I have not found a way to hit the ball harder than a proper first serve technique. If it's really possible I would like to know how. I agree with you that hitting hard is easy and doing it with accuracy is harder, but if you can hit the ball harder with some other technique than the one you serve with then I think there might be some element lacking in your serve. It might not be technique it could just be something to do with shoulder flexibility or some other issue, but I doubt that there is generically speaking a swing technique that can more effectively deliver power to a tennis ball.
Mystery of pronation on serve
- Thread starter FiReFTW
- Start date
I have not found a way to hit the ball harder than a proper first serve technique. If it's really possible I would like to know how. I agree with you that hitting hard is easy and doing it with accuracy is harder, but if you can hit the ball harder with some other technique than the one you serve with then I think there might be some element lacking in your serve. It might not be technique it could just be something to do with shoulder flexibility or some other issue, but I doubt that there is generically speaking a swing technique that can more effectively deliver power to a tennis ball.
Chas Tennis
G.O.A.T.
When the arm is near straight there are two rotations that add together to produce the rotation seen at the wrist.
1) pronation
2) internal shoulder rotation
Pronation can be seen by measuring the axial rotation at the wrist area and subtracting the rotation seen at the elbow area.
Internal shoulder rotation can be see by measuring the axial rotation seen at the elbow area. Look for the shadows that indicate the bones and tendons at the elbow. Need direct sunlight and a very fast shutter speed to reduce motion blur. A piece of tape can be placed on the upper arm at the elbow, on an epicondyle is a good spot.
Friedman Whip
Professional
I try to stay out of discussions about pronation, but I will ask this question of all those who have an understanding of it. When pronation is done to optimal effect what kind of spin does the ball have? I don't think I've seen anyone mention that.
Chas Tennis
G.O.A.T.
To simplify -
What is being used is about 70 d ?? of powerful internal shoulder rotation before impact - ISR caused by muscles stretched in the earlier serve motions. ISR involves the largest muscles attached to the arm, the lat and pec & others. Pronation involves much smaller muscles in the forearm. For power it is likely that bigger muscles will be involved = ISR for serving and pitching.
ISR after impact, in the follow through, can depend on how the server activates his muscles to slow down, uses a bend in the elbow or other. It varies and there are options for the server.
What is being used is about 70 d ?? of powerful internal shoulder rotation before impact - ISR caused by muscles stretched in the earlier serve motions. ISR involves the largest muscles attached to the arm, the lat and pec & others. Pronation involves much smaller muscles in the forearm. For power it is likely that bigger muscles will be involved = ISR for serving and pitching.
ISR after impact, in the follow through, can depend on how the server activates his muscles to slow down, uses a bend in the elbow or other. It varies and there are options for the server.
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Chas Tennis
G.O.A.T.
When you say "pronation" do your mean internal shoulder rotation plus pronation as defined in biomechanics and kinesiology? These terms can be Googled for pictures and videos.
Does anyone have a problem with discussions using undefined terms that have different understandings for the posters and readers. Defined terms seem a basic requirement for communication. If the meanings of terms can't be stated by the users, is that a problem?
I have a hard time seeing pronation as it is defined in kinesiology in the lead up to impact for the tennis serve. Elliott states that about 5% of forward racket head speed is produced by pronation at impact. 40% by internal shoulder rotation. The see 5% you need markers and some very careful camera work on the elbow and wrist area. Too difficult for me. ISR can be seen by the elbow shadows. The work of tennis biomechanics researchers with their clear descriptions of how they were measured should always be considered.
'Pronation' is done to best effect and observed for the high level kick serve, slice serve and flat serve. So is ISR.
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Curious
Talk Tennis Guru
I have a pretty good serve but I tend to pronate too early. It's probably an instinctive urge to open the racket face up because you will be hitting with that side not with the edge so I guess it requires deliberate training. I doubt it comes naturally as part of a good throwing motion. A progression exercise may work ( will try it myself first ) in that you hit serves with the edge of the racket with a conti grip for a while, then add pronation ( open up racket face) gradually and try to do it at the last moment as otherwise it adds nothing to a serve.
So far so good...
I'm not sure I follow 4,5 and 6. I guess it depends on what you mean by swinging sideways.
I would say you should be looking up at the ball and swinging up with the edge of the frame headed towards the ball but slightly to the right of the ball for a right hander. This is still not a great description because if you are maximizing the shoulder rotation then the angle of the frame will be changing as you swing upwards going from the outside of the shoulder at the beginning to in front of the body at contact and then finishing roughly 180 degrees from where it started.
I'd agree with these cautions. If you're doing it wrong there can be consequences to your arm health for sure.
I always start my students out slowly. We usually start at the service line and don't even do the swing. Just hold the arm straight up with the top of the racquet pointed roughly at the back fence. The we rotate the arm so the racquet swings pretty much like a saloon door with the strings passing over head. Once we determine where the ball needs to go so the strings will make contact with it, we toss and turn the arm trying to get the strings slightly above center on the back of the ball so it goes into the service box.
For beginners we may spend the full 20-30mins I allocate in a class for serve just trying to get the toss in the right spot. The people that don't take the toss part seriously fall quite far behind in a few lessons. Some people just can't see the toss as critical and it works against them. They don't believe me when I tell them it's absolutely the most important part of the serve. Everything else follows the toss.
The people that get the toss right and work on that turn are hitting serves in the box from the baseline with only a handful of hours practice usually. That's with basically no swing. Once they get to that point we start adding the other elements in. The trick is to go fast by taking it slow. I always try to get people to go back a step if things go awry. It's easy to mess up one of the first elements when adding something new. A lot of people are stubborn and want to keep pressing forward even though something new is affecting a previous element. If you can self assess well and accept when you need to go back and retrain some fundamental part of your serve then you will progress much faster overall.
Friedman Whip
Professional
Let me rephrase my question. When Sampras hit that wonderfully effective snapped pronated serve of his (the one that has been shown in videos so many times), what spin was put on the ball?
r2473
G.O.A.T.
What you say is accurate. And as I say, this type of technical explanation will be helpful to some and not to others.
For me, it wouldn’t mean much if I didn’t understand it already. But since I do, I can say it is quite accurate
I use pronation as the term for rotation of the arm in the serve, both upper and lower. It might not be technically correct, but I think that's the way most people use it for serving.
Also, for me personally I can "pronate" (upper arm only), a full 180 degrees judging by my hand. I place my hand out in the "gimme five" position with the palm up and I can fully rotate my hand over where the palm is down with no rotation of my elbow.
My upper arm can rotate roughly 90 degrees judging by the point of my elbow.
I think one of the most important aspects of pronation (whole arm rotation) on the serve is that it allows you to swing harder because you have a way to dissipate the energy of the swing that won't kill your joints. You just can't safely swing as hard if you're not using all of that rotational space to let the racquet decelerate after impact. Of course the most important part is that you make more optimal use of the frame as a lever to generate racquet speed.
Topspin. When you hit that serve like he does the ball jumps up off the court and continues rising all the way to the fence. It's super hard to handle. When I'm on with my serve and hit that flat one it hits the back fence above that middle horizontal post. I hit a guy in the chest one time who was standing just about two steps back of the service line. He was my height so the ball was probably already close to 4ft high only about 8 ft behind where it bounced. I'm not sure how high that one would have hit the fence at. I was pretty pumped as it was a close doubles match and those guys were playing all sorts of games, like rushing in on first serves, shuffling feet, and generally trying to find a way to mentally game us. It didn't work out for them that day. I think the adrenalin helped make that serve a doozy. I doubt I could hit one that hard on the practice court.
r2473
G.O.A.T.
I can hit harder by going “through “ the ball. Hitting “out” at it. I’d be surprised if most people couldn’t
r2473
G.O.A.T.
My 4, 5, and 6 are trying to give a “feel” for what ISR and pronation are. And to not swing “through” the ball as coach MaLennan says. Just trying a different mental picture. I think this is what it “feels” like. Especially if you are used to hitting “out and through” the ball as many people are
Obviously you won’t literally be hitting the ball toward the fence.
Curious
Talk Tennis Guru
Why wouldn't you swing through the ball if it is meant to be a flat first serve?
No, even with pronation, flat serves are hit through the ball.
Sent from my SM-G935V using Tapatalk
So you can hit it harder by hitting through the ball without pronation than you can hitting with pronation? So the first one would be just the arm swinging the racquet through the ball?
The thing about pronation is you get the momentum of swinging the arm plus the rotational lever of the frame. If you link the racquet and the arm together by having them move as a unit you lose that rotational lever. That's a very significant chunk of racquet speed to give up.
Chas Tennis
G.O.A.T.
How to measure the range of internal and external shoulder rotation. Angular POSITIONS. Bending the elbow to 90 degrees is used to measure the reclining subject. Note the defined 0 degrees.
Similar videos exist for measuring the joint motion pronation.
But there is a complication, an ambiguity - the same terms are used for both POSITION and MOTION even in technical publications.
POSITIONS (as measured above).
External Shoulder Rotation Angle - angle measured from a defined reference direction (0 degrees).
Internal Shoulder Rotation Angle - angle measured from a defined reference direction (0 degrees).
MOTIONS
External Shoulder Rotation - any joint motion in the direction toward the max external shoulder rotation angle. (The angle of the joint does not matter.)
Internal Shoulder Rotation - any joint motion in the direction toward the max internal shoulder rotation angle.
Usually the context makes the meaning clear.
It took me a few years to realize what was being done because most introductory material does not mention the ambiguous usage.
For the tennis serve the motion of internal shoulder rotation maybe has 70 degrees - more or less - before impact - and >70 after impact. Pronation and ISR together with a straight arm about 260 d for me voluntary motion. Try it.
On the forum the MOTION meaning is usually meant. Many posters do not have a clear idea of the defined terms but use the terms anyway because they have been used in past decades by mistake. This mess was straightened out over 20 years ago and made crystal clear for tennis biomechanics of the serve. See publications of Elliott, Marshall etc.
Should the incorrect terms be used in discussing tennis strokes. See OP title. Why?
Similar videos exist for measuring the joint motion pronation.
But there is a complication, an ambiguity - the same terms are used for both POSITION and MOTION even in technical publications.
POSITIONS (as measured above).
External Shoulder Rotation Angle - angle measured from a defined reference direction (0 degrees).
Internal Shoulder Rotation Angle - angle measured from a defined reference direction (0 degrees).
MOTIONS
External Shoulder Rotation - any joint motion in the direction toward the max external shoulder rotation angle. (The angle of the joint does not matter.)
Internal Shoulder Rotation - any joint motion in the direction toward the max internal shoulder rotation angle.
Usually the context makes the meaning clear.
It took me a few years to realize what was being done because most introductory material does not mention the ambiguous usage.
For the tennis serve the motion of internal shoulder rotation maybe has 70 degrees - more or less - before impact - and >70 after impact. Pronation and ISR together with a straight arm about 260 d for me voluntary motion. Try it.
On the forum the MOTION meaning is usually meant. Many posters do not have a clear idea of the defined terms but use the terms anyway because they have been used in past decades by mistake. This mess was straightened out over 20 years ago and made crystal clear for tennis biomechanics of the serve. See publications of Elliott, Marshall etc.
Should the incorrect terms be used in discussing tennis strokes. See OP title. Why?
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mbm0912
Hall of Fame
I measure mine before every serve.
r2473
G.O.A.T.
This is why I don’t often engage in discussions here.
Take what I’ve said, however you read it, for what it’s worth to you. I think what I’m saying is wrong. It doesn’t make sense. If I were reading my posts, I’d ignore them.
Yeah, this is difficult. There is ESR, ISR, supination, and pronation all involved in a high level serve.
Also I don't know what upper arm rotation that is in line with pronation would be called. I'm not talking about ISR or ESR as described in the video. What I'm talking about is how your elbow goes high if you put your arm straight out in front of you and do a thumbs up to thumbs down rotation.
So whatever that is we need to add that as well.
Ok, sorry to bother. I was just trying to understand where you were coming from. I am pretty sure I didn't get what you were saying the way you intended that's why I restated to try and clarify how I was reading it.
Anyway, I know it's very difficult to try and engage in these sorts of discussions without being able to demonstrate things. Probably more than half the people I coach can't replicate something even after seeing it demonstrated in person. A lot of people don't have a well trained mental model of how their bodies move. Sometimes it requires physically positioning someone and letting them feel what it's like to be in that position before they get it. Since most of us rarely try to write out how we're doing things that's an even harder challenge for many of us.
Kudos to @Chas Tennis for trying to educate on terminology. I fear it's a losing battle though since it's so complicated and verbose to talk in "proper" terminology.
Curious
Talk Tennis Guru
That's ISR, mate.
This is confusing. That's what I would have said before watching the video. Then I watched the video. Then I was trying to feel my shoulder move as I went through the measuring positions from the video. Then I tried feeling my shoulder move as I went through positions on my serve motion. The way my shoulder joint moves while my arm is rotating in the serve position feels different than what it feels like when I go through the motion in the video.
Of course when you posted I watched the video again and realized she mentions the motion I'm talking about right at the beginning briefly while she's standing.
So it felt to me like it should have different names, but they are both called ISR and ESR just in different planes of motion. So whether or not there is any real difference in the function of the joint in those different planes I am not sure. It might just be the way my shoulder feels to me. It could be imagined too I guess.
So anyway ignore my request for a new term. I think ISR is what I was feeling just in a different position.
Thanks for pointing out my error.
onehandbh
G.O.A.T.
This slow motion video of Federer's serves is one of the best I've seen. Really show what happens with with the legs/body/shoulder/arms.
Also, in this second video, which is shot almost perfectly from the side along the baseline. You can see the shoulder over shoulder motion happening, resulting in this upper body to be facing toward the net a bit at contact.
Federer's toss is perfect!
Also, in this second video, which is shot almost perfectly from the side along the baseline. You can see the shoulder over shoulder motion happening, resulting in this upper body to be facing toward the net a bit at contact.
Federer's toss is perfect!
heninfan99
Talk Tennis Guru
It's very natural to most but you might have to do some pronation drills.
Morch Us
Hall of Fame
Good video.
Chas Tennis
G.O.A.T.
If you do a thumbs up to thumbs down the elbow does not go up or down it stays at the same location.
Thumbs up to thumbs down could be only pronation if you hold your elbow mass still. But it is likely to be ISR plus pronation because it is hard to hold the elbow mass still. Grab the elbow mass to hold it still.
To isolate pronation from ISR bend the elbow at 90 d.. Bend elbow and do pronation. Bend elbow and do ISR. These joint motions are completely separate.
But when the arm is near straight pronation and ISR produce the same visible rotation of the wrist area. This is the whole origin of the mistake made decades ago.....of calling an important part of the service motion 'pronation'.
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Chas Tennis
G.O.A.T.
That is the whole idea - a swing plus a 'rotation' from ISR.
D
Deleted member 54265
Guest
YES
Toss hight is another question, my personal preference is Ito have a high ball toss, then I have more time and dont rush my swing.
Chas Tennis
G.O.A.T.
No. The shoulder will be moving. So at the toss release, the toss will not be aimed over the right shoulder.
The instruction to 'Toss over the head for the kick serve' is not correct because the head moves forward. View a serve from the side and observe where the shoulder is when the toss is released.
There is quite a range of forward motions observed for high level serves. Raonic moves forward a lot. Federer not much. They are tossing to where they want to hit it. Look at high speed videos.
I can't get all the way to thumbs down when I hold my arm straight out and turn. So going all the way forces some ISR for me. Might be different for others.
I figured out my mistake on the terms after looking at the video again. I pretty much agree with your other points. I think I might just start calling it PSAR (pro style arm rotation) from now on.
FiReFTW
Legend
Yea I was thinking the perfect contact is after you serve and when ur racquet contacts the ball, it should be somewhere around ur shoulder, when looking left and right along the baseline, and a bit infront.
FiReFTW
Legend
I actually like a lower toss, so I can have a nice fluid motion and fast motion that also gives less time for the opponent to pick up anything, slightly above the contact point is perfect, so the ball starts to drop a bit, and also the ball won't have much speed so its easier to time, Federer does it perfectly.
D
Deleted member 54265
Guest
D
Deleted member 54265
Guest
Yes, over the right shoulder is a good spot (x axis) (when right handed and standing sideways when making the toss) and then also into the court about 1/2 meter or more (y axis). Hope this makes sense
I was sitting parallel to the baseline at the US open and watched del Potro serving. It was crazy how far he tossed the ball into the court, my guess about 1 1/2 meter (5 feet), also a high ball toss (z axis).
Chas Tennis
G.O.A.T.
What type of serve did he hit?
The problem during discussions and instruction is that your x,y,z description in not explained as you are doing. It is simplified to 'toss the ball over the head' or shoulder. Many take these over simplified words literally, as I have done in the past.
For most pictures or frames taken from ground level you can believe whatever you already believe. But from overhead views you can see how the head and shoulders move between toss release and impact. False - 'toss the ball over the head for a kick serve'. True - the ball is impacted more over the head for a kick serve. See the pictures below.
Mixing the times of
1) the toss release with
2) the time of the impact
as if they are the same time muddles and misleads because there is significant movement between the toss release and impact.
Toly composite picture of Frank Salazar serve, made from rare overhead Fuzzy Yellow Balls high speed videos. This picture is traditionally worth 2000 words. But on this forum it's priceless. Which post has a word description that describes this?
Salazar appears to be tossing the ball to where he wants to hit it.
Notice also that Salazar is not staying sideways on the kick serve as is often said. At impact his upper body is more sideways.
Describing tennis strokes in words is what keeps the Tennis Stroke Nuthouse alive.
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D
Deleted member 54265
Guest
What type of serve did he hit?
The problem is that your x,y,z description in not explained as you are doing during discussions. It is simplified to 'toss the ball over the head' or shoulder. Many take these over simplified words literally, as I have done in the past.
For most pictures or frame taken from ground level you can believe whatever you already think. But from overhead views you can see how the head and shoulder move between toss release and impact. False - 'toss the ball over the head for a kick serve'. True - the ball is impacted more over the head on a kick serve.
Mixing the times of 1) the toss release with 2) the time of the impact as if they are the same time muddles and misleads because there is significant movement.
Toly composite picture of Frank Salazar serve, made from rare overhead Fuzzy Yellow Balls high speed videos.
Yes I get your point, and it is a very good point.
In the images shown of the kick serve I see two important thinks:
1. The toss is almost at the axis of the right shoulder but out in front about 1/2 meter
2. Body position when hitting is facing the netpost and not the net. The serve is hit more sideways, and that is the key element to get the kind of pronation or ISR that @r2473 is descriping.
Cheers, T
D
Deleted member 23235
Guest
biggest issue i had, is realizing that when i was hitting a "beginner" slice... ie. contact at 3 o'clock, there is no pronation (like a sidearm throw)
heninfan99
Talk Tennis Guru
low toss?
D
Deleted member 23235
Guest
yeah lower toss (and out to the side)... ie. the arm only goes more horizontally out in a circle
like the earlier part of these progressions:
heninfan99
Talk Tennis Guru
The other parts of the serve are tricky for sure esp. finding the toss as you know.
watungga
Professional
Finding your height of toss.
Lightly close your eyes and have someone shoot a video of your serve. Just one shot from your back and another at your side.
Toss the ball and execute a perfect serve you like.
Playback the video and and calculate where you must toss the ball to achieve a perfect meet with the stringbed.
Your serve stroke must not be commmanded by your toss.
Lightly close your eyes and have someone shoot a video of your serve. Just one shot from your back and another at your side.
Toss the ball and execute a perfect serve you like.
Playback the video and and calculate where you must toss the ball to achieve a perfect meet with the stringbed.
Your serve stroke must not be commmanded by your toss.
FiReFTW
Legend
@Toby14 @r2473
Ive been doing shadow swings in my room to get the feeling, and ive really got the feeling down now! I feel how it should feel to do this full pronation now.
Tomorrow im going on the court and trying it out in practice, and hopefully it works as well as it does now! I just need to keep the same feeling and motion, and disregard the ball or where its going, to just get a feel for it.
My arm really feels even more relaxed and loose as before, it just flows through the motion and the full pronation is a very smooth thing, you just need to get a feel for it.
I feel like this is going to improve my serve quite a bit and a game changer!
Ive been doing shadow swings in my room to get the feeling, and ive really got the feeling down now! I feel how it should feel to do this full pronation now.
Tomorrow im going on the court and trying it out in practice, and hopefully it works as well as it does now! I just need to keep the same feeling and motion, and disregard the ball or where its going, to just get a feel for it.
My arm really feels even more relaxed and loose as before, it just flows through the motion and the full pronation is a very smooth thing, you just need to get a feel for it.
I feel like this is going to improve my serve quite a bit and a game changer!
r2473
G.O.A.T.
Do us all a favor and document your progress on this thread. problems you have, things you notice, adjustments you make. Things you thought you understood but see differently after trial and error.
I think this is very difficult for most people, so your experience could be helpful to lots of others because you'll be able to document your journey as it happens.
If you are feeling brave, post videos from time to time. I might try to post a video of my serve sometime too.
Good luck!!
D
Deleted member 54265
Guest
@Toby14 @r2473
Ive been doing shadow swings in my room to get the feeling, and ive really got the feeling down now! I feel how it should feel to do this full pronation now.
Tomorrow im going on the court and trying it out in practice, and hopefully it works as well as it does now! I just need to keep the same feeling and motion, and disregard the ball or where its going, to just get a feel for it.
My arm really feels even more relaxed and loose as before, it just flows through the motion and the full pronation is a very smooth thing, you just need to get a feel for it.
I feel like this is going to improve my serve quite a bit and a game changer!
Great - looking forward to hear your experience. Be patience, it takes some time to get the timing with a ball.
1 small thing that might help too: try to keep your body more sideways when making the hit (like in your first image)
Força Barça
FiReFTW
Legend
Yes, I will try my best, of course I like to help other people as much as possible.
