Role of forearm muscles in forehand

[JonC]

So as not to proclaim false ideas or go on a journey of self discovery in my tennis I'd like opinions on what Dimitrov's forearm muscle tension is accomplishing. Reading through the USPTA site, I can't find anything on the use of the forearm which seems strange since the forearm of the hitting arm usually much larger than the nondominant arm.


"Note that the wrist is also bent, oftentimes at a 90-degree angle in what's commonly known as the "double bend." As discussed earlier, the first and second "L's" elongate the backswing, creating a tremendous amount of racquet speed at the point of contact. The "L"-shaped elbow, coupled with the bent wrist, provides a consistent angle on the racquet face, allowing the player to exert critical control over the high velocity of the racquet head and ball at the point of contact. Furthermore, having the ability to pivot on the bent elbow allows the natural rotation of the forearm, wrist and hand as the ball is struck (commonly known as the "windshield wiper"), imparting a tremendous amount of topspin to the ball. Virtually all world-class forehands use the windshield-wiper arm rotation action and the third "L" facilitates this biomechanical process."

- nothing there about using the forearm muscles - the forearm controls the wrist and the grip.

http://www.addvantageuspta.com/defa...tterID/1055.htm?AspxAutoDetectCookieSupport=1

 

[Memnoch]

The way his wrist is bent he has to use his wrist extensors to keep it in that position. He also needs the flexor digitorum muscles for holding the racket. Pronator muscles such as the Pronator Teres in the forearm will be needed for the follow through.

It is obvious that the dominant arm will be more developed considering you use many of the forearm muscles in tennis. The main power for groundstrokes isn't' coming from the forearms but they are part of the kinetic chain.

Also, the vibration from striking the ball may stimulate greater bone growth in the dominant arm.

 

[JonC]

The way his wrist is bent he has to use his wrist extensors to keep it in that position. He also needs the flexor digitorum muscles for holding the racket. Pronator muscles such as the Pronator Teres in the forearm will be needed for the follow through.

It is obvious that the dominant arm will be more developed considering you use many of the forearm muscles in tennis. The main power for groundstrokes isn't' coming from the forearms but they are part of the kinetic chain.

Also, the vibration from striking the ball may stimulate greater bone growth in the dominant arm.

So he's coming out of the linear part of the stroke and making a movement up and around with the racquet head. This change in direction requires an increase in both grip strength and wrist extension strength to counter the forces of that direction change. Would you agree with that?

 

[Memnoch]

So he's coming out of the linear part of the stroke and making a movement up and around with the racquet head. This change in direction requires an increase in both grip strength and wrist extension strength to counter the forces of that direction change. Would you agree with that?

I think the up and around movement probably uses the pronator muscles the most. I wouldn't be surprised if there were an increase in grip strength and wrist extension during the movement but I'm not sure how it compares to other parts of the stroke. Only way to find out is to run some EMG studies.

 

[Cheetah]

Pronation, holding wrist steady upon taking force of incoming ball, wrist manipulations on certain shots in volleys squash shots. Lots of things.
Loose grip on fh imo

 

[Gazelle]

You really shouldn't be thinking about your forearm muscles. Keep it a bit simplier.

 

[JonC]

Pronation, holding wrist steady upon taking force of incoming ball, wrist manipulations on certain shots in volleys squash shots. Lots of things.
Loose grip on fh imo

So it's correct to say that the forearm is very active around contact with pronation and wrist extension. The arm is not relaxed and the wrist is strong.

 

[JonC]

You really shouldn't be thinking about your forearm muscles. Keep it a bit simplier.

Why? It is imperative to know what the hand and arm should feel like at contact. I know this will vary depending on the shot. But on a decently struck ball to the forehand when you are returning at the same pace - what does it feel like? Loose, rigid, what? I can already hit the ball just fine but I'm missing something and hitting with a relaxed hand and arm is not the key. I've said before that a return of serve is not hit with with a loose feel so I'm thinking that I'm too loose on other forehands. I know for sure a 1hbh does not feel loose at contact.

And Dimitrovs forearm surely shows that he's doing a lot of work with it.

 

[Cheetah]

So it's correct to say that the forearm is very active around contact with pronation and wrist extension. The arm is not relaxed and the wrist is strong.

I think there are many ways to hit a fh so I hesitate to say 'correct'..

'Very active is a matter of interpretation. If you are trying to hit with excessive top spin (maybe a dipping passing shot, or certain shots where you have made a decision that requires extra TS like a looping deep penetrating ball to someone's bh to give you a chance to come in or whenever you want extra spin + then you can really work the forearm. Sometimes you realize your timing wasn't the best and you might have to make some adjustments mid swing or maybe for some reason you change your mind on how you want to shape the ball and you'll have to adjust the attack on the ball and you can use your forearm for that.

For a normal heavy rally ball, imo, you can get really good spin and have your forearm pronate in the same motion as when requiring max spin just by how you set up and the hitting structure of your arm and racquet and where you make contact relative to your swing path etc etc with having to manually manipulate the forearm. If everything is right, the setup and just the swing alone will move your arm / hand / forearm automatically in a very smooth natural relaxed motion. Like a smooth relaxed throw while playing catch w/ someone... everything pretty much moves on it's own if you know how to throw a ball.

Also, it's possible to get the same motions (pronation, door knob turn, buttcap snap as the video above terms it) with just very small tugs during the swing. If you have a good setup and swing going forward, a very small tug say with your wrist, or butt of the palm or index finger or any other muscle in your body, or even a slowing down of one muscle group or joint whatever during the swing can change the racquet movement to the desired effect.
So for example if you want to swing with a large windshield wiper effect for big TS you can either
1) swing the racquet and hold everything tight and really forefully use your wrist and forearm muscles to muscle that racquet in the ww shape or
2) swing low to high, apply a slight tug at the right moment in the swing, maybe slow down your torso rotation and out comes the exact same motion as in option 1 only faster, smoother and with less effort.
Both ways work.

So it's possible to create all needed motions without having a very manually active forearm. It could be a direction change or tug or velocity change in some part of the body and the arm will respond.

I don't think you need to use too much, if any, forearm muscles to keep the wrist in flexion. If you arm and wrist are relaxed the wrist and racquet will lay back on their own and stay that way during the swing. I think a little muscle is required or can be used or is used at impact to keep the wrist at that degree of bent (ie; prevent from laying back more upon collision etc).

So in short, imo, i think it's best to swing in a relaxed, fast manner and let the momentum and centripetal forces do their thing on their own.

 

[Cheetah]

This video is kind of related I think

 

[JonC]

Thanks for that response. There are balls that I can hit relaxed - the ones that come into my strike zone - hip to knee. But if they pop up above that I don't see how a you can swing relaxed through a ball like that, I have to actively use my wrist to get those ball back. Maybe my problem is positioning.

 

[cjs]

You really shouldn't be thinking about your forearm muscles. Keep it a bit simplier.

Tend to agree with this. At most think about the position of your racquet and if need be the position of your wrist.

 

[JonC]

This video is kind of related I think

Doesn't the push imply increased grip strength and a more solid wrist? I'm doing what he says - I start out lose, get the lag, and then make everything more solid at contact. That's opposed to how I was trying to hit a while back which was loose all the way through.

 

[JonC]

Anyway, I started hitting this way after I discovered that I could markedly improve my return of serve by tightening up my grip at contact. I then found that when playing these ex-college players and they're blasting the ball at me, I could stay in the rally by firming up the grip a bit. So I don't know what's going on but it's working.

 

[Cheetah]

Doesn't the push imply increased grip strength and a more solid wrist? I'm doing what he says - I start out lose, get the lag, and then make everything more solid at contact. That's opposed to how I was trying to hit a while back which was loose all the way through.

Yes I think you can interpret / apply it that way.

For debate's sake I also think one could also argue that you can still get the same push type of pushing racquet motion by using any number of muscles or timing to make the racquet move that way. I think that I could either "push" using a tight grip and solid wrist and 'make the racquet drive though the ball towards the target - or - accomplish the same push / drive motion by holding / tightening my upper arm or shoulder or degree or lack of degree of rotation at the right time right?

Probably it's a combination of both or maybe some ppl do it one way and other's do it differently. That's why everyone's stroke looks different.

Personally, I have never ever even once in my life consciously tried to tighten my grip for a ground stroke. I just swing. I can hit heavy ts or dipping passing shots or a very flat drive. no tightening for me. I've had the racquet fly out of my hands when my overgrip has worn numerous times and you see the pros do this too.

 

[JonC]

Yes I think you can interpret / apply it that way.

For debate's sake I also think one could also argue that you can still get the same push type of pushing racquet motion by using any number of muscles or timing to make the racquet move that way. I think that I could either "push" using a tight grip and solid wrist and 'make the racquet drive though the ball towards the target - or - accomplish the same push / drive motion by holding / tightening my upper arm or shoulder or degree or lack of degree of rotation at the right time right?

Probably it's a combination of both or maybe some ppl do it one way and other's do it differently. That's why everyone's stroke looks different.

Personally, I have never ever even once in my life consciously tried to tighten my grip for a ground stroke. I just swing. I can hit heavy ts or dipping passing shots or a very flat drive. no tightening for me. I've had the racquet fly out of my hands when my overgrip has worn numerous times and you see the pros do this too.

Not to take up your whole night but you have a loose grip on the return as well? It seems that when I tried to do that (not on a return but on a hard hit rally ball) it would sometimes work but too often I'd hit it flat and it would sail way long. You're probably right, if I can hit a strong shot with good spin off an easy ball why couldn't you do the same on a harder hit ball. I think it may be the topspin they're putting on it - maybe I'm just not able to just the ball well enough.

 

[Cheetah]

I should have clarified... i consciously tighten my grip for returns and volleys (unless it's a drop volley).

Also, maybe you should check if you have a good sound grip on the handle. Do you have your index finger extended like a trigger for support or are you full on 100% hammer? Is your index knuckle firmly planted on a bevel in such a way that your are using that knuckle for stability, power and feel of the ball? Is your thumb laying on the bottom of your fingers or the racquet handle for support or is it not utilized at all like many ppl do? Do you have the buttcap firmly planted in a good spot on your heel pad? If you have the heel pad extended past the buttcap you could try experimenting with holding the racquet slightly higher up on the handle. All of those things make a difference in how stable the racquet is in your hand on impact and how tight you have to hold the racquet.

 

[watungga]

Index finger extended like a trigger = will give you Dmitrov forearm, its huge. I've said this, coz when you grip the racquet harder and with wrist bent back on ball impact, it flexing tightness in a lot of parts in your forearm muscles.
Midway between hammer and trigger grip is best for a relaxed grip in all your motion of a FH stoke and then a little bit stronger grip on impact.

 

[Chas Tennis]

Research using high speed multi-camera motion capture systems have provided 3D measurements of body part locations and joint angular positions for tennis strokes. EMG Signal nerve signal research has also been done for the 'active' muscle shortening during tennis strokes. I interpret 'active' to mean only the Sarcomere's Actin & Myosin, 'cross bridge' muscle shortening. For the muscle's 'passive' shortening forces and nerve signals I don't believe that any research has been done on tennis strokes. See Hill Muscle Model for the meaning of 'active' and 'passive'.

In other words, there are probably no measurements of individual muscle forces during tennis strokes.

I don't believe that there is research or measurements to answer this question especially because how Titin works is not well understood yet. Titin is the elastic component, the rubber band, used in the stretch shortening cycle. How or if EMG Signals or similar nerve signals are used with Titin is the subject of current research.

For background information on this subject, search combinations of these terms: Sarcomere, Actin, Myosin, Titin, Animations,

Also, Hill Muscle Model.

You should find many very instructive Youtubes on the Sarcomere's operation showing how the Myosin reaches over to the Actin with 'cross bridges' and active muscular forces are created. This process has been reasonably well understood for decades. But you probably won't find much on Titin..........

'Google Scholar' finds research publications much more directly than a simple Google search. Researchgate often offers publications not otherwise available free.

Thread
Biomechanics References on Tennis Strokes
http://tt.tennis-warehouse.com/index.php?threads/biomechanics-references-on-tennis-strokes.427364/

FYI
EMG Signals - have clearly been associated with the Sarcomere's Actin and Myosin muscle shortening forces.

Titin is involved in the Sarcomere's elastic shortening forces. That is, the stretch shortening cycle involves Titin. I believe that it has not been established what signals, if any, trigger Titin to provide muscle shortening forces.

The forearm has superficial muscles, outermost muscles, that are associated with wrist motion. These are probably the muscles that show most in the Dimitrov forearm picture in the OP. Wrist extensor muscles start at 2:40.

 

[JonC]

Index finger extended like a trigger = will give you Dmitrov forearm, its huge. I've said this, coz when you grip the racquet harder and with wrist bent back on ball impact, it flexing tightness in a lot of parts in your forearm muscles.
Midway between hammer and trigger grip is best for a relaxed grip in all your motion of a FH stoke and then a little bit stronger grip on impact.

That's interesting - I do have a problem with my grip, I don't have a go to grip - sometimes the buttcap is in the heel of my hand, sometimes the heel is above buttcap. Sometimes I try to spread the fingers, sometimes not - when I'm thinking about it. It's definitely not a go-to grip. I also sometimes find myself in an eastern grip for some reson. That could be a lot of my problem.

 

[JonC]

Thanks Chas - so maybe Dimitrov is returning serve here, holding his wrist extended and steady.

 

[Cheetah]

You don't have a go to grip? Wow.
You need to settle on a grip. Even a very small change in grip has a sizable difference in the swing mechanics. If you are not using the same grip for every shot then ... idk.. it's almost like you are not playing tennis. How can your train your muscle memory and work out the coordination and nuances for every shot if you keep changing grips? To me that's wasting time... If it takes the often heard 5000 repeated correct strokes to learn a shot then it would take you 15000 minimum or whatever . you get the point.
Get a grip. Seriously.. that's a pretty major issue imo if you are trying to improve.

 

[JonC]

You don't have a go to grip? Wow.
You need to settle on a grip. Even a very small change in grip has a sizable difference in the swing mechanics. If you are not using the same grip for every shot then ... idk.. it's almost like you are not playing tennis. How can your train your muscle memory and work out the coordination and nuances for every shot if you keep changing grips? To me that's wasting time... If it takes the often heard 5000 repeated correct strokes to learn a shot then it would take you 15000 minimum or whatever . you get the point.
Get a grip. Seriously.. that's a pretty major issue imo if you are trying to improve.

My comment was a bit of hyperbole, sorry. I'm a bit of a perfectionist, when I say I don't have a go to grip I mean that I find myself not having the correct grip way too often. And, its true, I experiment with different grips and that's probably a bad idea. I need to focus more on my grip - and, ironically, tightening up a bit helps with that focus.

 

[JonC]

My comment was a bit of hyperbole, sorry. I'm a bit of a perfectionist, when I say I don't have a go to grip I mean that I find myself not having the correct grip way too often. And, its true, I experiment with different grips and that's probably a bad idea. I need to focus more on my grip - and, ironically, tightening up a bit helps with that focus.

Also, I switched to a bit more western (to full semi-western) not too long ago - so that's an issue too. I know it sounds like I'm a beginner - not the case.

 

[Cheetah]

Understood.
Good luck.

 

[Enga]

In my opinion, a bigger forearm is a sign of someone with serious control. And I feel it comes more from 1hbh backhand usage than fh.

I think this because you dont really need big muscle to hit hard, but that big muscle in the forearm can allow for extrme stability and control.

 

[JonC]

In my opinion, a bigger forearm is a sign of someone with serious control. And I feel it comes more from 1hbh backhand usage than fh.

I think this because you dont really need big muscle to hit hard, but that big muscle in the forearm can allow for extrme stability and control.

That's a good thought - probably is more 1hbh than fh.