Poll - % Pros Looking at Ball Impact for Serve?

Discussion in 'Tennis Tips/Instruction' started by Chas Tennis, Oct 12, 2012.

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What % of pro are looking at the ball at impact on the serve?

Poll closed Nov 11, 2012.
  1. Between 97-100%

    2 vote(s)
    22.2%
  2. Between 90-97%

    1 vote(s)
    11.1%
  3. Between 75-90%

    0 vote(s)
    0.0%
  4. Between 50-75%

    1 vote(s)
    11.1%
  5. Less than 50%

    5 vote(s)
    55.6%
  1. Chas Tennis

    Chas Tennis Hall of Fame

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    % Pros Looking at Ball Impact for Serve?

    On the serve - overall, what percent of pros are looking at the ball when it is impacted by the racket?

    All pros, all types of serves.

    This is best observed from the side (viewing along the baseline) in high speed videos?
     
    Last edited: Oct 12, 2012
    #1
  2. LeeD

    LeeD Bionic Poster

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    Without watching a series of videos, I'd reckon less than half, are still watching the ball at the moment of impact.
     
    #2
  3. user92626

    user92626 Legend

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    I'll let other pros answer your survey. But Goats and hall of famers like LeeD and me don't look at the ball at all.

    Looking at the ball is for losers.
     
    #3
  4. LeeD

    LeeD Bionic Poster

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    In my defense..:):)
    I"m Asian, have slanty eyes that see side to side great, but not upwards or downwards.
    I've worn a hat for tennis since 1989.
    My neck is stiff from 25 years of 5 day a week surfing on shortboards.
    I've been serving a tennis ball since 1974.
    Would you believe that I tossed it up every time? Myself.
    I haven't caught any of my tosses since maybe 1976.
    Where can my ball go, really?
     
    #4
  5. sureshs

    sureshs Bionic Poster

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    What about if you also move your head up or down?
     
    #5
  6. user92626

    user92626 Legend

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    His asian neck would break. Only red necks could move like that.
     
    #6
  7. LeeD

    LeeD Bionic Poster

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    I have surfer's neck, from 3 years of competing 4A, 4 years to get there, and 20 years of free surfing after that. Nobody of my generation in surfing can look upwards by craning their neck. We all arch our backs like a twist serve.
    I can bend over, turn more than sideways, and stare straight up at the sky, but that is not the best position for a high strikepoint on serves. It's a Yoga pose, though.
    Would you believe I haven't been able to raise both hands over my head at the same time in over 6 years? Rotator cuffs destroyed, from motocross crashes to overuse throwing rocks and sand dollars in my youth. I can do it if you assist by lifting my elbows..:?
     
    #7
  8. Chas Tennis

    Chas Tennis Hall of Fame

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    Are the pros looking at the ball when they hit it on the serve? Are you?

    Last call to vote in the poll. (The identity of the voter is not recorded in the poll.)

    I have looked over a small sample of videos. While the videos are not ideal I did estimate some stats. Will post in a few days.
     
    #8
  9. Chas Tennis

    Chas Tennis Hall of Fame

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    Some Observations- % Pros Looking at Ball Impact on Serve

    High speed video may be required and was used here. ? To view whether the server is looking at the ball a side view along the base line works well. It would have been better to view from the face side along the baseline. Front and back views do not work as well in my opinion. The front view is especially deceptive because the eyes are up but you cannot tell where they are looking. Since I could not always see the face I judged either by the head angle (mostly) or by the face profile(sometimes) whether the server was looking at the ball at impact or not. There is still some uncertainty because in the majority of videos the eyes could possibly have been at an extreme angle toward the ball.

    The serves - no information on which kind of serve or whether the serve was in.

    Results - 60 videos total -

    The male servers in this sample were never observed to be looking at the ball at impact on the serve.

    While we have to confirm this observation elsewhere it certainly has changed one on my solid beliefs about watching the ball at impact on the serve................

    Sample video with face in profile
    https://vimeo.com/53440915
    Stop action on Vimeo - press play-pause button as fast as possible, not perfect. Better if you can download MP file and view on Quicktime, stop and use QT forward & backward arrows for single frame stop action.

    Anyone have data on this issue?
     
    Last edited: Nov 13, 2012
    #9
  10. boramiNYC

    boramiNYC Hall of Fame

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    It's related to the posture that you can see from olympic weightlifters. When the weight is supported above the head you must look squarely front. If they look up the same weight cannot be supported. At full extension for impact during serve unless the head is already turned toward the target the extended arm loses its ability to achieve high swingspeed at full extension. This is different from rotational swing of GS where it's possible (but not a requirement) to fix the eyes for the ball at contact.
     
    #10
  11. Chas Tennis

    Chas Tennis Hall of Fame

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    Tennis serve - camera view from above.

    Fuzzy Yellow Balls has some high speed videos on Youtube where the camera views the server from above. You can get a good look at how well the server's eyes are on the ball at impact.

    http://www.youtube.com/watch?v=G1a7Qq0eljU

    I looked at this video for the flat serve and another for the kick serve and the servers did not appear to be looking at the ball at the time of impact.

    It would be interesting to find some ATP & WTA servers with the same camera viewpoint from above.
     
    #11
  12. the hack

    the hack New User

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    great video Chas. thanks
     
    #12
  13. toly

    toly Hall of Fame

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    Stosur Serve Top View

    http://youtu.be/wG-Lc-bO4a8
     
    #13
  14. Cheetah

    Cheetah Hall of Fame

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    you actually get greater swing speed if you dont look at the ball at contact.
     
    #14
  15. SystemicAnomaly

    SystemicAnomaly G.O.A.T.

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    This certainly appeared to be the case for Roddick. His eyes appear to be on the ball when his arm reaches full extension (racket in the "big L" position). however he quickly pulls his eyes/head down so that at contact he appears to be looking at the receiver.

    Contrast this with Sampras and Federer. These guys keep their eyes on the ball longer/later. From the slow-mo videos that I've seen of these two, their eyes appear to be on the ball pretty close to contact. From repeated viewing of a number of videos, it is conceivable that their eyes might be on the ball at contact but it is difficult to determine, with absolute certainty, if their eyes are really still on the ball.

    Because the hitting shoulder comes over the top (shoulder-over-shoulder cartwheel action), the head must move off to the side a bit. The head and neck also rotates somewhat to accommodate the shoulder. However, it does appear that Roger and Pete still watch the ball out of the corner of their eyes even tho' the head had moved/rotated.

    Bottem line: I would say that Roger & Pete might very well be looking at the ball at contact. Even if this is not so, it is apparent that their eyes are still on the ball very close to contact unlike Andy (Roddick) and others.

    http://www.youtube.com/watch?v=vcjZ5r_YHV0
    http://www.youtube.com/watch?v=KqRqdbBEzUM
     
    #15
  16. christo

    christo Hall of Fame

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    Interesting observation! I'd like to see Cahill and Brad chip in on this topic as both are astute students of the game.
     
    #16
  17. Raul_SJ

    Raul_SJ Professional

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    #17
  18. Cheetah

    Cheetah Hall of Fame

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    i've heard at least 2 coaches say that you would get greater rhs on the serve if you tilt your head down just before contact because of the relationship of the neck muscles and the cartwheel action and this gives more flexibility at the end of the stroke. ... or something along those lines. I believe Heath Waters was one of the people that said that.
     
    #18
  19. Chas Tennis

    Chas Tennis Hall of Fame

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    From Reply #56
    http://tt.tennis-warehouse.com/showthread.php?p=7069659#post7069659

    This Stosur serve is during a match and shows the moment of ball contact. Probably a kick serve.
     
    Last edited: Jan 7, 2013
    #19
  20. SystemicAnomaly

    SystemicAnomaly G.O.A.T.

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    #20
  21. lendl1986

    lendl1986 Rookie

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    Seems your neck would get stressed looking upward while your body's weight is going forward at ball contact.
     
    #21
  22. Chas Tennis

    Chas Tennis Hall of Fame

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    Serve from Murray, Federer & Viadisova - side views.

    See
    Murray - 1:09
    Federer - 1:56
    Viadisova - 2:27

    http://www.youtube.com/watch?NR=1&v=tCKWHe3oIx8&feature=endscreen

    The other servers shown on this video are unclear or the impact in not shown.

    Maybe trying to watch the ball stresses the neck and/or reduces pace on the serve as some replies have indicated.

    I'm dropping looking at impact as a goal for my serve unless I find other information supporting it.
     
    #22
  23. SystemicAnomaly

    SystemicAnomaly G.O.A.T.

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    ^ I believe that you are coming away from this with an erroneous notion of what is going on with these serves. Murray, Federer, Vaidisova, Sharpova and many other servers are still looking at the ball very close to contact. They are obviously watching the ball at the trophy phase and are still watching as the tossing arm drops and as the racket head drops. Even at the "big L" (when the racket arm becomes fully extended), most of these servers still have their eyes trained on the ball -- even tho' the head has started to move/turn.

    Even Roddick appears to be looking at the ball at the "big L". However, his head quickly turns and looks forward from this point. Not so for the other servers mentioned above. Note that the time it takes to move the racket head from the "big L" up to the contact point is very short -- it would be measured in milliseconds or centiseconds. For this reason alone, I maintain that most servers are fixated on the ball very close to contact.

    Furthermore... even when the head moves/turns, the eyes can still adjust their position so that the foveal (central) vision is still trained on the ball. It is not that difficult for the eyes to point in a direction that is 45 degrees offset from the primary direction of the head. So... even when they are not directly facing the ball, the eyes can still be looking at the ball.

    Bottom line: It is probably best for most of us to watch the ball as close to the contact as possible. I've seen plenty of players who pull the head down much too early -- before the "big L" -- or even before the racket starts it's upward swing. If you decide that it is not important to watch the ball to contact, you may end up pulling your head/eyes down much too early as a result.
     
    #23
  24. Chas Tennis

    Chas Tennis Hall of Fame

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    Very interesting points but this thread was more for just the one simple question - When serving, are the pros looking at ball impact?

    I had believed that for looking at the ball for both ground strokes and serves that I should apply exactly the same principle - keep your eye on the ball impact area before, at, and after impact. I still believe it for ground strokes but not now for serves.

    For my serving practice in the past I found that if I looked at ball impact and also kept my head & eyes still afterwards it usually resulted in a more accurate hit. But looking at the ball is my biggest tennis problem, who knows how I view the ball in my usual match serve.

    I noticed looking at pro serve high speed videos from miscellaneous viewpoints that often the servers did not appear to be looking at the ball at impact. Also, I know that if you do not have the correct camera view and do not look just at ball impact (or before) you can easily miss what is going on. So the question was first to get some stats on how often the pros are looking at the ball at impact.

    You mention breaking off at some point before impact earlier in the motion. Researching that point is very interesting and most important - what is really going on - but it is much more difficult to observe in videos. Can you find videos showing when pros break off looking? Or, if their eyes are still pointed up at an extreme angle when the head appears to be looking straight ahead? See eye test below.

    Since the body and arm are at an angle (when viewed from the side) and the racket is about vertical at impact I believe that the pros break off looking at the ball because their motion involves the upper body angling forward rapidly and it stresses the neck as mentioned in some replies. Perhaps for a club player such as myself the option to look at the ball through impact - as I have practiced for my serves - is possible because the rapid upper body motion is not being used. ? I'll have to compare my side view serves to pros to see the differences in motion and in body, arm and racket angles at impact.

    (The frames in reply #19 of JackB1 above show that his head is looking up and is very stationary, unlike Stosur's, but unfortunately the ball impact is not shown.)

    Some points for video analysis of this issue -
    1) no cherry picking as there are usually a handful of videos to show anything.
    2) high speed video, >200 fps.
    3) examine the frame showing ball contact (or before)
    4) side view, above view or some other view that clearly shows the head orientation at impact.
    5) there will be uncertainty as to where exactly the eyes are pointing - find some reasonable way to interpret the videos from head position. Do the eyebrows block the line from the eye to the ball impact? Is the server wearing a baseball cap with a blocking rim, etc.?

    Field of view eye test - Stand with the head looking straight ahead. Hold a tennis ball at arm's length above your head. Point the eyes up as much as possible but keep the head oriented straight ahead. Move the ball back and forth to determine where your field of view starts. When I do this and look at my arm angle, it is about 30° to the vertical. (It helps to have a mirror to the side to get the arm angle.) Because the eyes are set back from the eyebrows, the eyebrows limit the field of view upward. Probably can also search the eye's FOV on the internet.

    It would, of course, be better to find some tennis research using motion capture with high speed 3D cameras.
     
    Last edited: Jan 8, 2013
    #24
  25. corbind

    corbind Professional

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    I love threads like this with data and analysis. Looking forward to upcoming results.
     
    #25
  26. jakeytennis

    jakeytennis Rookie

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    i think its impossible to actually see the ball hit the strings, but that doesn't mean you shouldnt take your eyes off the ball any sooner.
    whenever i take my eyes off the ball, i frame the serve.

    the more you watch the ball, the more likely u will hit the ball on the sweetspot
     
    #26

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