federer forehand - racquet head tilt

[davehagler]

gotta preface this by saying this is about as good as articles and footage get. Always knew that Federer had more variations than anyone but the more you see of him the more you have to shake your head and say WOW! When you look at racquet tilt some of the the factors involved are the foreward velocity of the racquet, if the ball is dropping or rising as it is being contacted, the trajectory, type and amount of spin on the shot and the swingpath of the racquet. That's a lot of stuff to think about and I am probably missing something. If someone stands halfway between the service line and the baseline and you feed them a ball with tons of topspin and the contact point is fairly high then you can ask them to try to drive the ball into the top of the net and my guess is they will hit virtually all of their shots into the court. Since I do not have a 250 frame/sec camera it is difficult to see what is actually happening but one would think that there is generally some racquet tilt involved. The father of 2 junior players I coach both have PhD's. in Physics so I will get their input on this.

Any thoughts anyone?

[lukman41985]

I think that if a player is standing at the mid-court and gets a high bouncing ball, at shoulder-level or higher, the closed racquet face and/or a high-to-low swing path is necessary to get the ball back down into the court. Brett Hobden of modern tennis refers to this forehand variation as the dip drive. Hewitt uses this technique a lot. You'll see it when he hits his forehand and the swing almost looks like a low forehand overhead. It's pretty crazy. Looks sort of ugly but who cares, it works! I think that in this scenario a level/low-to-high swing and/or perpendicular racquet face would send the ball long.

[mntlblok]

Physics answer?

I was so thrilled to find the Tennisplayer.net site today. I had just sat down to go through all the videotapes that I had saved from this year's grand slams to find all the "super slow mo's" and copy them to one tape when I decided to give the web one more look for such video. To my great surprise, I found this!

I've so far only looked at the two articles on Roger Federer's forehand. What wonderful stuff!! I'm so glad to learn that there are others out there as anal retentive as I. :-) I could talk about those articles for hours.

For now, I'll just throw my two cents worth in on my theory about how a ball can be hit with an upward trajectory with a closed face at impact, even when a ball is not taken on the rise.

I had argued this repeatedly with local pro's because I had, through a ridiculous amount of experimentation, come to the conclusion that the only way that I could control the trajectory of my topspin forehand was to hit it with what felt like a closed racquet face. Then, after seeing various super slow-mo's of topspin shots on TV, I concluded that that is actually what often happens.

Physics suggests that it can't happen - if the racquet face is considered a "solid" surface. However, my theory is that as the tennis ball is flattened and squished at impact, parts of the ball actually go *through* or *between* the strings. If that happens, then even if the *face* of the racquet is closed, there are actually a number of strings that *under* parts of the ball, and the upward path of the racquet on a topspin stroke would allow *those* parts of the strings to *lift* the trajectory of the ball.

It happens that I've also recently purchased a copy of "The Physics and Technology of Tennis" by Brody, Lindsey, and Cross. Note the photo on the upper right on page "v" in the table of contents showing the ball squishing out through the strings.

So, that's my theory. What do you think?

Kevin Bryant
Savannah

[johnyandell]

Kevin,

Not sure what the squish has to do with it. We have an article in progress from Rod Cross and I think that in the second book he wrote with Crawford, Technical Tennis, he also goes into why this works. Some combination of speed, spin, trajectroy and swing path--and there is probably an equation.

To be honest I am not sure what it all means from the players point of view. My thought is that it is definitely happening at high levels, but not sure if it's intentional or can be trained. Honestly my thoughts are still in process there.

One person who does have some clear ideas about it though is our contributor Kerry Mitchell. Check out his articles on grips in Classic Lessons. He address this specificaly.

Glad you are enjoying the site!

Regards,
John Yandell