Have a Question for Me?

[erland]

Thanks for the insight on the grips. Am I incorrect on the grip description for the top hand on the backhand of a right-handed player - count from bevel 1 clockwise so the index knuckle (looks like) on 6 for Novak and (looks like) on 7 for Andre?

As for stopping Fed during a point for pictures of his grips - yeah, that might be a tad rude - but, I thought with your fame and influence in the tennis teaching world, you could convince him and others to let you snap some shots while chilling at tournaments with them!

As a backup plan... Can you zoom-in more during filming to get these shots? A great example of this is in your "Arm Action" clips which get in closer to the player. If you take a look at Novak's regular archive FH page and at clip "NDFHInsideOutArmActionSide2", it has the view looking toward the back. At the end of the swing when the hand is turned over and slowed down in this view you can see the handle and index knuckle placement best. If you go thru this part frame by frame, you can isolate a frame that shows it on 4 1/2 about as clearly as can be seen in all clips. A few good, even more close-up zooms like this, could give us all the player's grip structures nicely.

By the way, speaking of really clear pictures, are you going to get more hi-def clips like that of Fed for Rafa, Novak and others? Those are really awesome clips!!

Thanks for all you do for tennis and for crazy engineering types like us that what to understand how everything works and make it even better if possible. Since I am a science teacher also, maybe that helps explain why I have this infatuation with tennis mechanics?!

Erland

[johnyandell]

Yeah that's one of the points of the arm action footage. We have more high def clips to put up of the other plays and will be over the next year. Right on the bevels at least as close as I can see it.

[GeoffWilliams]

John, how did you like my forum post on getting the best string job for your game?

[johnyandell]

geoff, trick question--you know i only feel i need to read it.

[lobndropshot]

Software options

What are the analytical software options that can use quicktime video files?
Thanks

[johnyandell]

Dartfish can although the older files have to be converted. There is an article on doing that in teaching systems. In my own work I simply use the QT windows and open them side by side. You can open multiple windows at the same time.

I personally don't like to draw lines, do voice over, etc, but if you want to do that there is Dartfish and another program called motion pro which is less expensive. I think it can read all QT files or converts them automatically. I am sure there are more out there as well.

[tennisfan04]

Serve count versus pitch count

Hi John,

I understand that young baseball players are told not to throw more than a certain number of pitches as they are growing up to protect their arm. Do you know what those numbers are?

How do those number relate to the number of serves that junior players routinely do when they play 3-4 matches over a weekend at a typical USTA Junior tournament?

Is there a "serve count" that you would advise junior players to not exceed per day?

Thanks

[johnyandell]

Great Great question. Never heard of it applied to tennis. I am not an expert on injuries or physiology. So no real opinion here other than the obvious--if it's tired hurt or very sore, stop! Heading to Easter Bowl. If I run into some USTA coaches I'll ask.

[bowt]

Hi John,

http://andrevazpinto.blogspot.com/2011/04/sarah-campion-forehands-at-500-fps.html

if you were going to analyse or give advice to this player what would you say?

Thanks

[johnyandell]

Two things. I'd want to be asked by the player or coach. But second even though that is some gorgeous high speed video, unless you can advance it frame by frame you really can't make a good analysis of the stroke positions.

[bman]

here's an interesting question. I have a player (19 year old male, low level tournament player) whose off arm is not "tucked" at contact point on the serve, but rather it is up in the air, so that both arms are up in the air, in triumph like Rocky Balboa at the top of the art museum steps. My question is

1) Does this need to be fixed?
2) How would you go about fixing it?
3) This seems fairly rare, is it mainly an issue of lack of coordination?

Thanks

[johnyandell]

It couldn't be helping and might be hurting. Very hard to guess since there is no video. Have him grap his shirt with his hand as he starts the upward swing.

[nabrug]

Did you change your point of view?

1. John Yandell 18-9-2009
"Regarding feeling and strokes.

I believe kinesthetics and visuals are two halves of the same whole. The image or the position leads to the feeling. I've said that repeatedly and written it in my book."


2. John Yandell - 0ktobre 2010 - The Upward Swing: Federer's Serve in High Speed and High Def
"Second there is a very complex interplay of movements that creates that speed in that fraction of a second, movements that include the upper arm, the elbow, the forearm, the shoulder and the wrist. These body segments are all moving at the same time, and also changing shapes and positional relationships with each other.
You can forget about seeing all that accurately with the naked eye. Even high speed video, as we will see, still leaves issues open to question and disagreement. So yeah, passionate, knowledgeable people come to different conclusions.
I’ve written about some of these debated issues before in articles on the movement of the wrist (Click Here), and on the motions of Federer (Click Here), Roddick (Click Here) and Sampras (Click Here). I’ve also gotten into many, shall we say, animated discussions, on internet message boards and at coaching conventions over what actually happens.
Then there is the related but not identical issue--how to make what actually happens happen. This is an equally puzzling and possibly even more debated question. And the one that really matters for players who want to improve their serves."

In my opinion you changed your opinion drastically? Can you tell sg. about the contributions what led to your change?

[johnyandell]

No my opinion is the same.

[nabrug]

No my opinion is the same.

That is very strange.

Under 1 you say: "The image or the position leads to the feeling."

Under 2. you say: "These body segments are all moving at the same time, and also changing shapes and positional relationships with each other." Your conclusion there for is excellent "Then there is the related but not identical issue--how to make what actually happens happen."

In my opinion 1 and 2 are contradictionary. It can't be both. So I understand you still believe in the first. Than why did you write the second piece of text.