John's Classic Article about the PinPoint vs Platform

[uspta990770809]

In rereading this article, a couple of points jump out at me.

First of all, Rusedski had the fastest serve at the time (at 149 mph), pinpoint or platform, and the article makes the point he had the least knee bend of top servers.

Second, John is very clear the difference in servers with pinpoint or platform stances is very small vis-a-vis actual top speeds.

I continue to feel kids make too much of an effort to throw themselves into the court with a deep knee bend and upward explosion, when they really haven't mastered a simple good snap which involves all the elements of the kinetic chain from bottom up. Even if you can do everything right, the deep knee bend advocated in many quarters and seen by many top pros adds only a few mph while significantly negatively impacting first serve percentages and accuracy (which is not measured that I know of). You can check Brian Gordon's articles for a clearer outline of how much the big push from the platform stance (thought to be the stronger of the two stances in this regard) can contribute to ultimate service velocity. But I don't want a student to even move one foot across the line into the court until he/she can show me that he can hit 5 serves in a row into the box with at least some regularity without moving his/her feet.

It is necessary to get that kind of control of the motion before you start taking off like John Isner. No question being an additional foot off the ground when he contacts the serve helps Isner improve his already enviable contact position, but if he didn't have a decent snap (he has a great one) and good use of the kinetic chain, it wouldn't matter.

I'm all for maximizing the serve. After all the ball is in the server's hand. But most of the "advanced" juniors that I see, have little or no ability to control their body and balance when they go to hit a serve. Each and every toss is an "adventure". You can't learn to drive a car on the "autobahn". You need to start in the parking lot and work up before you hit 4th gear. They see all the pros using their legs and they don't know that those pros perfected the basic motion and got control of it before they started to improve it and get a few additional mph by hurling themselves upward. This confusion is making it harder for millions of kids to learn a good basic service motion and someday have a chance to be able to hurl themselves into space and get some real benefit from some upward lift, either from a platform or a pinpoint stance.

Comments?

[gzhpcu]

Agree. That is why I like to look at the great Pancho Gonzalez serve as a model. During his era, you were not allowed to jump, and he has a really great motion as can be seen in the Tour strokes section.

[johnyandell]

I would have to agree the racket path is the critical prerequisite for anything else!

[CraigC]

Fundamentals vs. Flair

On a serve, it seems like the repetitive ballistic move upward would fatigue a player. So, if it is true that a deep knee bend adds very little to a serve's velocity, why do the players do it?

This actually leads to my real question which is: Are many of the moves, in the service motion, performed to take the strain off the shoulder joint, more so than to aid velocity. I can stand relatively still, facing almost parallel to the baseline, and snap off a 110mph using just my shoulder and elbow joints. After about 5 of them, my shoulder would feel like it's been attacked by Dexter (over-indulgent serial killer reference). Aside from the obvious footwork maneuvers, are there specific movements athletes use in stroke production in order to preserve the body, more so than to accentuate power and control? And if so, can you or Brian provide a little detail about them?

I contend that much of tennis is about flair, and very few things are fundamental. So few players hit the ball the same way these days, but as you have always argued, the commonalities in the strokes are almost always there. So do the "flair" portions indicate an athlete is using their own body's leverage and individual strengths to accommodate their fast swings? And is this "flair" a result of players protecting their bodies from injury? Ex. Rafa's reverse forehand finish is extreme, but since he is creating excessive spin with his stroke, does that finish protect his shoulder from incurring the stress of the vertical movement in the stroke.
CC

[johnyandell]

Think you can feel what that knee bend does to the serve. And yeah the upper body stays more relaxed in my opinion. The biomech numbers i don't know about but feel this is one of those few commonalities of which you speak.

[uspta146749877]

Knee bend and ground reaction

On a serve, it seems like the repetitive ballistic move upward would fatigue a player. So, if it is true that a deep knee bend adds very little to a serve's velocity, why do the players do it?

This actually leads to my real question which is: Are many of the moves, in the service motion, performed to take the strain off the shoulder joint, more so than to aid velocity. I can stand relatively still, facing almost parallel to the baseline, and snap off a 110mph using just my shoulder and elbow joints. After about 5 of them, my shoulder would feel like it's been attacked by Dexter (over-indulgent serial killer reference). Aside from the obvious footwork maneuvers, are there specific movements athletes use in stroke production in order to preserve the body, more so than to accentuate power and control? And if so, can you or Brian provide a little detail about them?

I contend that much of tennis is about flair, and very few things are fundamental. So few players hit the ball the same way these days, but as you have always argued, the commonalities in the strokes are almost always there. So do the "flair" portions indicate an athlete is using their own body's leverage and individual strengths to accommodate their fast swings? And is this "flair" a result of players protecting their bodies from injury? Ex. Rafa's reverse forehand finish is extreme, but since he is creating excessive spin with his stroke, does that finish protect his shoulder from incurring the stress of the vertical movement in the stroke.
CC

Dear Mr CraigC,
A knee bend activates ground reaction forces
respectfully yours,
julian
PS A classic reference on this subject is
B.Elliot Biomechanics of the serve in tennis:a biomechanical
Perspective.Sports Medicine,6,285-294
A more accessible source is "Biomechanical Principles of Tennis
Technique" by Duane Knudson Page 51

[oliensis]

I would beg to differ on the subject of knee-bend and accuracy...or at least the subject of accuracy vis-a-vis getting serves into the service box.

In my humble experience playing (4.5 level) and teaching my daughter to serve (she's 15), while it's possible to serve with high mph without much knee bend, the upward thrust from a deep knee bend (think Agassi) is extremely constructive in terms of ending up coming over the ball AS you're hitting through it...thereby adding topspin sufficient to bring many balls down into the service box with an arm and shoulder action intended to create an essentially "flat-ish" rather than "very spinny" serve.

On a related subject, in my view one of the reasons Federer's forehand has become so much more error-prone is that his "load" is so much less extreme than it used to be. As a consequence (at least in my observation, and I watched him in person, very close-up for an hour on Fri before the Open practicing w/ Monfils on the Armstrong court) when he's a hair late on his setup he ends up slapping the ball a bit.

While the difference between a late, not-much-knee-bend slap and a pure "carve" (with a pure load/explode process) through the ball may be very difficult to measure, the feelings of the 2 are extremely different, and the difference is significant when it comes to the percentage of shots that do not land in the court.

Same for the serve. I can slap it real hard flat-footed. But I bet my service percentage and the amount of spin on the ball at a given MPH will be quite different relative to a serve hit w/ deep load (knee bend).

[oliensis]

To follow up w/ one more thought experiment:

Try throwing a baseball from your knees. See how hard/far you can throw it.
Now try it using a pitcher's windup (http://www.youtube.com/watch?v=wDgMXFBHLP0) and convince yourself that the legs are superfluous.

Sure it makes sense to break down the motion and sometimes just work on upper-body mechanics, but imagine trying to learn to throw a curve without using your legs!

[bigryoung]

I think it would be difficult to have good rhythm without bending the knees. All the while I am getting lower, my racquet is coming up. When my racquet is at its peak I start coming up with my legs and my racquet goes down behind my back. Without bending the knees, one would have to arch their back significantly in order to get the racquet behind it.

[uspta990770809]

Not saying no legs

I'm not advocating that anyone serve like the Dutchman of a few years back (espapes me just now, semifinalist), but the emphasis on deep knee action is misplaced. Players used to "bow" their bodies and legs and then straighten up into full extension. I think Brian Gordon can back me up that the main contribution of leg power is in the rotation forward and that the deep knee bend and upward move only adds a little bit. Perhaps I'm wrong and the only way you can ever learn that extreme move up is to start with it and struggle until you finally get it, but I feel you need to get the full motion under control before you start exploding up with that deep move. I see a lot of kids that jump great, but their overall action is so poor that the racket is actually coming down to the ball by the time they meet it. In fact, serving from the knees was one of the classic Van der Meer drills for learning to hit up at the ball.

As for the strain on the back (and I'm a chiropractor now), I had a big serve (12 aces against Hewitt&McMillan in 5 services games in Munich WCT'75)and a big "bow", but very little knee bend and it probably has a lot to do with the fact that I have wafers for discs at L4/L5 and L5/S1 and can't handle any violent moves anymore. (I do wish I had known about chiropractic when I still had a good back!) So I'm pretty sensitive to the idea that you have to flow smoothly up into the service motion. But I really question whether you get more speed from a deep knee bend than you do from a shallower "bow". Look at how far high jumpers bend or how low pro basketball players bend to dunk a ball. The deep leg action is good for massive force, but real power requires speed and I'm not at all sure you get more speed by going down that low. And we need speed to stretch those shoulder muscles as the body goes up while the racket is still dropping to its lowest point in the backswing.

Time for the biomechanists to chime in, please...
don

[uspta2712824457]

The Dutchman with no legs?

Don,

I love your insights. Thanks for contributing.
The Dutchman you speak of is none other than Sjeng Schalken. You are correct. he made it to the Semifinals of the US Open back in 2002.

Here's a video of Schalken playing Muster

http://www.youtube.com/watch?v=e-8On...eature=related

Here are his groundstrokes.

http://www.youtube.com/watch?v=_jMG0...ext=1&index=13

I love it! LOL

Kyle LaCroix