Hitting up vs. Brushing up on the serve

Discussion in 'Tennis Tips/Instruction' started by HunterST, Jan 29, 2013.

  1. HunterST

    HunterST Hall of Fame

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    "Make sure you hit up on the ball." It's an extremely common piece of advice on the serve, but it's a bit unclear. I always took it to mean brushing up the back of the ball with a closed racket face (perpendicular to the ground).

    While learning how to serve a volleyball, I began to wonder if I misinterpreted. To serve a volleyball overhand, you have to, very litterally, hit up. That means the hand would be angled upward on contact.

    Considering this, I wondered if players should be "hitting up" in this manner on a tennis serve as well.

    I tried it out and had some mixed results. My 1st serve seemed to benefit. It got a little more powerful and went in with pretty good consistency. Topspin serve got less consistent though. I'm not sure where I stand on this issue.

    Thoughts on this?
     
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  2. LeeD

    LeeD Bionic Poster

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    Well, topspin second serves, for sure, you gotta hit upwards so the ball clears the net. If you hit straight out level with the ground, the topspin brings the ball down below net level.
    For flat serves, you don't need to clear the net by more than 10", so while your ball CAN leave your racket dead level with the ground, a racket moving upwards with a SLIGHTLY closed face can give you a deadball effect, like a knuckle ball, so the ball arcs downwards, but you hit a flat fast serve.
    That is an advanced technique. If you do the math, your strikepoint maybe mid 9' above the net, you cannot "SEE" the service court, and neither can the ball. You need to impart some curve to the ball, but not topspin, as that slows down the speed of the ball.
     
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  3. greystar403

    greystar403 Rookie

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    I point the racquet face SLIGHTLY SLIGHTLY upward because the ball stays on the racquet a tiny bit longer, which results in more spin. You also get a slight height boost.

    The results aren't very noticable. I guess for me it's more in my head.
     
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  4. HunterST

    HunterST Hall of Fame

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    Anyone else care to weigh in? Now that I think about it, if the racquet face isn't open, the ball can't go up.
     
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  5. charliefedererer

    charliefedererer Legend

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    "Up the Mountain" excerpt form Serve Doctor presents: M.P.H. http://www.youtube.com/watch?v=WlPVdppfYGs

    The basic idea is many players feel the main direction of energy direction is forward, like when a pitcher throws a fastball to a catcher.

    But Pat Dougherty, the Bollettieri Camp "serve doctor", explains serving is more like throwing a ball straight up into the air.


    Here's a picture of Sampras ready to launch "up the mountain" out of his incredibly aggressive trophy position:

    [​IMG]


    Here is a series of photos of his serve, illustrating not just his body, but his arm and racquet are directed almost straight up.

    [​IMG]

    I think the upward body launch is just pretty apparent.

    But notice how low he drops his upside down racquet in pic 4.

    He then pulls the butt of the racquet almost straight up in pics 5 before the elbow just starts to straighten out in pic 6 initiating the racquet "flip" from upside down to right side up, and the last second pronation movement seen in pic 7.

    Keeping a relaxed wrist and throwing the butt of the racquet up at the ball can't help but flip the racquet, and if you got the racquet well out to the right side of the body, resulting in pronation.

    The signature pose in pic 10 with the elbow high and the racquet straight down is from not resisting that flip and pronation until the movement is complete.

    THAT is "hitting up the mountain".



    Of course in a second "topspin" or "kick" serve, the ball is struck at a lower point, and the ball does get "brushed up", as can be seen below:

    [​IMG]

    Notice the ball is indeed rising after it leaves the racquet, as the ball is well below the top of the "24" in pic 24, and equal to the top of the "27" in pic 27.

    The stop action in this photo sequence allows us to see how extension at the elbow maintains the "hit the ball with the butt of the racquet" aim until at least pic 7.
    Then like Pete above, but in more detail here, you can see how a loose arm and wrist allows the racquet to flip to right side up, and to pronate from left to right - getting that a nice "slap" on the ball in addition to the "brushing up" quality.
     
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  6. luvforty

    luvforty Banned

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    charlie - I call you the serve surgeon !
     
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  7. Dimcorner

    Dimcorner Professional

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    Count me in as a converted up the hill hitter! I thought I was going to end up launching the ball to the next court (I did a few balls) but after figuring out timing and small adjustments to wrist angle I'm getting the hang of it. I can swing almost at full speed, not crack my shin, and my hitting partner says they are landing in more often with more spin AND speed (than my old 50% speed 2nd serve swings)
     
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  8. luvforty

    luvforty Banned

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    the other way to describe this -

    since the swing is a circular motion, not linear, so the initial acceleration direction is not the impact direction.

    think about hammering a nail into a wall, you do accelerate UP initially.....

    but you accelerate forward only if you hammer one into the floor :)
     
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  9. fuzz nation

    fuzz nation Legend

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    Even the tip of trying to "hit up on the ball" isn't universal. I might say that to a player who was bending at the waist too much and effectively pulling down through their serves. One of my kids hits her serves with a lot of spin though, since she already knows how to hit "up on the ball" just fine. I'm actually trying to coax her to hit a little more "through the ball" so she can generate some pace when she needs it.

    The tip or the image that a teacher uses to promote one action or another is almost completely dependent on what that player is already doing if that guidance is actually going to be constructive. This might be my round-about way of saying that you're probably hitting up on the ball just fine.

    Also keep in mind that there are significant differences between serving a tennis ball over a 36"-40" net and serving a volleyball over a net that's... hmm... well, it's sure higher than six feet! The volleyball has to get up over that high net from the top of our reach, but the tennis ball has to get down over that much lower net starting from a point well over a foot higher than the top of our reach (remember that a standard racquet is 27"). While that volleyball physically requires a little upward drive to clear that net, not so much at all in the case of the tennis serve.

    What is sort of interesting to me is that the volleyball serve doesn't benefit from the extra mechanical element that we get in a tennis setting when wielding a racquet (the racquet head can fly faster than a v-ball server's hand). I'd say that this makes the volleyball serve a very good illustration of how much power can be derived from the legs and core for that general motion. Guess I've gotta tune in on some volleyball coverage now...
     
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  10. HunterST

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    Yeah, that upward drive that is demanded for a volleyball serve is what got me thinking about what "hitting up meant." Obviously it would be way more exaggerated in a vb serve than in tennis, but I wondered if that was what hitting up was.
     
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  11. Chas Tennis

    Chas Tennis Hall of Fame

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    Phrases such as 'hit up the mountain' or any other words to describe the very complex 3D body movements in a serve require clarification from those who use them. How can a few words describe a complex 3 D motion?

    'brushing up the back of the ball'
    'hitting from 7 to 1 o'clock' on a kick serve

    How many of these terms have a positive value that outweighs their possibly misleading interpretations?

    For example
    https://vimeo.com/40449544
    Maybe ?? Stosur is 'brushing up the back of the ball' with a '7 to 1' direction, very fast, at 240fps it's difficult to see. But you can see that the racket is also definitely rotating very rapidly at impact. I've heard 'hit 1 to 7' many times but the more complex racket rotation has never been part of the description. 'Brushing' seems to me a different motion conceptually than this rapid rotation (I think that this interpretation of brushing is screwing up my kick serve improvements.). If you brush up 1 to 7 and don't have the racket rotation is your kick serve forever doomed? (Yes, we all know our serves are likely doomed forever anyhow......)

    In this video, what part of the motion of this serve is ’up the mountain’? What is the clear and useful interpretation of the term?
    https://vimeo.com/53440915
    I believe that his hand stays mostly level for some time before and after impact.

    Also, while the less important components of the serve that can be observed by eye get a lot of attention and discussions the most important part of the serve that can only be seen in high speed videos receives hardly any discussion. A completely muddling and misleading term "pronation" is most often used instead of internal shoulder rotation (upper arm axial rotation). Is there a single instructional video where the term internal shoulder rotation is used?

    https://vimeo.com/27528701

    Where is the up the mountain, brush the ball, hit 1 to 7, etc . What stands out is the very high racket head speed created by the rotation of the upper arm.

    If you have some short phrases for describing components of the service motion, please reply with the term, its meaning and possibly find a high speed video to show how term applies?

    BTW in the OP - "with a closed racket face (perpendicular to the ground)". A Closed racket means that the highest edge of the racket, as held, is forward, closer to the opposite court. A closed racket tends to hit the ball more downward than a neutral or open face. The racket might feel closed at impact on the serve but you can’t tell unless you check with high speed video. In the videos of pros the racket face seems close to neutral (not open or closed). PS - Players often hit overheads into the net because they are positioned a little too far away from the falling ball and therefore reach and contact it with a closed racket face. If the toss on the serve is too far in front the same thing might happen.
     
    Last edited: Jan 30, 2013
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  12. LeeD

    LeeD Bionic Poster

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    "up the mountain" is NOT straight up, but about 30 degrees upward, like a long throw....baseball or football
     
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  13. toly

    toly Hall of Fame

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    Federer 2nd Serve Ball's Trajectory

    It seems that Federer hits the ball slightly downward with tilted forward racquet face.

    [​IMG]

    There is original video http://youtu.be/0ic0NN_VJzw :)
     
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  14. Chas Tennis

    Chas Tennis Hall of Fame

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    That Federer serve is just one shot. Maybe it was a fault.

    The question needs stats on successful serves.

    Racket Head Motion During Impact - Also, given the racket motion, the time that the ball is in contact with the strings, say, 0.005 sec, is not necessarily negligible regarding the racket velocity. IRS, for example, takes only about 0.03 sec for the racket to be edge-on at about 90° to the forearm to β at impact. Tilt during contact?

    How much is the racket tilting (closing) during those 0.005 seconds of ball contact? When during that time was the video frame captured?
     
    Last edited: Jan 30, 2013
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  15. sureshs

    sureshs Bionic Poster

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    Many first serves are aimed ever so slightly down when they come off the strings. That small deviation is critical to bringing down the ball into the box, because air drag, gravity and spin all together are still not enough, for that kind of swing speed.
     
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  16. LeeD

    LeeD Bionic Poster

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    I think that hitting slightly down thing might work for the pros who hit 130+ serves, but for duffers like me, hitting barely 100, we need to hit slightly upwards, since our ball curves downwards much more due to slow speed, air drag, gravity, and wandering target and strikepoints.
    Regardless, what IS important is to finish our service swing stroke AS we are hitting the ball, and definetely NOT after hitting the ball, which is seen in most vids of us guys trying to show off our serves.
     
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  17. toly

    toly Hall of Fame

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    I have no idea.

    There is racquet motion around impact where video speed is 500fps. IMO contact point is in Frame9.

    [​IMG]

    See also some examples in thread http://tt.tennis-warehouse.com/showthread.php?t=440128
     
    #17
  18. user92626

    user92626 Legend

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    I pretty much understand and visualize serving the serve as Federer does. That is hitting down with a slightly close racket face, but because the racket head is on the upward/forward swingpath, the ball goes forward with power and some spin. :)

    That's just how the racket contacts the ball for the service motion. The real challenge lies in how to accelerate the racket, ie power.
     
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  19. Chas Tennis

    Chas Tennis Hall of Fame

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    Toly, Interesting definitely is a closed face before, during and after impact.

    Maybe that is a slice or kick.

    Looks different than this serve. Maybe this is a flat serve. ?
    https://vimeo.com/53440915

    I thought that Stosur's kick serve looked closed racket at impact but from behind it was not possible to be sure.

    What are the angles on the racket face for each type of serve at impact?
     
    #19
  20. sureshs

    sureshs Bionic Poster

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    Can you elaborate on that?
     
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  21. sureshs

    sureshs Bionic Poster

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    It is nice to see my ideas now being accepted universally. I was banned for fighting about this one.
     
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  22. LeeD

    LeeD Bionic Poster

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    You see all those vids of 3.0 thru 5.0 players using a very short pre contact swing, and a long full followthru that brings the rackethand all the way down to the thigh.
    High hand at beginning, low hand at finish.
    Wrong.
     
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  23. bhupaes

    bhupaes Professional

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    Chas, note that even though the racquet face is closed (in the Federer serve sequence), the racquet head is rising. The ball trajectory will be downward due to the closed face, and top/side spin will be imparted since the strings are rising as contact is made. The same is true for the video you have posted, but it looks like a flat serve, so the racquet face is not closed and the fact that it is rising at contact is harder to see. IMO, as always.
     
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  24. LeeD

    LeeD Bionic Poster

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    That's the deadball serve I'm always preaching we should aim for.
    Rackethead moving still upwards.
    At moment of impact, racketFACE slightly downwards.
    Like a knuckleball in baseball, the barely spinning ball drops faster than a flat hit ball, while maintaining the speed of a flat hit ball, for first serves.
     
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  25. sureshs

    sureshs Bionic Poster

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    Oh no bhupaes please don't. Don't make me say it again that if one part of a racket is moving, every part is moving, whatever twisted angle it might be, and nothing it touches can be hit down. Closed face moving upwards still cannot hit anything down. No, please I have gone through this before. I cannot take it any more.
     
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  26. LeeD

    LeeD Bionic Poster

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    Closed face moving upwards definitely CAN hit the ball downwards, but not perpendicular to the racketface.
    Close your racketface to 45 degrees on a forehand. Swing at the ball slightly upwards at maybe 7 degrees upwards of horizontal.
    The ball goes DOWNWARDS of the closed racketface, even though the swing is upwards.
     
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  27. luvforty

    luvforty Banned

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    Lee you wrong on this one... Sampras' 1st serve, 2700 rpm ish?

    dead ball doesn't drop faster, it may accidentally knuckle ball down, but it's not predictable..... that's why catcher needs extra large glove to catch Tim Wakefield.

    aerodynamically you cannot make it drop faster than a topspin ball, consistantly.
     
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  28. bhupaes

    bhupaes Professional

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    Sureshs, you need to grow up... tenniswise, that is. :)

    Seriously, I leave it to you. Believe it or not, it is possible and we all do it when we serve.
     
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  29. boramiNYC

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    suresh I think you are right. esp for 1st serve the contact is at the highest point of the arc the racquet head makes and at that point the face is little closed.

    I think on second serve the face could be even more closed but the head could be rising slightly just before it reaches the apex of the arc.
     
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  30. LeeD

    LeeD Bionic Poster

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    Your thinking is askewed.
    Nobody, including ME, has ever preached to hit a dead flat ball over a topspin serve, if you want it to go in most of the time.
    And nobody ever claimed a topspin serve can go nearly as fast as a flat hit ball.
    Sampras RPM slow down his fastest serves, which explains why his fastest only go around 137, while Roddick and Milos exceed 150.
    And when did anyone claim a dead ball serve can drop faster than a topspin ball?
    You know I hit topspin second serves. If I claimed as you say I did, wouldn't I be hitting deadball second serves?
    But I don't, I hit a topspin second serve so the ball SLOWS DOWN, and the spin helps gravity arc the ball into the court with high net clearance.
    Please don't inject your own ideas about what I say. Instead, just read and understand what I say as is.
     
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  31. LeeD

    LeeD Bionic Poster

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    Oh, I was addressing Luvforty, who somehow thinks I preach a deadball serve over a topspin serve for second serves.
    For flat first serves, a deadball serve goes in more often than a pure flat.
     
    #31
  32. luvforty

    luvforty Banned

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    never mind, let's call the whole thing off lol
     
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  33. boramiNYC

    boramiNYC Hall of Fame

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    oops maybe I misunderstood..
     
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  34. sureshs

    sureshs Bionic Poster

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    What is the fun in growing up?

    If you are referring to the string deformation, I agree with you. I have said that it often appears that the player has caught the ball on the way up, just below the apex. So he is hitting up. However, the ball exits very slightly down when the racket comes over the apex. That is the role of the dwell time. The closed face is not the one that directly produces the effect - it is the deformability of the strings.

    I know what you are thinking. Hold the racket face slightly closed and move it up over the ball. Looks like that is what is happening, right? No. In the serves we are discussing, the ball leaves the strings when the racket has just started descending from its apex after the dwell time.

    If you don't believe me, ask anybody who knows his stuff. Ask them whether any part of a rigid body can be moving down when another part if moving up. Also ask him if it is possible for a body to impart a force opposite to the direction of its motion.

    Pros (and even club players) how often time their serves well enough that this happens quite frequently.

    And of course there are many serves in which the ball is actually hit up and rises after impact.
     
    #34
  35. sureshs

    sureshs Bionic Poster

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    Oh there is one case in which hitting up on the ball can cause it to go down. That is when you hit it so so so so so softly that it cannot even overcome gravity instantaneously. We had discussed this also long ago.
     
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  36. Relinquis

    Relinquis Hall of Fame

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    sureshs,

    isn't it moving forward as well as up? wouldn't a closed face racquet moving forward impart some downwards force?

    i don't have an engineering or physics background.
     
    #36
  37. sureshs

    sureshs Bionic Poster

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    Is there a particular situation you are referring to? There are many many cases in which the racket is moving forward and up, and hitting up on the ball. There is no debate there.

    This is a very subtle topic, so we must be very precise here. The deformation during dwell time really comes into the picture in the cases which are discussed.

    To be very literal about your question, a racket moving forward would impart a forward force. It could be open, closed, twisted, upside down whatever. It will still exert a forward force.
     
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  38. LeeD

    LeeD Bionic Poster

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    Post 26, but that is a groundstroke example.
     
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  39. toly

    toly Hall of Fame

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    Let’s analyze Rionic serve.

    [​IMG]

    Because of low video speed it is impossible to define point of contact. From Frame1 to Frame2 the racquet is rising. From Frame2 to Fram4 the racquet is falling.

    Next picture shows ball’s trajectory.

    [​IMG]

    The ball flies downward. So I think contact occurs between Frame2 and Frame3 with slightly closed racquet. It seems Rionic hits flat serve without topspin.
     
    Last edited: Jan 31, 2013
    #39
  40. sureshs

    sureshs Bionic Poster

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    Notice how the racket tip is moving up just before contact and then moving down through contact. That is missed by many people who only see the first.

    And see how the ball leaves slightly below horizontal.
     
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  41. charliefedererer

    charliefedererer Legend

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    ^^^ Toly, as always, you have the best pics to prove a point.

    [When serving, I sure do wish I was 6'5" and had Raonic's motion/strength so I could hit the ball the down on my first serve.
    I'd even settle for Fed's motion/strength.]
     
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  42. sureshs

    sureshs Bionic Poster

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    Let me point something out at once before somebody jumps on the last single photo of Raonic.

    Don't tell me that the racket is pointing upwards while the ball is coming down, so I am wrong.

    Just don't tell me that.

    We have been over this before. The upward bent shape of the frame at the top is a camera effect due to the sequence in which the image is captured. We had a photography expert explain it on this forum.
     
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  43. charliefedererer

    charliefedererer Legend

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    No one can consciously control what is happening in the thousandths of a second between when the racket goes from moving up just before contact and contact.

    The best we can do is set it up by hitting up at the ball, and letting the racquet finally pass through the apex of the arc.

    At some point, one milimeter/millisecond before the racquet was going "up", and the next "down".
    The important motion is the continued sweep of the arm/racquet through contact without regard to "up" or "down".

    But if we hadn't set it all up by hitting up, we wouldn't be getting the force needed on a well executed serve.
     
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  44. sureshs

    sureshs Bionic Poster

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    ^^^ Correct.

    That is the way to approach it, as a teaching metaphor, instead of claiming that it actually happens that way.

    BTW, after having looked at many, many such photos, I think pros do have the ability to catch the ball around the apex of their swing. If they did not, the ball would fly out if they swung so hard at it from below (spin, gravity, not withstanding).
     
    #44
  45. toly

    toly Hall of Fame

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    Rionic hits the ball with slightly bend elbow that allows him to restrict wrist ulnar deviation that’s why racquet during impact moves downward. So, some motions we can control and create them knowingly. We just must exactly know what we supposed to do at any particular moment of the racquet swing.
     
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  46. bhupaes

    bhupaes Professional

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    Looks to me like Frame 3 is post contact. I posit that at contact, the strings were moving upwards. Between Frames 2 and 3, the hand has moved forwards and slightly down. Due to upper arm rotation, the racquet which is moving in an arc from left to right (of Raonic) is still straightening out and gaining height. The resolution here is not good enough to say whether the net gain is upwards or downwards.

    But regardless, I believe one can say with certainty that if the ball has any amount of topspin, the only way that could have happened is if the strings were moving upwards through contact. And surely Raonic's first serve has a decent amount of topspin.
     
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  47. Chas Tennis

    Chas Tennis Hall of Fame

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    Reference the ball position by the guy in the white T-shirt in the stands behind Rionic. On frame 1 & 2 the ball is falling and lines up with his arm. On frame 3 the ball has considerably moved forward. The ball impact was after the exposure of frame 2 and before the exposure of frame 3, as bhpaes said.
     
    Last edited: Jan 31, 2013
    #47
  48. toly

    toly Hall of Fame

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    Yes, thank you. I corrected my post.:(
     
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  49. sureshs

    sureshs Bionic Poster

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    Look at the position of the ball wrt the top white railing. It is constantly falling. First, it was following due to gravity, and it is still falling post impact.

    If it is falling, it could not have been hit up with that high of a swing speed, gravity notwithstanding.

    If the ball was hit up, we would have seen at least a momentary increase in height. We see only decrease.

    The spin in explained by the action over the dwell time. The ball is caught just below the apex by the strings, and the friction during the upward movement of the strings is the one that creates top or side spin. When the ball is released, it comes off with the spin on it, but slightly downwards, as the frame has moved over the apex.

    That is how these serves are hit. Not taking the dwell time at the apex into account results in paradoxes like how come the ball has top spin but is moving down after impact, etc.

    It is not simple by any means.
     
    Last edited: Jan 31, 2013
    #49
  50. toly

    toly Hall of Fame

    Joined:
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    The racquet and strings aren’t moving upward between frames 2 and 3, right? Thus, there cannot be “decent amount of topspin” unless strings significantly slide downward and then back to original position during impact. :confused:
     
    #50

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