Racket face angle at contact

[jasonfrausto]

It's been a long time since I created a thread and maybe this has been covered more in depth here than what I came up with using the search function, but I wanted to see what the consensus was.

1) What kind of data is out there on the racket face angle at contact for guys like Federer/Nadal/Djokovic on topspin forehands? I've looked at tons of videos the last 10 years and there are obviously variations, but what is the maximum number of degrees the racket can be tilted forward without missing the ball in the net?

2) I've seen data here and there through Google searches, but nothing seems to have been done on the subject since 2006 from what I could tell, and that was around the time Nadal was starting to make a larger impact?

John? Brian Gordon? Anyone? Thoughts on this topic or data that points to how much tilt is too much?

-Jason Frausto

[johnyandell]

Jason,

Great question and great to see you at the Easter Bowl. In the high speed video in the archives you definitely see closed face. But you also see a large number of vertical or close to vertical.

Very hard to give an accurate angle measurement from qualitative video--even as good as our at 500 fps--but I would guess 10-20 degrees is the range that works.
Rod Cross had a complex formula about this in Technical Tennis that involved ball speed, contact height, swing plane angle and racket tilt. I believe his conclusion was that the face would produce topspin without sending the ball into the net under certain combinations of variables.

[klacr]

Jason, it is a fascinating question you bring up. The 10-20 degrees that John mentions seems consistent with the other guesses I've heard from tennis coaches.

To specifically know at each and every moment of contact will be tough. Assuming a player can make perfectly clean contact with the ball near the top of the hoop between the 4th-6th cross in the center plane of their string bed and that the ball they are hitting is approaching them with the same speed and spin each and every time. No doubt there are many variables. Personally, I'd love to see a study done showing the effects on the racquet angle, twist and turn, and swing at impact when returning a heavy topspin forehand from Nadal compared to a much lower rpm forehand of Petr Korda.

If you're in Boca, let's get together and discuss at your leisure.

Kyle LaCroix USPTA
Boca Raton

[stroke]

Very interesting discussion. My non quantitative guess would be the straight arm forehands of Fed, Nadal, and Verdasco allow for the most racquet tilt forward at contact. My thoughts are that the more forward contact position and the technical advantage of the straight arm, which allows for more shoulder pronation into contact, would be the reason for this alleged more forward tilt position.

[DougEng]

Jason,

Great question and great to see you at the Easter Bowl. In the high speed video in the archives you definitely see closed face. But you also see a large number of vertical or close to vertical.

Very hard to give an accurate angle measurement from qualitative video--even as good as our at 500 fps--but I would guess 10-20 degrees is the range that works.
Rod Cross had a complex formula about this in Technical Tennis that involved ball speed, contact height, swing plane angle and racket tilt. I believe his conclusion was that the face would produce topspin without sending the ball into the net under certain combinations of variables.

There were some measurements a while back and I believe 9 degrees was the maximum measured. However, that might be baseline groundstrokes at normal heights. Consider being inside the baseline and on a high ball. Today's players have the ability to take the ball higher than ever; height of contact, spin and distance from the net is important in measurements.

[DougEng]

Measurements

It's been a long time since I created a thread and maybe this has been covered more in depth here than what I came up with using the search function, but I wanted to see what the consensus was.

1) What kind of data is out there on the racket face angle at contact for guys like Federer/Nadal/Djokovic on topspin forehands? I've looked at tons of videos the last 10 years and there are obviously variations, but what is the maximum number of degrees the racket can be tilted forward without missing the ball in the net?

2) I've seen data here and there through Google searches, but nothing seems to have been done on the subject since 2006 from what I could tell, and that was around the time Nadal was starting to make a larger impact?

John? Brian Gordon? Anyone? Thoughts on this topic or data that points to how much tilt is too much?

-Jason Frausto

There were some measurements a while back and I believe 9 degrees was the maximum measured. However, that might be baseline groundstrokes at normal heights. Consider being inside the baseline and on a high ball. Today's players have the ability to take the ball higher than ever; height of contact, spin and distance from the net is important in measurements.

Doug

[jasonfrausto]

Jason,

Great question and great to see you at the Easter Bowl. In the high speed video in the archives you definitely see closed face. But you also see a large number of vertical or close to vertical.

Very hard to give an accurate angle measurement from qualitative video--even as good as our at 500 fps--but I would guess 10-20 degrees is the range that works.
Rod Cross had a complex formula about this in Technical Tennis that involved ball speed, contact height, swing plane angle and racket tilt. I believe his conclusion was that the face would produce topspin without sending the ball into the net under certain combinations of variables.

John,

Nice to see you and get a chance to talk "shop" a bit I'm sure you got plenty of great footage of the next generation of top junior players. I'll definitely check out the book by Rod Cross.

[jasonfrausto]

Jason, it is a fascinating question you bring up. The 10-20 degrees that John mentions seems consistent with the other guesses I've heard from tennis coaches.

To specifically know at each and every moment of contact will be tough. Assuming a player can make perfectly clean contact with the ball near the top of the hoop between the 4th-6th cross in the center plane of their string bed and that the ball they are hitting is approaching them with the same speed and spin each and every time. No doubt there are many variables. Personally, I'd love to see a study done showing the effects on the racquet angle, twist and turn, and swing at impact when returning a heavy topspin forehand from Nadal compared to a much lower rpm forehand of Petr Korda.

If you're in Boca, let's get together and discuss at your leisure.

Kyle LaCroix USPTA
Boca Raton

Kyle,

Thanks for the response, I've seen quite a few different sets of numbers thrown around and I've used measuring tools on 240FPS video that have given me anything from 9-12 degrees depending on the player or shot, but it seems like there are so many variables involved that getting a clear cut answer isn't possible. I'd like to speak or meet with you as I'm living in Delray Beach now. I'll message you.

-Jason

[jasonfrausto]

There were some measurements a while back and I believe 9 degrees was the maximum measured. However, that might be baseline groundstrokes at normal heights. Consider being inside the baseline and on a high ball. Today's players have the ability to take the ball higher than ever; height of contact, spin and distance from the net is important in measurements.

Doug,

I did read that 10 degrees closed would more than likely send the ball into the net as well, but as you've stated court position and distance also play a factor as well. Thanks for your response, much appreciated.

-Jason Frausto

[jasonfrausto]

Very interesting discussion. My non quantitative guess would be the straight arm forehands of Fed, Nadal, and Verdasco allow for the most racquet tilt forward at contact. My thoughts are that the more forward contact position and the technical advantage of the straight arm, which allows for more shoulder pronation into contact, would be the reason for this alleged more forward tilt position.

Good observation, it seems like the factors to the amount of forward tilt on a particular shot could be almost limitless in terms of combinations. This might be the question with no definitive answer?

-Jason Frausto

[giancarlo]

Great discussion as usual.

Would be interesting to see if the new strings allow a player to have a more closed racket face on contact vs. all gut. In general, my feeling is that the new frames and specifically the strings, are turning tennis into a more table tennis like sport. If you ever played a game of table tennis with a brand new pad vs. the older non-sticky pads, then you know what I mean. Every time I watch Federer up-close, I feel like he is applying the spins and angles--that only existed in table tennis--to tennis.

[GeoffWilliams]

Fed does not use the edged spin strings, but he does use 10 string a lings, placed in between 4-6 cross down, every other main at cross. Some say, the string a lings, have an edge, that cuts into the ball, and spacing them like he does, gives an unfair advantage spin wise. His mains snap back more, on the ones not string a linged, while the other ones, grab the ball on the edges of the string a lings. Although, the gut/alu combination, has more rpms than say, rpm blast, on lab tests, due to the teflon coating alu has infused.

[johnyandell]

Here's a low Fed ball. What are your guesses on the angle?

http://www.tennisplayer.net/members/high_speed_archive/phantom/Roger_Federer_HD_HS/index.html?dir=Forehand/RF_FH_Wide&stroke=RFFHWideOpenStanceSide1_250fps.mp4

Here's a higher one that seems more extreme:

http://www.tennisplayer.net/members/high_speed_archive/phantom/Roger_Federer_HD_HS/index.html?dir=Forehand/RF_FH_Wide&stroke=RFFHWideOpenStanceSide1_250fps.mp4

One of the problems when this gets discussed, especially using only still images as "evidence" is that if the ball hits below center, the face will close more and often radically after contact.

On the TW message board you see these pics posted all the time "proving" that the face closes 45 degrees, etc...

[gzhpcu]

But won't the angle vary a bit? Nobody can hit with a perfectly perpendicular face.

Also doesn't the intent affect the angle? If I am going to hit a forehand slice, the face of the racket closes... If I am going to hit topspin the face closes... If I am going to hit flat, the face will remain most perpendicular to the court...
As John mentioned, pre-impact most be captured, not post-impact, since anything above or below the racket axis will cause it to turn...

So, isn't it just a question of letting it happen?

[10splayer]

But won't the angle vary a bit? Nobody can hit with a perfectly perpendicular face.

Also doesn't the intent affect the angle? If I am going to hit a forehand slice, the face of the racket closes...

If I am going to hit topspin the face closes... If I am going to hit flat, the face will remain most perpendicular to the court...
As John mentioned

, pre-impact most be captured, not post-impact, since anything above or below the racket axis will cause it to turn...

So, isn't it just a question of letting it happen?

No, I would say the "path" determines the spin. For instance, a flat shot is hit with a perpendicular face (more or less) and a "shallow path". A topspin shot is hit with also a perpendicular face (within this ten degree margin) and a "steeper" path.

Further, I would guess that the racquet face angle has more to do with the desired trajectory of a shot given the path...Hence the reason that the face can be a bit closed on higher balls. (topspin)