Pronation to supination to pronation

[bkc]

http://www.palmbeachpost.com/sports/content/sports/tennis/davis_cup/roddick_serve.html

Look at this clip of Roddick's serve and count the frames. Now look at frames 10, 11 and 12. Frame 10 shows beginning of the swing pronation. Frame 11 shows end of the backswing supination. Frame 12 shows close to contact pronation. These three frames show the essence of the swing. The swing starts and ends with these 3 frames. The rest of the swing before and after these 3 is of secondary importance. These 3 frames will look the same for all good servers. Everything else will be different.

The topspin forehand will be the same for these 3 frames, except the arm is out to the side and the opposite side of the ball will be getting brushed.

The one-handed back hand is an opposite motion, ending in supination.

This is the foundation of hitting a tennis ball. When you have a bad day, you aren't doing this. Some pros (or most) don't know they are doing this. They just know the feel of it. They couldn't teach you how to hit (very easily).

When it seems like you are hitting with power with little effort, you are doing this. Its because you now have racquet speed.

This is how they pitch in baseball and how they swing the bat.

This is most of what you need to know to play. The rest proceeds from this knowledge.

Does this sound arrogant, or what?

 

[All Court]

You're pretty much right!

But one thing -with the Western grip, Semiwestern, or more extreme grips, the racquet face closes naturally. So you pretty much naturally pronate at the end.

So the last pronation part shouldn't be done consciously.

But it's definitely good to start with the racquet face pointing down! It helps get topspin and start accelerating the racquet. So the pronation to supination you see is the person driving the racquet butt forward from the "racquet face pointing down position" (LOL, for lack of a better term), and the racquet moves to be pointing side to side.

So you stumbled onto a good point with the "pronation to supination" part, or starting the swing from when the racquet face is pointing down! But the last pronation part shouldn't happen consciously, if anything it should happen naturally.

Nice analysis!

 

[bkc]

But it's definitely good to start with the racquet face pointing down!

You mean on a forehand or a serve?

 

[All Court]

Ah, on a forehand. On the serve, the backswing/start of the motion shouldn't really matter as long as you somehow get your arm in a fully dropped position.

 

[bkc]

Ah, on a forehand. On the serve, the backswing/start of the motion shouldn't really matter as long as you somehow get your arm in a fully dropped position.

On the forehand, I think the reason for starting with the racquet face down and the head pointing to the net, is that this way you are starting out in pronation. Then as you take your backswing you naturally rotate to supination, and then naturally again to pronation as you swing forward. The only part you have to think about is the starting position and the rest becomes automatic.

On the serve, the position that is analogous to the forehand-face-down-pronation-position is that position that Roddick gets in where the elbow is bent, the racquet is straight up, and the face of the racquet is sideways away from the body (pronation).

Not sure what you mean by the "fully dropped" position.

 

[Bungalo Bill]

http://www.palmbeachpost.com/sports/content/sports/tennis/davis_cup/roddick_serve.html

Look at this clip of Roddick's serve and count the frames. Now look at frames 10, 11 and 12. Frame 10 shows beginning of the swing pronation. Frame 11 shows end of the backswing supination. Frame 12 shows close to contact pronation. These three frames show the essence of the swing. The swing starts and ends with these 3 frames. The rest of the swing before and after these 3 is of secondary importance. These 3 frames will look the same for all good servers. Everything else will be different.

First off, you are missing an awful lot of frames. I have slo-mo video of Roddicks serve. Very clear and very precise thanks to John Yandell. Your claim is that the arm pronating/supinating is a HUGE source of power. It is not. The source of power is coming from the range of motion in the "backscratch" or the shoulder area which is being LOADED in frames 10-12. The arm is relaxed and is going for the ride.

Frames 11-12 tell the whole story of how the lower body helped transfer kinetic power. In the first few frames you will see Roddicks knees bend out and placing pressure along the front side of his body. Notice that his elbow is away from the body and rotates internally.

Secondly, it is the arm extending that adds additional power (frames 11-12). Since you are missing a lot of frames here you can only see this with his arm fully extended and the ball is going towards his opponent. Pronation and/or supination should happen naturally and it is not a big source of power but allows the kinetic energy to flow efficiently.

The topspin forehand will be the same for these 3 frames, except the arm is out to the side and the opposite side of the ball will be getting brushed.

The one-handed back hand is an opposite motion, ending in supination.[/quote]

Sometimes and it is not necessary. Many good onehanders hit with the palm facing down in the hieght of the followthrough. It is what many call "seeing the sun through your strings". Supination does happen when there is a lot fo rotational forces in the forearm are to get the racket head around. These players usually play with a full eastern or extreme eastern onehander.

This is the foundation of hitting a tennis ball. When you have a bad day, you aren't doing this. Some pros (or most) don't know they are doing this. They just know the feel of it. They couldn't teach you how to hit (very easily).

No it is not the foundation. The foundation is in the legs and using yoru hips and torso area appropriately. Pronation and supination happens naturally and a player thinking about this fine motor skill area to "fix" their stroke is asking for trouble. Pronation and supination is a delicate area and since it is not the soource of where power comes from it should be treated as a movement that allows ebergy to flow through naturally - period.

When it seems like you are hitting with power with little effort, you are doing this. Its because you now have racquet speed.

Again, racket head speed does not come from pronation and supination. Racket head speed for the forehand comes from a players ability to thrust the elbow FORWARD. It comes from the solid rotation of the shoulders. It also comes from the use of the wrist release which is also a forward move. All of this comes from ones ability to generate kinetic energy from a solid foundation which starts with the feet.

This is how they pitch in baseball and how they swing the bat.

What? Huh?

This is most of what you need to know to play. The rest proceeds from this knowledge.

Does this sound arrogant, or what?

You really need to go back and study players hitting balls with more then a frame by frame powerpoint presentation with missing frames.

Baseball pitcher's loading of the shoulder and the elbow area are the keys to power. A baseball pitchers range of motion allows them to slingshot the arm and hand forward longer and faster. The pronation/supination needs to be left alone so the arm can work naturally.

I am really hoping people don't buy this. They are heading for complete disaster executing their strokes. They will be focusing on a very fine motor skill area and missing the boat on easier and more appropiate ways to generate power. Players who believe you will run out there playing around with this area will also run the risk of injurying themselves because no one will be there to warn them that they are forcing the muscles in this area to move.

 

[bkc]

Pronation and supination is a delicate area and since it is not the soource of where power comes from it should be treated as a movement that allows ebergy to flow through naturally - period.

Agreed. And I don't think you can think about it as you are swinging. You can think, however, about what your preparation is before the swing. The forearm rotation then occurs automatically. But not if you don't start out in a way that let's it happen.

 

[Longbow]

I agree that there is a pronation-supination-pronation motion in topspin-emphasized forehands.

If you look at forehand backswings of some younger generation pros, such as Jack Sock and Kyrgios, they really exaggerate the pronation motion when taking back the racquet. For example, Jack Sock moves his wrist position in a full loaded pronated stage such that his wrist is above his racket head and his racket face pointing backward. Personally I think the fully pronated preparation helps the next stage of supination and lagging the racket. The result is an explosive high-rpm topspin forehand.

 

[RetroSpin]

Your claim is that the arm pronating/supinating is a HUGE source of power. It is not. The source of power is coming from the range of motion in the "backscratch" or the shoulder area which is being LOADED in frames 10-12.

I agree with your analysis, but I assumed the OP was using a shorthand description of wrist positions rather than saying you use conscious wrist turning to generate power.

Anyway, I thought he did a good job of isolating three critical positions. Half of rec players do not know how to get into these positions.

 

[Chas Tennis]

I agree that there is a pronation-supination-pronation motion in topspin-emphasized forehands.

If you look at forehand backswings of some younger generation pros, such as Jack Sock and Kyrgios, they really exaggerate the pronation motion when taking back the racquet. For example, Jack Sock moves his wrist position in a full loaded pronated stage such that his wrist is above his racket head and his racket face pointing backward. Personally I think the fully pronated preparation helps the next stage of supination and lagging the racket. The result is an explosive high-rpm topspin forehand.

This is an old thread, 2005. There have been many discussions to illustrate that the term 'pronation' is not correctly used in tennis and that this incorrect use is very misleading.

Very often in tennis discussions the term 'pronation' is not used in a defined way as in kinesiology. Very often pronation is used erroneously to mean a rotation seen at the hand. That rotation when the arm is near straight is usually caused by internal shoulder rotation (ISR) or a combination of ISR + pronation. When the elbow is bent there is no mistaking ISR and pronation. See instructional videos on measuring pronation and ISR. Likewise, supination is muddled with external shoulder rotation (ESR).

The defined use of the terms is available on Google along with their use in anatomy and kinesiology. Not using the defined usage clearly falls apart when you try to analyze the serve and the elbow is bent. The same thing probably happens for the forehand when the elbow is bent. For example, with a bent elbow when Sock uses pronation on a forehand his hand rotates. Again with a bent elbow, when Sock uses ISR on his forehand forward swing, his entire forearm is propelled forward.

With a near straight elbow, Federer's ISR and pronation have about the same effect at the hand. It is difficult to know what is rotating the hand and very careful measurements using high speed video have to be done to separate ISR from pronation. Markers on the upper arm and forearm make separating pronation from ISR much easier.

An excellent college text on kinesiology is the Manual of Structural Kinesiology, 15th ed., Thompson, Floyd. Older used editions of this text are very low cost.

 

[Longbow]

Chas, really appreciate your insight and clarification re pronation vs ISR. I agree that "pronation" is kind of a misnomer. My wild guess is that Sock's backswing is a combination of pronation and ISR, probably more ISR/ESR transition than pronation/supination transition. The ISR/ESR part of his motion prevents over-stressing the wrist, even though his forehand seems so "wristy."

 

[geca]

OP is correct, but can be misleading.

most amateurs end up with the wrong hand action if you tell them about supination and pronation.

supination and pronation does happen in the windshield wiping action, but they are the slave. the master is actually the external/internal shoulder rotations. The shoulder rotations contribute more because the radius is longer.

also if you teach amateurs about shoulder rotations, they are less likely to flip the racket face.

 

[Chas Tennis]

When I hear word descriptions of tennis strokes I am often uncertain of which part of the stroke the description applies to, especially since even individual players use more than one forehand techniques. Videos together with the word descriptions are much more complete.

I don't know the variety in Sock's forehands. ?

Time vs Joint Motion for first forehand.
4-8 sec Pronation
9-10 Supination & ESR (external shoulder rotation)
10-11 ISR (internal shoulder rotation)
11 Impact. Lower ball.
11-on Most visible ISR and Pronation occurs after ball impact in the follow through. (I define 'follow through' (FT) as after impact. FT does not matter to ball impact and can be done in different ways so I don't study or know much about it.)

Keep in mind that what is important is the racket head motion only during impact. ISR can develop speed rapidly in a short distance but other racket head motions may have higher velocities for the above forehand. I believe that the ISR gives mostly the upward component of string motion. Racket head motions in the follow through often get attention but the less visible string motions during impact is not often commented on.

There is a higher ball later in the video that looks different.....

You can identify joint motions vs time (or frame) and come up with time lines for each stroke, incoming ball height.......... Time lines showing joint motions are probably a very good indicator of stroke quality since they incorporate racket head speed.

Kinovea, a free open source video analysis application, allows video labels and key frames, etc, to show details of time lines. Frame count or millisecond time scales can be applied to the original video.

 

[Chas Tennis]

...............................................................

supination and pronation does happen in the windshield wiping action, but they are the slave. the master is actually the external/internal shoulder rotations. The shoulder rotations contribute more because the radius is longer.

......................................................................

The radius of what is longer?

For the serve, the 'radius' is the perpendicular distance from the rotation axis (extended) of the upper arm to the center of the stings or to the impact location. When the elbow is near straight, as for impact on the serve, the radius of ISR and pronation is the same radius. It is formed by the forearm-to-racket handle angle. Bent elbow takes more explanation.

 

[RetroSpin]

I've looked at a lot of slo-mo pro FH's and I'm just not seeing that much ISR. I guess Sock uses it. There is some on follow through, but it's hard to tell if ISR initiated the WW movement or if it is more passive.

 

[Limpinhitter]

I've looked at a lot of slo-mo pro FH's and I'm just not seeing that much ISR. I guess Sock uses it. There is some on follow through, but it's hard to tell if ISR initiated the WW movement or if it is more passive.

Lendl and Sampras used more ISR and ESR in their forehands than most present pros. Their flying elbows are a giveaway of that. But, they used less forearm pronation/supination/pronation.

 

[Chas Tennis]

Lendl and Sampras used more ISR and ESR in their forehands than most present pros. Their flying elbows are a giveaway of that. But, they used less forearm pronation/supination/pronation.

How or when does the elbow "fly" to indicate ISR and ESR for Sampras or Lendyl? The shoulder and elbow could stay in the same location and do ESR and ISR.

Have videos? What time?

 

[Limpinhitter]

How or when does the elbow "fly" to indicate ISR and ESR for Sampras or Lendyl? The shoulder and elbow could stay in the same location and do ESR and ISR.

Have videos? What time?

Leading with the elbow on the backswing and forward swing of a forehand generates ISR and ESR. The forehands in your video are casual practice swings which are not fully representative of his forehand, or the degree of his ISR/ESR that he generates, in competition. Unfortunately, there aren't nearly as many examples of close up forehands of Lendl and Sampras as there are of more recent players, but, here are a few of what I think are more representative Lendl forehands:

Sampras forehands:

https://www.youtube.com/watch?v=QLyj8tuZMLM

 

[Chas Tennis]

I'm sure that some or a lot of ESR & ISR occurs during the forehand. I don't understand how 'flying elbows' (high speed elbows?) identifies and makes ESR & ISR stand out. I think that the elbows could have high speed and there could be no ESR & ISR, depending on the joint motions and where the masses of the forearm and racket are when the elbow accelerates.

Clear high speed videos often allow seeing the ISR directly by the shadows at the elbow. If players want to see their own ISR/ESR and pronation they should put some tape markers on their upper arm just above the elbow. Markers at the wrist also.

If the elbow is bent the angle of the forearm can show ESR & ISR. Based on forearm angle Sampras looks (right to left) -- 1- ISR position down from horizontal, 2- less ISR position?, 3 - ISR position near neutral, forearm horizontal, 4 - ESR position, __ from 1 to 4 he did net ESR joint motion___ 5- More ESR? Same as #4?

The angular positions of ISR & ESR are normally measured with the elbow at the side as in this video. Zero degrees is defined with this body position not as seen in the Sampras video.

I assumed the upper arm was horizontal and 0 degrees was with the forearm straight forward, horizontal. For Sampras's forehand, there were some adjustments and guess estimates for ISR & ESR angles since 0 degrees is not defined.....

The high speed video should be viewed to see all that happens between #4 and #5.