Racquet snaps the wrist on serve...

[julian1]

Do we accelarate on a contact point of forehand?

Thanks, Julian. That was really great. I've now done my mental gymnastics for the whole day, maybe even the whole week.

Wow. Talk about paralysis by analysis. I'm not even going to consider linking to the American Jounal of Physics article. I probably need to read that a couple of times to really digest it, but there are a few things that this article validates on a more applicable level.

(I like to think my students walk away from my lessons thinking, "Wow, that was interesting. Don really knows what he is talking about!". This is great information for me, but I already have a reputation for being too technical. If I integrate too much of this overtly into my lesson presentation, as true as I believe it must be, students may be really fascinated during my presentation, but as they don't get to "reread" that presentation, they will probably walk away saying, "What the hell was that about?!")

So:
1. Trying to hit your serve "harder" when you are serving really well will probably make the ball go slower, if not totally destroying your rhythm and effectiveness. Hit it "faster", not harder, by releasing more completely.

2. On the groundstrokes, use the wrist as a "passive hinge" controlling the ball, but not snapping through it as you try to keep the strings on the ball as long as possible.

3. In the same vein as the passive hinge, try to swing the racket head, not your arm or your hand. This means the wrist maintains its position and slight wrist cock as you swing forward to the ball on the forehand.

4. On the other hand, this validates Phil's effort to emulate the Federer wrist extension/flexion flick at the beginning of his forehand forward swing.

I do think we missed a whole lot of stuff here about internal rotation and the optimum angle of the racket shaft to the forearm to create effective power from internal rotation (you don't get much if the upper arm, forearm and racket shaft form a straight line...which they do in the frying-pan-grip-serve used by rank beginners). I wish we could get a comment from Rod about where that fits into the picture. Probably, I just need to do a little more reading in "The Physics and Technology of Tennis" (Is it in there, Julian?)

Well, that's good for a start on Sunday morning. Curious to hear what the rest of you think.

don

Do we accelarate on a contact point of forehand?

[tennis_chiro]

So nice to hear about gravity!

So there is always one more thing. After the student has mastered his "figure eights" and developed a gravity based and frictionless swing and the wrist is behaving itself...the whole thing is dependent on one more thing. Putting the ball in the path of the traveling racquet head. This can be very disruptive to the whole process.

There is basically one point in time and space where it all collides simultaneously, and perfectly...where the grip, the motion and all of the generated energy meet the ball. Any deviation from this one point in time and space will produce less than "perfect" shots as energy and potential energy will be wasted or erratic.

I call this point "it". Musicians get it...the whole craft depends upon it. Golfers get it. Tennis players get it. Great oraters get it. Anybody who successfully and repeatedly is accomplished in anything in any walk of life gets it. It's too bad more people don't get it...have you ever known anybody who just doesn't get it. But...it is not so easy as that when you are trying to deliver the ball to that one point in time and space in order to put the ball right where the ball should be, and when the ball should be there. When and where...time and space.

As tennis players, this in the end, is the object of our craft also...we seek to find that one point in time and space where everything is perfect. This relates to our serves, our groundstrokes, to those of us hitting the ball in the air still it relates to our volleys. It relates to every single type of shot under the sun. The quest as it were, is to get the grip right, get the feet, body and racquet into position, and then move all the responsible parts to get the racquet head to meet the ball the way we intend it to when we attempt any particular shot. The ultimate challenge for a human being is to have that kind of control over ones self to master such an endeavor. This is why golf and tennis are God's gift to humanity in terms of at recreation...possibly even more significant than that. There are physics, in a "perfect" world and there are the metaphysics in the real world as we know it. Rod Cross is great but he has left a huge variable out of the equation while focusing on some others. But don't get me wrong, he is fine in a certain sphere of influence, I think.

Perhaps a new thread...and a couple of more videos from Coach Don on the toss...in order to assist the student to find "it". Excellent job, Coach...btw.

I have to say, Steve, I rarely if ever find anyone who wasn't one of my students who is so in tune with my emphasis on the use of gravity in developing a consistent toss. Gravity is really wonderful. It doesn't change appreciably from Death Valley to Mexico City. It doesn't change when you are fatigued. It doesn't change whether you are playing for a Pepsi or your life. It's always the same. At least on this planet.

My rational goes like this. I will let gravity determine the speed of my backswing and I will synchronize my left hand to my right as I toss the ball. Therefore, gravity is determining the speed of my toss and that should certainly lead to a higher level of consistency. The repeatability of this speed is comforting to the body. It says "Oh, I remember this motion. We've done this before; in fact, we've done exactly this before exactly like this; I'm sure we can do it again."

So if someone comes to me to learn to serve, I use this model to build their motion and I have a series of progressions that help them through the various stages of development of their service motions and I know as they go through these stages they will eventually put together an effective serve. (I will try to put up some videos soon that show a three to four year progression some of my students have gone through as they build their serves with these drills.)

On the other hand, if someone already has a service motion, I have to be careful. Before I take their motion apart and leave them naked and helpless as they try to learn a whole new motion, I will try to work with their motion and incorporate some of my principles into their own creation. Usually, I can find a "workaround" that enables them to improve within the framework they have already established.

There are two types of established serves that I will take through a complete change: the obvious one is the player whose serve really doesn't work and who has nothing to lose by giving up their old serve. Unfortunately, my being convinced of this is not enough; the student has to be the one who comes to that realization. They also have to have enough trust in me to stick with what I am asking them to do because it will be painful and frustrating. Those old habits do not go away easily and they will raise their ugly heads at every opportunity.

The second kind of established serve I will change, is when the player comes to me and says I really want to change my serve and is not put off by the fact I lay on them that they will have to hit at least 10,000 practice serves in a three month period before the serve even begins to be useable in competition. It will still take a couple of years to fully learn and more than that to master, but without that initial immersion in focused practice, they will never break their old habits. (The fact that there is some finite number that will enable them to build new better habits makes this infinitely easier than learning strokes you have to hit when the ball does not start out in your hand.)

Ed Weiss and I are working on articles that go into all of this in a little more detail, but let me point out two things:

First of all, whatever motion you use, you must have good rhythm or you will not have any consistency to your toss and therefore to your serve. I prefer to tie that rhythm to the free gravity drop of the racket and in those glorious "pre-McEnroe" eras, the majority of good serves were constructed in a similar fashion. Now whether you use gravity or not, and today it is pretty rare, the lynchpin that holds the service motion together is the weight-transfer/rock. Back to front, Front to Back to Front, whatever...it must absolutely synchronize with the toss of the ball to have consistency under pressure, fatigue or environmental stress (wind).

So I make my students learn to "Toss-and-Catch". My argument is that if you can't get the ball to go up and come down in the right place when you only have to catch it, how can you expect to be able to toss it when you are going to have to hit it. So I have my students toss-and-catch and then "rewind" the motion back to the beginning. They should be able to do this in perfect, repeatable rhythm. So ideally they can take two balls and get 4 tosses and 2 hits without a hitch in a rhythm that is metronomic. Admittedly, they are not firing their legs up into the ball and meeting the ball 4 feet into the court as they eventually might. But if they can't walk, they shouldn't be able to run...or should I say they shouldn't be surprised if they fall down a lot when they try to run!

The second thing I want to say in light of Don_Budge's post above about getting the toss to the right place:

Toss it...See it...Hit what you see!

Tilden may have suggested tossing the ball into your service motion, but I think this is sheer folly. To hit the serve with timing, you have to toss the ball into an area where you can bring that last tenth of a second snap up to the ball you see and you want to hit it with your body fully extended. If you can hit the ball in the tenth of a second after it peaks, it will effectively be stationary in the air having dropped less than 2 inches. If you consider the last 6 inches up to the peak and down from it (about .4 sec) then you have almost a .3 sec window when you want to be in position to be able to strike up at the ball (that last .1 sec on acceleration to contact).

But don't get the idea that you will throw the ball into a churning "electric fan of activity" that is the service motion or my Fig 8 drill. Toss it - See it (and move your racket into position for the final explosion of power) - Hit it.

so much for tonight's ode to insomnia,
goodnight,
don

[tennis_chiro]

Technically, you are correct!

don
thanks for posting the videos. its much clearer now
one question being alittle technical
when you are holding your elbow and the racquet goes from pointing to your right then flips and points to your left isnt that pronation not internal rotation??
i always thought internal rotation was from the shoulder turning the UPPER arm
in your example with your starting position your hand is at 12 oclock
internal rotation would move your hand towards 9 oclock counterclockwise
BUT the racquets orientation to your forearm would not change.
icbw

You are right, Larry, that there is some pronation involved here. If I was truly doing isolated internal shoulder rotation or trying to demonstrate it, my upper arm would be in a vertical plane with my elbow next to my body and the racket face would be maintained in a vertical orientation through the entire motion I am demonstrating there. But in the actual swing, the elbow joint is straightening out as the arm extends the racket up to the ball; there is a lot going on. The pronation is not really a motor unit developing power for the serve according to Brian Gordon's article, but the wrist and forearm do work to align the racket face correctly for impact. As you can see in my little video, as the arm internally rotates (and then counter rotates/externally rotates back to the beginning of the motion) faster and faster, you end up with more and more pronation at the end of the motion as the racket head points down more and more to the ground). The racket face moves from 3 o'clock to 9 o'clock and back again. As it goes faster in my little drill, it is more like 4:30 to 7:30 and back, etc. In my demo, the upper arm is actually doing real internal rotation from 3 o'clock to 9'oclock and externally rotating back, but the hinge at the elbow translates this into a different kind of motion at the racket face, almost like a ujoint in the axle.

I'm not as worried here about identifying which parts of this motion are true internal rotation and which parts are something else (pronation) as much as I am concerned about creating a model that enables you to feel a little of what happens when a player swings the racket through an effective service motion. The biomechanists will undoubtedly take apart everything we might say here in the forum, but our revenge is to actually take something away that enables you to make a better pass at the ball!

don

[don_budge]

One more thing..."it"

So there is always one more thing. After the student has mastered his "figure eights" and developed a gravity based and frictionless swing and the wrist is behaving itself...the whole thing is dependent on one more thing. Putting the ball in the path of the traveling racquet head. This can be very disruptive to the whole process.

There is basically one point in time and space where it all collides simultaneously, and perfectly...where the grip, the motion and all of the generated energy meet the ball. Any deviation from this one point in time and space will produce less than "perfect" shots as energy and potential energy will be wasted or erratic.

I call this point "it". Musicians get it...the whole craft depends upon it. Golfers get it. Tennis players get it. Great oraters get it. Anybody who successfully and repeatedly is accomplished in anything in any walk of life gets it. It's too bad more people don't get it...have you ever known anybody who just doesn't get it. But...it is not so easy as that when you are trying to deliver the ball to that one point in time and space in order to put the ball right where the ball should be, and when the ball should be there. When and where...time and space.

As tennis players, this in the end, is the object of our craft also...we seek to find that one point in time and space where everything is perfect. This relates to our serves, our groundstrokes, to those of us hitting the ball in the air still it relates to our volleys. It relates to every single type of shot under the sun. The quest as it were, is to get the grip right, get the feet, body and racquet into position, and then move all the responsible parts to get the racquet head to meet the ball the way we intend it to when we attempt any particular shot. The ultimate challenge for a human being is to have that kind of control over ones self to master such an endeavor. This is why golf and tennis are God's gift to humanity in terms of at recreation...possibly even more significant than that. There are physics, in a "perfect" world and there are the metaphysics in the real world as we know it. Rod Cross is great but he has left a huge variable out of the equation while focusing on some others. But don't get me wrong, he is fine in a certain sphere of influence, I think.

Perhaps a new thread...and a couple of more videos from Coach Don on the toss...in order to assist the student to find "it". Excellent job, Coach...btw.

[don_budge]

All we need to do is change the frustrating...to fascinating...Part 2

And this was the follow up...I think I am still talking about physics here.

All we need to do is change the frustrating...to fascinating

I believe that the keys to your service issues can be found in frame #1, frame #2 and frame #3. This setup position in frame #1 will certainly get you off to a poor start in your swing and if you start the swing poorly what are the chances of you finishing it well? In frame #2 you can see how quickly you have jerked your racquet back into position and since you were so quick you have prematurely quit swinging backwards...you have not completed your backswing. The problem is now in full view in frame #3 as here you are waiting in this position instead of arriving at the point where the roller coaster car (your racquet's head) has reached the top of the mountain and is ready to fall behind your back at free fall speed...to initiate the loop in your swing behind you. It’s impossible to arrive at the “pro drop” properly unless you allow your racquet to fall, without hurrying things. It looks like you have tied yourself up and are preparing a rather wild and hurried swing, which is more like a hit than a swing at this point, at the ball...btw, where is the ball?

In frames #4 and beyond...you demonstrate that you have practiced a lot or have been playing a long time because you are making quite a nice swing at the ball and appear to be in pretty good control and in balance. The key word here is “appear” because the problem will magnify itself when you are nervous, when it is windy, when the sun is in your eyes or any other little thing that distracts you. You probably do not have a great deal of versatility in your serve because all of your concentration is focused on getting the service in play. Even some pretty Swiss lady who happens to be watching you play may get you just a little too excited to hold your rhythm. If I know that some pretty woman is watching me serve, I slow my backswing even more...give her the full show, you see. My serve tends to get even better under pressure...because of the slower backswing.

But if you turn over the controls of your service to gravity in terms of the speed and the track of your backswing...you can hold the rhythm under any conditions...even when the nerves are in play, like for instance, when you are serving out the set. Ever notice how difficult that tends to become? Trying to get the horse in the barn...you have got to take your time and have an enormous amount of patience and control. You cannot trust your emotions, your wrist or anything for that matter, the only thing that you can truly trust is the knowledge and the confidence that nothing can go wrong...because you have a perfect swing and beautiful rhythm, because your mechanics are based solely on the law of gravity. If you miss the first serve you can swing even harder with more spin at the second because you know...what are the chances of missing two in a row? Practically zero. Some days second serves can turn into a real adventure can't they? And why? It's because of the doubts...that faulty rhythm and mechanics can produce.

I watched The Masters golf tournament this weekend...I think I enjoy watching golf more on TV than tennis, I don’t know why I tend to find tennis boring to watch...maybe it is the lack of style nowadays. Perhaps it's the beautiful rhythm of the swings that holds my attention...they mesmerize me. But one thing about the golfers...every single one of them is virtually identical in their backswings. Why is that? That is because the ball is teed up or lying still and they have the time to make the perfect backswing. You can see that none of them are in any particular hurry to finish their backswing because they are gathering all of the resources of power and control that they possess to use the force of gravity together with the motion of their arms and body to control the club head. They get themselves into perfect position at the top of their swing and without hurrying things they allow gravity to initiate their downwards motion to deliver such a sweet and crisp contact at the bottom of their swing on the ball.

Since we are serving...it is the only time in tennis that we have total control of the ball, we can tee it up with our toss, maybe we should learn a bit from the golfers and take our time in the backswing so that we can get ourselves (mind, body and soul) under control to make the most powerful, efficient, controlled yet effortless swing that we can. Sort of like Richard Gonzales...but within our limitations, Phil. Just like the golfer we are trying to gather everything in our power to make the ultimate contact with the racquet head on and through the ball...but instead of the swing climaxing at the bottom of the swing as a golfer does, the serve is climaxing at the top of our swing. Isn't that rather interesting?

I can see that you have plenty of ability and that you are in really good condition...in three or four hours I believe I could get all of your resources together, in harmony with the universe, to make a gravity based swing at the ball. Depending upon your flexibility...to change.

And to make a long story short...incorporate Don's figure 8´s. I remember doing those exercises religiously before practicing my serve back in the old days.

[don_budge]

Roller Coaster of Love...Part 1

Then I wrote this in April for Phil's "frustrating" thread...I deleted this one as well. Stupid me, I didn't realize that this was somehow related to Rod Cross's physics lesson on...what is it he is talking about anyways? I remember talking to my college roommate and doubles partner and backcourt mate on the basketball court, many years ago, 1076 I believe it was...he was a Chemical Engineering major, I said to him..."you know Jim, a tennis match is really one big physics problem and equation, I wonder if you could take an entire tennis match and express it as an equation in terms of force, vectors, with specific quantification." He looked up at me from his studies and said, "That's an interesting thought." I never did follow up on my thought. He went on studying and I went out to practice.


Roller Coaster of Love...remember that tune?


Phil...I have been studying your video over the last couple of weeks and gleaned everything I can from it. The one view has its limitations and the still sequence of your serve adds some insight as well. The only sure way to do this thing is in person...care to fly over to Sweden for a couple of lessons. Just kidding.


The service motion is a bit complex and it involves quite a bit of motion from all of the different parts of the body...so we try to simplify things by creating a model we can relate it to in simple terms. The model that I use is the “berg och dallbana” which translates literally into English from Swedish as the “mountain and valley course”...but it means “roller coaster”. A roller coaster is an amusement park ride that is perfectly designed using the law of gravity. The design is so perfect that the ride feels that it is wildly out of control and traveling at incredible speed...but is so amazingly in control that the owners of such rides are betting everything they have that the ride will not spin out of control and kill a bunch of innocent people on a Saturday afternoon. This is the safe and secure principle we shall attempt to modify your backswing to in order to get you going forward into the “hit” with perfect and effortless energy. We are going to be using gravity as our main source of energy...to create a perfect, yet simple motion...a roller coaster of a serve.


Here’s the thing, Phil...about the set up and backswing. This is a real challenge without having you in front of me to study for a while. To set you up to begin your motion I would like you to create a line directly at your target with the toes of your two feet which are approximately shoulder width apart. Imagine this line going forwards towards your target and all the way back of you to the fence. This line will serve as our “track” for the backswing. I would like to see you bent slightly at the waist so that your arm can “swing” from your shoulder without your body getting in the way. Finally, I would like you to line your racquet up to your target as well, on the same line as the line that your feet created. Point your racquet at the target and hold it about waist high supported by your left hand. Weight distributed from between 60/40 to 70/30 from the front foot to the back. Great...now we have you lined up, and taking aim.

Here we go...hold on to your hat! One thing that we must clarify before we go into any kind of explanation about the motion is the pressure of your grip. Sam Snead referred to the grip on his golf club as holding it with only so much pressure as you would hold a live bird. We only hold on with our hand tight enough to not let go of the racquet. We maintain only enough pressure in the entire arm, forearm and wrist to swing the arm and racquet back into position in one piece without disturbing the exact position that it is in at the setup position. We must eliminate all sources of tension and resistance when we are attempting to use pure gravity to dictate our motion. From this relaxed and confident position at setup we need only to release the racquet with our left hand that is supporting it, and allow the weight of the racquet head to merely fall upon the line of the track all the way back to the fence until it reaches a position at the top of the hill. From the starting position, the roller coaster car begins its decent down the first hill until it reaches the bottom where it will begin its assent slowly up the second hill all the way to the top. Remember the track is along the line that we created with our feet towards our target and it extends all the way back. Keep the racquet on this track. By allowing gravity to dictate the direction and speed of our backswing we will create the position back in our swing where the laws of gravity make the most sense and the least number of things can go wrong. In fact nothing can go wrong...just like the roller coaster. By dropping the racquet head and allowing the weight of it to travel smoothly in front of you and only using the energy of your weight transferring to the back foot by slowly turning your shoulders and allowing your arm to freely swing back into position, we create a position where the racquet will naturally drop behind us at free fall speed into what you are referring to the “pro drop” position.

Now this is where things get a bit interesting...and exciting. Thinking about this point of the motion where the racquet makes a loop starting at free fall speed, behind our backs and how it relates to a roller coaster, we can imagine where the cars of the ride go into a loop and the riders are actually upside down on the track with only gravity to keep them glued to the track. This is where the riders of the roller coaster are screaming at the top of their lungs and their faces are contorted with the g-force that is plastering the tissue of their faces to their skulls. It’s in the loop, baby! This is where the drive of the legs, the turning back of the shoulders and the thrusting or throwing motion of the racquet combine to exponentially create an incredible amount of speed with very little effort. You can imagine that the line a piece of pencil would draw if it was attached to the tip of the racquet...this is your track for the roller coaster of your serve.

The backswing is where I observe the source of your issues. It looks to me that if we can get you into position you can make the move forward if you can maintain a loose grip on the racquet and the relaxation in your arm to create a whip like sensation. (insert post #32 at this point for the action of the wrist)


Just one more thing...it looks to me in frame #3 you have tossed the ball right out of the picture and in frame #4 it is returning to earth. I think your toss is a bit high...which would lead us to the next lesson, how and where to toss the ball.


A description of the Pancho Gonzales serve…

The Gonzales service is a natural action that epitomizes grace, power, control and placement. The top players sigh when they see the smooth, easy action. There is no trace of a hitch and no unnecessary movements. I have never seen a serve so beautifully executed. The toss is no higher than it has to be and it is timed so that he is fully stretched when he hits it. The backswing is continuous and the motion of the backswing blends into the hit and continues into the follow-through without a pause..

Like you...I am a huge admirer of the Gonzales serve...and he obviously knew his "metaphysics".

[don_budge]

Pronation and Use of the Wrist When Serving...

I wrote this in March in response to "erbr" and deleted it after posting it for some time...not nearly as sophisticated as Rod Cross, but I understand the math. Normally I operate on the KISS (Keep It Simple Stupid) principle with my students and myself as well.

The Wrist is a Hinge

Am I the only person who considers pronation as a natural biomechanical occurrence?-erbr

Knowledgable tennis players and golfers all over the world agree with you. When teaching the serve I sometimes make a bit of an oblique reference to the serve being similar to an upside down golf swing. Instead of teeing it up on the ground, we attempt to tee it up in the air. To begin with some of the similarities are the take away, the backswing, the transition between backswing to forward motion and the "release" of the wrist(s) which deliver the racquet or club to the ball...it even helps to "waggle" the racquet a bit in the preserve routine. The action of the wrist(s) is perhaps the most fundamentally important aspect of swinging a tennis racquet or a golf club (Ben Hogan certainly agrees with you)...or to swing anything else for that matter. This goes for all shots...long or short, fast or slow...not just the serve. It is also perhaps the most difficult aspect of swinging to convince a tennis or golf student of...it is a matter of swinging, not hitting. Getting too "wristy" even with short putts is the kiss of death, but that being said...you still must swing the putter.

I describe the function of the wrist...or "handled" as it is called in Swedish...as that of the hinge on a door. One never has to consciously think about applying the wrist in the swing of the racquet or the club, but you must let it do what it most naturally wants to do...and that is to swing smoothly with all of the centrifugal energy that the mind/head (the idea behind the shot intended to play), the feet and legs, the hips and body, the shoulders and finally the arm have created. The action of the wrist is a product of all of this and it's job is to transfer all of that action into the face of the racquet. It's really such a simple thing...ha ha. But it's best not to talk too much about it...or to think too much about it either, for that matter. Better to concentrate on footwork and getting into position and just letting "the thing" happen.

Once the wrist(s) take over...delivering the payload feels a bit like "slamming the door".

Everyone always talks about the thumb being such an important digit for homo sapiens. But the wrist for tennis players...and for golfers, is the joint that makes it all possible. Superb question erbr...and I agree with you.

[llll]

don
thanks for posting the videos. its much clearer now
one question being alittle technical
when you are holding your elbow and the racquet goes from pointing to your right then flips and points to your left isnt that pronation not internal rotation??
i always thought internal rotation was from the shoulder turning the UPPER arm
in your example with your starting position your hand is at 12 oclock
internal rotation would move your hand towards 9 oclock counterclockwise
BUT the racquets orientation to your forearm would not change.
icbw

[gzhpcu]

Good stuff don... Worthy of an article in tennisplayer...

[tennis_chiro]

I hope this helps

im sorry but i get lost in your description
could you post a youtube video???
pretty please
larry

Notes on Complete Snap Sequence

I couldn't get youtube to release my 7 minute video from processing (maybe by the time I wake up in the morning), so I broke it into 4 mpeg4 parts (which is their preferred format it seems.)

First part:

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

About a minute and four seconds in I say, "My elbow is not moving". I should have said as the upper arm rotates, my elbow is inactive in almost the same place, but it is being rotated by the upper arm.

Second part:

http://www.youtube.com/watch?v=zrxmoQ4HhRA

In the "SnapUp" drill, I am pointing out the lack of internal rotation when you use the "frying pan" grip instead of a continental.

Third part:

http://www.youtube.com/watch?v=rzUB5wjEIzQ

In the trophy position drill, it doesn't matter if you take the racket there like Don demonstrates in the video with a full backswing or you take it up in an abbreviated manner like Gonzales, you still have to get to that "trophy" position. If you were doing a continuous motion without a pause your weight would be going forward as you tossed the ball and brought the racket up simultaneously.

Part 4:

http://www.youtube.com/watch?v=2NCiPeTzdw4

But in the "hiccup", we pause to emphasize a good "trophy" position; now since you brought your weight forward as you brought the racket up (probably) we have already used the weight transfer and don't have the rock to hold everything together as we toss the ball. So, we reload the weight while the arm waits in the trophy position and keep it there until you complete the toss, then drop the racket down and hit up. This is an artificial rhythm, but it is a way to break it down and keep a rhythm where the weight transfer/rock is integrated with the toss. This is a necessity. As strange as it looks at first, most students take to this very quickly and serve quite well with the "hiccup" as an intermediate step until they have a little more control and can do parts 1 and 3 (count 1,2,3,4) together, eliminating step 2. They can even do a practice toss and catch in the hiccup to get the feeling of where to hit the ball without actually hitting it. They can toss it and catch it a few times, with the racket waiting in the trophy position and in a metronomic rhythm, until they are ready to go up and hit it. I will tell them to toss and catch repeatedly until I give them the clearance to go ahead and hit the ball without any pause from the toss and catch. Rhythm is the key to consistency. The rock/weight transfer is the lynch pin that holds everything together. It has to be synchronized to the toss or the serve will never be consistent.

And I threw in a few shots of the snap and my serve when I could still hit it at least a little bit so you could see how this is supposed to work.
Part 5:

http://www.youtube.com/watch?v=7Y6Tu5HxU_o

I'll probably have to figure out how to post the actual clip on ImageShack so that it can be accessed framebyframe.

This presentation goes right along with the post I originally put up for Bottle. I hope it helps. It was a whole lot tougher than I thought to put it together and put it up!

don
And below is most of the text of the original post for Bottle!


So there are a few steps to this drill.

First, you have to understand what my "Figure 8 drill" is. I think you are familiar with this but other members of the forum might not be. Just pretend you are making continuous swings standing in an alleyway extending to the target and there are 30 foot high glass walls on this approximately 2 foot wide alley. Here's a clip of the figure 8 drill.

http://www.youtube.com/watch?v=gaS-qtQWym4&NR=1

Unfortunately, I didn't have audio (I thought I did) when I made this recording. I need to update it and put some more videos up, but haven't done it yet. You could use this in conjunction with the positions demonstrated by Kerry Mitchell in his first service article

http://www.tennisplayer.net/members/..._serve_part_1/

Now, we get to the specifics of generating your increased racket head speed.
We start with internal rotation.
Stand facing the net with your upper arm next to your body and your forearm perpendicular with the racket shaft actually parallel to the baseline, the palm up, racket face horizontal and off to the right of your body. (for righties. Are you a lefty, Bottle? I mean left handed.) You can even rest your right elbow in your left hand.
Without taking the elbow out of your left hand, rotate your forearm to the left so the racket face moves 180 degrees to where it is face down, palm down, but the face again horizontal, but on the opposite side of your body.
Swing it back to the start.
Now go back and forth as quick as you can without moving your right elbow out of your left hand.
Optionally, you can go one stage further with this particular step by swinging the racket so far to the left that the face goes past horizontal and the shaft even begins to point down as it goes more than 180 degrees. At this point, you would be adding a little pronation and your elbow would pull out of your left hand.
In any case, do this back and forth as fast as you can. Feel the internal rotation and how the racket head goes past the wrist.

Now you try to take this feeling into doing the aforementioned Figure 8's. Try to "whistle" the racket at its highest point in the swing, just at or after contact. Next try it actually hitting the ball.

Want more?

Stand with a slightly open stance at about 45 degrees to the baseline (because this is an abbreviated motion and you won't have the benefit of a full swing to turn the hips and shoulders forward from the normal starting position).

Position yourself so the shoulders are actually parallel to the baseline (or even perpendicular to the intended path of the ball).
First put the racket face up to the contact point. (Remember the racket is not straight up. For a righty, the forearm and the racket shaft form a 10 to 20 degree angle at contact. Just guessing on those numbers. Check with John and Brian's data.)
From the contact point, while leaving the elbow exactly where it is pull the racket head back down as you externally rotate as you reverse the internal rotation that took the racket up to the ball.
Now, while leaving the elbow where it is, swing the racket head up to the contact point and past to the "Sampras racket head down" point. Now swing the racket back and forth along this path. It's kind of like what we were doing in our first exercise here, but a little different.

Note: it is important that at the starting point of this motion the butt of the racket is pointed like a flashlight at the ball and also in the direction of the target. Most people have to be corrected from a position where they have the shaft of the racket pointed too far to the right and they are unable to generate sufficient force in this swing in the direction of the target to get the ball over the net.

Once you get a little feel for it, starting from that point with the elbow up in front of you, toss and "tap" the ball over the net. Range of motion and a "clean" contact is the goal here, not speed.

When you feel you can do that a little bit, try to incorporate the feeling into the figure 8 drill. See if you can get a little more "whistle". But don't worry too much about speed in the actual hit just yet. "Hard" is your enemy right now. "Relaxed" is your friend.

Now we go to the next step. Maintaining the same stance position you had in the last drill (about 45 degrees open), go to the "trophy" position. Now see if you can toss the ball (always transfer your weight forward as you toss the ball; you don't get to use your normal backswing, but you can still have a little rhythm with a rock or just a back to front shift as you toss the ball) and then do the last drill from "trophy" position and still finish with the right elbow up and the "Sampras racket head down" ending…literally. Of course, that means you can't swing too fast; but you can still propel the ball a little faster than we did in the initial version of this drill.

Now if you can feel this, you can try and put that feeling into the Figure 8 and go for even more "whistle".

Bottle, all this is pretty removed from what Rod Cross was pointing out. But one key to doing this drill is that the wrist must be in control, that it is it must have the racket handle snug in the hand and against the heel of the hand; at the same time, the wrist must be completely relaxed and just acting as a hinge to allow this full range of motion. Certainly, there will be some wrist flexion and ulnar deviation involved as you move the racket head up to the ball, but the true primary forces are going to be coming from other elements.

And finally, if you can put all this together and feel a little more racket head speed and get the "whistle" to happen at the right time (up through impact and just beyond), you will be forced to exert significant centripetal forces to overcome the momentum and forces of the racket as it swings up to the ball; thereby you will have to do what Rod Cross is describing in his article. But I don't think you will be able to accomplish that if you try to "exert centripetal force on the handle of the racket with a vector at the heel of your hand counter to the vector exerted at the first knuckle and the fingers". Not going to happen!

[llll]

Great, but what's the matter with the Don videos which are already up?

he goes into another discussion which a video would clear uo.
at least for dense people like me that are highly motivated

[julian1]

Vertical velocity is zero

Cross made a distinction in parts of his paper about the forehand and the serve. In the part I was referring to in what you exerted, Cross was talking about the forehand and that was what I was referring to as well. My concern was with the vertical velocity in the wiper.

don

1.he assumes no topspin for forehand.
2.he assumes no u shape of forehand

He may try to do some generalizations of his paper.
I believe that an easiest one is to assume three segments of an arm as
opposite of two.
I do NOT think that generalizing from two dimensions to three dimensions
is a piece of cake but I was wrong too many times before.
Probably a case of an arm locked at a right angle with a racket
is THE EASIEST ONE for three dimensions..
However I do NOT think "a right angle" above is a very realistic assumptions.
I do NOT know what is done in three dimensions for golf and baseball.

PS An interesting subject to talk is a fact that he has two different models
of forehand.
I will try to discuss it soon
PS there was an attempt to talk about his paper at Tennis Warehouse
but a discussion got diverged to unrelated topics.
Some comments posted there are incorrect

http://tt.tennis-warehouse.com/showthread.php?t=384083

[tennis_chiro]

Distinction

Don,
your quote below.
Do you talk about forehand or serve ?
If forehand a following quote from a paper by Rod of American Journal of Physics would apply:
"A forehand in tennis is often struck with topspin by swinging the racket upward as well as forward.We will ignore vertical motion of the racket and assume that forearm and the racket swing in a horizontal plane"
----> your quote
I still have a little question in that while this measures angular velocity, the question is in what plain is that taking place. If it is in a plain parallel to the upward movement of the racket towards the ball, we could calculate by its' angle how much the arm is moving upward at contact (which I believe would not be zero). If it is measured in the horizontal plane, then there is no accounting for the upward movement of the arm and that is a little disingenuous, because the arm is really still moving pretty fast. It may be true from a physics point of view that the upward movement in the z plane should not contribute to linear velocity in the x and y planes, but let's let the data show that.

Cross made a distinction in parts of his paper about the forehand and the serve. In the part I was referring to in what you exerted, Cross was talking about the forehand and that was what I was referring to as well. My concern was with the vertical velocity in the wiper.

don

[julian1]

Plane

Don,
your quote below.
Do you talk about forehand or serve ?
If forehand a following quote from a paper by Rod of American Journal of Physics would apply:
"A forehand in tennis is often struck with topspin by swinging the racket upward as well as forward.We will ignore vertical motion of the racket and assume that forearm and the racket swing in a horizontal plane"
----> your quote
I still have a little question in that while this measures angular velocity, the question is in what plain is that taking place. If it is in a plain parallel to the upward movement of the racket towards the ball, we could calculate by its' angle how much the arm is moving upward at contact (which I believe would not be zero). If it is measured in the horizontal plane, then there is no accounting for the upward movement of the arm and that is a little disingenuous, because the arm is really still moving pretty fast. It may be true from a physics point of view that the upward movement in the z plane should not contribute to linear velocity in the x and y planes, but let's let the data show that.

[bottle]

~

Great, but what's the matter with the Don videos which are already up?