Modern Tennis Tips by Oscar Wegner

[bhupaes]

Originally Posted by Cheetah

ok. I got confused over the years of debate on this. So oscar says there's acceleration after contact and jy says there isn't? is that correct?

Being awake really early due to jet lag, I thought I might take a shot at this...

My take is both Oscar and JY are right, and there is some misunderstanding on the interpretation of what Oscar is saying.

I believe JY is correct in saying that racquet head speed in the follow through after impact remains below its peak value which is reached just before impact. He has measured it, and that's proof enough for me.

At time same time, I believe what Oscar meant to say is that the racquet does accelerate after impact, in the sense that maximum racquet head speed in the follow through is greater than its speed immediately after impact. That is, speed will increase up to a point before the swing ends. I accept Oscar's thesis that there must be no conscious effort to slow down the racquet after impact - the intention must carry through impact.

One interesting experiment would be to measure racquet head speed in a shadow swing, where the player swings at a holographic image of a tennis ball, and seeing where racquet head speed peaks.

[5263]

Originally Posted by Cheetah

ok. I got confused over the years of debate on this. So oscar says there's acceleration after contact and jy says there isn't? is that correct?

Now I'm confused
How did you get from before/near contact to where you are now on this?

Pretty important here don't you think?

[sureshs]

Originally Posted by Povl Carstensen

I just stood up, held a racket in my stretched right arm, rotated around myself, and pulled the arm in. The acceleration was noticeable.

If you are already rotating around yourself, and allow for more rotations, it might make a difference. A diver starts a rotating jump, then curls in, and reaps the benefits of extra rotations.

If you are only partially rotating, and sometimes not the whole body, and you are looking for an increase in speed in the millisecond before impact that you are pulling in your arm (which you are not actually, since you are hitting out on the ball), I don't think the increase in speed in the millisecond into impact is going to make a difference.

[sureshs]

Originally Posted by bhupaes

At time same time, I believe what Oscar meant to say is that the racquet does accelerate after impact, in the sense that maximum racquet head speed in the follow through is greater than its speed immediately after impact. That is, speed will increase up to a point before the swing ends.

Yes, it is quite possible that the acceleration is still positive (but decreasing) after impact, just like it was positive (but decreasing) before impact, as per toly's studies.

I doubt though that any conscious extra force is exerted by the player just before and after impact in an abrupt fashion. The impact is pretty significant - you can see Federer's frame wobbling. The acceleration will be down, but the speed may still increase, but probably as a consequence of the actions prior to impact.

But the main contention is not this. It is the claim that the racket is moved slowly till it is very close to the ball, almost in the catching position, and then accelerated. That is just wrong. It prompted one person to ask - should I start my acceleration 1 or 2 inches from the ball? So the image is just not teaching the way the pros play.

[JohnYandell]

Bhu,


Actually the deceleration is continuous--it never speeds up after contact and is going 5mph or so by the time it reaches the wrap.

[sureshs]

Originally Posted by JohnYandell

Bhu,


Actually the deceleration is continuous--it never speeds up after contact and is going 5mph or so by the time it reaches the wrap.

OK that is a good clarification. So it is not just the acceleration is decreasing, but it is actually negative? Makes sense - why would a pro expend much energy after impact?

This is what I had read before - that the racket starts to decelerate after impact. But I was not sure how accurate those comments were.

[5263]

Originally Posted by JohnYandell

Bhu,


Actually the deceleration is continuous--it never speeds up after contact and is going 5mph or so by the time it reaches the wrap.

I think this is true as well, but does not address the intent to accel near
impact and thru part of the follow thru to lessen the loss at impact.
As anyone in contact sports like MA and football know, if you don't seek to accel
thru the contact, then your'e hit is weak. Even in those sports you are likely
actually slowing during the process. Coaching is mostly about intent.

[sureshs]

^^^ That seems to be correct too - the old question about why follow thru is important since the ball is gone, and the old answer to that. But the speed build-up happens from much before than just before contact.

[treblings]

i´m waiting for the next modern tennis tip
not that the recent discussion about yanking and accelerating and deccelerating before, during or after contact isn´t totally fascinating

[5263]

Originally Posted by sureshs

^^^ That seems to be correct too - the old question about why follow thru is important since the ball is gone, and the old answer to that. But the speed build-up happens from much before than just before contact.

and you are correct too, but that part is nearly effortless part of the flow,
and the effort comes approaching contact.
Starting the effort too early spoils the hit in any dynamic sport, but may work
in chopping wood contest or something.

[sureshs]

Originally Posted by 5263

and you are correct too, but that part is nearly effortless part of the flow,
and the effort comes approaching contact.
Starting the effort too early spoils the hit in any dynamic sport, but may work
in chopping wood contest or something.

Too early is not getting as close to the ball as almost catching it, as it is claimed, and then accelerating. Such a jerky movement does not happen with the pros, should not happen, and will only result in injuries - it is bad advice. Just beating around the bush will not change the fact that it is wrong.

[5263]

Originally Posted by sureshs

as it is claimed, and then accelerating. Such a jerky movement does not happen

Did I say jerk?

[bhupaes]

Originally Posted by JohnYandell

Bhu,


Actually the deceleration is continuous--it never speeds up after contact and is going 5mph or so by the time it reaches the wrap.

Thanks for the clarification, JY.

[sureshs]

Originally Posted by 5263

Did I say jerk?

No, and the thread is not about you, either

[5263]

Originally Posted by sureshs

No, and the thread is not about you, either

Ohhh, but you did quote me and my post didn't you, lol

[sureshs]

Originally Posted by 5263

Ohhh, but you did quote me and my post didn't you, lol

Yes, and you will see that I did not claim that anybody said it was jerky. I said if someone slowly brings the racket to the ball almost to within catching distance, and then accelerates, it will be a jerky motion. Such advice has already prompted one poster to ask if he should start to accelerate from 1 to 2 inches distance from the ball. So it is dangerous giving advice such as last moment yanking or pulling back or jerky movements.

[5263]

Originally Posted by sureshs

Yes, and you will see that I did not claim that anybody said it was jerky. I said if someone slowly brings the racket to the ball almost to within catching distance, and then accelerates, it will be a jerky motion. Such advice has already prompted one poster to ask if he should start to accelerate from 1 to 2 inches distance from the ball. So it is dangerous giving advice such as last moment yanking or pulling back or jerky movements.

So you are the one using the jerk term...Ok
Just don't surprised when your perception is not accepted.

[JohnYandell]

At the suggestion fo 5263 to post in this thread:

What is the yank?

[Wegner]

The acceleration is through the impact, pulling, while the combined force is across. That causes racquet head speed to go beyond 50 MPH in front of the player while going across. Of course the player would not forcefully accelerate well past the impact, or he would injure or kill himself with the racquet. But his intention is to get the racquet all the way to the finish.

And the racquet speed at the end of the stroke is ZERO and usually pointing backwards, while in front of the left shoulder (for right handers) the racquet head was close to full speed. Why? Because the player at that moment is loose, he has relaxed his arm.

Here is a tip that explains some of the actions:

Yank Across

A tennis groundstroke has been thought, for a long time, to be a linear strike.

Today’s modern players yank the ball across it’s line of flight. Think of it as if going towards the ball with your hand and suddenly changing direction and accelerating through the impact to make the ball both spin and advance at great speeds towards your opponents court.

Nothing like baseball, or cricket, or golf. Tennis is a unique sport, using forces a bit like Martial Arts.

It seems counter-intuitive, but it works like a charm. Let the theoretical experts think what they want. Try it and let us know your results.

The pulling across accelerates the windshield-wiper, which provides the topspin needed to make the ball drop sharply, the yanking gives the ball great speed without abandoning control.

The failure to recognize this and other aspects of modern tennis are the only reasons for the decline in the number of top players from the USA, Great Britain and Australia, previously the most successful countries in the game.

I invite you to view a new two-hour DVD, “The Best of Oscar”, I just released. It will show you what changed tennis in many countries around the world and that this sport is a much easier game than previously thought.

It is easy as well, with these techniques, to copy the best performers and improve your game substantially. All that stands in the way are misconceptions such as thinking that tennis is a linear game.

[Wegner]

Originally Posted by bhupaes

Being awake really early due to jet lag, I thought I might take a shot at this...

My take is both Oscar and JY are right, and there is some misunderstanding on the interpretation of what Oscar is saying.

I believe JY is correct in saying that racquet head speed in the follow through after impact remains below its peak value which is reached just before impact. He has measured it, and that's proof enough for me.

At time same time, I believe what Oscar meant to say is that the racquet does accelerate after impact, in the sense that maximum racquet head speed in the follow through is greater than its speed immediately after impact. That is, speed will increase up to a point before the swing ends. I accept Oscar's thesis that there must be no conscious effort to slow down the racquet after impact - the intention must carry through impact.

One interesting experiment would be to measure racquet head speed in a shadow swing, where the player swings at a holographic image of a tennis ball, and seeing where racquet head speed peaks.

Vic Braden has measured Federer's stroke, in one instance, going from 7 MPH in the racquet head drop, 17 MPH just prior to impact, and over 50 MPH in front of his chest. Very different figures.