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Old 10-29-2012, 07:47 PM   #544
mntlblok
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Quote:
Originally Posted by sureshs View Post

Read the expert Rod Cross here and learn the facts before arguing:

http://www.racquetsportsindustry.com..._tennis_f.html
Warning: This is way too long. Don't start it if yer concerned about having yer eyes glaze over. . .

Had never bothered to look into MTM before, but just (finally) made it all the way through this thread. Glad I did. There's lots of interesting stuff, some pretty intelligent folks involved in it, and, believe it or not, I thought more reasonable discussion than what is often seen in online forums.

I *do* think that I've picked up a few "errors" or at least some things that aren't as clear as they might be, and thought that I'd throw in what I think might be some "clarifications", and maybe even a new idea (or, at least, opinion) or two.

The above article by Rod Cross didn't say anything about the "sweet spot" nor its size. Rather, it explained that the spin window (don't think he used that term in the article) is enough larger with a ten inch wide racket than a wooden, nine inch wide racket so that one wouldn't routinely frame the ball with the use of the swing paths, speeds, and face angles that can be used with the modern, lighter materials. He notes in the article
"Give a 9-inch graphite racquet to a player today and the result would be some serious clipping of the frame every few shots. . ."

Toly was exactly right about the perspective from which "sidespin" should be observed and described when speaking of "clockwise-ness". The axis for sidespin is vertical, so you gotta look at the clock face from either above or below. From above, Rafa's forehand sidespin - at least on the "high" ball in the thread, would be counterclockwise.

When Rafa "hooks" one, which I'm pretty certain is only going to happen off a "low" ball, the sidespin would be clockwise.

I don't know what all is actually part of the MTM thing, but the "across" part, as presented in this thread, and what I saw in the video with Mr. Wegner, ain't exactly right. While the the "wiper" follow through does go across, and the "grazing" of the ball by the strings would be (partly) in that direction on a high ball, it *wouldn't* be in that direction on a low ball, but rather, the opposite. That same vertical axis would be spun about in the opposite direction, and the flight of the tennis ball would be seen to curve in the opposite direction.

The cool still photo that Toly posted with Rafa's racket almost vertical was excellent for demonstration of what happens for sidespin on a high ball. I'm betting that a similar photo could be found of Roddick with a near vertical racket, but with the head pointing to the ground, for one of his "hooking" forehands off a low ball. I swear I've seen him "waiting" for a ball to drop low enough so that he could spin it counterclockwise () off his righty low ball.

I've loved all the photos in this thread where many stages of the racket positions have been shown in one shot. I've been wanting to see these "rainbows" of the "before" contact section of the swing for a long time. I remember one from years ago of the "after", and recall practically begging the guy who posted it (maybe even on tennisplayer.net, with "rainbow" in the description).

My current theory about teaching topspin is that you can put these two rainbows together and come sorta close to laying a pain of glass against the ball striking areas of same, and have both the grip and the stringbed lying against it (the pane). For a righty forehand, I tell folks to imagine a large window pane whose bottom edge runs approximately between their feet (which are in a neutral stance, straddling the baseline) and that same bottom edge lies right on top of the baseline, but with the top of that window pane leaning well forward. These edges are both basically perpendicular to the intended target line.

Next, (and I know this is an over-simplification and isn't exactly accurate) I have them have their racket hand *and* the stringbed make that big "rainbow" move - both before and after contact (and during) - whilst keeping those two parts of the racket lying against that window pane (and pretty much facing the target).

So, the first part of this "rainbow" swing along the "window pane" is actually "left-to-right", with the butt of the racket leading the way, with the stringbed lagging well behind. I don't know that it's universal, but I've watched a *lot* of super slo-mo's of pro forehands (both on YouTube *and* on the various online tennis instruction sites *and* on the cool DVD's {were they "CD's" back then?} that I bought from JY years ago) and I've concluded that the stringbed only catches up with the hand (the long axis of the racket becomes parallel to the ground) at about breast height. Below that height, the player's hand is always above the ball at contact. Above that height, the middle of the stringbed is above the player's hand.

Another relationship that changes with location on the "rainbow" is how far the ball is from the player's body. At the extremes of height, both low and high balls, human anatomy dictates that the ball must be closer to the body. (I haven't thought through the ramifications of whether one uses a bent or straight elbow for these balls).

And, since the window pane leans forward, the higher the contact point, the further out in front contact must in order to maximize the "hit". So, a high ball will be contacted both close to the body line and well out in front. A low ball is contacted close(ish) to the body and much less "out front".

It *may* even be that the rainbow "bows over" a bit more near its top, as I've seen stills of pros with some very closed racket faces way out yonder.

Key to keeping both the hand (grip of the racket) and the stringbed lying "flat" on this pane of glass is that the wrist must be "laid back" (extension?). I was very happy to learn of the "double bend" from JY many years ago. I feel that this position is far too often ignored by the teaching pros that I watch giving lessons - at least, as someone in the thread mentioned - to adults.

One of the reasons that I like to use the "pane of glass" concept rather than a "plane" is that I can describe which part of the racket would cause the pane of glass to "break" if the player changes the plane of his stringbed as it comes counterclockwise around this "rainbow" of a "leaning" clock face from something like six o'clock to twelve o'clock.

If the player "loses his layback" or "flexes" his wrist, then the tip of the racket breaks the glass(and he misses the shot wide).

If he "closes" the racket face beyond what his grip has set up (rolling the face in an attempt to "help" with the topspin), then the top edge of the racket breaks the glass (and he misses the shot into the net).

If he "opens" the face in an attempt to "help" the ball over the net, then bottom edge of the racket breaks the glass (and the ball goes long).

Part of my theory is that the longer the racket face is facing the target (on this "window pane plane"), the greater the margin for error is for "timing" the shot, for both direction and trajectory. One of the online instructors tells me that his coach said pretty much the same thing to him decades ago.

My quest to get at the bottom of what makes a topspin forehand work stems from *many* years of hitting an extremely inconsistent one, myself. Many lessons from many different pros failed to nail down the primary problems. It took a visit to Brian Gordon when he had his operation in Cincinnati a number of years ago to start getting it figured out.

Interestingly, getting hooked up to his wires and his (then) magnets (rather than today's infrared cameras) only exposed *part* of the problem - too steep an upward swing path (with the hand), especially on high balls. *But*, a second serious issue only showed up the next day during the "lesson" part of the program when I was trying to clarify something he was telling me and I demonstrated my backswing "loop" in slow mo and he noticed that I was *opening*, rather than "closing" the face, which, it turns out, then cause me all kinds of problems with trying to get back "on plane" for the forward swing.

BTW, I believe I read in another thread recently that Dr. Gordon can't actually "hit" a tennis ball. Fact is, he can knock the **** out of one on an amazingly flat and controlled trajectory. When I last saw him down in Boca Raton, IIRC, he was thinking about starting to enter some age group tournaments (50's?), in spite of his arthritis issues.

(continued in next post)
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