Groundstroke Velocities Soar in Pro Tennis

[johnyandell]

So some contary information. Just got back from speaking at Vegas at USPTA National. My friend Dave Ramos from USTA was there. They have complete access to all shot spot data and a lot of inside info on the system. Dave does not believe it is accurate above 115mph or 3000rpm.

[doctorhl]

Thanks!
Speaking of which, watch this rally in table tennis.
The table is clearly too small for their game.

https://twitter.com/NYinLA2121/statu...365622273?s=03

Wow! If tennis goes down the road in that video, then.........

[jimlosaltos]

Great stuff Jim! I just had a flashback of how elite table tennis evolved to having players standing further back from the table edge and increasing speed, spin and net clearance height over the years. Paddle technology also played a part in this change. This data seems to have some relevance in constructing training methods. Will we see higher net clearance averages as speed increases? Will we see higher ball bounces? Will the Shapolov jump become routine? Will Nadal- types demand that the minimum required barrier distance behind baselines be extended?

Thanks!
Speaking of which, watch this rally in table tennis.
The table is clearly too small for their game.

https://twitter.com/NYinLA2121/status/1422027318365622273?s=03

[doctorhl]

Great stuff Jim! I just had a flashback of how elite table tennis evolved to having players standing further back from the table edge and increasing speed, spin and net clearance height over the years. Paddle technology also played a part in this change. This data seems to have some relevance in constructing training methods. Will we see higher net clearance averages as speed increases? Will we see higher ball bounces? Will the Shapolov jump become routine? Will Nadal- types demand that the minimum required barrier distance behind baselines be extended?

[jimlosaltos]

Jim, any observations about ranges of height of ball above the net in relation to spin or speed rates?

Hello. Good question. It's great that RG/InfoSys includes that stat, heigh above net in the data points, isn't it? When Berrettini or Tsitsipas hits a 129 MPH groundstroke at 3-5 feet over the net they're getting tremendous margins as opposed to a flatter hitter such as Medvedev or Bautista-Agut. But then the upward racket head speed they have to generate is also tremendous, so what's the trade off there? We've seen over the years how Fed can look great, then suddenly hit a patch where he completely shanks forehands into the stands. Only milliseconds separates a brillant winner from a fan souvenir.

I didn't create tables of the net-clearance-height but from observation most of the huge forehands had a great deal of clearance. There were a few forehands in the 120 MPH range that had lower clearance. From memory, those were inside-out forehands from the likes of Djokovic and Zverev.

[doctorhl]

Jim, any observations about ranges of height of ball above the net in relation to spin or speed rates?

[jimlosaltos]

Hard to believe the bhs got to that level of speed. Nuts if that’s the case

Agreed. Now, if we assume the ball has an impact, as I postulated from the NYT's article, then Zverev's backhands would "only" be around 120 MPH with Wimbledon's heavy, dead balls. Which is still hard to wrap one's head around.

If anyone has any explanations, I'd love to hear them.

[jimlosaltos]

Is there any reasonable speed/spin ratio to determine an objective "heaviness" of a ground stroke?

None that i know of. Love to hear of a way. I assumed it would be easy to calculate the kinetic energy from velocity, from rotation and combine those but apparently not. I discussed this with a Japanese physicist who said there is a discussion board in Japanese on this {No, really! } and physicists there can't agree on what to do. I am both disappointed and reassured <g>.

Apparently, some of those physicists claim that when people say "Returning Pete Sampras' serve is like hitting a bowling ball" that it isn't real, they're just mishitting the ball. I guess if they can't put it in an equation it's not real <g>.

[aligorec]

Is there any reasonable speed/spin ratio to determine an objective "heaviness" of a ground stroke?

[jeremy93]

Hard to believe the bhs got to that level of speed. Nuts if that’s the case

[jimlosaltos]

Finally, here is the shot where Hawkeye and Infosys show Sasha Zverev's forehand reaching 136 MPH vs Tsitsipas.

ZverevFhd136MPH_3696RPM_RG21.jpeg

[jimlosaltos]

[jimlosaltos]

Here for comparison with the newer Roland Garros numbers are the full stats released by GIG, the tennis data arm of Tennis Australia, spanning 2012-2106 on Australian Open "Show Courts", the only ones that had Hawkeye. Both the Aussie and French data comes from the same technology, Hawkeye.

The images are in the next reply. Source: New York Times.

[jimlosaltos]

While Djokovic generally hits flatter than the biggest spinners, and doesn't match Berrettini or Tsitsipas' sheer velocity, he can top 120 mph as he did on several shots at Roland Garros including this against Musetti.

filedata/fetch?id=94851&d=1627838607&type=thumb

[jimlosaltos]

It's been claimed that Ash Barty hits with some of the, if not the, highest spin on the WTA. These stats support that. Her 3,411 RPMs on a forehand is 400 RPMs higher than any other WTA player at RG, with Iga Swiatek and Sakkari both reaching roughly 3,000.