Grigor demonstrating wrist snap on FH

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Stupendous1HBH

Guest
I came across this video earlier today as I was re-studying his serve (as I try to model mine after his) and around the 6:20 mark onward, he hits some really nice snap forehands. Maybe a good video for someone out there looking for more racquet lag and wrist snap with a loose arm on the forehand side. Enjoy.

 

LeeD

Bionic Poster
When you lag back, you don't snap your wrist, the lag does the work for you, so you can hit relaxed wrist. By "snapping" your wrist, you're implying an active use of the forearm muscle, which would tend to lock the wrist, not snap it forward.
Novak DJ also says to "snap the wrist" for serving pace.
Great player's play really great, but don't always know what they're actually doing.
 
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Stupendous1HBH

Guest
Call it whatever you want, but he's snapping his wrist immediately after the racquet lag ;)
 
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Stupendous1HBH

Guest
Let's remove the "snap" word and call it "super fast wrist-forearm pronation" which looks like a snap...
 
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PittsburghDad

Guest
The pros aren't using wrist snap. However.....you might be able to make a case that snapping your wrist into the ball might be effective at the rec level. There's not the issue of exquistite timing wrapped into a vicious RHS swing that would be destroyed by actively snapping the wrist into contact.
 
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Stupendous1HBH

Guest
I watched a video just now of Roger hitting in super slow mo of a few forehands. It is just racquet lag so I stand corrected.

In Grigor video in regular motion, it appears to look like wrist snap but it's so quick of an action that it's hard to really see what is happening with the wrist but it's just falling back a bit and stays locked and it's just super fast racquet lag and acceleration at it's best.
 

5263

G.O.A.T.
when you see that type action in the wrist, it is reaching for the outside of the ball to hit a draw fh
 
When you lag back, you don't snap your wrist, the lag does the work for you, so you can hit relaxed wrist. By "snapping" your wrist, you're implying an active use of the forearm muscle, which would tend to lock the wrist, not snap it forward.
Novak DJ also says to "snap the wrist" for serving pace.
Great player's play really great, but don't always know what they're actually doing.

Yes. Arm internal rotation and wrist snap can feel pretty similar since both snap the racket ahead of the hand and pros are no biomechanics experts.

Since the hand has the best fine motor skills and best proprioreception most great players tend to feel the stroke more in their hand than in their arm.

A pro is not thinking now I rotate my arm but he is using external feelings like throw the racket forward (there are actually studies that external feelings work better than internal feelings like joint and muscle movements) and he is going to do that with his hand even though there might be underlying movements more upstream.
 

Chas Tennis

G.O.A.T.
The OP video is 30 fps and has large motion blur.

Slow motion video with small motion blur.

Rob Cherry Essential Tennis close up clearly showing the wrist joint motions on the forehand.
http://robcherrytennis.com/grigor-d...motion-forehand-1-western-southern-open-2014/

1) I can't see much wrist motion before impact for the forehands of the Essential Tennis video.

2) How much internal shoulder rotation (ISR) occurs before impact? Does it contribute to forward racket head speed?

To do single frame on Youtube use the "." & "," keys.

At what times of these videos is the wrist motion that the OP means? Times? When the time scale goes from, for example, 4 sec to 5 sec, you can count the number of times that you press the "." key to give a finer time than just the "second" time scale. Posting pictures start & stop frames for the wrist action or 'snap' would be helpful. (I can tell you how to post them using the MS Snipping Tool of Windows 10.)

Which defined wrist joint motion(s) are meant?
https://www.google.com/search?site=......1.1.64.img..0.19.1496...0i24k1.azXG9_FE7zo
 
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Chas Tennis

G.O.A.T.
when you see that type action in the wrist, it is reaching for the outside of the ball to hit a draw fh

What is a "draw" forehand?

What is "that type action in the wrist" before impact that you are referring to as it appears in the Essential Tennis video of post #12? At what time of the video?

The frame at the time of the video changes, say from 4 to 5 seconds, you can then start counting the number of frames advanced to an event to get, for example, 5 seconds and 12 frame advances to the start of wrist flexion. That way you can identify the exact frame you want.
 
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TennisCJC

Legend
Grigor is not snapping his wrist.

And, most rec players are far better off training to eliminate wrist movement just before, during and just after contact. When the ball is traveling at you at 50 mph or more and you are trying to hit a topspin groundstroke back; any attempt to consciously snap the wrist will result in an inconsistent FH and likely a wrist injury if you continue to do it over time.

Either lay the wrist back very early at prep - Nadal lays the wrist back very early, or prep with a neutral wrist and let it lay back after the take back as you start forward. Federer and Grigor only lay the wrist back a little and prep and they let it lay back more as they start the forward swing.

But, when you start the forward swing, don't muck with your wrist. Just concentrate on a smooth swing through the ball. If anything, try to keep the wrist from snapping.
 

Chas Tennis

G.O.A.T.
yep the arm is like a whip. The force comes from legs, torso and shoulder. Yes the wrist snaps like the crack of a whip but its a passive motion.

"Passive motion" defined as you used it?

In the Hill Muscle Model there are active muscle forces and passive muscle forces:

1) Active muscle forces occur when the brain or other source sends EMG nerve signals to muscle cells. These signals cause Ca ions to be released into the muscle cell's sarcomeres. Then the sarcomere's Actin and Myosin form cross bridges that ratchet and cause the sarcomeres to shorten. Search terms for videos and animations of how active forces are produced by Actin & Myosin.

2) Passive muscle forces occur when a giant elastic molecule in each sarcomere, Titin, is stretched like a rubber band and also can supply shortening forces to the sarcomere. I don't know how Titin forces are triggered or controlled, nerve signals, etc. Search: Titin (a hot research topic)

There are other ways that joint motions can occur without any forces from the muscles that are attached at that joint.

3) External Forces. Other joint movements can occur from external causes and forces. For example, if I move my arm quickly across in front of my chest and suddenly stop it, my wrist joint may flex forward rapidly from the inertia of the hand. Try it with a relaxed wrist but not fast enough to be stressful. In normal conversation, that wrist flexion might be spoken of as 'automatic' or 'passive'. The term 'passive' has a different meaning in this conversational usage.

There can be misunderstandings in a discussion of body motions especially when the word 'passive' could be used in a defined way as in the Hill Muscle Model or in a conversational way without defined meaning. This can be especially ambiguous and misleading if readers look up the term 'passive', do a Google search, or read a technical publication. 'Passive' often seems to fit both ways.....
 
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Chas Tennis

G.O.A.T.
On the Dimitrov forehand does the any wrist joint motion impart forward motion to the racket?

Correction - I just looked at the Dimitrov wrist motion again and he does flexion - maximum wrist extension to small extension at impact - and that produces considerable racket head speed.

See post #19.
 
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philosoup

Rookie
On the Dimitrov forehand does the any wrist joint motion impart forward motion to the racket?

Yes. By stretching and compressing lots of tendon, ligaments and cartilages in the wrist and other tennis tissues. No firing of those snap muscles though, no matter what they are.
 

Chas Tennis

G.O.A.T.
Yes. By stretching and compressing lots of tendon, ligaments and cartilages in the wrist and other tennis tissues. No firing of those snap muscles though, no matter what they are.

Recent research indicated that for the long muscles the tendons did not play as important as part in stretching as had earlier been thought. The Titin in each sarcomere probably contributes most force despite what text books had been saying for decades about tendons. This is one reason why Titin research is important. Unfortunately, the new text books may not have caught up yet but don't believe it when they say the tendons are the source of muscle stretched force - it's the Titin!

I am trying to take the approach of the researchers, Marshall, Elliott et al, that examined the joint motions that contributed to the serve, forehand and maybe also other strokes. They measured the most significat joint motions and the distance from their axis of rotation to impact. Each joint motion was then assigned a 'contribution' to racket head speed at any instant including impact. Search: Biomechanics and Tennis, Elliott They also measured the forehand, but that forehand technique of 20 years ago, compared to Dimitrov's today, may have changed. ?

I looked up the table in Biomechanics and Tennis. Forehand in red. 20% of forward racket head speed at impact from wrist flexion and radial deviation. Correction - on looking at the video again 20% seems reasonable for Dimitrov wrist flexion.

Table 2 Approximate contributions to impact racquet velocity (%)

Power serve
Topspin forehand (forward direction)
Shoulder 10 15
Upper arm
 Horizontal flexion 15 25
 Internal rotation 40 40
Forearm
 Extension Negligible Negligible
 Pronation 5 Negligible
Hand
 Flexion (palm/ulnar) 30 –
 Flexion (palmar/radial) – 20

Correction - Looking at the video again there is enough flexion to be considerable. Maximum wrist extension to less extension, that's wrist flexion*, at impact on second viewing seems considerable for racket head speed in comparison to the contributions of the body turn and shoulder joint swing. Look at Dimitrov's maximum wrist extension and then his extension at impact - that is, wrist flexion*. The distance from the turning body and shoulder to impact is considerably longer than the wrist to racket impact spot meaning higher racket head speed from the body turn and shoulder.

Look at the Essential Tennis video and look at each joint and estimate the racket head speed being produced by each joint motion. Think of each joint motion by itself.

* [There is a confusing issue in describing joint motions - both location and motion use the same terms -
1) Anatomical Terms of Joint Location - describe joint angle with reference to a defined zero. Example, 'The wrist is at an angle of extension of 15 d.'
2) Anatomical Terms of Joint Motion - describes the direction of joint travel toward the maximum joint angle of for example, flexion or extension.
Example, 'The wrist is flexing' - meaning moving toward the angle of maximum flexion.]
 
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philosoup

Rookie
The distance from the turning body and shoulder to impact is considerably longer that the wrist to racket impact spot meaning higher racket head speed from the body turn and shoulder.

Distance is just one thing. If it was a spring, a spring made of steel is much powerful than plastic at same distance. Wrist joint extension is a hard spring.

The other thing is that the non-snap snap bites the ball deeper in the string bed, creates more fiction, amplifying the power from the shoulder and body.
 

Chas Tennis

G.O.A.T.
........... Wrist joint extension is a hard spring.
.................

The wrist is in a position of extension at impact but its motion is flexion, as explained in the footnote of post #19.

Flexion of the wrist can be performed by wrist flexor muscles in the forearm that connect around the wrist with tendons. In the lag these muscles would be stretched and could be used to add speed to the racket head for impact. Maybe the finger flexors would also act to flex the wrist.? I don't know of other tendons in the wrist that would play a part in stretching but the wrist is complicated and there may be.

Cartilages act as cushions between the two bones of a joint. I don't know about their elastic compressible properties but they cannot move very far. I don't think that they can store much energy.

Ligaments connect one bone to another. I don't know about the elastic tensile properties of ligaments but I believe that they would only be pulled hard near the end of the joint's range of motion, a short distance for storing energy. The wrist appears to be near the end of its range of motion for extension at the end of 'lag'.

That same joint position of extension near the end of the range of wrist motion would also stretch the wrist flexors in the forearm. Those muscles with their Titin and tendons are the force chain that I believe is most important. A stretch shorten cycle of the wrist flexor muscles seems the likely source of wrist racket head speed. The muscle length and its sarcomeres are also known to stretch over long distances and build up elastic energy.

Ligaments are short and probably cannot stretch very far but I don't know of measurements. In my opinion, ligaments mostly hold the bones in place at joints.

Think of a long rubber band (wrist flexor muscles) and a very short rubber band (ligaments) and how they would store energy when stretched.

Wrist flexors of the forearm. These are the long muscles that are stretched by the extended wrist that results from the 'lag' of the forehand. Finger flexors too?

Wrist ligaments. Slow and detailed. Says the wrist joint involves the 3 bones where they meet the radialis and ulna. Describes the ligaments. Moves on to the hand.

This is getting to be an interesting thread.
 
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bitcoinoperated

Professional
When you lag back, you don't snap your wrist, the lag does the work for you, so you can hit relaxed wrist. By "snapping" your wrist, you're implying an active use of the forearm muscle, which would tend to lock the wrist, not snap it forward.
Novak DJ also says to "snap the wrist" for serving pace.
Great player's play really great, but don't always know what they're actually doing.

Yup, this is one of the fundamental misunderstandings of the modern tennis stroke. The wrist does what it does as a consequence of a proper swing motion, it moves but it is passive.

I can see this thread becoming another "hold the ball" pseudo-science nightmare.
 

Chas Tennis

G.O.A.T.
..................The wrist does what it does as a consequence of a proper swing motion, it moves but it is passive.
.........................................

In the Essential Tennis Dimitrov video the wrist goes from about 90 d. extended (near maximum) to about 45 d. at impact, in other words, he flexed his wrist about 45 d.

When you use the term 'passive' do you mean that he used stretched muscles in his forearm for the forces to flex his wrist joint? OR,
Did his wrist joint flex because of some other unidentified motions?
 

Chas Tennis

G.O.A.T.
Frank Salazar overhead video from Fuzzy Yellow Balls videos, processed by Toly.

As Salazar accelerates his hand forward the racket inertia pulls it back to maximum wrist extension where it is at a tangent to the near circle of his hand path. At this time of maximum wrist extension, the wrist flexor muscles are likely stretched. Between maximum wrist extension and impact the racket could experience the forces from the wrist flexor muscles plus centrifugal forces from rotation around the upper body center. Both of those forces would tend to cause wrist flexion as seen in the video above and of Dimitrov in post 19. The centrifugal force and wrist flexor forces are unknown. The centrifugal force could be calculated.

Max Wrist Extension. Frame during lag when the wrist has extended to its maximum. The racket is tangent to the hand path. This occurs because the hand accelerated forward and the inertia of the racket causes the wrist to extend.
5919A3483B63440A8D61967AFE6A6898.jpg


Wrist Extension at Impact. Frame just before impact. The wrist extension is less at 46 d. The wrist has flexed between the max extension frame and this frame.
C4CAE14C444E406B9891A4CFDEA8E509.jpg


To demo the centrifugal force: the racket could be held at tangent, 90d wrist extension, as during the lag and the body/arm rotated as seen in the Salazar video above. Don't do this rapidly with stress but just enough to feel the centrifugal force. Centrifugal forces should be best felt after all accelerations are over, not during accelerations. Centrifugal force will tend to move the racket out. This is best seen viewing the overhead Salazar video.

1) forces from stretched wrist flexor muscles (unknown).
2) centrifugal forces will occur due to rotation rate and radius of hand path.
3) hand still accelerating forward? This force is in the opposite direction of #1 & #2 and would tend to reduce the effects #1 & #2.
 
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Fintft

G.O.A.T.
The OP video is 30 fps and has large motion blur.

Slow motion video with small motion blur.

To do single frame on Youtube use the "." & "," keys.

I can't move frame by frame in youtube, but as seen in your slow motion video, Dimitrov doesn't seem to snap his wrist. End of story for me and as someone else put it, amateurs shouldn't snap their wrists.
 

Dolgopolov85

G.O.A.T.
The pros aren't using wrist snap. However.....you might be able to make a case that snapping your wrist into the ball might be effective at the rec level. There's not the issue of exquistite timing wrapped into a vicious RHS swing that would be destroyed by actively snapping the wrist into contact.

Well, at an intermediate and onwards rec level, active snapping of the wrist would still mess up the timing. At the beginner level, you don't need a lag-and-release forehand; just hitting a smooth forehand would be a big deal.
 

Chas Tennis

G.O.A.T.
The whip is usually used as an analogy for the delayed arm, so before the impact.

I think of a whip as something that has lag and then builds and builds velocity and finally has an audible crack from the tip due to its very high velocity.

When I look at the forehand in high speed video I see accelerations with features but the forward racket head acceleration seems gradual and does not seem to have anything like the crack of a whip.

Is the "delayed arm" a term for the arm and racket inertia along with other forces that causes lag? The term 'lag' itself seems to refer to what is seen or seen in videos - no other information. But lag hides the inertia, muscle stretching, causes, etc that occur when you see lag. Maybe 'lag' is defined somewhere and these important details are included. ? Lag always has a few important things accompanying it that never seem to be discussed.
 
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Chas Tennis

G.O.A.T.
I can't move frame by frame in youtube, but as seen in your slow motion video, Dimitrov doesn't seem to snap his wrist. End of story for me and as someone else put it, amateurs shouldn't snap their wrists.

Stop the video. Now use the period "." and comma "," keys to single frame. Let us know if it works. I don't know about smart phones but my computer works great.

I did not know this Youtube feature for the last 5 years!!!! Somebody on the forum mentioned it, oh no!. I wasted a lot of time trying to stop on a particular frame over the last 5 years.......
 

Fintft

G.O.A.T.
I think of a whip as something that has lag and then builds and builds velocity and finally has an audible crack from the tip due to its very high velocity.

When I look at the forehand in high speed video I see accelerations with features but the forward racket head acceleration seems gradual and does not seem to have anything like the crack of a whip.

Is the "delayed arm" a term for the arm and racket inertia along with other forces that causes lag? The term 'lag' itself seems to refer to what is seen or seen in videos - no other information. But lag hides the inertia, muscle stretching, causes, etc that occur when you see lag. Maybe 'lag' is defined somewhere and these important details are included. ? Lag always has a few important things accompanying it that never seem to be discussed.


I'll let the experts answer you, but personally I'm focusing on doing the lag part of the whip (with a relaxed arm) and not the crack (except the part that happens naturally when the wrist moves from the initial laid back position), especially not when most coaches have told me to not forget about going more through the ball first, before coming over: e.g. the last drill used a week ago, to reinforce that was to try to hold the racquet for a second or two after the going through.

In Dimitrov's video I still don't see (even after going frame by frame) a wrist snap per say (it seems that the wrist and the forearm move together on the follow through- and to my lowly level this seems the right approach).
 

Fintft

G.O.A.T.
Stop the video. Now use the period "." and comma "," keys to single frame. Let us know if it works. I don't know about smart phones but my computer works great.

I did not know this Youtube feature for the last 5 years!!!! Somebody on the forum mentioned it, oh no!. I wasted a lot of time trying to stop on a particular frame over the last 5 years.......
Thanks it works.
 

JohnYandell

Hall of Fame
The argument that will never end!

A question to consider about the "movement" of the wrist in the forward swing: Why does it vary? On an inside out ball there is much less flexion than on a crosscourt. Another question why does the wrist flex backwards the opposite way to a more laid back position on many balls?
Whatever the answers (except for extreme western grips like Sock) the wrist is laid back before during and after contact on the vast majority of all forehands. That's the takeaway for everyone here--though again the advocates of conscious forward snap are seemingly infinite. So many working teaching pros casually advocate this and so the thought is perpetuated and will probably always be.

Consider the research of Brian Gordon. Naturally the wrist wants to come around during the forward swing. But Brian's research shows that players are actively inhibiting this. Correct they are reducing the amount of flexion--even though yes the measurements show flexion obviously contributes to racket speed.

Why? Because of shot line. The angle of the wrist influences the angle of the racket head at contact. The angle of the racket head at contact influences the line of the shot. If you can't inhibit the wrist flex you cannot develop shot control. Do good players do this consciously? No way. Do they feel the relation between the racket head and the shot line? Yes.
 

Chas Tennis

G.O.A.T.
................especially not when most coaches have told me to not forget about going more through the ball first, before coming over: e.g. the last drill used a week ago, to reinforce that was to try to hold the racquet for a second or two after the going through.
.................

I don't know much about teaching, drills and progressions.

For Dimitrov's straight arm forearm topspin drive from those 2014 forehands, it looks as if the racket path provides most of the upward racket motion for topspin, possibly with a little ISR (his wrist band rotates up a little). That upward path starts well before impact. The amount of ISR used for topspin probably varies among Dimitrov's forehands and certainly among other players, especially with more windshield wiper forehands. There's variety. This is something that is clear in high speed videos.

Just read John Yandell's post, with more detail on the finer points of racket control. At this point, I mostly look at where the racket head speed comes from leading to impact and post on that.

The purpose of the follow through is to slow the body, arm and racket down. To do this the players might stay relaxed and let the joint structures of the body stop the arm. But they could also be activating muscles that could slow down, or drag on the arm motion. ? There is probably more than one way to do a follow through, for each stroke and speed, so I find it difficult to interpret how the body and racket move as seen in high speed videos, especially serve follow throughs. Where the ball impacts the racket also affects the follow through.
 
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Fintft

G.O.A.T.
Just read John Yandell's post, with more detail on the finer points of racket control. At this point, I mostly look at where the racket head speed comes from leading to impact and post on that.

I agree of course with John Yandell's post as for your question about racquet head speed, imho it comes from the:
  1. Arm lag/whip
  2. But also from the follow-through
The purpose of the follow through is to slow the body, arm and racket down. To do this the players might stay relaxed and let the joint structures of the body stop the arm. But they could also be activating muscles that could slow down, or drag on the arm motion. ?

Uhm, no, imho! The purpose of the follow through is rather:

  1. Spin (be it side spin and/or topspin)
  2. Speed/power
 

GuyClinch

Legend
Yandell is right..


You could be right there. How do you see it working?

Doesn't seem complicated to me - its just the monkey drum analogy.

Racquet has weight - racquet has inertia. So when body rotates arm and racquet lag behind. When racquet lags behind wrist lays back. After or a bit before arm slows down (after contact or slighty before) - racquet will catch up and surpass arm - hence angle change of wrist.

I'd love to be able to spell out the physics equations but I skipped physics in HS. But you can just shadow this yourself in about 5 seconds.. So you can see the physics make sense. Add more weight to your racquet (slide a tennis ball into the center) and you can feel the effect even more.

Incidentally same idea on the serve - the racquet drop in part is essentially letting the racquet say behind - while your body rotates forward and upward..

Anyway if you see it this way you can see why Yandell is right - wrist gets laid back on modern forehand because of lag - and because your swing doesn't slow to much before contact - it stays laid back to some degree.

If you just go ahead and stop your arm before contact - but keep your wrist relaxed racquet will want to keep going and your wrist angle will change 'early'.

This is not how you hit a forehand but shows the concept.
 

Fintft

G.O.A.T.
Great post as usual:

... Naturally the wrist wants to come around during the forward swing. But Brian's research shows that players are actively inhibiting this. Correct they are reducing the amount of flexion--even though yes the measurements show flexion obviously contributes to racket speed.

Why? Because of shot line. The angle of the wrist influences the angle of the racket head at contact. The angle of the racket head at contact influences the line of the shot. If you can't inhibit the wrist flex you cannot develop shot control. Do good players do this consciously? No way. Do they feel the relation between the racket head and the shot line? Yes.

Isn't it why good players try to go through the ball first before "coming around during the forward swing"? E.g. a coach told me to imagine going through 3-4 aligned first, before coming around.
 

GuyClinch

Legend
I think if you look at slow motion you can see what I mean on both sides - after contact wrist angle changes but before contact lag lets the racquet lay back..

This works on forehand and backhand..


I see it as more that tennis pros illustrate the concept of inertia - not of active use of wrist to provide power..
Great post as usual:



Isn't it why good players try to go through the ball first before "coming around during the forward swing"? E.g. a coach told me to imagine going through 3-4 aligned first, before coming around.
 

Chas Tennis

G.O.A.T.
It seems like the OP was backing off of the word "snap" after posts #5 and #7.
Let's remove the "snap" word and call it "super fast wrist-forearm pronation" which looks like a snap...

To salvage some of our time studying the details here is a second Dimitrov forehand(2014) question -

Based on this video, how is Dimitrov rotating his hips, what leg actions, etc?

......................
Rob Cherry Essential Tennis close up clearly showing the wrist joint motions on the forehand.
http://robcherrytennis.com/grigor-d...motion-forehand-1-western-southern-open-2014/
...............................
2) How much internal shoulder rotation (ISR) occurs before impact? Does it contribute to forward racket head speed?
..........................................
To do single frame on Youtube use the "." & "," keys.
.........................................................

Would you call these Dimitrov forehands more of the 'weight shift' forward type or the 'body rotation' type?

How does this relate to lag?
 
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JohnYandell

Hall of Fame
Fin,
Yes that's why that's a good analogy even though the racket is actually moving on a 3D curve--but it aligns the shape of the curve and the shot line and helps to control the wrist.
Guy,
If I am right it's only because I listened to Brian and saw the proof of his concept in Tennisplayer video. Explained a lot of the variations!
 
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Fintft

G.O.A.T.
Fin,
Yes that's why that's a good analogy even though the racket is actually moving on a 3D curve--but it aligns the shape of the curve and the shot line and helps to control the wrist.
Guy,
If I am right it's only because I listened to Brian and saw the proof of his concept in the video. Explained a lot of the variations!

Hi John,

Thanks I do remember reading your posts about the 3D curve + also what the best coach I work a few days over the last few summers (in Europe) said about hitting the ball from the side even on the FH (initially he told me to do that on the 1H BH - from the left side and low to high)
 

TennisCJC

Legend
I think if you look at slow motion you can see what I mean on both sides - after contact wrist angle changes but before contact lag lets the racquet lay back..

This works on forehand and backhand..


I see it as more that tennis pros illustrate the concept of inertia - not of active use of wrist to provide power..

Look at the FH around 1:28-1:30. You can see the wrist is laid back before, during and after contact. You can also see that the forearm windshield wiper action is happening after the ball is long gone. This is a model for rec players. Get the wrist laid back as you start forward, don't actively muck with your wrist around contact instead just use the angle to control direction (as JYandell says) and let the follow through flow into the wiper finish primarily as a function of comfort and flow. Don't try to go from laid back wrist to flex forward wrist in your FH or in your thought process as that is going to give you an inconsistent FH. Don't try to use windshield wiper action right at contact instead think of it as part of a smooth follow through. You will be much better off taking any active action of the wrist out of your FH rather than putting it into your FH.
 

GuyClinch

Legend
Look at the FH around 1:28-1:30. You can see the wrist is laid back before, during and after contact. You can also see that the forearm windshield wiper action is happening after the ball is long gone. This is a model for rec players. Get the wrist laid back as you start forward, don't actively muck with your wrist around contact instead just use the angle to control direction (as JYandell says) and let the follow through flow into the wiper finish primarily as a function of comfort and flow. Don't try to go from laid back wrist to flex forward wrist in your FH or in your thought process as that is going to give you an inconsistent FH. Don't try to use windshield wiper action right at contact instead think of it as part of a smooth follow through. You will be much better off taking any active action of the wrist out of your FH rather than putting it into your FH.

You don't have to lock the wrist fully laid back to start though. Like other pros I lay it back a little in the ready position and let momentum do the rest. That being said I have tried out one of those wrist straps that pin your wrist back in a fully laid back position and can hit good forehands that way - so both methods work..

Also FWIW OP was interested in what Grigor is doing - not what rec players do. You can serve great underhanded - win matches. Doesn't mean that's how pros do it..
 

Chas Tennis

G.O.A.T.
1:28-1:30 from post #45.

Look at the FH around 1:28-1:30. You can see the wrist is laid back before, during and after contact. You can also see that the forearm windshield wiper action is happening after the ball is long gone. This is a model for rec players. Get the wrist laid back as you start forward, don't actively muck with your wrist around contact instead just use the angle to control direction (as JYandell says) and let the follow through flow into the wiper finish primarily as a function of comfort and flow. Don't try to go from laid back wrist to flex forward wrist in your FH or in your thought process as that is going to give you an inconsistent FH. Don't try to use windshield wiper action right at contact instead think of it as part of a smooth follow through. You will be much better off taking any active action of the wrist out of your FH rather than putting it into your FH.

How can you be confident that wrist flexor muscles are not providing forces by passive means - by stretched muscles shortening?

Or by active flexor muscle forces involving Actin & Myosin, that are stimulated by EMG signals?

Or is the angle of the forearm and racket 'inhibited' by forces from wrist extensor muscles (the antagonist muscles of the wrist flexors).

The windshield wiper using ISR has to occur during impact to make any difference to the forehand drive's topspin.

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Consider the research of Brian Gordon. Naturally the wrist wants to come around during the forward swing. But Brian's research shows that players are actively inhibiting this. Correct they are reducing the amount of flexion--even though yes the measurements show flexion obviously contributes to racket speed.
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Is this research published and available? EMG signals to the extensor muscles? Or 3D motion capture system measurements?

There are lots of possibilities and probably significant variations among pro players with successful forehands. The list of options for topspin forehand drives aimed at the same spot of the court inlcludes:

1) racket path
2) windshield wiper effects to some degree before or during impact but not after.
3) overall body rotation rate and resulting centrifugal force history
4) bent elbow or straight arm (Dimetrov 2014 straight)
5) Eastern Forehand Grip (Dimetrov 2014), Semi Western or other
6) accelerations of upper body turn, shoulder joint motions, wrist, etc.
7) others

There is evidence of successful topspin forehands that shows a lot of variety. The forehands all use the same principles such as the stretch shorten cycle, lag, upper body turn, but there are variations. Muscle forces are difficult to confirm in videos. See Sock forehand videos.

If all that were described for each current forehand technique then the finer points being used for aiming have still to be considered.
 
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ChaelAZ

G.O.A.T.
Should have been termed something like 'Lag and whip or stroke' back when it started getting popular a few years back.
TT people hate the term snap.
 

JohnYandell

Hall of Fame
I don't even like lag. If the backswing is reasonable and the start of the foreswing is reasonable, you will lag if you are a high level player probably without even knowing it and certainly without thinking about it.
For most players it's far better at first to consciously set up the wrist back position--and get the core fundamentals right.
It's crazy the time and energy (and posts and words) people waste on this bogus lag and snap concept. Then you see their forehands and it's horrifying because the preparation and the extension are limited, wrong, or non-existent.
No doubt the motions on the forehand are complex and varied--the mistake is in confusing effects with causes and getting lost trying to manipulate the effects.
 
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