Dead spot for ultra fast forehands

Smecz

Semi-Pro
Hello

We are constantly told to hit the sweet spot of the racket, for safety and a clean hit.

However, as it relates to the generation of power and ball speed, I watched videos with the fastest ATP forehands, and there a lot of forehands are hit dead spot.!!!


Hitting from a dead spot may be more risky and dangerous, but isn't the speed of the ball during the match crucial...

Thanks to hitting the dead spot, I close the head of the racket faster and faster and more violently, then in the dead spot I have a chance to reach the ball as quickly as possible!!!

Or maybe we shouldn't always hit the sweet spot so much, but also hit the more risky dead spot, in moments when you feel it's worth it:





The videos with the Fastest Monfils and Haase forehands explains what I mean, it shows Gael and Haase hitting a dead spot...

Shouldn't we tennis players hit the dead spot of the racket more often, instead of always hitting the sweet spot?!

For power generation from the forehands?!
 
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Chas Tennis

G.O.A.T.
My standard for knowing things about tennis strokes is high speed videos of current ATP players. Seeing where the ball hits on a racket face in internet videos takes some time and you need to view a sample of players. I have not done much of that.

The only thing that I studied briefly was relative to centerline of the racket, I thought that the ball was usually impacting lower than the centerline of the racket face on average. I looked at some impacts and they were closer to centerline than I expected. So I stopped looking any farther for that issue. The thread with my posts was posted and Toly was involved in the thread.

I usually do what I call, 'quick stats', view about 10 clear high speed videos randomly selected, that show the issue. If I see most doing something I assume it might be true and do it more carefully and count more or not. To do it right the resulting shot of the ATP player, in or out, type of shot, under stress or not, high or low, other conditions, should be known and limited. Those things are hardly ever known when searching strokes on the internet. It takes a lot of time to find suitable videos and I have not done that properly on any issue. To identify a sub-motion is not so difficult as the spot on a racket face. Some Love Tennis footage from behind would show what you are after on the racket face - the hardest thing to find videos for is the location of the ball on the racket face, why don't you try and see what you can find. "Compilations" of forehands from behind have for example, many ATP forehands.......

My observation - Most serves are struck in the top half of the racket. Check that out by finding and looking at 20 serves.

I also have not paid much attention to sweet spot and dead spot etc. where the ball hits on the face. I have never seen video observation experiments and resulting ball trajectories.

In other words, it takes too much time to study the location of impact spots on the racket face.

On the other hand, I looked into topspin drives by ATP players and found that the racket face was tilted forward many degrees. I also found the Tennisspeed Blog article about Djokovic's forehand with clear evidence of the closed forward tilt and so I believe in the closed tilt for ATP drives. I also studied closed racket faces for the kick serve impact and believe that by a few of my own videos and some ATP serves identified as kick serve on the internet. If I had one player that could hit a strong kick serve with the side bounce, I could get videos that confirm the tilt of the racket for the kick serve. Posted several times, See thread Junior Twist Serve. If you look carefully every time that you can see the racket face tilt on a drive, you soon see that the closed tilt is usually done for ATP top spin drives. You have to specify always specify the stroke.

Sorry, I don't have any information on sweet spots and dead spots. Go to Google Scholar and search for biomechanics studies on the racket face locations. Also, I saw a lot of discussions of sweet spots in the 1970s and never saw tests or high speed films on spots hit on the racket face and results. Some may have been done. ? But in those days they did not even know that the high level serve involved ISR, and that was clearly seen in high speed imaging. High speed film cameras were very expensive in the 1970s, film and processing film were expensive and only researchers studied tennis stokes with film. That's one reason why ISR was not confirmed by tennis researchers until 1995. Vic Braden was very active in high speed film imaging in the 1970's.

What you are interested in is easy to do - if you know the stroke technique - with a high speed video camera. I recommend the Casio Ex-FH100 and have bought one used on **** for $85. It will show you where the ball hits on the racket face. You could mark the racket sweet spot and dead spot with Sharpies and observe the effect of sweet spot or dead spot hits on the shots.

Will look at videos later.
 
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Rosstour

G.O.A.T.
The real takeaway here is that the key to really fast forehands is to hit them close to the body. The further out you go, the harder it is to get the most violent unit turns
 

Chas Tennis

G.O.A.T.
The real takeaway here is that the key to really fast forehands is to hit them close to the body. The further out you go, the harder it is to get the most violent unit turns

Rotation Rate & Radius Out

The racket head forward speed would be

Rotation rate (in radians per second) for each axis X distance out from each rotation axis

1) Spine Axis Rotation Rate X Radius Out from Spine to Racket head
PLUS
2) Shoulder Joint Axis Rotation Rate X Radius Out from SJ to Racket head

The radius out gets shorter for "close to the body".

The moment of inertia (MOI) increases as masses like the arm and racket are moved out from the body or shoulder joint. MOI is resistance to rotation and it may slow the rotation rate depending on strength. ?

If you have the strength, the farther out from the axis of rotation the higher the racket head speed.
 
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Rosstour

G.O.A.T.
The racket head forward speed would be

Rotation rate (in radians per second) for each axis X distance out from each rotation axis

1) Spine Rotation Axis Rate X Radius out from Spine to Racket head
PLUS
2) Shoulder Joint Axis Rate X Radius Out from SJ to Racket head

The radius out gets shorter for close to the body. The moment of inertia increases as masses like the arm and racket are moved out form the body. MOI is resistance to rotation and it may slow the rotation rate depending on strength. ?

Whoa bro that's too much for this pea brain

i just know that I spin faster in the air (trampolines etc) when my arms are closer to the body and I apply the same principle to tennis
 

SystemicAnomaly

Bionic Poster
Whoa bro that's too much for this pea brain

i just know that I spin faster in the air (trampolines etc) when my arms are closer to the body and I apply the same principle to tennis
Initially, the racket arm Is fairly close to the body to facilitate torso rotation. We see this both on serves and on groundstrokes. However, as the forward or upward swing continues, the arm and racket is extended to achieve a faster RHS. However, the off arm is tucked in or pulled closer to the body, prior to contact to facilitate body rotation.

When the racket head is moving through an arc, especially on first serves and on fast groundstrokes, the dead spot will be moving much faster than the sweet spot.

On volleys and on other strokes where the racket is moving more linear than through an arc, it makes sense to hit close to the sweet spot rather than the dead zone
 
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Smecz

Semi-Pro
My standard for knowing things about tennis strokes is high speed videos of current ATP players. Seeing where the ball hits on a racket face in internet videos takes some time and you need to view a sample of players. I have not done much of that.

The only thing that I studied briefly was relative to centerline of the racket, I thought that the ball was usually impacting lower than the centerline of the racket face on average. I looked at some impacts and they were closer to centerline than I expected. So I stopped looking and farther for that issue. The thread with my posts was posted and Toly was involved in the thread.

I usually do what I call, 'quick stats', view about 10 clear high speed videos randomly selected, that show the issue. If I see most doing something I assume it might be true and do it more carefully and count more or not. To do it right the resulting shot of the ATP player, in or out, type of shot, under stress or not, high or low, other conditions, should be known and limited. Those things are hardly ever known when searching strokes on the internet. It takes a lot of time to find suitable videos and I have not done that properly on any issue. To identify a sub-motion is not so difficult as the spot on a racket face. Some Love Tennis footage from behind would show what you are after on the racket face - the hardest thing to find videos for is the location of the ball on the racket face, why don't you try and see what you can find. "Compilations" of forehands from behind have for example, many ATP forehands.......

My observation - Most serves are struck in the top half of the racket. Check that out by finding and looking at 20 serves.

I also have not paid much attention to sweet spot and dead spot etc. where the ball hits on the face. I have never seen video observation experiments and resulting ball trajectories.

In other words, it takes too much time to study the location of impact spots on the racket face.

On the other hand, I looked into topspin drives by ATP players and found that the racket face was tilted forward many degrees. I also found the Tennisspeed Blog article about Djokovic's forehand with clear evidence of the closed forward tilt and so I believe in the closed tilt for ATP drives. I also studied closed racket faces for the kick serve impact and believe that by a few on my own videos and some serve identified as kick serve on the internet. If I had one player that could hit a strong kick serve with the side bounce I could get videos. If you look carefully every time that you can see the racket face tilt on a drive, you soon see that the closed tilt is done more for top spin drives. You have to specify the stroke.

Sorry, I don't have any information on sweet spots and dead spots. Go to Google Scholar and search for biomechanics studies on the racket face locations. Also I saw a lot of discussions of sweet spots in the 1970s and never saw tests or high speed films on spots hit on the racket face. Some may have been done. But in those days they did not even know that the high level serve involved ISR, and that was clearly seen in high speed imaging. High speed film cameras were very expensive in the 1970s, film and processing film was expensive and only researchers studied stokes with film. That's one reason why ISR was not confirmed by tennis researchers until 1995. Vic Braden was very active in high speed film imaging in the 1970's.

What you are interested in is easy to do, if you know the stroke technique, with a high speed video camera. I recommend the Casio Ex-FH100 and have bought one used on **** for $85. It will show you where the ball hits on the racket face. You could mark the sweet spot and dead spot with Sharpie's and observe the effect sweet spot or dead spot has on your strokes.

Will look at videos later.
A lot of correct informations,I'd have to study it ;)

Such information would certainly be useful for the fastest forehand Atp, observations of ball bounce points.

I found one article in google schoolar:


There is such information about dead spot:

It is shown that a tennis racket has a dead spot, but it does not have a well-defined sweet spot, when measured in terms of the rebound of a tennis ball. A ball dropped onto the center of the strings bounces to about 30% its original height. The bounce is much weaker near the tip of the racket, being almost zero at the dead spot. These effects are explained in terms of the effective mass and rotational inertia of the racket, and by reference to the behavior of other cantilevered beams. It is concluded, somewhat paradoxically, that the best place to hit a serve or smash is at the dead spot.

Does it work for smash and serve but not forehand?:unsure:


What makes me wonder is that if hitting the dead spot, i.e. near the tip, has lower energy than the sweet spot, how come Monfils hit the dead spot at 199 km/h?!



I've watched it a dozen times and I still see Gael's forehand and the ball hit in the dead spot!!

Such a hit closest to the tip of the racket at 12 o'clock causes us to reach the ball faster from the front and we are stretched as far forward as possible.!!

And then a shot like Monfils with a forehand of 199 km/h makes sense!!!

Besides, I would also consider this a sweet spot, because the racket used was the Wilson Pro Staff 85,
and with such a racket it's easier to hit beyond the sweet spot...
 

Dragy

Legend
Fastest acceleration will happen with use of what is called kinetic chain, and you can also look at this as pitching mechanics, similar to serve. Rock skipping motion as well. Just consider another segment/pendulum being the racquet, so you go for peak racquet head speed, not peak hand speed. The sequence appears just a tad longer.

PS you actually get “hand” as a segment with pitching/rock skipping, it’s just way shorter with lower momentum of inertia than racquet.
 

travlerajm

Talk Tennis Guru
The real takeaway here is that the key to really fast forehands is to hit them close to the body. The further out you go, the harder it is to get the most violent unit turns
But Rafa can hit them pretty fast too even though his contact point is far away from the body?
 

Rosstour

G.O.A.T.
But Rafa can hit them pretty fast too even though his contact point is far away from the body?

What's his fastest ever?

Monfils has hit them into the 120s and usually with a very bent arm and close contact

Murray holds/held the record for fastest FH ever and he also hits close to his body. No doubt he was using his opponent's pace in his favor on that shot
 

travlerajm

Talk Tennis Guru
What's his fastest ever?

Monfils has hit them into the 120s and usually with a very bent arm and close contact

Murray holds/held the record for fastest FH ever and he also hits close to his body. No doubt he was using his opponent's pace in his favor on that shot
For Rafa, we would have to take the velocity plus rpm together to calculate the total kinetic energy in the ball and then convert it to the velocity that it would have been had he hit it with a flatter trajectory.
 

Rosstour

G.O.A.T.
For Rafa, we would have to take the velocity plus rpm together to calculate the total kinetic energy in the ball and then convert it to the velocity that it would have been had he hit it with a flatter trajectory.

Now you're changing the discussion to suit one player. Not at all interested in arguing the best FH
 

SystemicAnomaly

Bionic Poster
What's his fastest ever?

Monfils has hit them into the 120s and usually with a very bent arm and close contact

Murray holds/held the record for fastest FH ever and he also hits close to his body. No doubt he was using his opponent's pace in his favor on that shot
Andy, like Novak hits the Fh with a bent elbow. Less bent on high CP than low CP. Even so, his racket is further from his body at contact that it is when he starts his uncoiling
 

SystemicAnomaly

Bionic Poster
Murray crushes the ball, hits the highest jump of the ball and also hits the dead spot.

He hits the forehand inside out, actually turns his hand close to the body and intuitively hits the dead spot.

This way the ball quickly disappears from the string... :)
Typical dwell times for a tennis ball on strings is 4-5 ms. Longer dwell times are possible for very low string tensions. Hitting the ball very hard will effectively stiffen the stringbed. But even then, I can’t imagine that the dwell time is much less than 4 ms.

Perhaps still significantly greater than 3.5 ms. Just a guess tho. Don’t know that this has ever been measured accurately.

At higher speeds, the ball will deform more on impact. The strings will likely give a bit more as well and the ball will be deep pocketed to a greater degree into the stringbed. The extra deformations will still take time. Because of all this, I don’t believe it will reduce dwell time much less than 4 ms
 

Dragy

Legend
Regarding Andy Murray...

You guys know the theory behind "dead spot", don't you? It's the spot on the stringbed, where if racquet was static, and ball fell vertically at this spot, the ball would stop completely, while racquet head would be (initially) pushed back. It's a spot, theoretically, where "effective mass" of racquet hoop matches ball mass. And hence they both act like billiard balls hit head-on.

Why is this important? The theory says, when the ball is static, it's enough to use the spot where effective mass is equal to ball mass to transfer max energy. Going lower in stringbed should make no sense, as there's no benefit for impact of increased "effective mass" over the ball mass, while loosing RHS.

This only works with no-speed incoming ball, as otherwise racquet gets pushed back to a degree, and with 4ms dwell time this may alter the outcome significantly. Also, some importance is in how strings/ball/frame deform dependent on the speeds of ball and RHS, but let's neglect it so far.

Bored yet? We're getting to it!

Murray uses 380 SW racquet. Compared to your typical retail 320 SW racquet this equals to adding at least 20g of lead in the hoop. Which is 1/3 of ball mass. So now, where you would have dead spot on typical retail frame (effective mass = x1 of ball mass) you now have at least x1.33 of ball mass. The real "dead spot" of Murray's racquet is even closer to the tip. But you don't want to use it against incoming pace! You actually want your racquet to dominate the collision.

What to get here for yourself? If you are using 320-330 SW racquet and want to counterpunch high pace incoming ball, you better use middle of the stringbed. If under your bumper guard is a huge colony of lead tape, you may go with impact zone closer to the tip ;)

PS Bonus tip: if you wish to handle and redirect pace with control rather than break speed records, you can benefit from using more stable, "plowing" spot around 18-19 inch, closer to the dampener zone.
 

Smecz

Semi-Pro
Typical dwell times for a tennis ball on strings is 4-5 ms. Longer dwell times are possible for very low string tensions. Hitting the ball very hard will effectively stiffen the stringbed. But even then, I can’t imagine that the dwell time is much less than 4 ms.

Perhaps still significantly greater than 3.5 ms. Just a guess tho. Don’t know that this has ever been measured accurately.

At higher speeds, the ball will deform more on impact. The strings will likely give a bit more as well and the ball will be deep pocketed to a greater degree into the stringbed. The extra deformations will still take time. Because of all this, I don’t believe it will reduce dwell time much less than 4 ms
It is possible that the body rotation that Haase and Monfils make with these forehands in the videos causes them to hit the dead spot.

It's just that the head of the racket closes so quickly and additionally they run away to the left side, which causes them to hit a dead spot.!!

This way of swing means that you can't control the head or the place of impact too much...
 

Grafil Injection

Hall of Fame
The typical contact point on modern rackets is around 1/2 inch above the north-south centre, because hoops are tear-drop shaped. Racket stencils are even skewed slightly upwards like that, so you can use them as targets. This point corresponds to the widest part of the hoop, and is where manufacturers put PWS etc. So on all shots players are actually hitting slightly higher than the middle, and that feels sweet. All of the super-fast shots shown are inside-out / flat forehands (even Kyrios' cross-court). When you do an inside-out, you pull your body away from the racket to create maximum (but very fast) lag and hold the face open as long as possible. This inevitably means you contact even higher on the face than normal and you get side-spin L to R for a RHer. The contact may hence correspond with the 'dead-point', but I doubt players purposefully aim to hit high on the hoop, it's just a natural occurence for an inside-out 'slap' shot that requires no vertical path for the racket, just rotation around the body.
 

Chas Tennis

G.O.A.T.
Whoa bro that's too much for this pea brain

i just know that I spin faster in the air (trampolines etc) when my arms are closer to the body and I apply the same principle to tennis
You don't hit the ball with your body but the racket head.

There is another thing called parametric amplification??? (known in golf also) where pulling the arm in can speed up certain parts.
 
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Chas Tennis

G.O.A.T.
Typical dwell times for a tennis ball on strings is 4-5 ms. Longer dwell times are possible for very low string tensions. Hitting the ball very hard will effectively stiffen the stringbed. But even then, I can’t imagine that the dwell time is much less than 4 ms.

Perhaps still significantly greater than 3.5 ms. Just a guess tho. Don’t know that this has ever been measured accurately.

At higher speeds, the ball will deform more on impact. The strings will likely give a bit more as well and the ball will be deep pocketed to a greater degree into the stringbed. The extra deformations will still take time. Because of all this, I don’t believe it will reduce dwell time much less than 4 ms
Toly posted this. I miss Toly and his great posts, with composite pictures and videos.
To single frame on Youtube, stop video, go full screen and use the period & comma keys.

If the camera speed was actually 6,000 frames per second, then 6 frames would equal 1 millisecond. 4 milliseconds would be 24 clicks of the period and 5 milliseconds would be 30 clicks.

You can count frames and make a time line that shows ball deformation, string deformation, first touch to last touch VS time. Please post if you do.

-------------------------------------------------------------------------------------------------------------------------------------
Time in milliseconds and the time = 0 at first touch of ball or closest to impact is a good time scale for fast tennis motions.

Video application Kinovea, free open source, has a countdown time mode where the milliseconds shown on each frame indicate the time before first touch or impact.
 
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Smecz

Semi-Pro
Regarding Andy Murray...

You guys know the theory behind "dead spot", don't you? It's the spot on the stringbed, where if racquet was static, and ball fell vertically at this spot, the ball would stop completely, while racquet head would be (initially) pushed back. It's a spot, theoretically, where "effective mass" of racquet hoop matches ball mass. And hence they both act like billiard balls hit head-on.

Why is this important? The theory says, when the ball is static, it's enough to use the spot where effective mass is equal to ball mass to transfer max energy. Going lower in stringbed should make no sense, as there's no benefit for impact of increased "effective mass" over the ball mass, while loosing RHS.

This only works with no-speed incoming ball, as otherwise racquet gets pushed back to a degree, and with 4ms dwell time this may alter the outcome significantly. Also, some importance is in how strings/ball/frame deform dependent on the speeds of ball and RHS, but let's neglect it so far.

Bored yet? We're getting to it!

Murray uses 380 SW racquet. Compared to your typical retail 320 SW racquet this equals to adding at least 20g of lead in the hoop. Which is 1/3 of ball mass. So now, where you would have dead spot on typical retail frame (effective mass = x1 of ball mass) you now have at least x1.33 of ball mass. The real "dead spot" of Murray's racquet is even closer to the tip. But you don't want to use it against incoming pace! You actually want your racquet to dominate the collision.

What to get here for yourself? If you are using 320-330 SW racquet and want to counterpunch high pace incoming ball, you better use middle of the stringbed. If under your bumper guard is a huge colony of lead tape, you may go with impact zone closer to the tip ;)

PS Bonus tip: if you wish to handle and redirect pace with control rather than break speed records, you can benefit from using more stable, "plowing" spot around 18-19 inch, closer to the dampener zone.
That's interesting, because Federer has
a lot of lead at the 12 o'clock position of the racket.

Does that mean it can have an impact zone closer to the dead center?!

With this arrangement, the rocket definitely moves forward more and gives more power...

I also take into account that if a given player has a lead under the tip of the racket at 12 o'clock, he can naturally hit the dead spot..

I don't know the specifications of Monfils and Haase rackets, maybe they are similar too...?!
 

Dragy

Legend
That's interesting, because Federer has
a lot of lead at the 12 o'clock position of the racket.
Federer has been using lower SW compared to Murray, Nadal and Djokovic. Monfils reported to have huge (386) SW as well.

The point is, oldschool pro racquet weights make the "deadspot theory" not applicable. But it makes upper hoop much more playable than what you have in no-tech traditional retail frames. If you can accelerate 360-380 SW stick.
 

Chas Tennis

G.O.A.T.
Hello

We are constantly told to hit the sweet spot of the racket, for safety and a clean hit.

However, as it relates to the generation of power and ball speed, I watched videos with the fastest ATP forehands, and there a lot of forehands are hit dead spot.!!!


Hitting from a dead spot may be more risky and dangerous, but isn't the speed of the ball during the match crucial...

Thanks to hitting the dead spot, I close the head of the racket faster and faster and more violently, then in the dead spot I have a chance to reach the ball as quickly as possible!!!

Or maybe we shouldn't always hit the sweet spot so much, but also hit the more risky dead spot, in moments when you feel it's worth it:





The videos with the Fastest Monfils and Haase forehands explains what I mean, it shows Gael and Haase hitting a dead spot...

Shouldn't we tennis players hit the dead spot of the racket more often, instead of always hitting the sweet spot?!

For power generation from the forehands?!

There is too much motion blur and the recording speed is too slow to tell where the ball was hit on the racket face at 13 seconds in the Monfils video.

Starts at 12 seconds for the first playback.
 

Yamin

Hall of Fame
Yes high swing weight opens up the tip, swing speed increases, and then ball goes fast (if you can swing it).

Polarized setup with high swing weight and a fast arm will give you the most max power.

Most rackets today are designed for slow swings, "static stability" (higher twist weight) and have absolutely dead tips for the purpose of control that are often harsh and jarring.

My V7 blade gives me more top end power than any other racket off the shelf.
 
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Dragy

Legend
Does anyone even use the bottom of the hoop?
Yes, of course, the part below geometrical center is quite in use.

Why not smaller head? Forgiveness as well as strings length to produce action + power.

What you do using the upper part of stringbed some other solve by using xl racquets. But on average, 27 in long racquets are optimal for adult tennis. Sweetspot of such a racquet in modern game is expanded somewhere between 20-23 in from the buttcap.
 

SystemicAnomaly

Bionic Poster
Whoa bro that's too much for this pea brain

i just know that I spin faster in the air (trampolines etc) when my arms are closer to the body and I apply the same principle to tennis
When the arms & legs are pulled close to the (longitudinal) axis, the rotational inertia (MOI) about that axis is reduced. This allows for a greater angular velocity (faster spins). This is quite evident when we watch an ice skater spin. When they pull in their arms and leg(s), their rotational spin increases quite dramatically.

This concept is used in overhand ball throwing and in many strokes in tennis. But not entirely the way you suggest. When the torso/body starts to uncoil, the racket hand and racket head are quite close to the body. Even at the commencement of the forward or upward (serve) swing, the hand & racket head is still fairly close to the body. This allows as to quickly pick up rotational speed.

As that swing continues & the body is uncoiling more quickly, the racket head moves away from the body in order to contact the ball somewhat further from the body. But this increase in the distance of the racket head from the body is offset by the action of the opposite arm.

On the serve, the tossing arm is tucked into the body as the racket head moves upward & away from the body. On a Fh g'stroke, the off arm is often fully extended (to the side) before the body begins to uncoil. As the forward swing is underway, that off arm is pulled somewhat closer to the body. This will help to offset the extension of the racket arm and racket away from the body.
 

Dragy

Legend
When the arms & legs are pulled close to the (longitudinal) axis, the rotational inertia (MOI) about that axis is reduced. This allows for a greater angular velocity (faster spins). This is quite evident when we watch an ice skater spin. When they pull in their arms and leg(s), their rotational spin increases quite dramatically.

This concept is used in overhand ball throwing and in many strokes in tennis. But not entirely the way you suggest. When the torso/body starts to uncoil, the racket hand and racket head are quite close to the body. Even at the commencement of the forward or upward (serve) swing, the hand & racket head is still fairly close to the body. This allows as to quickly pick up rotational speed.

As that swing continues & the body is uncoiling more quickly, the racket head moves away from the body in order to contact the ball somewhat further from the body. But this increase in the distance of the racket head from the body is offset by the action of the opposite arm.

On the serve, the tossing arm is tucked into the body as the racket head moves upward & away from the body. On a Fh g'stroke, the off arm is often fully extended (to the side) before the body begins to uncoil. As the forward swing is underway, that off arm is pulled somewhat closer to the body. This will help to offset the extension of the racket arm and racket away from the body.
I’m not sure about the part with starting with arms close in, quite the opposite:

Screen-Shot-2022-04-02-at-5.28.47-PM.png


On serve - off-arm extended, hitting side elbow away from rotation axis.

This - having parts away - actually allows to build up bigger momentum through initial part of stroke. You don’t need to make it shorter in time, you have plenty. Then, by tucking off-arm in, you convert this momentum into faster torso rotation, that’s 100% true.

What we do with hitting arm, as far as I believe, is mostly subject to:
- creating efficient linkage to transfer energy without loss
- enhancing muscle stretch-shorten cycles work
- shaping the swing to your intent
 

SystemicAnomaly

Bionic Poster
I’m not sure about the part with starting with arms close in, quite the opposite:

Screen-Shot-2022-04-02-at-5.28.47-PM.png


On serve - off-arm extended, hitting side elbow away from rotation axis.

This - having parts away - actually allows to build up bigger momentum through initial part of stroke. You don’t need to make it shorter in time, you have plenty. Then, by tucking off-arm in, you convert this momentum into faster torso rotation, that’s 100% true.

What we do with hitting arm, as far as I believe, is mostly subject to:
- creating efficient linkage to transfer energy without loss
- enhancing muscle stretch-shorten cycles work
- shaping the swing to your intent
Not quite sure what you're saying

Carlos has not yet started his (post-unit turn) racket drop or his uncoiling action in the image you posted. He (fully) extends his left arm shortly after this. He doesn't seem to keep it extended to the side (fence) quite as long as others I've studied. He does have it bent again late in his drop as he starts to uncoil. It remains bent as his uncoil speed increases

Don't follow what you are trying to say about the serve. The tossing arm is fully extended during the trophy phase. It starts to come down as the racket is dropped and starts to pick up a bit speed. As the racket is dropping, it is fairly close to the body. As this happens, the cartwheel (shoulder-over-shoulder) action and uncoiling of the torso commence.

The tossing arm is tucked into the body as the racket arm & racket extends upward to contact the ball.
 

Dragy

Legend
Not quite sure what you're saying

Carlos has not yet started his (post-unit turn) racket drop or his uncoiling action in the image you posted. He (fully) extends his left arm shortly after this. He doesn't seem to keep it extended to the side (fence) quite as long as others I've studied. He does have it bent again late in his drop as he starts to uncoil. It remains bent as his uncoil speed increases

Don't follow what you are trying to say about the serve. The tossing arm is fully extended during the trophy phase. It starts to come down as the racket is dropped and starts to pick up a bit speed. As the racket is dropping, it is fairly close to the body. As this happens, the cartwheel (shoulder-over-shoulder) action and uncoiling of the torso commence.

The tossing arm is tucked into the body as the racket arm & racket extends upward to contact the ball.
I say, you start rotating with limbs as far away as reasonably possible. This stage may go relatively slow, it's start of uncoil, picking up momentum. Then you want to peak acceleration: it happens by forceful pushing off the ground, twisting the trunk/counter-swinging legs in some cases, also rotating around the front foot in neutral-stance groundstrokes... and tucking off-arm in - the process of tucking accelerates rotation, not the tucked position after the process is complete.

For serve - yes, true, peak body angular acceleration shall be timed with racquet drop (y) For FH it's when racquet is in slot position.

I'm arguing against the idea that hitting arm/racquet is close to the body for max acceleration. It's not. It's where it should be to ensure strong link and to produce desired swingpath. Neither of this pics has arm close to the body, in my opinion: they just have elbow and wrist in positions which ensure no weak link engaged (small muscles) too early.

Accelerating torso rotation on FH, drop mostly complete, off-arm started the tuck-in motion:
carlos-alcaraz-forehand-slow-motion-analysis-v0-PYSZfE_kH34X7ug731Z2gSqTQHzfTGmJO6d2Kk4SBj8.jpg


Racquet drop, accelerating shoulder-over-shoulder with off-arm tuck-in in process:
maxresdefault.jpg
 

Smecz

Semi-Pro
There is too much motion blur and the recording speed is too slow to tell where the ball was hit on the racket face at 13 seconds in the Monfils video
Lot of true,but I can see that it is not a sweet spot anywhere, but close to the tip, i.e. near the dead spot...

The best way would be to be able to see the shot in still frames, I don't have such a program.

Additionally, he ran away from the ball quite a lot, I watched it about 15 times before making the thread, I had to be sure that he was hitting the dead spot, because if I was wrong, this thread would make no sense...
 

Smecz

Semi-Pro
Federer has been using lower SW compared to Murray, Nadal and Djokovic. Monfils reported to have huge (386) SW as well.

The point is, oldschool pro racquet weights make the "deadspot theory" not applicable. But it makes upper hoop much more playable than what you have in no-tech traditional retail frames. If you can accelerate 360-380 SW stick.

I honestly admit that I added lead myself to 12, for power and to pull the racket forward.

But I didn't know that the sweet spot in the racket was changing and it was getting closer to the dead spot.

Logic tells us that the sweet spot would be best if it was in the middle, but if you counted in a real high-stakes match, how many times did a pro player hit the % in the middle of the racket?!

To be honest, when playing in a match, I don't focus on hitting the center of the racket, I focus more on hitting the ball with the string so as not to hit it with my frame.

Especially with slice, I try to hit instinctively feel the impact, if I hit the dead spot or sweet spot right, the ball is supposed to end up on the other side of the net...
 

Dragy

Legend
I honestly admit that I added lead myself to 12, for power and to pull the racket forward.

But I didn't know that the sweet spot in the racket was changing and it was getting closer to the dead spot.

Logic tells us that the sweet spot would be best if it was in the middle, but if you counted in a real high-stakes match, how many times did a pro player hit the % in the middle of the racket?!

To be honest, when playing in a match, I don't focus on hitting the center of the racket, I focus more on hitting the ball with the string so as not to hit it with my frame.

Especially with slice, I try to hit instinctively feel the impact, if I hit the dead spot or sweet spot right, the ball is supposed to end up on the other side of the net...
I wouldn’t use the wording “changing”, rather “expanding”. Because middle of stringbed benefits power-wise as well when adding weight at 12 o’clock.

In dynamic match environment you may mis-align yourself against the ball, and better have couple of inches margin for error. With standard 98-100 sqin frames I’d still aim for the middle on standard shots, because it’s where strings perform best. Better shape, better spin, better stability. But you can have upper hoop rather stable via stiffness, technology and/or extra mass. Just beware of making racquet too cumbersome to swing fast.
 

Smecz

Semi-Pro
wouldn’t use the wording “changing”, rather “expanding”. Because middle of stringbed benefits power-wise as well when adding weight at 12 o’clock.

In dynamic match environment you may mis-align yourself against the ball, and better have couple of inches margin for error. With standard 98-100 sqin frames I’d still aim for the middle on standard shots, because it’s where strings perform best. Better shape, better spin, better stability. But you can have upper hoop rather stable via stiffness, technology and/or extra mass. Just beware of making racquet too cumbersome to swing fast
I get it,that is, by adding a lead of equal weight to 12 and 6, I will expand the sweet spot up closer to the tip and down up closer to the heart...?!Yes?!

Still, when I play, I hit the center of the racket automatically, but when volley serves and other shots, I hit it confidently in different places on the string...

I have 3 versions of the lead at 12 o'clock:
little lead - feels a bit of power, nothing else
average lead - you can feel the difference, more power
a lot of lead - a lot of power, the racket is aggressive and pushes forward to attack the ball, but I played a few
times as an experiment, because it became difficult and it was not easy to hit swings, it was quite tiring (it is easy to get injured)

I usually play with a small amount of lead and sometimes with a medium amount of lead, since I realized what it was about, I had to have a lead of 12.

Now I'm curious about the fact that if I hit this racket with a lot of lead, I could have unconsciously hit the dead spot more often...?!
 

Dragy

Legend
I get it,that is, by adding a lead of equal weight to 12 and 6, I will expand the sweet spot up closer to the tip and down up closer to the heart...?!Yes?!
To six o’clock - no great effect on most frames. There’s generally enough mass effectively working from the lower part of the stick, it just needs “corresponding” mass at the tip to get activated. Kind of like see-saw, if it’s light, it’s easy to move even if the fulcrum zone is heavy. But once you add a stout person on the seat… ;)

If a frame has very flexy throat, which is also “empty” in terms of mass, so the frame is very polarized… this may make 6 o’clock zone anemic.

So no need to add mass to the bottom of the hoop usually, unless you want to change swinging properties (MgR/I for example). 3&9 and higher is all you need. 4&8 kind of lowest reasonable zone to start, if you want twistweight bump with limited SW increase.
 

Chas Tennis

G.O.A.T.
Lot of true,but I can see that it is not a sweet spot anywhere, but close to the tip, i.e. near the dead spot...

The best way would be to be able to see the shot in still frames, I don't have such a program.

Additionally, he ran away from the ball quite a lot, I watched it about 15 times before making the thread, I had to be sure that he was hitting the dead spot, because if I was wrong, this thread would make no sense...
Seeing the fastest part of tennis strokes - the ball & racket head.
It is easy to find videos that are clear. Don't interpret blurry videos, toss them, and find clear high speed videos with little motion blur.

100 MPH is 1760 inches per second.

1760"/ 240 frames per second = 7.3" movement between frame

240 fps shows a tennis stroke pretty well. But with the ball and racket both moving at speeds like 100 MPH, in different directions, I would never want to interpret a blurry ball and a blurry racket - that are separated by inches - and say I knew where on the racket face the ball had hit some time earlier. But if the ball and racket are touching or nearly touching when the frame was exposed, that's much better. More stuff to consider....... Most of the headaches melt away if you take advantage of what a cheap high speed video camera can do. There are other issues such as Jello Effect that need to be considered, especially when you are looking at a video taken with an unknown camera on the internet.

You can see the shot in still frames on Youtube. Stop Youtube, go full screen. Use the period & comma keys to move single frame on Youtube. To compare two Youtubes single frame - Post one above the other on this forum.

To compare two of your own videos - get Kinovea, a free, open source application that has a great many capabilities, such as a countdown timer.
 
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Smecz

Semi-Pro
To six o’clock - no great effect on most frames. There’s generally enough mass effectively working from the lower part of the stick, it just needs “corresponding” mass at the tip to get activated. Kind of like see-saw, if it’s light, it’s easy to move even if the fulcrum zone is heavy. But once you add a stout person on the seat… ;)

If a frame has very flexy throat, which is also “empty” in terms of mass, so the frame is very polarized… this may make 6 o’clock zone anemic.

So no need to add mass to the bottom of the hoop usually, unless you want to change swinging properties (MgR/I for example). 3&9 and higher is all you need. 4&8 kind of lowest reasonable zone to start, if you want twistweight bump with limited SW increase.
Thanks man for this info, I need to study this carefully, I like learning about such things.

I added lead on 3 and 9 for stability, but it helped in my game, I didn't feel comfortable...

I prefer 12 o'clock, my forehands were average strong, so I wanted to add more power to them, liked this aggressive pulling of the head forward..

Back to the dead spot,I watched Monfils' action again (he hits above the shoulder line) and there is a high ball with low speed, and in this case the dead spot usually involves hitting high balls such as smash and serve.

That is, dead spot high forehand, smash, serve, suits such shots, as long as they have relatively low speed.!! (this was mentioned earlier in the article when it is recommended to hit dead spot)

Even on this Haase return, the ball goes with the kick serve and slow, then you can probably hit a dead spot... Don't you agree?!...
 

Dragy

Legend
That is, dead spot high forehand, smash, serve, suits such shots, as long as they have relatively low speed.!! (this was mentioned earlier in the article when it is recommended to hit dead spot)

Even on this Haase return, the ball goes with the kick serve and slow, then you can probably hit a dead spot... Don't you agree?!...
Personally, I won't be intentionally trying to use any part of the stringbed that shrinks my margin for error. One exemption might be on serve, where I have full control with the toss. So middle of stringbed for me, or maybe higher when using racquets like Gravity, or Yonex shapes.

If I wanted to use the benefits of contact point farther away from my hand, I'd likely look onto 28 in. extended frames. And use middle of the stringbed with those.

Anyway, I don't think this whole idea of using record-braking slaps is relevant to tennis improvement. As a trick shot or fun shot - well, try, experiment, you could possibly get even more speed by using the edge of the frame instead of the strings.
 

Chas Tennis

G.O.A.T.
Lot of true,but I can see that it is not a sweet spot anywhere, but close to the tip, i.e. near the dead spot...

The best way would be to be able to see the shot in still frames, I don't have such a program.

Additionally, he ran away from the ball quite a lot, I watched it about 15 times before making the thread, I had to be sure that he was hitting the dead spot, because if I was wrong, this thread would make no sense...
SINGLE FRAME VIEWING OF YOUR VIDEOS

1) Windows Media Player to single frame a video on your computer. WMP is an older free Windows application that also works on Windows 11. I can't remember the keys to use it for single frame and prefer Kinovea. I have been using Kinovea for several years and like it very much.

2) Kinovea is better for single frame and can compare two videos that you record side-by-side on your computer. Kinovea is open source and free.

3) Youtube. If you want to compare Youtube videos on the forum itself - compare your video to a pro Youtube - you can first upload your video to Youtube. And then post the Youtube links one above the other in a forum reply. Youtube accounts are free. To single frame on Youtube, stop video, go full screen and use the period & comma keys.

4) Vimeo works the same way as Youtube. But hold down the SHIFT KEY and use the ARROW KEYS to single frame. Vimeo hosts videos as Youtube does. Last I heard first 5 GB are free.

If you do not want to post your videos on the public forum, you can use forum CONVERSATIONS and have a conservation with another poster that you know. You need 2 members because the forum does not allow a CONVERSATION with yourself. Click the envelope icon above in this reply box.

The best way to see what is true is to look at high speed videos, single frame. Everything in tennis depends on the techniques used for the strokes. There are pro strokes and then the lower level strokes are mostly DIY. There is great information for the pro stroke techniques. There is nothing for the DIY strokes.

SEARCHSINGLEFRAME
 
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JohnYandell

Hall of Fame
Here's the thing even if the so called dead spot had some advantage the chance of players hitting it consistently on groundstrokes is about zero. Our high speed studies showed players only found the center line of the string bed about 1 of 3 times with one third above and one third below.
 

SystemicAnomaly

Bionic Poster
Toly posted this. I miss Toly and his great posts, with composite pictures and videos.
To single frame on Youtube, stop video, go full screen and use the period & comma keys.

If the camera speed was actually 6,000 frames per second, then 6 frames would equal 1 millisecond. 4 milliseconds would be 24 clicks of the period and 5 milliseconds would be 30 clicks.

You can count frames and make a time line that shows ball deformation, string deformation, first touch to last touch VS time. Please post if you do.

-------------------------------------------------------------------------------------------------------------------------------------
Time in milliseconds and the time = 0 at first touch of ball or closest to impact is a good time scale for fast tennis motions.

Video application Kinovea, free open source, has a countdown time mode where the milliseconds shown on each frame indicate the time before first touch or impact.
Only took a quick look at this. It APPEARS the dwell time is closer to 3ms than I would have expected. Did you take a closer in-depth look at this?
 

Dragy

Legend
Look at Alcaraz hitting this passer on the full run (close-up at 0:40) - he doesn't go with the tip, he uses fat part of the stringbed:


There is no exact impact frame, but it's obvious:

LXFwtSn.png
 
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