a bowl of "s(o)up" in the palm of their hand) is a natural, and perhaps the most important, attribute of the vertical component of the looped back swing path. In other words, the forearm will be rotated externally to facilitate the downward racquet motion - EVERY looper does this to some extent.

The importance relates to the muscular conditions of the internal forearm rotators which pronate the forearm near the contact point and are the source of the most efficient action to generate the vertical racquet speed component needed for topspin. These internal rotators are contracted to slow the afore mentioned external rotation, prior to actually accomplishing internal rotation (pronation) of the forearm. This slowing contraction is a "pre-tensing" which eliminates the problem of TIME to maximum force production found if starting from a relaxed state. Also, it does activate most, if not all, other beneificial aspects of the "stretch-shorten" cycle if executed correctly.

In short, the supination/pronation chain of events is a counter movement pattern that greatly facilitates action of the forearm internal rotators. We routinely quantify the extent to which this mechanism is used as an indicator of prowess in stroke mechanics at our player development center. It is extremely important on the forehand, backhand, and serve, it is independent of grip style, and having identified this years ago I've always been surprised the tennis gurus had not noticed it earlier - nice work in recognizing its relevance

Yes - on a serve supination precedes pronation and is utilized in the early portions of the upward swing phase as the racquet completes the lateral sweep exiting the back swing loop. It is less pervasive than on ground strokes because the role of pronation on the serve is relatively smaller.

And yes - on a backhand the sequence is pronation/supination - however it is supination/pronation for the top arm on a two hander.

 

[stormholloway]

I've been very interested in supination on serve too. I don't know how much or how actively I'm supposed to do it. You don't hear a soul talking about it around here.

 

[gzhpcu]

I've been very interested in supination on serve too. I don't know how much or how actively I'm supposed to do it. You don't hear a soul talking about it around here.

It is useful at the bottom of the racket drop, and when starting to come up, because it keeps the racket away from the body, and to the right.

 

[SystemicAnomaly]

Interesting read. Have been aware of supinations in tennis since the 1980s but they are spoken of very rarely by tennis players. In badminton, supination is very well known by many since the badminton backhand is inherently a very weak shot -- players must be made aware of an external rotation to develop a proper badminton BH. The average tennis player learns to supinate but is usually not aware of it at all.

 

[SystemicAnomaly]

The idea of supination really isn't all that new. First heard about the concept some 25 years ago when I learned about hitting a badminton BH. James Poole, a US badminton champion back in the 1950s & 60s, wrote about the importance of forearm rotations in the late 60's (or early 70s). I believe it may have been his PhD thesis way back when. I had posted a little bit about this about 7-8 yrs ago:

badmintoncentral.com/forums/showthread.php?p=15429

badmintoncentral.com/forums/showthread.php?p=48164

.

 

[gzhpcu]

I think this has become an issue with today's modern forehand. Earlier classic forehands did not use a linear swing, but a circular swing.

 

[Xisbum]

This is an interesting forum. I never thought of the supination part in hitting the ball and probably spend too much time worrying about the pronation.

Strange thing is I have to worry about supination with my feet because of high arches.

 

[mrcalon]

If you watch Rafa's videos, it looks like he's pre-supinated in the entire backswing suggesting he's not using any SSC from the forearm at all. Same with Murray. Other guys like Fed and Verdasco look to be in a neutral position between full pronation and full supination right before they start to loop.

IMO an SSC of the upper arm from internal to external rotation is a stronger contributer, at least based on what I can see in videos.

 

[gzhpcu]

Watch Nadal's forehand. Notice how at the end of the backswing, just prior to hitting, he supinates his forearm, stretching it, so as to get a more violent pronation during impact.

http://www.youtube.com/watch?v=inQvbT8uEGk

For example at 10 seconds and 28/29 seconds...

 

[Tennis Dunce]

Hmmm...very interesting. I'll consciously focus on supination when I hit the courts tomorrow. I'm pretty sure its inherent, with time, but if its lacking then I've been cheating myself for a long time. I could see how supination could easily add 5 mph to serve.

Thanks

 

[SystemicAnomaly]

^ Not sure how one would even be able to pronate the forearm on the serve without first supinating. If you are already getting a sufficient pronation, then you are undoubtedly getting a sufficient supination as well.

 

[Tennis Dunce]

^^ Yes...but maybe I need to exaggerate the supination a little more?

 

[stormholloway]

When I supinate during my racquet drop on serve, I get a pain in my shoulder. Anyone ever experienced this?

(Slightly off topic I know.)

 

[J011yroger]

I am of the opinion that supination should be passive in the serve/FH as you start to pull your shoulder into the stroke, and let your arm/racquet lag.

J

 

[mrcalon]

Watch Nadal's forehand. Notice how at the end of the backswing, just prior to hitting, he supinates his forearm, stretching it, so as to get a more violent pronation during impact.

http://www.youtube.com/watch?v=inQvbT8uEGk

For example at 10 seconds and 28/29 seconds...

IMO think he's already supinated by 0:06-0:10. Look at where his thumb is relative to the outside (medial?) of his elbow/upper arm. His arm is in a position sort of like at the bottom part of a bicep curl (coincidentally known as a supinated position, with palm facing up). If he has pronated, his arm would be in the position of a reverse curl (palm facing down).

What we're seeing at 0:10 is external rotation of the upper arm. Hard to see in that vid because of the angle, but the elbow goes from pointing behind, and then down towards the court at 0:10.

 

[gzhpcu]

At 6 seconds:

At 10 seconds
first:

then:

This quick movement looks like supination to me...

 

[mrcalon]

IMO that's the upper arm causing the movement, not the forearm. Technically he isn't supinating.

Here is a picture analogous to what his forearm is locked in. His thumb is the outside of the elbow.

http://rehabworks.ksc.nasa.gov/images/rehabworks/education/protocols/pvc_supination.jpg

Same position as this -

http://img412.imageshack.us/img412/9804/nadala.jpg

You have to watch the "supination" relative to the upper arm. If the forearm stays fixed relative to the upper arm, there's not really any supination there. For example, get in a position like the guy in my picture by placing the top of your forearm on a table. Now try supinating further. It's impossible right? Only way to go back any further is by rotating at the upper arm, from the shoulder.

 

[gzhpcu]

I am trying to duplicate the motion in front of a mirror. If I extend the arm like Nadal at the start of the 10 second image and try to get the racket in the position it finds itself at the end of the 10 second image, the only way I can do that is by rotating my hand clockwise. This creates movement in the lower part of the forearm and gradually diminishes as it goes up to the upper arm. Try it yourself. Seems like supination to me, or am I misinterpreting it?

 

[mrcalon]

I look at the elbow as the reference point. After extending the arm, i think his elbow is pointing behind him. After the stretch, it points more towards his body.

Hard to tell from the youtube video so here's some caps i took from John Yandell's site tennisplayer.net (the video is RNFHCenterSide1.mov, John if you object to these pics going up just let me know and I'll pull these caps down).

http://img135.imageshack.us/img135/9848/nadal1.jpg
http://img17.imageshack.us/img17/9295/nadal2g.jpg
http://img5.imageshack.us/img5/4186/nadal3q.jpg

Try it in front of the mirror. Start with the elbow pointing behind you with forearms supinated. Next, extend arms down. Then rotate the elbows in. IMO that's what's happening at the bottom of the backswing. If it was only supination, then the elbow wouldn't change it's orientation.

 

[gzhpcu]

Hmmm... see what you mean... think you are right...

 

[mrcalon]

additionally, if you watch some more vids on tennisplayer of the forward swing (i suggest looking from the frontal angle), the forearm doesn't rotate internally independent of the upper arm (i.e pronate) until well after contact. Evidence that pronation doesn't really play much of a factor in the vertical component. I think it's just part of the deceleration.

However watch the elbow orientation, and you'll see upper arm internal rotation starting well before contact.