Hitting-shoulder transversal extension/flexion in forehand

Discussion in 'Tennis Tips/Instruction' started by albesca, May 7, 2012.

  1. albesca

    albesca Rookie

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    Hi guys. I've a question.

    How important is to relax and pre-stretch the hitting shouder with an external rotation movement, at the end of the backswing ?

    [​IMG]

    Ciao
    Al
     
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  2. Chas Tennis

    Chas Tennis Hall of Fame

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    That's a great question. I think that the pre-stretch is very important in all speed activities. (External shoulder rotation is defined by the axial rotation of the upper arm bone.)

    Which muscles are stretched for the forehand? I just started studying the 'current' forehand. In my opinion

    1) the trunk is stretched by the 'unit' turn,
    2) the pec is stretched, and maybe that is one reason the elbow should be raised, to stretch the pec more?
    3) the elbow is raised up also so that the lat can contract to bring the arm back down, but is the lat stretched?

    The shoulder muscles themselves, the anterior, medial and posterior deltoids are shortened with the elbow up so that the upper arm is straight out or slightly forward as recommended in the 'current' forehand. In your picture of Djokovic his upper arm is slightly forward (of a line drawn between the shoulders).

    I like the Rick Macci forehand instructions and description although there is not much identification of the muscles involved. I can usually identify several of the muscles that are being stretched but I'm not certain. I believe that Macci says the upper arm should always stay parallel or slightly in front of the line between the shoulders as in the Djokovic picture.

    Since you are interested in the subject I'd recommend getting a book on Kinesiology which illustrates the muscular movements, identifies the muscles involved and gives the proper name to the specific motion. Internet is very good too.

    Find an older edition 17th?, or 16th, etc.of this popular college text. Latest edition $75, recent older edition $5, etc.

    http://www.amazon.com/Manual-Struct...=sr_1_3?s=books&ie=UTF8&qid=1336384795&sr=1-3

    Research stretch-shortening cycle. I like the stretch-shortening cycle discussion in the Biomechanics of Tennis Technique, D. Knudson.
     
    Last edited: May 7, 2012
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  3. jk816

    jk816 Rookie

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    Don't forget the forearm flexors; as the swing starts forward the racquet head drops supinating the forearm flexors, putting them under tension rather suddenly and they stay that way up to the contact point where pronation occurs (moreso with a WW style, but part of any TS forehand). That puts a lot of stress on the forearm flexor group, as any sufferer of medial epicondylapathy (GE) has learned, worse if the racquet is gripped too tightly.
     
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  4. albesca

    albesca Rookie

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    imagining a "frontal muscle chain" from the right shoulder to the left hip, we would have to pull (stretch, load ...) the frontal elastic during the back swing so that it, after, can push (release energy) ...

    [​IMG]
     
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  5. tricky

    tricky Hall of Fame

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    Mmm, it should be loaded earlier, during the unit turn. If it's introduced at the end of the backswing, then you'll see timing problems. This is actually what happens when people have footwork issues and try pivoting around the front foot. This goes back to how many people misunderstand the role of the non-hitting hand during the unit turn. The unit turn itself should be initiated by the separating of the non-hitting hand from the racquet. If it isn't, then the shoulder will not be loaded to rotate until the initiation of the forward swing, which will throw off the timing of the swing. It's actually the combination of the non-hitting hand and the momentum of your movement that causes the trunk to turn and stretch. This is also why footwork is so important.

    Medial rotation of the shoulder (as well as the hip) is difficult to isolate within a throwing or swinging motion. However, it's tightly related to your balance/momentum. The most efficient way to load your shoulder is to check your head movement. As you initiate the unit turn and go through your backswing, the back of your head should start to move forward or away from the back fence.
     
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  6. Chas Tennis

    Chas Tennis Hall of Fame

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    Great concept and illustration. For whatever reason some muscles seem to be favored while others are not. Very unclear why. (Each decade the relative stretch for each muscle will change are we are seeing.)

    For example, to stretch the pec to the maximum the upper arm (humerus) would be dynamically brought back behind the line between the shoulders. That's not done in the forehand described by Rick Macci as the current. The current forehand takes the upper arm somewhat back but not as much as for a full stretch. Does that mean that stretch of the pec is not very important and that the trunk turn (stretched?) is supplying most of the final power for racket head acceleration. Videos could be interpreted that the pec contraction does not produce much power since the upper arm does not move toward the chest that much until after the hit.

    In videos of pros I sometimes see what looks like a fast trunk stretch and other times there is so much delay - 1 second - that I don't think it can be important. ?

    Internal shoulder rotation (as anatomically defined) can be seen just prior to and in the follow through.

    From simple one camera videos it is difficult to understand whether some motions are really powered joint motions or just passive low-force joint motions. Determining the muscle power supplied can probably be done with multi-camera research motion capture systems that can measure acceleration for each joint. Most of the biomechanics research is top secret or often $50 a paper.

    Also, my understanding of the basic stretch-shortening cycle is not complete enough. I'm unclear as to whether an effective stretch can only occur at on near the end of the joint's range of motion. I think that's the case for the tennis serve but not for the quads in walking or jumping. ? Maybe only the stretches to the end of the range of motion are useable for the fast shortening. ?
     
    Last edited: May 7, 2012
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  7. boramiNYC

    boramiNYC Hall of Fame

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    It's a great technique. That's what makes Djokovic forehand special. If you can do it, do it every time.
     
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  8. enishi1357

    enishi1357 Rookie

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    i dont think it is neccessary at all. then again since he has a western grip he has to do that or he can't generate any pace.
     
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  9. albesca

    albesca Rookie

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    In single-shoulder back to front movement, isn't there only a pectoral pulling action, but also, back-muscles pushing action (rotator cuff, l. dorsi exc..) and, maybe, that single-shoulder movement could be a great power supply...
     
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  10. albesca

    albesca Rookie

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    Tricky, i seem it is impossible or so to do a single shouder external rotation before the core loading/rotation ends ... agree with you a full pec stretch needs a timing adjustement...

    pivoting around the front foot, to me, happens due a too long legs/hips activity in contact zone too ... . Legs and core have an active role, imho, only for some degrees of rotation... as engaging the first and second gear in a car, but as the raquet is near the contact zone, we need speed, and the arm can mesh third and fourth gear. Imho, by isolating a arm-only activity in contact zone, can't pivoting and have a better balance.

    Just keeping the shoulder relaxed and pull back with the elbow as we have shifted the body weight on back foot ( open and s-open stances), and doing a full rotation/loading of hips and trunk. Yes, it isn't so easy as it seems... but not so difficult .
     
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  11. tricky

    tricky Hall of Fame

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    For throwing and swinging motions, hip rotation and shoulder rotation are usually connected. Where people get confused is in presuming hip rotation and pelvic turn are one and the same. Not so.

    If you want to isolate internal rotation as a movement proper, what you can do is visualize your two shoulders as being connected by a rubber band. When it is loading (passively rotating externally), that rubber band is being stretched. When it is contracting internally via SRC, that rubber band contracts. This also works in demonstrating hip rotation and its role in weight transfer.

    In the example, where you discuss a rubber band connected between hip and shoulder, that demonstrates an example of transverse adduction. Transverse adduction more or less defines the line of the swing, and your ability to drive through the ball. It is an important part of the shape of the swing (straight-arm FH can be defined as a swing where this aspect is highly loaded), but people tend to confuse this as internal/external rotation.

    Realistically, medial rotation of both hip and shoulder will be dependent on footwork patterns and movement. If the footwork isn't there, then even if you take a big cut at the ball, your shoulder isn't being loaded efficiently.

    For the forehand, the lats help out with the loop (positive adduction, negative abduction) of the movement. It doesn't play a major part in internal rotation for the FH, but it does play such a role for the serve.
     
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  12. albesca

    albesca Rookie

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    interesting, thank you Tricky, more about ?
     
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  13. Chas Tennis

    Chas Tennis Hall of Fame

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    I don't know the relative contribution of the pec in comparison to the uncoiling of the trunk. This stroke breakdown video on tennisoxygen is very detailed and identifies "common threads" in the forehand. (Tennisoxygen has an excellent series of 65 similar videos detailing the strokes.)

    http://www.youtube.com/watch?feature=fvwp&NR=1&v=_Oc7U5oJ6ps

    My Video Observations Trunk & Pec - At first the trunk rotates and carries the upper arm. If you look at shoulder movement driven by the pec (as when the upper arm moves across the chest) this motion becomes apparent just before the hit with some motion but most of this motion follows the hit. In has to be kept in mind that even though some motions have just started in videos they may still have achieved a high velocity if powerful. Also some motions in the videos are not driven by muscles but may result for de-acceleration or follow through.

    In my opinion, these forehands are the 'current' forehand of the top pros and the same forehand as described by Macci.

    (I'm am now trying my interpretation of this current forehand, swinging with just the racket. It makes my wrist hurt just beyond the hit range so probably I'm doing it incorrectly. I'm analyzing proper forehand before any practice.)

    All muscles can only pull like ropes. The rotator cuff does not supply power, it holds the head of the humerus into the shoulder socket, the big lat muscle can pull the upper arm down as in a pull-up or internally rotate the upper arm as in a tennis serve (old school tennis mislabeled as 'pronation'). The lat and the pec attach on the same spot of the upper arm and can move it in similar directions for some orientations of the upper arm. http://www.exrx.net/Articulations/Shoulder.html

    I believe that there are differences in international usage as when I go to Wikipedia the terms are not as used in the US. Which shoulder movements did you intend by "shoulder external/internal rotation"?
     
    Last edited: May 8, 2012
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  14. albesca

    albesca Rookie

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  15. Chas Tennis

    Chas Tennis Hall of Fame

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    In the first diagram of the lat muscle, "d" is internal shoulder rotation as used in the US. As used in the US external shoulder rotation is not illustrated. (The website identifies a muscle and then shows the movements that it contributes to. Better to have the joint movement and all the muscles that contribute to it. The lat contributes to internal rotation and is loaded by external rotation.) Also, the diagram may not be clear but the lat muscle attaches to the upper arm on the front, a very important point for understanding shoulder movements. Not certain what "b" movement is as I am uncertain of translation but its function looks more for scapular positioning than power producing.

    Believe it or not "d" /internal shoulder rotation as shown provides the greatest contribution the racket head speed in the serve!!

    In the second diagram, the muscle shown is the serratus anterior muscle (gran denato) mostly a stabilizer for the scapula and does not produce much power or movement.

    If the diagrams showed a view from above they might be more helpful for the forehand motions.

    Movement definitions - Link that has videos of exercises with shoulder joint terms as used in the US. Keep in mind that these are exercises and the weights or pulleys provide force in the opposite direction to the named shoulder joint movement.

    http://www.exrx.net/Articulations/Shoulder.html

    I learned something new as I was badly misusing the term flexion for the shoulder and now am a little confused by the terms flexion, transverse abduction, and transverse adduction. The shoulder is the joint with the most complex compound motions.
     
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  16. Chas Tennis

    Chas Tennis Hall of Fame

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    For most top pros using the 'current' forehand there's one hand on the handle, a hand stays on the racket throat and the line between the shoulders turns roughly 90 d. (from parallel to the baseline). The line between the shoulders and each arm form sort of a 'triangle' as described in some videos that aids in turning the upper body/trunk back as a 'unit'. It may not be necessary to keep the hand on the racket throat but it probably helps to get more reproducible strokes. Keeping the non-hitting hand on the racket also probably keeps the hitting arm from going back farther than the line between the shoulders. Macci says that the upper arm is best a little forward.

    This video describes that the non-hitting hand stays on the racket until just before the start of the forward swing for the current top pro forehand.

    http://www.youtube.com/watch?feature=fvwp&NR=1&v=_Oc7U5oJ6ps
     
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  17. tricky

    tricky Hall of Fame

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    Hip rotation is often visualized as the pelvis turning around the spine. This is not 100% true.

    Visualize your hip sockets (i.e. where legs meet the hips) as two points, A and B. From where you stand, visualize that point A is pulling away from point B. You'll notice that your weight is transferring from point B to point A, but that your pelvis isn't turning that much. Instead, you are turning your left leg out. This is one isolated example of hip rotation.

    As you initiate the unit turn, these two points should be pulling away from each other. If it isn't, then the hips are "closed." This is dependent on footwork patterns and momentum, rather than stance. You can have a semi-open stance and almost no hip rotation through most of the swing. You can have some hip rotation even from a closed stance. It depends on the sequence of step patterns.

    The above is why I always encourage people to go through the one-foot drill when learning the unit turn. When you start separating the hand from the racquet (whether it's moving the hand forward or lifting the throat of the racquet), the trunk automatically turns. By the time the hand has fully separated from the racquet, the trunk is roughly square with the back fence. It doesn't feel that way, because the trunk turn is a passive movement, but in the mirror, it shows as such.

    Ideally, the trunk and arm work as a counterbalance against the non-hitting hand. Through this, the unit turn loads the kinetic chain above the waist. But this can only be done if the person consciously starts to separate the non-hitting hand from the racquet.

    When a person consciously holds onto the racquet throat during the unit turn, this causes the shoulder to actively rotate externally in the backswing. This creates hitches in the stroke (i.e. "arming the stroke"), such as the hitting arm moving past the line of the shoulder. Also, this causes contact point and timing problems because the shoulder is no longer loaded to rotate internally, until the pelvis turns suddenly into the ball.
     
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  18. Chas Tennis

    Chas Tennis Hall of Fame

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    My usage of the term 'unit turn' is both for the back swing and the forward swing. Is that your usage?

    The video shows the hand on the racket throat for the initial part of the back swing until the line between the shoulders is about at right angles to the base line. The elbow is up away from the side and slightly forward of the line between the shoulders. Just before or then the hand comes off. This is much more holding onto the racket than I have ever done.

    Do the videos match your non-hitting hand description? Could you indicate the frame in the video (by second) that the hand comes off and its relation to the progress in the unit turn as you are using the term?
     
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  19. albesca

    albesca Rookie

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  20. albesca

    albesca Rookie

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    i seem hip rotation happens due the two legs rotation in some direction, around their femoral axis and due the gluteos push/pull action... maybe it is in according in what you said..
     
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  21. tricky

    tricky Hall of Fame

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    @Chas,

    I'll follow up with you when I get home. No YT at work. :(

    It depends on how the person uses ground reaction force. If it's a general upward, then the trunk and pelvis tends to turn as one unit, If the momentum is more forward, then there's some separation or twist between the trunk and pelvis. Sequencing figures into this. As the FH is often taught nowadays, the shoulder will abduct (passively) before rotating externally (and passively.) This leads to a loopier swing, more obvious trunk rotation, and the non-hitting hand staying on the racquet longer.

    Transverse flexion figures more into the extension of the elbow through the contact point. Federer is unique in that he loads this part in his backswing, which enables him to drive through shots at remarkably velocity without swinging "hard." However, this is somewhat inhibited depending on the overall mechanics of the swing.
     
    Last edited: May 8, 2012
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  22. albesca

    albesca Rookie

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    abstract from Coachesinfo.com: http://www.coachesinfo.com/index.ph...e&catid=95:tennis-general-articles&Itemid=173

    Recent biomechanical research on tennis groundstrokes has shown evidence of sequential coordination and stretch-shortening cycle muscle actions. Today, groundstrokes are coordinated much like the serve, with well-timed sequential actions of body segments. For example, in an open stance forehand as the speed of trunk rotation peaks this stretches the chest muscles, storing elastic energy. As trunk rotation slows (Knudson & Bahamonde, 1999) before impact some of this energy is recovered as the chest muscles accelerate the upper arm.

    In order to the stretch-shortening cycle Chas said, here would be an answer to my question: relaxing the shoulder (so it extends back) is not enough. We would have to relax all chest muscles as the trunk accelerate, hitting-shoulder muscles too.

    Then, if i have well understood, all chest muscles need to be stretched, not only the hitting shoulder... and, before impact, that stretched muscles will be the protagonists during acceleration of the arm , trunk rotation slows down so we can't pivoting off balance.... it seems have sense...
     
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  23. Chas Tennis

    Chas Tennis Hall of Fame

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    Change gears and watch a great example of the stretch-shortening concept with the muscles that we are discussing-

    http://www.youtube.com/watch?v=wCHHev-5K3Q

    It is well worth watching from the beginning. But starting at 9:49 press the play-pause button as fast as possible. Can you see it at 9:51? I have seen better videos of the punch. There was a lot of controversy afterward about the 'punch from nowhere'.
     
    Last edited: May 9, 2012
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  24. Chas Tennis

    Chas Tennis Hall of Fame

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    terms, stretching sequence

    My usage - The 'shoulder' muscles are often understood to be the anterior, medial and posterior deltoids. I see the stretch more easily in the trunk, and pecs and not as clearly in the deltoids. To some degree the anterior deltoid works with the pec, I guess.

    In the US usage, the term 'agonist' is the muscle that creates the movement with 1) deliberate contraction, or 2) deliberate contraction + stretch or 3) just stretch with no considerable deliberate contraction. The antagonist muscle creates the opposite motion (to the agonist) at the joint and usually is very low force for control when the agonist is really working fast. I believe that when you get 'tight' in a tennis match the antagonist are supplying too much force and it screws up your timing.

    Speculating - I am not sure why the big muscles must slow down before the smaller muscle can do its thing. I believe that the bigger muscles may slow because otherwise the smaller muscle might not have enough force to overcome the force the bigger muscles are supplying. Think of being pinned in the seat of an accelerating rocket.

    The chest muscles probably could be stretched over a short distance as the trunk accelerates.

    I have a book that show these forces in sequence. It is an injury rehabilitation book and there must be biomechanics texts for tennis with better descriptions.
     
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  25. tricky

    tricky Hall of Fame

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    This goes without saying though. Most shoulder movements involve many muscles including the pectorals and lats. Also, some of these movements (int/ext rotation) can be performed with two different groups of muscles. For example, the shoulder muscles you use to serve are different than what you use for the forehand.

    This is more obvious if you look at Vic Braden's skeleton clips. However, if you prestretch the shoulder just before you swing, the trunk rotation will not slow down as you swing through the contact point. The non-hitting hand works as a brake to slow down trunk rotation (more or less in the same way one usually uses it while throwing.) However, if the shoulder isn't sequenced properly, then the non-hitting hand literally has to do "get in the way" of the trunk in order to slow down. Something gives. Either you lose swing speed before your racquet goes through contact point, or you can't properly drive through and fully control the direction of the ball.
     
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  26. albesca

    albesca Rookie

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    You said: "The chest muscles probably could be stretched over a short distance as the trunk accelerates."

    So are you agree in what it is reported in coachesinfo.com ?
    In ur opinion, (i'm repetitive...sorry), is this the correct chest-stretch timing ?

    Great video Chas .. thank you.

    Thank you guys.
     
    Last edited: May 9, 2012
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  27. tricky

    tricky Hall of Fame

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    I think you meant Chas, but I'll speak to this . . .

    Yes and no. When people talk about ballistic motions (stretch-release cycle), you also have to talk about sequencing the kinetic chain. The SRC is dependent on the muscles being "released" to being loading in sequence from the beginning. If another chain is added midway, it can throw off the intended movement pattern, or it can cause the SRC to be suppressed.

    The chest muscle starts to get stretched during the unit turn itself. This is because the chest muscle is also responsible for the adduction (the vertical portion of the loop) of the swing. What loads the chest muscle? 80% of it is due to the intention of the non-hitting hand separating from the racquet. This causes your chest and shoulder to stretch against the motion of the non-hitting hand.

    BTW, visualization can help . If you want to improve internal shoulder rotation, visualize the ball being filled with concrete (i.e. "heavy") You'll notice some activation in your glutes, leading to a stronger "sit", and in turn you'll notice your shoulder rotation being much stronger.
     
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  28. albesca

    albesca Rookie

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    I finally understood (hope !).

    You're talking about the moment in which the non-dominant arm, starting from the extended position it is being pulled back and close to the body ! So the hitting arm has a passive role (or so) in chest loading.. just stay relaxed to create a certain delay from shoulder to shoulder so the chest opens and loads ...

    [​IMG]
     
    Last edited: May 9, 2012
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  29. tricky

    tricky Hall of Fame

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    Yup, this part reflects the "braking" portion of the stroke.

    The trunk and pelvic rotation during the unit turn is mostly passive (i.e. stretch), not active. This throws people off, because it doesn't seem like that is possible from watching video clips. It's easier to understand if you try executing a unit turn while standing on just your right foot. Your balance should be moving forward, so that you end up landing on your left foot. If your unit turn is off, your balance will go sideways or backwards.

    You'll notice that manually turning the pelvis/trunk, or holding onto the racquet with your non-hitting hand causes your balance to go sideways/backwards. You'll find that in a "correct" unit turn, you don't even notice your trunk rotating that much, even though the mirror shows a strong unit turn. This is because your brain doesn't "trace" the motion of muscles passively loading or stretching.
     
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  30. albesca

    albesca Rookie

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    Perfect tricky.

    Then, the first part of a forehand SRC sequence, to a right handed, would be:

    1. gripping on the ground with the right foot (distance control);
    2. bending the right leg and let the trunk and hips naturally turn taking advantage from the balance shifting towards the right leg (unit turn). The shoulders line will be squared to the net and the non-dominant arm must be stretched out towards to the side;
    3. the return of the trunk starts with an active movement of the non-dominant elbow to the left (timing control). It opens the left shoulder and stretches the chest muscles. At the same time the right leg pushes against the ground and the hitting arm leaves the wrist laid back.

    Now I hope to be pretty close ... :)

    Many thanks.
    Ciao
    Al
     
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  31. GuyClinch

    GuyClinch Hall of Fame

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    Not gonna lie - this thread confuses me. So what did we decide - externally rotate the shoulder there in the backswing stage..? This kinda gives you more windup in your windshield wiper action or not?
     
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  32. crosscourt

    crosscourt Professional

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    This is fascinating but I am a little confused too. Does this all happen automatically if you lift the racket head up in a loop with the hitting face towards the side fence before setting back with the tip of the racket towards the back fence (in a r/h f/h)?

    And having got the stretch what is the best way to move the racket forward? With a slight forward motion of your shoulder? That seems like the quickest way to get your arm moving forwards. Or is that missing the point?

    CC
     
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  33. Chas Tennis

    Chas Tennis Hall of Fame

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    I don't understand much of the detailed muscle-by-muscle breakdown or sequencing. First I'm trying to understand mainly the part played by the stretch-shortening cycle for the bigger muscles and check it with the timing I see in the video linked above, other forehand videos and the Macci instructional video.

    http://www.youtube.com/watch?feature...&v=_Oc7U5oJ6ps

    In the back swing if you move your upper arm as in the 'current' forehand - to parallel to or slightly forward of the line between the shoulders with the forearm roughly horizontal - what is the external rotation of the shoulder (axial rotation of the upper arm)? There is not much external shoulder rotation, it is sort of in the middle of its range of motion. Maybe the forward trunk rotation causes external shoulder rotation which would stretch the internal shoulder rotators?

    I think that what goes on is that the forward trunk/body turn stretches the pec and maybe the other internal shoulder rotator muscles. These muscles contract using stretch + deliberate contraction in some unknown proportion to produce racket head path & speed.

    The trunk rotation-chest stretch was the point of the Muhammed Ali/Oscar Bonavena knockout video. Ali rotates his body while holding back his arm. It looks as if he is stretching mainly his pec and then he lets it go - very fast - the 'punch from nowhere'.

    I have come to believe after reading some discussion in the Knudson book, Biomechanical Principles of Tennis Technique, that a muscle using stretch is faster than a muscle using just deliberate contraction.
     
    Last edited: May 11, 2012
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  34. boramiNYC

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    When the hand is twisted that way, all the muscles leading to it must be stretched and better primed for coordinated action. No idling piece in the chain and no forcing and out of control. This is not a must but definitely the best technique for any grip. There's whole lot more to the overall coordination but that twist is golden.
     
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  35. Chas Tennis

    Chas Tennis Hall of Fame

    Joined:
    Feb 17, 2011
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    Shoulders turn back more than hips...angular difference

    I recalled this interesting thread on forehands.

    From Technical Development in Tennis Stroke Development (2009), B. Elliott, M. Reid, M. Crespo, ITF publication, $20

    Unit turn - This reference says that there is a larger take back angle for the line between the shoulders (when viewed from overhead) when compared to the angle of the line between the hips. This greater shoulder rotation prestretches the trunk muscles for the forward swing. I understand this angle better after reading the discussion in the book. (Also, the 'unit turn' is not literally a unit turn I guess.......)

    Albesca, How are you doing with your forehand?
     
    Last edited: Sep 3, 2012
    #35
  36. akamc

    akamc New User

    Joined:
    Mar 20, 2005
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    91
    Tricky,

    I am a little confused by your description above. Which hip socket is A and which is B (say for for a right-hander)? And since they are both fixed on the pelvis, how can A pull away from B?

    Also, when you say that the hips are "closed", do you mean that they are facing the right fence (for a right-hander), and is that bad?
     
    #36
  37. albesca

    albesca Rookie

    Joined:
    Jun 18, 2008
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    Location:
    Milano, Italy
    in the past I was convinced that the upper body rotate over the hips at waist separation level. Using the shoulders in a conscious and relaxed way, however, I feel that it is another separation level in the trunk, higher, just below the pectorals.

    My new belief is that it is not only the whole trunk rotates over the hips, but also the upper trunk rotates above the bottom trunk, stabilized by the abdominals.

    In essence, if I loose both shoulders over solid abdominals during the forehand preparation, seem i create ideal conditions to develop power and good coordination.

    But this clear improvement in power needs more control ! Now i'm experimenting on hand leverage at contact to have both power and spin and avoid to do a hole in the opponent back fence... :)

    In my 1h backhand, the shoulders relaxing over solid abs works too .. and i have found good control too by supinating the hand/wrist/foreharm in contact zone. In forehand i'm not able to do the same yet...

    Ciao
    Al
     
    #37

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