Interactive Forum Februrary 2013: Petra Kvitova Forehand

[vgrin545]

The flip.

Hi John,

I noticed that some people do not understand what the flip is.

I am attaching the .mov file where my 13 year old sudent is trying to show the flip. I am filming her from behind while her grandmother is tossing the balls to her. While the stroke is only 10% of the finished product, it is clear that girls can do the flip.

[johnyandell]

V,
couldn't get it to open! love to see it though. The flip will become part of the general lexicon as time passes!!

[stotty]

Hi John,

I noticed that some people do not understand what the flip is.

I am attaching the .mov file where my 13 year old sudent is trying to show the flip. I am filming her from behind while her grandmother is tossing the balls to her. While the stroke is only 10% of the finished product, it is clear that girls can do the flip.

Vgrin,

Upload it to Youtube...that's what I do...be great to see it. It's great when coaches upload their work to the forum for others to see.

[julian1]

Fink on Kvitova

So, is Tennisspeed (http://blog.tennisspeed.com/) BG's blog? Sure seems like it must be. In any case, it is even tougher to digest than Brian's articles here on Tennisplayer with JY's editing skills. I just haven't found the time to slog through the whole thing although I would like to.

And this is turning out to be an interesting little thread. BTW, I wrote in 10sBalls.com after she won the WTA Finals in Istanbul that I thought Kvitova was going to rule the roost for a few years. It seems people are trying to point out that she hits the ball pretty big inspite of a rather minor "flip". But to me, when she is on, the only player that has any chance of staying with her is Serena. It seems to me she hits bigger than any of the other women and the big lefty serve is a huge weapon. Her struggles are a puzzle to me, but I don't think it is the mechanics of her strokes; more likely fitness and mental focus and commitment. She seems to me almost afraid of the trappings of being on top of the mountain.

don

http://www.tennischannel.com/news/NewsDetails.aspx?newsid=12115

Not very deep,but I have thought you would be interested

[10splayer]

I disagree that it is ALL or nothing.
I have to spend some time to think how to figure out how to convince you
I am NOT a quick thinker

Have you thought about this yet?

[julian1]

I Failed Miserably

Have you thought about this yet?

I FAILED MISERABLY.
However
I can provide couple of loose thoughts.
1.I have looked into following cases:
Djokovic
Stosur

http://www.tennisplayer.net/members/tour_strokes/tom_downs/sam_stosur_forehand/index.html

Kvitova
Gulbis
Sharapova
2.I have tried to answer a very simple question:
do all of them have THREE ssc's?
a) ssc of muscle of a rotator cuff
b) ssc of an UPPER arm
c) ssc of a FOREARM
3.What are pauses between ssc's?
How do you know/see that an ssc has been done/performed?
4.Can we try to control ALL THREE ssc's independently (say by brain)

The bottom line is that I am very confused about ALL 4 ASPECTS.
I have to go to hit some fluffy balls at my club.
I should be back

[10splayer]

I FAILED MISERABLY.
However
I can provide couple of loose thoughts.
1.I have looked into following cases:
Djokovic
Stosur

http://www.tennisplayer.net/members/tour_strokes/tom_downs/sam_stosur_forehand/index.html

Kvitova
Gulbis
Sharapova
2.I have tried to answer a very simple question:
do all of them have THREE ssc's?
a) ssc of muscle of a rotator cuff
b) ssc of an UPPER arm
c) ssc of a FOREARM
3.What are pauses between ssc's?
How do you know/see that an ssc has been done/performed?
4.Can we try to control ALL THREE ssc's independently (say by brain)

The bottom line is that I am very confused about ALL 4 ASPECTS.
I have to go to hit some fluffy balls at my club.
I should be back

A couple random thoughts for you to ponder. I said it's more or less an all or nothing proposition because I'm not sure how (anatomically speaking) a shoulder can be internally rotated and the forearm externally rotated in the backswing before the pull...In the case of type 3 forehands i see shoulder, upper arm, forearm all internally rotated before the pull.

Another issue is the time frame between eccentric to concentric contractions.
The type three maximizes this effect, because of the quick internal to external rotation..(flip)

[julian1]

Each ssc around 40 miliseconds

A couple random thoughts for you to ponder. I said it's more or less an all or nothing proposition because I'm not sure how (anatomically speaking) a shoulder can be internally rotated and the forearm externally rotated in the backswing before the pull...In the case of type 3 forehands i see shoulder, upper arm, forearm all internally rotated before the pull.

Another issue is the time frame between eccentric to concentric contractions.
The type three maximizes this effect, because of the quick internal to external rotation..(flip)

There are some "speculations" that each ssc takes 40 miliseconds.
Whether ssc's overlap I do NOT know
I do NOT know whether I am answering your question.
NOT sure why do u expect me to know answer to your second question

[10splayer]

There are some "speculations" that each ssc takes 40 miliseconds.
Whether ssc's overlap I do NOT know
I do NOT know whether I am answering your question.
NOT sure why do u expect me to know answer to your second question

Maybe we are talking bye each other here. What I'm saying is that to maximize the stretch shorten cycle, the arm has to be internally rotated when the racquet is pulled. This quick internal to external rotation of the arm is what really "loads" the arm for the forward swing... In the case of Sharapova, her arm is externally rotated the entire backswing...

I might do a short video on the subject, as it's much easier to explain my thoughts in spoken word.

[stotty]

My take

It's tricky stuff this. The SSC is a sequence of events where you have bones going one way and muscles resisting. Much is going on that cannot be seen with the naked eye. The millisecond precision part is happening under the skin, and exactly what happens and precisely when is hard if not impossible to determine.

For coaching purposes it's perhaps enough to know that we have to meet certain positions with students in order to give them the best chance of success. Maximising the SSC is probably down to practice and a player's innate ability. Anything beyond this is probably outside coaches' control. This is probably true of many aspects of coaching and not just the SSC.

This is my take after avidly watching this thread since it started.

[johnyandell]

Stotty,

I agree. It is impossible to make accurate statements about what is going on inside the body at the muscluar level in terms of things like stretch shorten cycles without making quantitative measurements. The rest is inference and opinion which may be accurate--or not.

If the positions that science says produce these effects are met, that is the best we can do as coaches--along with observing the results.

[julian1]

I will send you a personal message tomorrow

It's tricky stuff this. The SSC is a sequence of events where you have bones going one way and muscles resisting. Much is going on that cannot be seen with the naked eye. The millisecond precision part is happening under the skin, and exactly what happens and precisely when is hard if not impossible to determine.

For coaching purposes it's perhaps enough to know that we have to meet certain positions with students in order to give them the best chance of success. Maximising the SSC is probably down to practice and a player's innate ability. Anything beyond this is probably outside coaches' control. This is probably true of many aspects of coaching and not just the SSC.

This is my take after avidly watching this thread since it started.

I will send you a personal message tomorrow
Technically a ball is in your court (a pun attempted)

[julian1]

Jump or NOT to jump? preferably NOT

It's tricky stuff this. The SSC is a sequence of events where you have bones going one way and muscles resisting. Much is going on that cannot be seen with the naked eye. The millisecond precision part is happening under the skin, and exactly what happens and precisely when is hard if not impossible to determine.

For coaching purposes it's perhaps enough to know that we have to meet certain positions with students in order to give them the best chance of success. Maximising the SSC is probably down to practice and a player's innate ability. Anything beyond this is probably outside coaches' control. This is probably true of many aspects of coaching and not just the SSC.

This is my take after avidly watching this thread since it started.

Combined effect of elastic energy and myoelectrical potentiation during stretch-shortening cycle exercise

C. BOSCO,
J. T. VIITASALO,
P. V. KOMI,
P. LUHTANEN

Article first published online: 8 DEC 2008

DOI: 10.1111/j.1748-1716.1982.tb07024.x

© 1982 Scandinavian Physiological Society

Issue
Acta Physiologica Scandinavica
Acta Physiologica Scandinavica

Volume 114, Issue 4, pages 557–565, April 1982

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In addition to the utilization of muscle's elastic energy enhancement of performance in exercise involving stretch-shortening cycle might be also due to simultaneous increase of myoelectrical activity.


This hypothesis was tested by examining three athletes during jumping exercise on force-platform. Vertical jumps were performed with and without preliminary counter-movement, and the jumps were called counter-movement jump (CMJ) and squatting jump (SJ), respectively.


In both conditions several jumps were performed also with extra loads on the shoulders (15–220% of b. wt.). Additional droppingjumps (DJ) were executed from different heights (20–100 cm). During jumping exercise myoelectrical activity of selected muscles from the quadriceps femoris was monitored with surface electrodes. The results obtained were similar to those reported in isolated muscle and as expected, the prestretch in CMJ shifted the force-velocity curve of concentric work to the right. In two cases enhancement of performance was attributed primarily to restitution of elastic energy because myoelectrical activity was similar to that observed in SJ. In one subject increased myoelectrical activity was observed during the concentric phase of CMJ. In DJ condition the EMG activity during eccentric phase was much higher than in SJ.


Therefore the high performance in this condition was attributed to both elastic energy and reflex potentiation. In eccentric work of CMJ the average force decreased with the increase of stretching speed. This phenomenon was associated with a light increase of EMG activity. The observed results emphasize that both elastic energy and reflex potentiation may operate effectively during stretch-shortening cycle activity.

[stotty]

Combined effect of elastic energy and myoelectrical potentiation during stretch-shortening cycle exercise

C. BOSCO,
J. T. VIITASALO,
P. V. KOMI,
P. LUHTANEN

Article first published online: 8 DEC 2008

DOI: 10.1111/j.1748-1716.1982.tb07024.x

© 1982 Scandinavian Physiological Society

Issue
Acta Physiologica Scandinavica
Acta Physiologica Scandinavica

Volume 114, Issue 4, pages 557–565, April 1982

Additional Information(Show All)

How to CiteAuthor InformationPublication History
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Search Scope
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Keywords:

Muscle mechanics;
stretch-shortening cycle;
muscle elasticity;
muscle activation;
myoelectrical potentiation

In addition to the utilization of muscle's elastic energy enhancement of performance in exercise involving stretch-shortening cycle might be also due to simultaneous increase of myoelectrical activity. This hypothesis was tested by examining three athletes during jumping exercise on force-platform. Vertical jumps were performed with and without preliminary counter-movement, and the jumps were called counter-movement jump (CMJ) and squatting jump (SJ), respectively. In both conditions several jumps were performed also with extra loads on the shoulders (15–220% of b. wt.). Additional droppingjumps (DJ) were executed from different heights (20–100 cm). During jumping exercise myoelectrical activity of selected muscles from the quadriceps femoris was monitored with surface electrodes. The results obtained were similar to those reported in isolated muscle and as expected, the prestretch in CMJ shifted the force-velocity curve of concentric work to the right. In two cases enhancement of performance was attributed primarily to restitution of elastic energy because myoelectrical activity was similar to that observed in SJ. In one subject increased myoelectrical activity was observed during the concentric phase of CMJ. In DJ condition the EMG activity during eccentric phase was much higher than in SJ. Therefore the high performance in this condition was attributed to both elastic energy and reflex potentiation. In eccentric work of CMJ the average force decreased with the increase of stretching speed. This phenomenon was associated with a light increase of EMG activity. The observed results emphasize that both elastic energy and reflex potentiation may operate effectively during stretch-shortening cycle activity.

Hi Julian,

I rested my case in my last post. As coaches, it's enough to know the positions you have to meet to achieve a type 3 forehand. BG's two articles are perfect in this respect. He tells us all we need to know without delving into stuff we will never understand and have little need to know - unless, of course, you love the study of in depth biomechanics.

The article you posted is great and interesting, but I would be way out of my depth to comment on it. My concern as a coach is making positions...it's the crux of the job. I am willing to learn biomehanics to the degree that I will actively need it. Beyond this, I'm leaving it to the likes of BG.

[julian1]

Let me pose a coaching question

Hi Julian,

I rested my case in my last post. As coaches, it's enough to know the positions you have to meet to achieve a type 3 forehand. BG's two articles are perfect in this respect. He tells us all we need to know without delving into stuff we will never understand and have little need to know - unless, of course, you love the study of in depth biomechanics.

The article you posted is great and interesting, but I would be way out of my depth to comment on it. My concern as a coach is making positions...it's the crux of the job. I am willing to learn biomehanics to the degree that I will actively need it. Beyond this, I'm leaving it to the likes of BG.

Hi,
let me pose a coaching question.
What kind of drills can one suggest to IMPROVE ,for example,a flip for DOUBLE HANDED BACKHAND- a bit related to some "pat the dog discussions".
I was a bit surprised that a conversation about "pat the dog" was discontinued
unless I missed something (I was away from a forum for a month
and I will be away for three months again).

By the way I appreciate your previous posts.
I will respond to your post about "checkpoints" as well
Regards,
Julian