Have a Question for Me?

[stotty]

Post numbering seems locked

It might just be me but everyone's posts seem to be locked on the same number:

bottle's 2566
Stotty 1356
gzhpcu (phil) 1029
...etc,

Any reason...or is it a glitch my end?

[John Yandell]

huh...yours went up but phil's did not... mine also stayed the same...will look into it...

[jimlosaltos]

Fed's Serve Variations

John,

This is undoubtedly covered somewhere in your fine series on Federer's and others' serves, but let me try and post this as a trio of questions.

1) Does Federer have a variation of service tosses and if so what are they? Your recent slow-mo video showing the very subtle wrist arm variations in his delivery is great, and each toss looked identical to me. But Fed has several different serves and I hear analysts such as Darren Cahill and Jimmy Arias say that Fed varies his toss. Cahill: "Fed has several service tosses". Arias, as Fed hit an ace up the T that left Djokovic flat footed during ATP WTC, "Fed hit a T serve out of a fake kick toss." That wording is identical to what I remember Jim Courier saying of his own serve.

We've recently seen "toss cluster" graphics as part of the stats that dribble out from HawkEye. Nadal's cluster is remarkably tight, with a higher toss on the second being the lone variation apparent. But I haven't yet seen that for Fed.

2) Comparing two vidcaps here, which I took from public slomo vid (240 fps) and annotated, what stands out to my naked eye is the much earlier shoulder rotation on the T serve vs kick, and lower impact point on the kick. Makes sense? Not? {Great examples of your "Hoppity Hop" drill, by the way <g> }

[IMG]
FedServeKickVsSlice by james.fawcette, on Flickr[/IMG]

3) Fed's landing point seems to vary widely in my photos from match play at BNP IW. Is that the by-product of his shoulder rotation or impact point or what?

[IMG]
FedServeLandingPointstennis by james.fawcette, on Flickr[/IMG]

Thank you!

[jimlosaltos]

Metrics

Not a question, but an affirmation of the value in the type of concrete quantified insights Tennisplayer.net provides, via another sport.

From Wired;

"How Science Turned a Struggling Pro Skier Into an Olympic Medal Contender"

http://www.wired.com/wiredscience/2014/02/ski-run-nyman-sochi-olympics/?cid=co18291974?mbid=nl_wired_02112014

"unlike many other athletic maneuvers, perfected through thousands of attempts against fluid, ever-changing opponents, Nyman developed his tuck with data, the mathematical truths of aerodynamic physics.

.... A monitor at your feet spits out real-time data, quantifying the aerodynamic drag and localizing its sources on your body. “Steven is a wind tunnel freak,” says Troy Flanagan, director of high performance for the US Ski Team. “You’ve got to be super strong, and he’s a big dude” — 6-foot-4, 212 pounds — “so he gets a lot of force on him, but he holds really still the whole time.” Flanagan, who has a PhD in aerospace engineering, is the primary driver of the team’s adoption of science-based training and assessment. He knows the approach works—he helped turn his native Australia’s underperforming Olympic teams into perennial contenders."

[stotty]

Roger Wilco

This is my absolute favorite of your music videos, well at least so far........slow classical violin music seems also to really complement super slow motion of Roger's on court movement. Many thanks.

[John Yandell]

Jim,

The answer is I don't know. When Fed lands further in I suspect the toss was more forward and he is chasing it to achieve the same contact point. So far as I can see from the video the relationships between his body his racket and the ball are very very similar.

[John Yandell]

Licensed Coach,

Thanks for the great words and maybe I will try some violin music next. We have an LTA Coach who has been posting under the organization login they give you guys for a long time and is a fabulous asset.

For the sake of clarity could I give you a personal login? I would love to have more LTA guys making regular posts. Email me ok: videotennis@metricmail.com

John Yandell

[gzhpcu]

Hi John, I started a thread on "Biomechanical Characteristics". Care to comment? I find the concept interesting and wonder if you know of anyone using it. Thanks

[jimlosaltos]

thx

Jim,

The answer is I don't know. When Fed lands further in I suspect the toss was more forward and he is chasing it to achieve the same contact point. So far as I can see from the video the relationships between his body his racket and the ball are very very similar.

Thanks anyway. I'll keep hunting. best / j

[John Yandell]

Phil responded per request!

[jimlosaltos]

Genesis Pull-Flip-Roll?

John,

Thinking about your great Vid with Rick Macci on modern ATP forehand, I wondered who first put those pieces together in this fashion? Does it pre-date Federer?

I remember Jimmy Arias being credited with innovation of the open-stance, topspin forehand (or his engineer father) at Bolleteri. And "wind-shield wiper" predated this, but what is the genesis? Who is the "Father of the Modern ATP Forehand"?

One of my pics, for fun:
[IMG]
Federer Forehand Extension Tight Qtr BNP ATP tennis 936 by james.fawcette, on Flickr[/IMG]

[John Yandell]

Great Pic and again the answer is I don't know. I think the flaw is the assumption that there was a "father."

[stotty]

John,

Strange how these "post numbers" keep locking on a certain number. Yesterday I was up to 1400 and something...now I've dropped back and locked onto 1368. It's no big deal, just thought I'd let you know it still/keeps happening.

[jimlosaltos]

Luke, I ...

Great Pic and again the answer is I don't know. I think the flaw is the assumption that there was a "father."

You're probably right, John, but sometimes it is important to know one's lineage Thanks.

[John Yandell]

Stotty, Thanks and as you probably gathered it hasn't made it to the top of the list.