How can I improve my serve?

Discussion in 'Tennis Tips/Instruction' started by hyogen, Oct 15, 2007.

  1. Ross K

    Ross K Legend

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    Just came across this older post, courtesy of In D Zone:

    Very very interesting indeed... NOW THIS WE HAVEN'T HEARD!... Do others also think she also takes back with r. hand and tosses ball with l. hand together at the same time? That could kind of fit in with my description (above) of the pronounced V shape her arms make etc?... Hmmm... could be a crucial aspect here?... if true, it sort of changes everything...
     
  2. Ghosting

    Ghosting New User

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  3. vince916

    vince916 Semi-Pro

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    You just started tennis after college so your around your mid to late 20s and you already have tennis elbow?
     
  4. hyogen

    hyogen Hall of Fame

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    who are you talking about? I started when I was about 11 or 12yrs old...

    i'm 25 now and have been battling tennis elbow since I was like 17 or 18.

    for the past 3 months almost now I have pretty much been tennis elbow free by using really flexy frames (less than 62ra stiffness)
     
  5. Ghosting

    Ghosting New User

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    My tennis hero Tim Henman says that tennis elbow is due to bad serve technique and I agree with him.
     
  6. sharpy

    sharpy Banned

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    I don't need a tennis hero to tell me that. Any decent player knows that. But it seems that the racket manufacturers are doing a good job making people think otherwise. Take the stiff frame that gave you tennis elbow, with that stiff string, and have roger federer play tennis with it. No tennis elbow.. What a surprise!
     
  7. Ross K

    Ross K Legend

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    tricky, everyone,

    Sorry if I was a bit unreasonable or unappreciative with last night's post. In my defence I'll say it's definitely not always easy to follow intense and technical debates on, in this case, serve motion mechanics. (And I'll be honest - I often have to read your posts a number of times before I hopefully grasp the meaning.) Plus there's nothing quite like a serve that's packed up and died on you during a match to p*** you off to the max!

    But just to recap. I actually feel the day has yielded 2 important things...

    1. In D Zone's comment on JH moving both hands/arms together suddenly seems somewhat crucial to me (and BTW, following my own ball toss, my takeback hand pauses a bit, it sort of lags behind and loiters around there!) Anyway, practising this today via shadow work - (the l. hand's toss action working simultaneous with the r. hand's straightarmed high takeback motion - result: V shape before racquet drop) - I think the things you've been saying are beginning to tie up. Also, having checked out some serve vids, I think a few other females have serve motions that are fundamentally the same as this... Sharapova certainly... Mauresmo too... (Is this a female thing here?)...

    I must say your words about throwing from the shoulder with an almost straight arm still perplex me (unless it is linked to your windmill exersize - but of course in a real serve you break the shape, you bend your arm to enable racquet drop...?!) This just doesn't make sense to me. But...

    2. Unless I'm mistaken, the diagonal takeback you refer to could be said to be simply due to the fact JH takes back with a pretty straight arm?... am I getting this right now?

    Anyhow, as I say, I think it's come together a bit more today... hands move together... r. hand is held very straight in takeback and ends up high and quite back before racquet drop (you're arms make V shape)... and (somehow... not quite sure how) you give it some shoulder on contact... voilla!...

    Please feel free to pass comment (or not as the case may very well be!)

    Ross
     
  8. tricky

    tricky Hall of Fame

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    The argument against going straight to frame is that people tend to go back into old habits about setting up the ball toss, trophy position, racquet drop, etc. But, yeah, you can just work with the frame too. That's fine.

    That's just something so that you get a feel for the shoulder. But it's not the actual motion itself.

    Shoulder-driven takebacks look simple, but they're more difficult to master because most people are not used to leading/rotating/pivoting around their shoulder. It makes more sense if you go through the progression, but again most people are used to taking it back with the elbow. Which again, won't make it look like Henin's serve. That is again why

    Yeah, the windmill was just to loosen up the shoulder. Once you're comfortable, then you work on setting up the trophy position by leading with the shoulder. Which is, again, not as easy as it looks. You can look at how Henin does it, and follow along.

    It's still a circular motion (i.e. a kind of C) -- your shoulder does not naturally move in any kind of straight line -- but to the eye, it'll look pretty straight. You can also visualize it as taking the back shoulder farther away from the front shoulder, feeling a stretch in the upper pec. Feeling the stretch in the upper pec lets you know you're really leading with the shoulder.

    Yeah, this is actually how most people (or at least the peoplearound me) are initially taught to serve. It gotten back into vogue due to Federer, and that's what sites like Fuzzy promote as well. It's simpler to time because it becomes more of one motion. You windup with the hips, and as you go back, both arms go up. As you said, it looks like you're forming a V -- you get better weight balance in your motion, and your trophy position is well ready before the ball reaches its height.

    I was describing the takeback itself. Her trophy position is a little odd in that the arm is not as bent as with most other servers. But, that again, is a sign that she's pivoting around the shoulder, rather than the elbow to set up the trophy position.

    Yeah, that's more or less what is happening. Again, it may be helpful just imaging yourself stretching your upper pec as you take the racquet back. That will help you get the "feel" down for what a shoulder-driven takeback should be. Also, work on taking the shoulder slightly behind your right hip as you take it back.
     
  9. tricky

    tricky Hall of Fame

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    The argument against going straight to frame is that people tend to go back into old habits about setting up the ball toss, trophy position, racquet drop, etc. But, yeah, you can just work with the frame too. That's fine.

    That's just something so that you get a feel for the shoulder. But it's not the actual motion itself.

    Shoulder-driven takebacks look simple, but they're more difficult to master because most people are not used to leading/rotating/pivoting around their shoulder. It makes more sense if you go through the progression, but again most people are used to taking it back with the elbow. Which again, won't make it look like Henin's serve. That is again why

    Yeah, the windmill was just to loosen up the shoulder. Once you're comfortable, then you work on setting up the trophy position by leading with the shoulder. Which is, again, not as easy as it looks. You can look at how Henin does it, and follow along.

    It's still a circular motion (i.e. a kind of C) -- your shoulder does not naturally move in any kind of straight line -- but to the eye, it'll look pretty straight. You can also visualize it as taking the back shoulder farther away from the front shoulder, feeling a stretch in the upper pec. Feeling the stretch in the upper pec lets you know you're really leading with the shoulder.

    Yeah, this is actually how most people (or at least the peoplearound me) are initially taught to serve. It gotten back into vogue due to Federer, and that's what sites like Fuzzy promote as well. It's simpler to time because it becomes more of one motion. You windup with the hips, and as you go back, both arms go up. As you said, it looks like you're forming a V -- you get better weight balance in your motion, and your trophy position is well ready before the ball reaches its height.

    I was describing the takeback itself. Her trophy position is a little odd in that the arm is not as bent as with most other servers. But, that again, is a sign that she's pivoting around the shoulder, rather than the elbow to set up the trophy position.

    Yeah, that's more or less what is happening. Again, it may be helpful just imaging yourself stretching your upper pec as you take the racquet back. That will help you get the "feel" down for what a shoulder-driven takeback should be. Also, work on taking the shoulder slightly behind your right hip as you take it back.

    It's, again, a more difficult motion to dial in. Roddick uses a smile-pattern takeback, which is a simpler motion, and it enables him to more easily take the racquet back with just the shoulder. To do it with the full circular motion, as you are trying right now, takes some work and extra visualization.
     
  10. HappyChappy

    HappyChappy Rookie

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    tricky:

    by ''lead with the shoulder'', do you mean: 'rotate about the shoulder'?
     
  11. hyogen

    hyogen Hall of Fame

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    Lol...is that you BeHappy? I have been wondering and posting in a couple forums why in the world were you banned?! D:
     
  12. tricky

    tricky Hall of Fame

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    Nice to see you back Happy. ;)

    Yup. Rotate around the shoulder is probably a better way to put it too. :)

    I think it's part of the board software to periodically ban the poor guy. :D
     
  13. sharpy

    sharpy Banned

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    jesus im really wondering why in the world gorilla, the dolphin, behappy keeps getting banned. what are you doing to get yourself banned? cursing out the mods in private pm? :D
     
  14. Ross K

    Ross K Legend

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    tricky,

    That ^ is such an awesome post!

    Somehow you've managed to steer a clear path through my sometimes half-realised or slightly confused take on your instruction vis a vis the Henin serve motion, and clearly explained several aspects that I wasn't quite 100 per cent with... and I was quite convinced you'd exited this thread for good? As I said before... "I'm not worthy!"


    Yesterday's experiment.

    Now, just to say, following my decision that I HAVE to change my relatively reliable, varied but WEAK serve, and following Saturday's unhappy experiences during a match (I suffered 'The Death of a 1000 Serves!'), yesterday I undertook some intensive serve work and experimentation whereby over the course of long day I attempted to familiarize myself with some different serve motions to see which might suit me a little more. So, keeping in mind that these were my self-taught, less than perfect interpretations of how I think these serves are accomplished, here are the different motions/styles attempted:

    1. Henin shoulder-centric semi-abbreviated style
    2. Traditional palm facing ground on takeback style
    3. A-Rod fully abbreviated shoulder-yank style (!)
    4. Nadal semi-abbreviated style

    Of the 4, it was the Henin motion and the Nadal motion that I seemed most suited to or got the most from. And of those 2, I think the Nadal style is the winner just for providing me with the beginnings of a real 'whipping', dynamic motion where I could really see some of the desired fundamentals occuring somewhat (great hip movement, a real twisting torso, an explosive drive through contact, etc.)

    So tricky, others, having thoroughly looked at the Henin motion, it is now the Nadal style I'd like to focus on in terms of basic mechanics and analysis (and btw, isn't Gasquet's also quite alike?) Anyway, minus his precise little movements with both feet (and doesn't he do a small back-foot drag too?), I feel I've kind of got his motion down, but would appreciate hearing some more informed opinions so as to be sure.

    Many thanks,

    Ross
     
  15. Ross K

    Ross K Legend

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  16. tricky

    tricky Hall of Fame

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    I think Nadal and Gasquet have a similar style serve. It's not especially powerful, but it (like Federer) is hard to read.

    So, first, the arm motion.

    Like Roddick, it's a "overhand" or upside down smile pattern motion. However, unlike Roddick, it's led with the elbow. So, first the arm motion -->

    The setup of arm motion:

    1) Start out with an Eastern BH grip. It's easier to learn this if you have a grip between continental and Eastern BH.

    2) With both hands, hold about chest level. Have your right arm be almost straight.

    Arm Takeback:

    3) Trace a slight curve or "sunrise" with the elbow. As you're doing this, pull your back shoulder away from the front shoulder. Again make sure the back shoulder is under the front shoulder.

    4) If you're doing this correctly, then you'll notice that you'll feel like you're going to fall backwards. If you're not getting this sensation, check your grip and use a stronger Eastern BH grip.

    5) Fire away in a forward motion. Keep practicing this until you feel comfortable.

    Sit and Lift:

    6) As before, set up your arms. Learn slightly forward.

    7) To initiate the takeback, start leaning backwards onto your butt and sit.

    8) As you continue the sitting motion, initiate the arm takeback, aim for the sky and toss the ball.

    9) When you've set up your trophy position, you'll be in a semi-squat position.

    10) To initiate the forward motion, explode upwards from your semi-squat. That is, lift upwards.

    Continue swinging. Once you've reasonably comfortable with this motion, then start moving grip toward a continental. Find the grip most comfortable with you.
     
  17. Ghosting

    Ghosting New User

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    I think the biggest mistake to hit a kick serve is just thinking about not get body forward. But if you see players with great kick, their body (chest) goes forward incredibly. Keeping left shoulder sideways to the net but taking the right shoulder up and really over left shoulder.

    http://www.hi-techtennis.com/serve/seesaw_example.php
     
  18. HEAD/PRINCE RULE

    HEAD/PRINCE RULE Rookie

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    wat is the trophy thing on serves???? ty
     
  19. Ross K

    Ross K Legend

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    tricky,

    Cheers v/much for the clear & concise Nadal serve breakdown - it helps so much!
     
  20. Ross K

    Ross K Legend

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    All-popular semi-abbreviated serve motion... too much arm...

    Was checking out the link (below) earlier to try and really study the Gasquet and Nadal motion. However, moving through all the vids, I was struck by how so many players seem to have such a similar semi-abbreviated motion - Nadal, Gasquet, A-Rod, Mauresmo, Henin and Ginepri - to name but six. (Okay, A-Rod's is a full abbreviated motion, but you know what I mean?) Anyway...

    Now, quite which particular one I should be examining, or which motion I most resemble (or, more accurately, would like to resemble) is another, slightly unclear matter of course. What I think might help generally though is a few tips to help end a persistant problem of mine... basically, I still feel I'm putting too much arm into the contact, as opposed to firing more from the shoulder, or pivoting and firing from the elbow... and BTW, I have noted some of tricky's correctives for this and tried to apply them, but I'm still sometimes getting the distinct impression - (like when you feel you've slapped the ball rather than driven right through it) - that the elbow and/or shoulder needs to get in on the act more.

    Anyone got anything to help get that, it would be great to hear it.

    Cheers,

    Ross

    BTW2, Here's that link:http://www.playerdevelopment.usta.com/home/default.sps Hopefully it will open. If you're not familiar with it, you should definiitely look through it as the vids and fh, bh and serve analyses are good quality.
     
  21. tricky

    tricky Hall of Fame

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    Yeah, I've been reviewing Brian Gordon's articles on service mechanics to kinda get down the body specifics of what is actually happening. Maybe work out a bunch of checklists for each aspect of serve.

     
  22. Ross K

    Ross K Legend

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    tricky,

    Cheers v/much. Have actually just been going through that ^. I obviously need to do a whole lot more, but it's great to isolate and patiently work on these componants like this then link them through.

    My only query:
    From how the whole piece reads to me, don't you mean it's actually for the Nadal/Gasquet motion? Henin of course goes both arms raised together overhead into the strong V position, whereas Gasquet/Nadal's overhand takeback (initiated incidentally with that characteristic twist of the wrist/racquet face so it appears flat and plate-like) is far less a vertical takeback per se (the top half of a circle shape or an upside down smile pattern)... or have I got it wrong?
     
  23. tricky

    tricky Hall of Fame

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    Yeah, the key thing is the windmill motion in step 2. This motion basically is to kinda get a feel for what "external rotation" is. The idea is that the closer you're able to track your takeback, racquet drop, and upward swing along how your shoulder rotates externally, then the more natural and more powerful the motion will be. However, this is difficult to nail down because the shoulder rotates in two planes. And so practicing this motion separately helps you isolate this before integrating this into a takeback.

    It's just a way to kinda get the "feel" down before you start practicing the takeback.

    If you practice a counterclockwise movement with your shoulder-pec, you're getting the feel down for a Henin-style delivery. That is, the traditional circular style but pivoting/rotating around the shoulder.

    If you practice a clockwise movement with your shoulder-pec or shoulder-elbow, you're getting the feel down for a Roddick (shoulder-pec) or Nadal/Gasquet-style (shoulder-elbow) delivery. That is, the upside down smile pattern. Obviously, the takeback is only a portion of this. If you want to do a more "correct" version, then trace just the top half of the windmill (clockwise), and then go back to the starting point.

    In both situations, you want to practice the motion with the racquet face toward the ground. This helps you concentrate on rotating around the shoulder and feeling that stretch. You'll notice that the windmill motion tends to go inward (toward left side fence) as you complete first half of windmill/stretch the shoulder, and then "outward" (away from left side fence) as you complete the 2nd half of the circle.

    Do this a few times and then your brain commits it to muscle memory.
     
  24. Ross K

    Ross K Legend

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    tricky,

    Okay. I getcha now. ;)

    BTW, spent some more time earlier today on the court working on the Nadal/Gasquet serve and the Henin serve. For some reason, this time I semed to find a little extra solidity and oomph with the Henin motion and not the Nadal version (a reversal of a few days ago.) This surprises me a bit as the Nadal/Gasquet is pretty similar to my usual serve, whereas the Henin arms move together upwards into a V shape-motion is new to me, and feels altogether less dynamic with its simple upright and linear motion... hmmm... could it be a case of simple equals better in this instance? Anyway, I'll keep alternating and experimenting for a little longer (whilst trying out a lot of the info you've provided) before settling on one motion.
     
  25. adlis

    adlis Professional

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    here is a great example of the stretch

    [​IMG]
     
  26. shwetty[tennis]balls

    shwetty[tennis]balls Rookie

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    How about not serving with jeans on!
     
  27. hyogen

    hyogen Hall of Fame

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    man his feet are right next to each other!!!!!
     
  28. HappyChappy

    HappyChappy Rookie

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    tricky

    I am beginning to think that the:

    'depth of racquet drop indicates potential racquet head speed'

    is just plain wrong

    what do you think?

    The bigger the backswing the greater the power?
     
  29. sharpy

    sharpy Banned

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    deeper the drop the more potential power as there's more room for racket head acceleration...
     
    Last edited: Nov 15, 2007
  30. HappyChappy

    HappyChappy Rookie

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    that statement assumes it take ages to build up racquet head speed, which is not necessarily the case:

    In the following examples of some of the biggest servers of all time, most of them: flip, rusedski, KRAIJECK,lubijic, have completely normal racquet drops to your average joe, (about down to your ass)

    Sampras and roddick have racquet drops down to their knees, but then again, so do gasquet and dementieva!

    And don't forget our good friend hyogen

    Can't say for cerain about the others, but rusedski's serve has been clinically proven to have the same average mph and spin,(rotations), per minute as Sampras's.This means he's actually producing the same amount of racquet head speed, which means his ARM is moving the racquet through space as quickly, which means his height has nothing to do with this.

    great servers:

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    continued..
     
  31. HappyChappy

    HappyChappy Rookie

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    great servers continued:

    [​IMG]

    some not so great servers:

    [​IMG]

    [​IMG]

    (hyogen)

    [​IMG]




    I see no correlation between serve,(racquet head) speed and racquet drop here.

    Can any of you honestly say you do?
     
  32. sharpy

    sharpy Banned

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    lol hyogens racket drop is under 'not so great servers'
     
  33. 1337Kira

    1337Kira Rookie

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    What exactly is this "trophy position"? Some of the posts say its when you point straight up, but I'm a bit confused to this, could someone explain it to me?
     
  34. sharpy

    sharpy Banned

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    happy.. with those angles the drop looks the same for every player can't tell the difference!
     
    Last edited: Nov 15, 2007
  35. ananda

    ananda Professional

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    1. A question about KNEE BEND. Is a deep knee-bend critical to a good serve. I have been noticing Fed has a very light knee bend, otoh Davydenko has a very deep bend but perhaps less effective serve.

    2. Adlis, who is the person in the pic in Post #125. is it a well-known pro?

    3. A question about RACQUET DROP. at the point of/after trophy pose, if one consciously thinks of getting the elbow up, (i have been trying this out shadow serving), does this result in a good rack drop and resultant throw of the racket upwards and forwards. Another thing i was trying was keeping the grip loose, trying with only 3 fingers, and this seemed to help in rack drop too.
     
    Last edited: Nov 15, 2007
  36. Ross K

    Ross K Legend

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    Q for all:

    Because I've been experimenting recently with both the Nadal/Gasquet serve motion and the Henin motion, I was just wondering who everyone else might have studied and copied to some degree.
     
  37. Ross K

    Ross K Legend

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  38. Ross K

    Ross K Legend

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    ^^^

    BTW, the coach is called *Dan Brown and the vid compares some of the serve mechanics of a regular Joe with Thomas Johanson and Rafa Nadal. Maybe ppl are familiar with this instruction series already but it's new to me and seems impressive... BTW2, hey tricky, when are you gonna put out some vids!?... I'd absolutely tune in to those for sure!

    * Er, I have a feeling it's not the same Dan Brown who wrote The Davinci Code. ;)
     
  39. HappyChappy

    HappyChappy Rookie

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    racquet drop can be down to:

    1)waist

    2)ass- kraijeck

    3)thigh-dementieva

    4)knee-sampras

    that's how you measure it
     
  40. ananda

    ananda Professional

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    you should look at the fuzzyyellowballs.com site.

    i tried out copying the sampras style since it seemed somehow closest to what i was doing. i got it quite well except for one thing. The knee bend in his first serve is quite "tricky". He seems to sit into the court, backwards.
    Then i got this while shadow serving but was unable to get it on court.
    However, i am unhappy since i am not getting pace on the serve with this style.

    In my last session, i spent some 15 mins, trying out other styles. One, the simpler, pinpoint stance much like (say Ferrer) most do. Got a few good slice serves in. Then i tried just focussing on keeping right shoulder low and aiming for sky (like Tricky had mentioned), and i got 2 fast serves in, but netted the others.

    At this point i think rather than copy one serve, i need to figure out what works for me, through some trial and error, and keep it simple.
     
  41. BrianGordon

    BrianGordon New User

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    Good discussion folks - several interesting points raised - my take:

    Like nearly any individual component of the serve, one would be hard pressed to show correlation to contact racquet speed, over a variety of different servers, because so many other factors are combined in the process.

    It is a little bit like saying my 64 VW bug and my Ferrari both have four wheels but that does not correlate to the speed they can clock. It disregards the engine.

    Seems to me the serve is no different. More important than the depth of the drop is the conditions of the body and racquet at that instant, and the muscular engine that will take the racquet to contact.

    That said, for a given engine, the longer the distance over which it can exert its drive (deeper drop), the faster it will ultimately drive the machine.

    For the sake of discussion I would suggest that the only way to assess the correlation of drop depth to contact racquet speed (and therefore its importance) would be to remove the confounding variables (the engine).

    Of course, this is impossible, but if Pete Sampras could hit two serves keeping all else constant, but in one he uses full racquet drop, and in the other he uses 3/4 of the drop, which serve would show the highest contact racquet speed?
     
  42. HappyChappy

    HappyChappy Rookie

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    The important question is this, how long does it take the arm to reach terminal velocity?

    If this can be achieved almost instantaneously then the depth of the racquet drop is irrelevant, if this takes time to build up to, then racquet drop is crucial.

    You would imagine there would be an initial inertia to be overcome before any real speed could be built up, (this is why a continous motion is better than a halting one).

    This question could be answered fairly definitively with some quantative measurements of racquet head speed at various stages between the racquet drop and impact.If for example, maximum speed is achieved instantaneously and continues at this pace for until impact, you could say that racquet drop depth is irrelevant, if the racquet head speed was shown to be gradually accelerating right up to impact you could say assume the opposite to be true.
     
  43. HappyChappy

    HappyChappy Rookie

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    perhaps the speed of the progress of the hand should be measured as there is always gradual acceleration of the racquet head due to the role of the wrist.
     
  44. BrianGordon

    BrianGordon New User

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    The solid line is the racquet head speed of nine NCAA DI servers combined - disregard the dots as they are the predicted racquet head speed based on the speed of the various joint rotations - the speed is measured using 3-D data acquisition.

    Don't get me wrong - I like your thinking - in fact, I think if you go a level deeper and consider the motions that create the drop it will add a lot to your analysis - starts to get more into the "engine".



    [​IMG]
     
  45. Mike Cottrill

    Mike Cottrill Hall of Fame

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    Hi Brian,
    Could you please explain the significance of the time scale (X axis)? Time to impact from server to server varies; for example Todd Martin virus Jim Courier. One is slow and smooth and another is fast and jerky.

    On a side note, have you used your technology to identify stresses and ways to reduce stress and injuries in the mechanics without losing performance and efficiency?
    Thanks
    Mike
     
  46. BrianGordon

    BrianGordon New User

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    The time scale is absolute in seconds - individual trials were split into discrete segments and the time scales normalized, then reconstructed to create homogenous averages - 10.0 is arbitrarily assigned to contact to avoid those nasty negative numbers. Individual plots do vary but all that I've measured are roughly upwardly curvilinear like the composite shown. Some have irregularities which can be traced to mechanical errors.

    I always try to identify mechanical errors that I believe will cause injury - some are obvious but most are very difficult to quantify - so my first line of defense is targeted physical training.
     
  47. Mike Cottrill

    Mike Cottrill Hall of Fame

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    Thanks,
    The normalized time to 10s makes since now.

    From what I understand Todd Martin changed his take back because of injury and to prevent further injury. If this is correct, I wonder how he came to the conclusion the new take back he is using actually is reducing the stress. Did he have someone like you do an analysis or just experiment and “think” he found something safer for is shoulder. Your thoughts?
    Here is link to his new take back in high speed film.
    http://www.hi-techtennis.com/serve/martin_serve_open.php
    Thanks
     
  48. BrianGordon

    BrianGordon New User

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    Logically, I've never been able to come up with a reason why the take back would alter injury dynamics - I believe Henin did the same - one possible reason is the speed at which the arm enters the back swing loop may cause excessive shoulder external rotation stress later in the back swing (but I doubt it) - I've heard most make the change based on experimentation and not quantifiable analysis - one research study looked at the loading dynamics at the shoulder and elbow based on take back style - they found no significant difference in stress levels at either joint based on take back - the extent of the leg drive did, however, play a much bigger role in this stress.
     
  49. Mike Cottrill

    Mike Cottrill Hall of Fame

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    Great stuff,
    Wow, that is interesting that leg drive effected shoulder/elbow stress. I figured that affected the back or at least more. Great stuff.
     
  50. Ghosting

    Ghosting New User

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