Discussion in 'Tennis Tips/Instruction' started by Wegner, Dec 24, 2012.
I don't think there is any pull back immediately before contact.
sureshs, it's not my theory. i haven't tried it out.
I would call it pulling across instead of extending (btw the two can be mixed). But there is some power on tap in this motion, that can be transferred to the ball, plus pulling your arm towards the body increases rotation speed (like in figure skaters fx). Extending the arm lowers rotation speed.
I had thought about that and concluded it cannot be possible. Pulling across yes, but not pulling back, and that too close to contact. The diver or figure skater increase in rotational speed comes by a much larger shortening of an extended arm/body to a much shortened form, and results in significantly more body rotation speed. Both feet need to be off the ground for this to have any meaning (in diving; in skating the ice provides less friction), otherwise friction will override everything. That is hardly the case even in most pro forehands. And even then, a last instant shortening by a small amount, with the body and hand still not close together. should have only a negligible increase in rotation speed into the ball. It would be much better to continue to build up the impact speed instead of doing this, and that is what I see in the videos.
I agree. I have been looking at a lot of youtube videos of pros and I don't see a change in direction to yank or pull back. Yes, pros pull up and across. Yes, at some point the end of the rotation is reached and arm, hand, and racket begin to wrap back toward the body. But, I don't see an abrupt pull back in the pro game. It looks like it flows smoothly up, thru and across and than wraps in WW completion. I even studied pro forehands from the side view and you can stop the stroke at contact and the hand moves up, across and THRU or BEYOND the contact point. So, yes it is a deflecting blow but there is an element of THRU and extension BEYOND the contact point as well. The ball is gone - off the strings - before the hand starts back toward the body.
My theory is you vary the degress of up, across and thru for more spin or more drive.
Heard enough puffing, unsubstantiated statements, and arguments in this thread so unsubscribing. So far I still side with Yondell.
Read again. I didn't mention 'yanking'. And it's not just rotation. Like I said, some people can't or won't see it.
I don't see any 'pull back' either from any pros.
I think my original thinking on this was correct. My speculation is that if you plot the (eventual) contact point on the racket face as an arc, then it should meet the arc (or line) you want the ball to follow (after impact) such that the two curves are continuous at the impact point. At this point, the racket face can be in a perpendicular plane to the common tangent, or more closed.
How are people measuring or defining pull back, yank or swing across?
Draw a straight line from one shoulder to the other and call that the shoulder axis. Then from above looking down - the angle between shoulder axis and the humerus seems to reduce from start of stroke to finish. Also, the angle between the humerus and the forearm reduces from start to finish (Ferrer?).
These angles are reduced most noticeably after impact because at that point the the shoulder rotation slows to a stop but the arm is still pulling due to kinetic chain timing.
That is what I picture when I think of pulling across.
Extension through the ball will happen via shoulder rotation. On a full turn, the shoulder will start roughly behind my head and as I finish the stroke my shoulder will end up in front of my chin. For me that is more than 2 feet of forward shoulder displacement some of which will translate to racquet extension through the ball.
So long as my shoulder is rotating as it should, extension through the ball will happen even if I'm pulling across.
My simplistic way of looking at this whole debate.
^^^ Comes back to the same point. You seem to define racket extension through the ball as the motion of the racket in the eventual path of the ball, during the swing. Others define it in terms of how much the racket moves in the eventual path of the ball after impact. Yet others use it to describe forward extension only, not extension towards the target in CC shots.
Not at all imo. Btw I dont know what pull back is, and I think yank is a bad word. But pulling across the body and ball (but still through also), I understand.
Look at the video. To me theres a lot of across ball and body action. Admittedly not on a couple of low balls. And to a lesser degree in a passage where he hits loopier, higher, more topspin balls. But otherwise, right from the beginning, I think I see it. It makes sense also, if you want to get action on flatter balls, you do not want it to be all topspin, or they would be short.
The need for less friction was to increase rotational speed. It has nothing to do with the tennis shot. I was commenting only on whether the rotation speed will increase with the hands coming in, and I said it will be negligible and friction will make it even less of a factor.
No one is disputing that pros finish across the body.
Thanks again for the great help through the years Oscar. Your ideas and communication skills have helped me help many students.
I could not give a dang about what exactly happens with each stroke, what pulls and how far, the angle at contact....yawn.
All I know is that I have used your techniques to help kids win in juniors and some get scholarships to pay for their education.
Thanks for that and please keep the tips coming.
Doesn't your business revolve around selling false hope
I gotta say John your whole tennis instructional website revolves around hyped marketing....So shame on you for trashing someone who just figured out a better way of selling their products or systems. Face the facts anyone can take a bunch of slow motion videos and make a good analysis of whats going on...But bottom line is you have to have athletic ability to play tennis the correct way...95% of tennis is hit and giggle....That part drives me crazy, you have put the time in on the court and off the court to really become a real tennis player....
John was wronged by Oscar so he fights against Oscars methods while he himself is hyping his own services under a different banner. I still do not know what the bad blood is about.
I am pretty confident if someone gives me slo mo video I can make a very good analysis. At least enough to make some newb hacks think I know what I am talking about.
John has put a highspeed video of Dimitrov in the other thread. i am interested how you would analyze it
hint - there is no 'bad publicity'.... all these free eyeballs....
I'm confused by this last part. Do you think any tennis teaching professional thinks that a player can improve without practice? Or any teaching pro tells his students not to practice?
As usual you guys have it wrong. According to you I have hurt my marketing efforts by posting here. And if you think all publicity is good publicity look at Ted Bundy or the current speaker of the house...
"Anyone" could put together that high speed collection? That's an interesting claim! It took me about 15 years but I am sure it was easier than I thought...lol. As for analysis, you just have to look at the threads here to see that video may be the basis for truth but that doesn't mean it isn't susceptible to poor analysis.
As for the alleged false hope, well we have a section on the site with about 100 before and after examples of players using our information and changes there are real and documented. You can lead a horse to water, etc, inner boy.
And as for practice, if you look at my book you see I believe that not just practice, but disciplined, progressive practice based on good information is fundamental. That's pretty obvious and not sure why anyone would say practice was irrelevant. Oh except Oscar who claimed watching his DVDs once would solve all technical problems...
And speaking of the thing with Oscar it's about the truth and representing what actually happens and doesn't happen in tennis, accurately representing what coaches actually believe and how they may have come to believe it, and how certain ideas influence players for better or worse. What can I say, I don't like false claims.
Will have a look
The comments on that so far indicate that the hands separate before the bounce and there is good extension before the racket comes across. High frame-rate video shows what is really happening, which can often be missed by the naked eye or preconceived notions.
PS: and no "yanking" or "pull back" is seen
That kind of post is what gets threads deleted. Makes no sense and is just an attack.
Oscar, Would love to get an analysis for John's recent video link in his thread from Oscar Wegner
I don't get the recent posts attacking technique discussions.
I realize some people are angry, but at least of lot of them seem to have legitimate differences of opinion. Recently we've been getting angry posts by people arguing that discussing technique is bad and that people should just shut-up and go practice. The whole point of discussing technique is to make the practice more helpful.
And yet these people seem to want to read this forum. Why don't they go and practice instead?
I don't know about others but I'm old and lazy...,
I agree - no pull back that I see. My opinion is you can think stop the off side or even pull back on the off side to generate power on the hitting side. For example for a right handed player, the left shoulder may pull back to speed up the right shoulder and hitting arm. But, I have watched many pro forehand including GD clip and I don't see a pull back at/before contact in the hitting hand, arm or shoulder. Hitting arm seems to flow thru contact - up, thru and across until it wraps and finishes by L shoulder.
I start to think that all this stuff is hog wash... with some practice, the body should know what motion generates the most power.
if there is a nail at the contact point, and you tell the student to hammer this nail hard into a 2x4 with a FH grip, he will know what motion drives the nail the deepest.
point the nail slightly up towards the sky, then you get topspin.
My guess is that you've never coached or taught tennis. Correct me if I'm wrong.
I've found that coaching some students makes a huge difference even in a short period of time. I also know players who have been playing tennis for more than a decade and have terrible form and terrible shots and have never taken a single lesson.
yes it's all hog wash--except the part about driving nails. That is up there with the ultimate worst tennis tips of all times for so so many reasons, but it would be hog wash to go into why.
have worked with high school/rec players... also have coached golf....
I am not saying 'don't take lesson', I am saying these body-parts analysis is hog wash... if we relate a tennis stroke to another task (e.g. hammering a nail), perhaps student can figure out what motion generates the most power.
This part is not hog wash, and that much is clear.
OK, then I believe you should be more careful about how you express yourself, as I interpreted your original complaint as being a criticism of getting coaching or lessons.
Teaching by analogy might work, but I don't understand your hammering nails comparison. To me, hitting a tennis ball is not at all like hammering a nail.
I don't know how to take a lot of Wegner's advice. It seems to me he is exaggerating things in his descriptive language. For example, the pros don't slowly approach the ball with a fh and then accelerate at the last second. What they tend to do, from my personal observation and slow motion video, is accelerate hard from the end of the backswing into contact. Does his advice give the same result or are students ignoring his advice and accelerating earlier anyway?
Teaching ideas don't always correspond to reality--that's well accepted. What people find ridiculous is claims about reality that are obviously false and don't correspond to even the most rudimentary physics. And the complete unwillingness to address the errors... it's so revolutionary it doesn't have to bear any relation to reality apparently.
I am watching the Chennai Open now, and Anand Amritraj is commentating. Two of his comments struck me. He said, in his playing days, the ball would be around the knees, but today it is much higher. and require much more upper body strength. The strength thing was a new insight for me.
The second thing he said was that Cilic's forehand has a technical glitch and he was surprised that his coach Bob Brett has not worked on it.
Here is a challenge to you coaches: what is the glitch, if any? The double pumping too-early takeback?
To me, it is not an exaggeration. I mean, the sentences I have put in bold are just the opposite of each other. The first is not a symbolic overstatement of the second.
It depends on what the motivation is. Federer is probably not interested in the physics of tennis, but the book by Rod Cross and the other guy is a well-respected classic. Many people think that racket design is a farce, but Wilson has a well-equipped design lab for it. Everything has a place. You are assuming that if someone does not discuss body parts, somehow that will make him a better player than he is. It doesn't work that way.
Where the hell is the fh close up super slow mo in this terrible clip??
interesting challenge, here´s one for you, find a decent video in hd of Cilic forehand for us to analyze
I dont think the centrifugal force from pulling your arm in is neglible, but never mind.
Of course pros finish across the body. But would you agree that in the video there is quite a lot of across the ball hitting (from about 4-5 o'clock to about 10-11 o'clock)? And vice versa on the backhand btw.
friction is not a factor... upper body still rotate with feet planted on the ground.... suresh you don't get ice cream for the friction thing.
I hit bent fh... arm has to contract otherwise it straightens during core rotation and the shot is ruined... power still comes from the hip though.
you can it yank, i call it 'maintaining the arm bend'.
There is centrifugal force whether or not you pull in your arm. If you mean the increase in angular velocity due to bending you arm and bringing it closer, I think the increase will be negligible. You should also realize that if the arm is truly brought inwards, the ball cannot be hit outwards, so the situation is physically impossible.
This explains a bunch about what you don't about tennis strokes.
Why don't you explain it then, considering that video evidence has contradicted everything claimed about yanking and last minute abrupt acceleration?
hehehe that was the challenge - to find a good clip
Apart from a very pronounced "racket up" phase, what is different about his forehand in the clip above?
Is Anand calling that a glitch?
He got banned again
Does no good to explain it to you, and is likely obvious to most others what you
missed with your comments.
I don't think you will find any quotes from me suggesting to yank or be abrupt.
Separate names with a comma.