Sampras Serve Racquet Head Speed

[llll]

brian and john. hers my thoughts on the data presented
the serve is one of build up of acceleration. as you proved the acceleration does not happen linearly. like a snowball going down a mountain the rate of acceleration is not constand and faster at the end.
i do beleive the rapid acceleration is from "pronation". if you measure the acceleration from on edge to contact the arm shoulder is internally rotating and pronating.you guys can be more precise of my description. this when you get that last burst of speed.
the elbow and inverted racquet are the result of what came before it. it tells how much or if pronation occurred. the is the end stage of it or the release.
its start of it that is the "cause".
i hope i explained myself and i definitely would like both of your comments. thanks john and brian for another groundbreaking article. larry

[johnyandell]

yeah well that word cause is actually kind a trick phrase in my view. I can't speak for Brian and wouldn't try, but if you look at his article the serve and tennis science, he outlines the contributions.

But is a contribution a "cause"? Note the long debated role of the wrist--that move up to neutral is a huge contributor, but is it a cause? Obviously the the upper arm rotation and the pronation (in the correct biomechanical usage) play a role.

But personally I think it's a mistake to isolate one factor too much as the "cause." For example a pro player I worked with could consistently hit 130mph on the tour radar, but had half the "pronation" (in the layman's sense of the term) of Pete.

Brian's new systems in Florida allow players and coaches to experiment with various technical factors and see the actual effect on racket speed.

I've said it before and I'll say it again, for me, it's about looking at technical positions in the motion--like the drop, like the knee bend, like the turn off the ball, like the ball position at contact, and then seeing how they help a given player. Focusing on one factor or even limiting it to a few may not produce the best result.

[GeoffWilliams]

Just read the Sampras article. I had no idea that was true, and I have been taping Sampras since he beat Lendl in the Philadelphia indoor, in 1989. Of course, the quality is awful, off broadcast vhs.

He really gets under the elbow and snaps his forearm from the elbow, not the wrist, for a longer lever arm. I had no idea the speed differential was that extreme.
I always thought he had the best technique of any person on the serve who ever picked up a stick.
He hunches, he crunches. That bow he produces off his left hip is extreme. His shoulders almost form a 90 degree angle into trophy. His left hip starts out 2' back from where it ends up, over the baseline. His thumb faces the back fence, along with his chest. The elbow hitting structure cocks all the way forward, also facing the back fence. Just try that sometime! His front foot starts at a 45 but rotates parallel to the baseline, allowing the chest to face the back fence. He first supinates his stick hand, and then pronates from the elbow, snapping the forearm at the last milisecond. He holds off the forearm snap until the stick goes under the elbow. He leg drives up just as the stick reaches the trophy pos. And then there is the far left toss pos., which is about 1' farther left when serving dtm or ad side bh. His toss was readable. The stick ends up facing the side fence after pronation.
That may be the best analysis of his serve I've ever seen on paper and video! Awesome stuff this issue.