Serve shoulder turn / upper body

[FiReFTW]

So we had this group lesson we have 2 times a week and we are serving more now in this group lesson.
And the coach is insistant that I change my upper body turn and rotate more, so I have like my back facing the opponent ala Sampras.
My serve was getting decent feeling lately after I had a break from tennis and now with this its messed up again.
The issue obviously is that im just not used to it because its completely different feeling than my usual movement.

Now I do see some pros in that I seem to get more spin with this type of turn but I feel like its harder to hit through the ball and a stronger flatter serve.

My question is, is this turn worth investing time and effort into? Or a waste of time?

I can make videos to show how it looks either way.

 

[Keendog]

waste of time, coach is an idiot. Any change like that is going to screw up your timing and serve will get worse. The coach needs to explain the long term benefits you are going to get that will be worth it eventually for the short term pain. They obviously haven't cos now you're in here asking internet strangers about it.

This is typical, people announce they are a "profeesional", swan around all arrogant like they know everything, and if they suggest something it makes you think they are an authority on it and doubt yourself. You said it yourself mate, the serve feels worse so you know deep down. Glad it worked for sampras but what has that got to do with anything?

 

[FiReFTW]

Yes but hes stubborn and its a group session, if I say anything he acts like I know it all and then ignores me and acts rude in the sessions.

 

[FiddlerDog]

Focus on the biggest weaknesses in your game.
Have you been playing real matches or polishing practice strokes?

 

[SystemicAnomaly]

It could be worse. He could ask you to start with an extreme coil a la John McEnroe

Yes but hes stubborn and its a group session, if I say anything he acts like I know it all and then ignores me and acts rude in the sessions.

If the coach is as bad as you say, he sounds like a jerk or a pompous you-know-what.

I will often ask students to employ a bit more coil. This is often facilitated by lifting the tossing arm at a smaller angle wrt the BL. Usually somewhere between 0° and 45° -- often 30° or less to get a bit more coil. But I would not ask somebody to go too far past their comfort level to develop this.

 

[nvr2old]

Find another group lesson and instructor.

 

[FiReFTW]

Focus on the biggest weaknesses in your game.
Have you been playing real matches or polishing practice strokes?

I haven't played for a bit but now I went to hit a bit to get back into the rhytm and then I played like 7 or 8 matches, and now started with some group sessions (the ones I said this is from)

 

[Dragy]

I have to points to suggest:
- I agree with those above it’s not something uniform. Your coil was healthy in those videos you posted before.
- Meanwhile I find it useful to sometimes toy with moderate changes. Just make some serves with more coil and see how it feels. Don’t commit to it fully, but experiment and see if your “no-thought” execution becomes better after all.

 

[ballmachineguy]

This just in: there is no such thing as “coiling” on a serve. If you are, you are doing it wrong. Very misleading term.
Maybe that corkscrew motion has some. Probably why it is so popular.

 

[SystemicAnomaly]

This just in: there is no such thing as “coiling” on a serve. If you are, you are doing it wrong. Very misleading term.
Maybe that corkscrew motion has some. Probably why it is so popular.

What are you blathering about here?

 

[jga111]

Invest more time. Just need to tweak timing of your release. Then you can make a call - give it a chance

 

[5263]

So we had this group lesson we have 2 times a week and we are serving more now in this group lesson.
And the coach is insistant that I change my upper body turn and rotate more, so I have like my back facing the opponent ala Sampras.
My serve was getting decent feeling lately after I had a break from tennis and now with this its messed up again.
The issue obviously is that im just not used to it because its completely different feeling than my usual movement.

Now I do see some pros in that I seem to get more spin with this type of turn but I feel like its harder to hit through the ball and a stronger flatter serve.

My question is, is this turn worth investing time and effort into? Or a waste of time?

I can make videos to show how it looks either way.

the big key here is knowing the main purpose of the coil. Do you understand what it sets up? (and the answer isn't to just uncoil like you coiled as a baseball pitcher might)

 

[Raul_SJ]

You need to coil. If you do not coil you are leaving power on the table. Why do you think the GOAT servers Sampras, Fed, Mac have back to the opponent? It does not have to be extreme like Sampras and Mac but it is a must!

#KineticChain

 

[FiReFTW]

I will make a video today and post it here so you can see both serves.

 

[FiReFTW]

Here are the vids, btw I know I have alot of flaws in my serve (for example I should keep my left arm upwards more and longer etc) but please just focus on the issue of the coil and upper body turn and arm.

The difference is quite obvious in the videos so you will see the motion is very different.

Currently after trying it today a bit more I have to say that perhaps it might have merits... I just need time to get used to it, I actually can get quite alot more spin I feel, and with the toss placement and a bit of different motions I can hit a more powerful serve too not just a very spinny one.

But idk, what do you guys think, is it worth going for it and risking my old serve that im used to, could the potential be here?

 

[SystemicAnomaly]

The difference is quite obvious in the videos so you will see the motion is very different.

Is there really a huge difference? I only took a quick look so I didn't really pick up on those "obvious" diffs. Will have to look again at them later with a more discerning eye -- when I am much less fatigued.

What do you think the obvi diffs are?

 

[Wurm]

But idk, what do you guys think, is it worth going for it and risking my old serve that im used to, could the potential be here?

Personally I'd say absolutely not and I worry about anyone coach who references the extreme shoulder turn of Sampras as something normal people should aim for.

In your old video I see nothing wrong with what your upper body is doing. Where I see room for improvement is in your lower half.

 

[FiReFTW]

Is there really a huge difference? I only took a quick look so I didn't really pick up on those "obvious" diffs. Will have to look again at them later with a more discerning eye -- when I am much less fatigued.

What do you think the obvi diffs are?

Slightly more shoulder turn and my arm is going more behind me as I start going into the trophy, beforehand is more sideways raising up

 

[FiReFTW]

Personally I'd say absolutely not and I worry about anyone coach who references the extreme shoulder turn of Sampras as something normal people should aim for.

In your old video I see nothing wrong with what your upper body is doing. Where I see room for improvement is in your lower half.

Its a hard decision because I feel like with the new motion I do get more spin.

 

[FiReFTW]

Is there really a huge difference?

I made pic comparison so you can see, upper is old, bottom is new

 

[Dragy]

Its a hard decision because I feel like with the new motion I do get more spin.

That’s possible as you swing more across. I suggest that you stay with it for some time, just don’t make it the main and only focus. After some time just settle where you will.

 

[eah123]

I think there is merit to trying more shoulder turn if your goal is to increase the power or consistency (through increased top spin) of your serve. Also, this will allow you to use your chest muscles more and be less reliant on arm and shoulder muscles for power. In the long run, it may also prevent shoulder injury. Here is a good video from Jeff Salz about this topic:

 

[SystemicAnomaly]

I made pic comparison so you can see, upper is old, bottom is new

I do like the elbow position (2nd image) in the 2nd sequence. It looks like you get a good stretch in the shoulder and (right) pec muscle. I didn't not check the video to see if you get that much in your older serve.

Not sure if you really need as much coil as you are going for in the newer serve sequence. Perhaps something in between the old and the new coil might be better. It does seem like an effort for you to get back around (the uncoil). Almost forced (or a bit of a struggle). For some reason it just doesn't look quite as natural as it could be. Maybe it's not as fluid, not flowing quite the way it should be.

In both the Old and New serves I would have liked to see more drive upward. Leg drive upward and driving the chest upward. Seems like you might be spending a little spend too energy trying to come around and jumping into the court rather than driving upward somewhat more.

I thought you were tossing arm looked okay in the videos but in looking at these image sequences, it appears not. Either it's not getting as close to vertical as it could or it's just coming down a bit too early.

 

[FiReFTW]

I do like the elbow position (2nd image) in the 2nd sequence. It looks like you get a good stretch in the shoulder and (right) pec muscle. I didn't not check the video to see if you get that much in your older serve.

Not sure if you really need as much coil as you are going for in the newer serve sequence. Perhaps something in between the old and the new coil might be better. It does seem like an effort for you to get back around (the uncoil). Almost forced (or a bit of a struggle). For some reason it just doesn't look quite as natural as it could be. Maybe it's not as fluid, not flowing quite the way it should.

In both the Old and New serves I would have liked to see more drive upward. Leg drive upward and driving the chest upward. Seems like you might be spending a little spend too energy trying to come around and jumping into the court rather than driving upward somewhat more.

I thought you were tossing arm looked okay in the videos but in looking at these image sequences, it appears not. Either it's not getting as close to vertical as it could or it's just coming down a bit too early.

Yeah you are right, with the new serve I get alot more spin the ball kicks a ton its insane, but you are right when you say it feels slightly forced and not as fluid, perhaps I should try something in between and see how that goes.

 

[ballmachineguy]

What are you blathering about here?

Feet, hips and shoulders all in the same line for the pros. What is coiled? Nothing.
Calling it coiled will mislead people into doing something they shouldn’t. You should know better.
Having your back to the receiver is not being coiled. Even J Mc had his feet parallel to the baseline when his back was to the server. And you don’t need to be a Richard, especially when incorrect.

 

[SystemicAnomaly]

Feet, hips and shoulders all in the same line for the pros. What is coiled? Nothing.
Calling it coiled will mislead people into doing something they shouldn’t. You should know better.
Having your back to the receiver is not being coiled. Even J Mc had his feet parallel to the baseline when his back was to the server. And you don’t need to be a Richard, especially when incorrect.

I do know better and I still refer to it as coiling, as do many other coaches -- some prominent & very high level coaches (who usually have access to biomechanics experts).

Semantics? You appear to have a rather limited definition of coiling. Many would consider the very act of turning away from the net, turning "side on" or further as coiling -- a rotation employed, in part, to increase stored energy in the system. From this rotated position, there is an "uncoiling" rotation employed, as part of the kinetic chain, to turn this stored energy into kinetic energy.

Why do American football QBs and baseball pitchers turn away from their target area for their preparation? Many will refer to this turning as part of coiling.

However there is more to all this than that. Quite often, the feet and hips are not initially set up in the same direction as the upper torso. This provides added potential energy stored in the core and elsewhere.

 

[SystemicAnomaly]

Feet, hips and shoulders all in the same line for the pros. What is coiled? Nothing.
Calling it coiled will mislead people into doing something they shouldn’t. You should know better.
Having your back to the receiver is not being coiled. Even J Mc had his feet parallel to the baseline when his back was to the server. And you don’t need to be a Richard, especially when incorrect.

Not only have have these players turned away from the net, we often see that parts of the lower body, the hips and the upper torso are oriented in different directions. For the serve, the front foot and knee often appears to be oriented in a different direction than the hips. Furthermore, there's often an additional twisting of the upper torso, relative to the hips, that increases tension (stored energy) in the core. We see diffs in other strokes as well -- most noticeably, the open stance Fh and many 1h Bh.

 

[ballmachineguy]

Not only have have these players turned away from the net, we often see that parts of the lower body, the hips and the upper torso are oriented in different directions. For the serve, the front foot and knee often appears to be oriented in a different direction than the hips. Furthermore, there's often an additional twisting of the upper torso, relative to the hips, that increases tension (stored energy) in the core. We see diffs in other strokes as well -- most noticeably, the open stance Fh and many 1h Bh.

Thanks for the pics, they prove my point. The servers have their feet, hips and shoulders all aligned. The forehand guy is “coiled.” I do have a limited definition of coiled. You have to be coiled. There are many words in English to use when you are not. I’m sure you can find one.
Pitchers and QBs do coil. There shoulders are turned more from the target than hips. Feel free to use that term for pitching and passing. Better to find a different term for tennis serve where you are definitely not coiled. And, I don’t care who else uses that term in tennis, they are incorrect too!

 

[Dragy]

 

[SystemicAnomaly]

Thanks for the pics, they prove my point. The servers have their feet, hips and shoulders all aligned...

How long have you been legally blind?

Roger's R foot & knee are angled toward the BL. Nearly 45° in the image posted. (Pete is closer to parallel in this respect but incorporates more of an Archer's bow instead). Roger's hips are angled away from the BL, perhaps about 30°. His upper torso / chest is closer to 45° away from the BL.

This last diff is known as separation angle.

 

[ChaelAZ]

I'd work on whatever produces this kind of wide kick serve at :12 in.

 

[SystemicAnomaly]

.And, I don’t care who else uses that term in tennis, they are incorrect too!

So everyone else is out of step except for you? Hmmm. Coil is a common terminology that coaches use for the serve for getting their point across about rotating away from the net and BL. Rotation, turn, torque, coil are all variations on the same theme. This is the language of coaches of the past as well as the present.

Many coaches will also speak of a separation angle on the serve. Separation angle refers to a difference in the orientation of the hips relative to the upper torso / chest.

Vic Braden, a pioneer in the tennis analysis / mechanics, frequently spoke of coil on the serve. Especially, with his J-toss motion where the upper torso did rotate more than the hips.

Kevin Garlington speaks, in depth, of separation angle & coil on the serve (after 8:30):

The Serve Doctor, Pat D of IMG, talks about rotation and coil in his cylinder drill. In the following spring-loaded serve, Pat promotes a very substantial separation angle for the serve. This greater offset of the hips from the chest orientation provides a very easy power source.

Simon of Top Tennis Training:

Jeff Salzenstein:

Generate Easy Power On The Serve - Harnessing The Coil and Racquet Drop | SportsEdTV

GENERATE EASY POWER ON THE SERVE - HARNESSING THE COIL AND RACQUET DROP. Former top 100 ATP pro Jeff Salzenstein will show you how to generate easy power on the serve by maximizing your coil and ensuring a relaxed racquet drop. In this video, Salzenstein explains how your base affects your...

sportsedtv.com

 

[weelie]

I made pic comparison so you can see, upper is old, bottom is new

I think Salzenstein advocates turning the back foot a bit towards the back fence, to allow a more natural coil. Did you try that?

 

[ballmachineguy]

Thanks again for those as well.

Not directed at you, Dragy,
Feet, hips, shoulders all doing the same thing. A 5 degree difference at best. If you stand up and start turning your shoulders without turning your hips, you have to have a significant difference come about before you feel any muscle stretch that would be considered coiling. And, even if you felt said stretch it would be damaging to your serve. It’s not a coil, it is simply facing in a direction other than directly toward your opponent/target. Saying “coiling” will lead people to believe they are supposed to be twisting to the point of feeling a stretch on core muscles. Similarly, if people try to increase power by turning their hips first to pull their shoulders around on the drive to hit the serve it will cause problems. You stand in the direction you do for the serve to be able to hit the ball down into the serve box. Others using a misleading term doesn’t make it right either.

 

[nochuola]

Thanks again for those as well.

Not directed at you, Dragy,
Feet, hips, shoulders all doing the same thing. A 5 degree difference at best. If you stand up and start turning your shoulders without turning your hips, you have to have a significant difference come about before you feel any muscle stretch that would be considered coiling. And, even if you felt said stretch it would be damaging to your serve. It’s not a coil, it is simply facing in a direction other than directly toward your opponent/target. Saying “coiling” will lead people to believe they are supposed to be twisting to the point of feeling a stretch on core muscles. Similarly, if people try to increase power by turning their hips first to pull their shoulders around on the drive to hit the serve it will cause problems. You stand in the direction you do for the serve to be able to hit the ball down into the serve box. Others using a misleading term doesn’t make it right either.

I'm honestly just curious now as to where you think the hips and shoulders are for you to think they are relatively aligned. To help facilitate the conversation, do you mind drawing lines on the top-down images to show how exactly you think the shoulder and hips are aligned?

 

[nyta2]

@ballmachineguy @SystemicAnomaly interesting debate about "coil"
(by coil i imaging a torsion spring (my core/hip area) getting twisted tighter to store up energy that is released when we let it go)
maybe the argument is really about when the coil happens? or whether i can feel the coil? or maybe the difference in serve styles? (ie. maybe pinpoint stance relies more on a precoil, and the platform relies more on a late coil?)

open stance fh to me is like "precoiling"
but a pitcher throw, the "coil" happens "late" (ie. during the stride)

to me, the serve is powered by (1) legs, (2) core (torsion spring), (3) hip (pole vault analogy from @Serve Doc) (4) arm...
but the serve style can dictate how much energy is being derived from each of the power sources
eg. a beginner frying pan serve, chest to net, will be all arm
eg. a "squatty" serve might be all legs
neither having much coil and likely a bad serve motion (and similarly i tried to power my serve with all "coil" eg. hips facing net, and turn upper body backwards as much as i can, i will similarly have a bad serve motion)
but IMO most serves are somewhere in the middle,... having various degrees of contributions from all the power sources.

when i try to emulate mcenroes serve, i don't feel a "coil" through the core, so i presume the power has to come more from the legs, and hip load (pole vaulter)... or maybe like a baseball pitcher a "coil" is happening on the way up to contact (not sure as i don't do a good mcenroe serve impression)... but i presume there's some coil going on, but i'm not sensitive enough to feel it (or likely i'm not executing in properly)
but when i use a pinpoint (my normal serve motion), i do feel an immediate/pronounced coil (along with stronger hip load due to the coil (like twisting a torsion spring, then trying to bend it in half))

Maybe that corkscrew motion has some. Probably why it is so popular.

by corkscrew, did you mean pinpoint serve style?

Thanks again for those as well.

Not directed at you, Dragy,
Feet, hips, shoulders all doing the same thing. A 5 degree difference at best. If you stand up and start turning your shoulders without turning your hips, you have to have a significant difference come about before you feel any muscle stretch that would be considered coiling. And, even if you felt said stretch it would be damaging to your serve. It’s not a coil, it is simply facing in a direction other than directly toward your opponent/target. Saying “coiling” will lead people to believe they are supposed to be twisting to the point of feeling a stretch on core muscles. Similarly, if people try to increase power by turning their hips first to pull their shoulders around on the drive to hit the serve it will cause problems. You stand in the direction you do for the serve to be able to hit the ball down into the serve box. Others using a misleading term doesn’t make it right either.

in your model of the serve, what are the power sources contributing to the serve (rhs)
side note, in a torsion *bar*, a 5degree difference would be huge.

 

[SystemicAnomaly]

@Dragy @nyta2

Thanks again for those as well.

Not directed at you, Dragy,
Feet, hips, shoulders all doing the same thing. A 5 degree difference at best. If you stand up and start turning your shoulders without turning your hips, you have to have a significant difference come about before you feel any muscle stretch that would be considered coiling. And, even if you felt said stretch it would be damaging to your serve. It’s not a coil, it is simply facing in a direction other than directly toward your opponent/target. Saying “coiling” will lead people to believe they are supposed to be twisting to the point of feeling a stretch on core muscles. Similarly, if people try to increase power by turning their hips first to pull their shoulders around on the drive to hit the serve it will cause problems. You stand in the direction you do for the serve to be able to hit the ball down into the serve box. Others using a misleading term doesn’t make it right either.

5 degrees? Need a stronger optical prescription?


On one of those images, Roger's left foot and knee are nearly perpendicular to the direction of his upper torso / chest. Not aligned.

The hip-chest offset or separation angle I'm seeing is closer to 15°. Perhaps more. Note also that many servers will start to "uncoil" the hips prior to the upper torso. This will increase the max separation angle between the hips & the shoulders.

It's not just high-level coaches that are talking about separation angle or coil, it's coming from papers / studies from biomechanics experts, like a Bruce Elliott, Natalie L Myers (PhD), Ben Kibler, Gabe Jaramillo & others.

I've seen at least two different papers from Bruce Elliott that discusses separation angle on the serve. One of these is The Player Pevelopment Pathway: A Biomechanical Perspective. In the section, "The Learning Pathway in the Tennis Serve", he actually talks about a horizontal separation as well as a vertical separation angle.

Here's another reference to a Bruce Elliott study:

Figure 2-Peak shoulder tilt, separation angle and trunk rotations in...

Download scientific diagram | Peak shoulder tilt, separation angle and trunk rotations in the serve from publication: The Effect of Age on Discrete Kinematics of the Elite Female Tennis Serve | The importance of the flat serve in tennis is well documented, with an abundance of research...

www.researchgate.net

From N.L. Meyers & Ben Kibler:

A Biomechanically Based Observational Tennis Serve Analysis Method is Reliable and Valid - ProQuest

Explore millions of resources from scholarly journals, books, newspapers, videos and more, on the ProQuest Platform.

www.proquest.com

A Biomechanically Based Observational Tennis Serve Analysis Method Can be Used to Assess Serve Mechanics | Semantic Scholar

OF DISSERTATION A BIOMECHANICALLY BASED OBSERVATIONAL TENNIS SERVE ANALYSIS METHOD CAN BE USED TO ASSESS SERVE MECHANICS Traditional sports science motion analysis techniques using three-dimensional (3D) kinematics have demonstrated that proper mechanics enhance serve performance and improper...

www.semanticscholar.org

 

[nyta2]

@Dragy @nyta2

5 degrees? Need a stronger optical prescription?


On one of those images, Roger's left foot and knee are nearly perpendicular to the direction of his upper torso / chest. Not aligned.

The hip-chest offset or separation angle I'm seeing is at least 15°. Perhaps more. Note also that many servers will start to uncoil the hips prior to the upper torso. This will increase the separation angle between the hips and the shoulders.

It's not just high-level coaches that are talking about separation angle or coil, it's coming from papers / studies from biomechanics experts, like a Bruce Elliott, Natalie L Myers (PhD), Ben Kibler, Gabe Jaramillo & others.

I've seen at least two different papers from Bruce Elliott that discusses separation angle on the serve. One of these is The Player Pevelopment Pathway: A Biomechanical Perspective. In the section, "The Learning Pathway in the Tennis Serve", he actually talks about a horizontal separation as well as a vertical separation angle.

Here's another reference to a Bruce Elliott study:

Figure 2-Peak shoulder tilt, separation angle and trunk rotations in...

Download scientific diagram | Peak shoulder tilt, separation angle and trunk rotations in the serve from publication: The Effect of Age on Discrete Kinematics of the Elite Female Tennis Serve | The importance of the flat serve in tennis is well documented, with an abundance of research...

www.researchgate.net

From N.L. Meyers & Ben Kibler:

A Biomechanically Based Observational Tennis Serve Analysis Method is Reliable and Valid - ProQuest

Explore millions of resources from scholarly journals, books, newspapers, videos and more, on the ProQuest Platform.

www.proquest.com

A Biomechanically Based Observational Tennis Serve Analysis Method Can be Used to Assess Serve Mechanics | Semantic Scholar

OF DISSERTATION A BIOMECHANICALLY BASED OBSERVATIONAL TENNIS SERVE ANALYSIS METHOD CAN BE USED TO ASSESS SERVE MECHANICS Traditional sports science motion analysis techniques using three-dimensional (3D) kinematics have demonstrated that proper mechanics enhance serve performance and improper...

www.semanticscholar.org

hehe, just realized that when i do platform (i don't practice this) i do more of a squatty serve... but when i try to exaggerate the jut (load) of my front hip out in the direction my toes, then turn my shoulder/core slightly, i can definitely feel the coil, even if my shoulder alignment/angle does not appear to change much...

anywho i've been in the coil camp for forever (i can feel it happening in every full body throwing activity (ie. not darts)), but i do recall being confused by platform stance serves (copying mcenroe serve), and couldn't find when/where the coil happens (which made it harder to "get around")... easier (for me) to coil on the pinpoint stance (IMO)

 

[a12345]

The arms shoulders legs should be in line with each other rather than the top half of the body coiled round.

So the take back should be a tilt rather than a turn.

Thats because the first move is the legs drive the body upwards like your going up vertically in a cylinder. If you coil youll end up hitting around the ball and getting spin on it.

Unless thats your objective.

 

[SystemicAnomaly]

The arms shoulders legs should be in line with each other rather than the top half of the body coiled round.

So the take back should be a tilt rather than a turn.

Thats because the first move is the legs drive the body upwards like your going up vertically in a cylinder. If you coil youll end up hitting around the ball and getting spin on it.

Unless thats your objective.

Not quite sure what you're trying to say here. But it is not necessarily an either/or prospect. With high level serves, you will often see both a tilt and a robust coil. Coil can be a simple twist (unit turn rotation) or it can more of a multi-segment rotation (that produces an offset or separation angle between the hips and chest). Roger Federer's serve is a great example of this.

Here is a good example of generous coil vs minimal coil at the trophy position. In the L image, we see that the chest is oriented nearly directly backward (toward the camera) whereas the hips are angled more to the R. Easily, more than 20° of offset in the horizontal direction

The following graphic is from one of Bruce Elliott's biomechanical studies of the tennis serve. With his image image of separation angle, we see that the knees, hips & chest (shoulders) are not facing in the same direction. Separation initially often happens during the trophy as shown in the image above. Peak separation occurs when the lower body starts to uncoil a little bit before the upper body does

 

[ballmachineguy]

Not quite sure what you're trying to say here. But it is not necessarily an either/or prospect. With high level serves, you will often see both a tilt and a robust coil. Coil can be a simple twist (unit turn rotation) or it can more of a multi-segment rotation (that produces an offset or separation angle between the hips and chest). Roger Federer's serve is a great example of this.

Here is a good example of generous coil vs minimal coil at the trophy position. In the L image, we see that the chest is oriented nearly directly backward (toward the camera) whereas the hips are angled more to the R. Easily, more than 20° of offset in the horizontal direction

The following graphic is from one of Bruce Elliott's biomechanical studies of the tennis serve. With his image image of separation angle, we see that the knees, hips & chest (shoulders) are not facing in the same direction. Separation initially often happens during the trophy as shown in the image above. Peak separation occurs when the lower body starts to uncoil a little bit before the upper body does

You can’t twist and shoulder over shoulder at the same time. The two forces are in different directions. Your body opens toward the target just due to your right shoulder/arm driving through its swing path. If you actively try and twist into your serve it will be a mess.
I’m assuming you suggest this “coil” adds to the serve somehow and isn’t just about “lining up.” If that is the case, quit showing pictures of people at trophy. The actual hitting of the serve is from drop to contact. Any turning before drop is wasted/leak. If you are going to contend that the coil assists hitting the serve, show pics of drop and see how much coiling there is.
PS: I still don’t see any “coil” at trophy. Heck, I’m still not sure we are talking about the same thing.

 

[SystemicAnomaly]

You can’t twist and shoulder over shoulder at the same time. The two forces are in different directions. Your body opens toward the target just due to your right shoulder/arm driving through its swing path. If you actively try and twist into your serve it will be a mess.
I’m assuming you suggest this “coil” adds to the serve somehow and isn’t just about “lining up.” If that is the case, quit showing pictures of people at trophy. The actual hitting of the serve is from drop to contact. Any turning before drop is wasted/leak. If you are going to contend that the coil assists hitting the serve, show pics of drop and see how much coiling there is.
PS: I still don’t see any “coil” at trophy. Heck, I’m still not sure we are talking about the same thing.

I show static images of of players during the trophy phase and other phases of various strokes because it provides a simple, relatively easy-to-see illustration of certain aspects that many people cannot see in a more dynamic video (or in a confusing 3D rendering). I am hardly the only one to do this. If you peruse kinematic studies of tennis and other sports you will see this used quite a bit.

(I could not help but notice that you thanked @Dragy for his static images but criticized me for doing so)

Clarification. Terms like twist, coil, etc are often used in a very broad, general sense to refer to rotations of the joints, appendages, torso, etc. Coil is often used for something like a simple unit turn. OTOH, biomechanics researchers such as Bruce Elliott, Brendan Lay, Machar Reid and others use some of these terms in very specific manners.

I have seen several research papers by Bruce Elliott (and others) where separation angle is used in discussion of serve mechanics. From what I recall, he actually uses separation angle more than he uses the term coil in his studies. As I recall, your usage of the term coil also includes the concept of separation angle.

The drawn images I posted in #40 are from one of Elliott's many research papers on tennis mechanics. I posted it in reference to separation angle (and peak separation angle). His usage of Twist refers to a part of his study that I was not referencing. If you really want to see why it is there, you should get your hands on his research paper.

This image came from a study entitled, The Effect of Age on Discrete Kinematics of the Elite Female Tennis Serve. This study is a collaboration between researchers at Tennis Australia and the Univ of West Australia. It was conducted by B Elliot along with Brandon Lay and Machar Reid

I no longer have full access to this study, at this time, but you should be able to access it for yourself thru ResearchGate, Google Scholar, PubMed or some other source.

As I recall, this particular study compared the kinematics of various groups of female tennis players. The youngest group was developing preteen players. As I recall the second group was high-level teen players and the 3rd group was higher-level adult players.

IIRC, the term, twist, was used in this study in reference to a simpler implementation of the serve seen primarily in the youngest groups... before they developed more sophisticated mechanics. If interested, I would urge you to check this out for yourself. I will try to provide a couple of links in my next post.

 

[SystemicAnomaly]

@ballmachineguy

(PDF) The Effect of Age on Discrete Kinematics of the Elite Female Tennis Serve

PDF | The importance of the flat serve in tennis is well documented, with an abundance of research evaluating the service technique of adult male... | Find, read and cite all the research you need on ResearchGate

www.researchgate.net

The effect of age on discrete kinematics of the elite female tennis serve - PubMed

The importance of the flat serve in tennis is well documented, with an abundance of research evaluating the service technique of adult male players. Comparatively, the female and junior serves have received far less attention. Therefore, the aims of this study were to quantify the flat serve...

pubmed.ncbi.nlm.nih.gov

NOTE:

I agree that static images of different parts of the kinetic chain sequence do not tell the whole story. But they are useful for illustrating certain points and they also help us to see what is in the videos. Especially if one has access to high-speed videos.

 

[a12345]

Not quite sure what you're trying to say here. But it is not necessarily an either/or prospect. With high level serves, you will often see both a tilt and a robust coil. Coil can be a simple twist (unit turn rotation) or it can more of a multi-segment rotation (that produces an offset or separation angle between the hips and chest). Roger Federer's serve is a great example of this.

Here is a good example of generous coil vs minimal coil at the trophy position. In the L image, we see that the chest is oriented nearly directly backward (toward the camera) whereas the hips are angled more to the R. Easily, more than 20° of offset in the horizontal direction

​

With these 2 pictures it looks more like the left picture is all in line with each other and in the right picture the top half of the body has turned to the left and is out of whack with the bottom half of the body.

 

[SystemicAnomaly]

With these 2 pictures it looks more like the left picture is all in line with each other and in the right picture the top half of the body has turned to the left and is out of whack with the bottom half of the body.

Wow, can we possibly be looking at the same images? I've developed a pretty decent eye over the several decades I've been coaching tennis. But I don't believe really it takes an outstanding or a well-trained eye to see that, for the player on the R, both the hips & chest are oriented in nearly the same direction -- pretty much directly toward the side fence (parallel to the baseline).

As for the image on the L, his left (front) foot is parallel to the baseline (BL). His front knee is turned away a little bit from that. His hips are turned less than 45° away from the BL. Perhaps a bit more than 30° turned from the BL. But his chest is turned more than 45°, perhaps close to 60°, away from the BL.

This is the separation angle that I referred to in the posts above. The research studies from experts, Bruce Elliott and others also talk about this separation angle (the offset orientation of the hips wrt the chest or shoulders). The image was from the USPTA / RaquetFit article below which discusses this in a slightly different manner. He talks about multi-segmental rotations (saying that the hips and chest are not aligned or rotated quite the same)

No Coil Serve Characteristic | Article | Racquetfit

In our opinion, if you have an athlete who wants to increase their coil, the most important thing you can do is to determine whether the issue is technical or physical.

www.racquetfit.com

 

[a12345]

Wow, can we possibly be looking at the same images? I've developed a pretty decent eye over the several decades I've been coaching tennis. But I don't believe really it takes that much of a well-trained eye to see that, for the player on the R, both the hips & chest are oriented in nearly the same direction -- pretty much directly toward the side fence (parallel to the baseline).

As for the image on the L, his left (front) foot is parallel to the baseline (BL). His front knee is turned away a little bit from that. His hips are turned less than 45° away from the BL. Perhaps a bit more than 30° turned from the BL. But his chest is turned more than 45°, perhaps close to 60°, away from the BL.

This is the separation angle that I referred to in the posts above. The research studies from experts, Bruce Elliott and others also talk about this separation angle (the offset orientation of the hips wrt the chest or shoulders). The image was from the USPTA / RaquetFit article below which discusses this in a slightly different manner. He talks about multi-segmental rotations (saying that the hips and chest are not aligned or rotated quite the same)

No Coil Serve Characteristic | Article | Racquetfit

In our opinion, if you have an athlete who wants to increase their coil, the most important thing you can do is to determine whether the issue is technical or physical.

www.racquetfit.com

If you stand side on both feet next to each other shoulder width apart then being "in line" would be everything parallel to the tram lines.

But if you step your right foot back, to stay "in line" everything should now be pointing towards the net post.

Being in line means you should be facing back 45 degrees because your hip is now at an angle.

So if you take one step back with your right foot your natural hip position has turned 45 degrees, and so your upper body must also be angled back 45 degrees to stay in line.

 

[a12345]

Maybe its a difference of use of terminology because in this picture im saying McEnroe is all in line, everything is straight, aligned with the direction his arm is pointing at, whilst youre saying hes coiled.

If you draw a line along the tips of his feet and then draw another line from his arm holding the racket all the way down his back, the 2 lines are parallel and in line with each other.

 

[Dragy]

If you stand side on both feet next to each other shoulder width apart then being "in line" would be everything parallel to the tram lines.

Preparing to serve players stand more like frozen during walk, not next to each other shoulder width apart. You should determine alignment with reference to where knees and toes point, not as a simple line from one heel to the other.

 

[SystemicAnomaly]

Maybe its a difference of use of terminology because in this picture im saying McEnroe is all in line, everything is straight, aligned with the direction his arm is pointing at, whilst youre saying hes coiled.

If you draw a line along the tips of his feet and then draw another line from his arm holding the racket all the way down his back, the 2 lines are parallel and in line with each other.

John Mcenroe is crazy example JM is an anomaly. Nobody has served this way for 40 years except JM himself. Even during his heyday nobody else was serving like that

 

[SystemicAnomaly]

If you stand side on both feet next to each other shoulder width apart then being "in line" would be everything parallel to the tram lines.

But if you step your right foot back, to stay "in line" everything should now be pointing towards the net post.

Being in line means you should be facing back 45 degrees because your hip is now at an angle.

So if you take one step back with your right foot your natural hip position has turned 45 degrees, and so your upper body must also be angled back 45 degrees to stay in line.

Except for your JM example I cannot think of very many modern servers, offhand, who turns their hips much more then 30° away from the BL. A few might get close to 45° but not that many, I suspect. With my fairly standard platform stance, my hips turn less than 30° away from the BL while my torso turns at least 45° away.

About the only way I can get my hips to turn more than 30° away is to angle my front foot parallel to the BL and angle my back foot 45° or more toward the back. But, in my normal platform stance, my back foot is fairly close to parallel to the BL.

Take a look at a modern elite server, RF. His hips barely turn back from the BL at all (they are almost parallel to the BL). But look at the top letters on his shirt. It should be evident that his chest is turning 45° or more away from the BL

Please not post a serve video of Stan Wawrinka. While he can serve very big serves he is a poor example for other players who wish to serve big serves. His minimalist mechanics can be detrimental to your shoulder health.