Serve From The Knee Practice
- Thread starter Raul_SJ
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Pete Player
Hall of Fame
Coil and uncoil is really minor compared to the instructional vid.
Do you get that feel of squeezing your buttocks together?
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Do you get that feel of squeezing your buttocks together?
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Raul_SJ
G.O.A.T.
I think you're right about the coil. Was focused on getting the toss and brushing upwards correct...
Might be better to choke up like Jeff is doing and get racquet in same starting position as Jeff (My starting racquet position is too much behind the back).
Have no idea what you mean about squeezing buttocks.
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Pete Player
Hall of Fame
...
Might be better to choke up like Jeff is doing and get racquet in same starting position as Jeff (My starting racquet position is too much behind the back).
Have no idea what you mean about squeezing buttocks.
I forgot to mention the grip, choking it some would be good not to hit the ground.
The drill was named ”dirty dipers”, to coil and uncoil, you need support from the clutes. [emoji6]
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SinjinCooper
Hall of Fame
The whole point of serving from the knee(s) is to isolate the upper body movements from the lower body, so that you're maximizing both what you're getting from the upper body, as well as your understanding of how you're using it.
You're not using it at all. Literally only your arm is moving. Which is why the ball is reaching the fence on the fifteenth bounce, with no spin. The dirty diaper follow through is trivia until there's a throwing motion present.
You're not using it at all. Literally only your arm is moving. Which is why the ball is reaching the fence on the fifteenth bounce, with no spin. The dirty diaper follow through is trivia until there's a throwing motion present.
The point of serving from the knees is to grasp the idea of swinging up on the ball to get spin. When you are on your knees the contact point is so low that it would be impossible to hit a flat serve and get it in so the low contact points helps you to understand the idea of swinging the racket up and to the side.
FiReFTW
Legend
Exactly!
weelie
Professional
This is my understanding too. But personally, I don't like this exercise, never helped me any.
Pete Player
Hall of Fame
Yet my knees don’t aggree with this excercise, the vision from underneath the net tape has been huge help to me.
When you stand up after a handfull of kneeled serves, it seems ridigulously easy to serve into the box.
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vectorthurm
Rookie
I wonder if the better drill is to break out a higher net so you can get the benefits of having to serve up and spin in yet you can still use legs and be closer to normal serve.
Can do this laying down for an even better drillTrying to learn the kick and do the "Dirty Diaper" drill. I think my contact point at 12 o'clock is ok.
Anything else to improve?
Chas Tennis
G.O.A.T.
What does hit up mean?
1) the racket head goes up
2) the hand goes up
3) the ball after impact goes up
4) 'up' is only a feeling.
5) other
For what type of serve?
SystemicAnomaly
Bionic Poster
@Raul_SJ
Have you done this drill recently? Surprised that @Chas Tennis or someone else didn't mention the WTE. When the ball toss is at its peak, you've opene up (rotated) your racket face so that it is skyward rather than staying "on edge". Don't see this with Jeff's implementation.
I've had quite a few of my students hitting serves over the fence. Usually, we stand outside of the court and hit the ball over the fence into the court.
Have you done this drill recently? Surprised that @Chas Tennis or someone else didn't mention the WTE. When the ball toss is at its peak, you've opene up (rotated) your racket face so that it is skyward rather than staying "on edge". Don't see this with Jeff's implementation.
I've had quite a few of my students hitting serves over the fence. Usually, we stand outside of the court and hit the ball over the fence into the court.
Raul_SJ
G.O.A.T.
Have not tried this drill recently. This one looks okay to me. No WT?...
Also, I do notice that Jeff is not getting it in the box. Eventually with this knee drill, after we get a feel for upward swing path and staying sideways, we want to get it in the box and one bounce it to the fence? Sinjin was complaining about my many bounces to the fence.
One bounce, or even close to one bounce, seems very difficult. I suppose it is possible because Florian demonstrates a 100 mph knee serve, but Florian is a high level player.
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J011yroger
Talk Tennis Guru
You'd think I was great at serving from my knees if you saw how I blew my last match.
J
J
Does this drill help anybody? Did any pro do this when he/she was developing?
There are many drills which seem to be targeted towards aspects of the serve, like hitting up, tossing, pronation etc. But the biggest problem for rec players is getting the entire motion together for even the simplest slowest serve. That doesn't seem to be served (pun intended) by drills.
There are many drills which seem to be targeted towards aspects of the serve, like hitting up, tossing, pronation etc. But the biggest problem for rec players is getting the entire motion together for even the simplest slowest serve. That doesn't seem to be served (pun intended) by drills.
Chas Tennis
G.O.A.T.
I only consider the Waiter's Tray checkpoint for a high level serving technique at one location, the 'Big L Position' (or closest to). I use the Hi Tech tennis view as in the "Waiter's Tray Error" webpage just to show that I'm not alone. Often forum posters mention 'opening up' at other times during the serve. In the OP the serve is face to sky at Trophy Position, but not at Big L, and then gets to 'edge on' (to the ball) at the Big L and then moves edge at an angle toward the ball. ISR or pronation seems to be after the ball impact.
I am overwhelmed with learning about the high level strokes and don't spend much time studying lower level miscellaneous techniques of rec players. Progressions especially defy analysis, but I do compare some of them to the strokes. But I do believe that some progressions are useful. But which and why? I keep asking questions. Like what does "hit up" in post #14 mean? There are hardly ever any answers or links.
If poster's comments seem to conflict with what I've seen in high speed videos I often post about it.
The progression in the OP is nothing like the high level service motion as anyone can see by looking at high speed videos of the serve and comparing.
Now that I have just looked at the OP. It does show the principle of how the racket contacts the ball and rises. The arm seems near straight and the angle between the forearm and racket is rapidly changing to make the racket rise, that's great. If that progression is advertised as somewhat simulating ball string contact, that is very good, makes complete sense and useful.
But if readers/viewers misunderstand and think that the progression simulates a serve or its real contact then the problems start. First, there is little ISR leading to impact in the OP progression. ISR looks to be after impact. Impact really includes much more forward motion than is in the progression. Not only that but it involves ISR which is understood by most forum regulars but not by many active tennis players. The progression without additional instruction can mislead. Also, if the student does not understand that the service motion includes ISR and other things they probably will go toward the ball with an angle on the racket face as in the progression as in Raul_SJ's motion and NO ISR. In poster's serve videos, I see that edge-at-an-angle-to-the-ball approach in some of their slice and kick serves. (See recent argument with 5263.) Do the progressions spell out to the viewer what is being addressed and what is being completely left out and why?
PS (our perpetual issue) -
1) Progressions are for instruction. I'm not an instructor.
2) I believe in throwing a ball up as Pat Dougherty describes it in a video as a very good progression and simulates the ISR on the tennis serve. I have seen that throwing ISR is similar to serving ISR in high speed videos. So far I believe just that one progression.
3) Throwing a racket likely has value as many experienced instructors use it. But I don't understand that progression yet.
4) I don't accept most progressions when the rational for doing them is not described and they do not simulate serve motions as seen in high speed videos. Also, many of the progressions are not widely used.
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Raul_SJ
G.O.A.T.
1. I'm not seeing much difference between the high level player's Jeff's knee serve and my knee serve.
2. Is Jeff's ISR/Pronation acceptable to you?
3. Being on your knees forces you to get the toss above your ahead and remain sideways and not face forward too early.
Again, I do not see the difference between the high level player's Jeff's knee serve and my knee serve. As for ISR/Pronation, I think it has been discussed here and the consensus was that pronation is delayed for a slice serve relative to flat. ISR delayed too?
The delayed pronation might also apply to kick as well?
Chas Tennis
G.O.A.T.
1. I'm not seeing much difference between the high level player's Jeff's knee serve and my knee serve.
2. Is Jeff's ISR/Pronation acceptable to you?
3. Being on your knees forces you to get the toss above your ahead and remain sideways and not face forward too early.
Again, I do not see the difference between the high level player's Jeff's knee serve and my knee serve. As for ISR/Pronation, I think it has been discussed here and the consensus was that pronation is delayed for a slice serve relative to flat. ISR delayed too?
The delayed pronation might also apply to kick as well?
I looked at the video in the OP. It is blurry but I don't see the ISR before impact, my guess is that it is edge at an angle to the ball going up. I can't see ISR on that first OP video. Frames subject to interpretation because of the motion blur.
I did not look at the Jeff gif or video. I never considered what a 'high level knee serve' progression might be. A high level serve technique is mosty what succeeds in the top 100 ATP regarding technique, but also a lot of similar biomechanics but lower performance serves with the a very similar technique. In other words, less jump, less take back, less muscle stretch, timing not as effective, not as much ISR rotation angle before impact,...........
For the post #20 gif is that you? The gif moves too fast to examine. I can't see the ISR but it might be there. Can you display the last 4 or more frames leading to impact especially in an array of 8 pictures? Or extract the frames of the gif? Or you could display the gif using 3 seconds for each frame. Same for Jeff gif if you want to compare.
"I think it has been discussed here and the consensus was that pronation is delayed for a slice serve relative to flat." I don't agree. Have any references?
"The delayed pronation might also apply to kick as well?" I would not agree with that but I have seen some serves where that might be the case. Needs more careful observations to see percent, details and effectiveness if the serve. Impact occurs below the peak that the racket will reach for the kick serve. That can be done in more ways than one: jump higher, have the arm more vertical as seen from behind (as is seen). Or to let the ball drop lower than. It is not the actual height but impact must occur when the racket is still rising. Not easy to describe clearly in words see videos of impact. I've posted clear kick serve impacts but find others also.
See Salazar overhead composite pictures by Toly. Or FYB videos.
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SystemicAnomaly
Bionic Poster
Puzzling that Novak had this much trouble with this drill. Todd and Jeff make it look easy. I was able to execute this drill w/o much trouble at all. I've had intermediate students doing the same drill with less problems that Novak appears to be having in this video. It appears that He was reluctant to do this exercise. Or was he, in part, hamming it up?
It might have been this public humiliation that resulted in Novak dismissing Todd as his serving coach.
.
Raul_SJ
G.O.A.T.
What is Todd trying to show Djok? It must be something more complicated than Jeff's knee drill.
Djok is falling over totally off balance. Good grief.
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Hmgraphite1
Hall of Fame
Looks like Jeff is "opening up" shoulder into a deeper esr at the toss and therefore gets more isr "up" into "throw"1. I'm not seeing much difference between the high level player's Jeff's knee serve and my knee serve.
2. Is Jeff's ISR/Pronation acceptable to you?
3. Being on your knees forces you to get the toss above your ahead and remain sideways and not face forward too early.
Again, I do not see the difference between the high level player's Jeff's knee serve and my knee serve. As for ISR/Pronation, I think it has been discussed here and the consensus was that pronation is delayed for a slice serve relative to flat. ISR delayed too?
The delayed pronation might also apply to kick as well?
Chas Tennis
G.O.A.T.
Worked on https://ezgif.com/. Nice free application to make or change gifs. Used Snipping Tool to copy the screen and get a .jpg.
1) To Impact. Only one or two frames, 30 fps, were in the gif covering from the time ISR normally starts to impact. The orientation of the two red lines has not changed nearly as much as it would have if ISR had rotated the upper arm enough as in a high level serve.
2) After impact. But the ISR and pronation from impact to the last frame is very considerable. 90 d? Most ISR occurs after impact.
3) There is little movement of the shoulder up and forward.
This progression can teach something about the racket shaft angle changing during the time that the racket strings contact the ball.
I would expect this progression to mislead many players into believing that for the serve the racket should go toward the ball with the edge leading and at an angle and with little ISR. For a high level serve the racket head rotates toward the ball because the upper arm rotates from ISR (plus some pronation). In my opinion, an instructor and player would have to understand this.
Rare Fuzzy Yellow Balls overhead videos processed by Toly into composite pictures.
Protractor measurements for these 3 pictures:
1) Slice - 70 d. racket head rotation.
2) Flat - 82 d. racket head rotation.
3) Kick - 54 d. racket head rotation.
The racket appears to have rotated more at the beginning.
Note - We should see overhead camera views of some current ATP player serves.
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Hmgraphite1
Hall of Fame
So you can see you don't use your shoulder on upward swing path. Note how jeff puts his shoulder "back" and exposes the "soft side" of his arm (the part that rarely faces the sun) toward the sky. Especially his forearm. This motion puts shoulder into esr, stretches isr muscles, pectoral etc imhoHave not tried this drill recently. This one looks okay to me. No WT?...
Also, I do notice that Jeff is not getting it in the box. Eventually with this knee drill, after we get a feel for upward swing path and staying sideways, we want to get it in the box and one bounce it to the fence? Sinjin was complaining about my many bounces to the fence.
One bounce, or even close to one bounce, seems very difficult. I suppose it is possible because Florian demonstrates a 100 mph knee serve, but Florian is a high level player.
Raul_SJ
G.O.A.T.
Yes I agree that I have not achieved ESR and steep racquet drop. Not that easy for me as should is not particularly flexible. If I focus on too many things it screws me up.
Was trying to focus on few things first: hitting up, staying sideways, approaching edge on...
Now trying to figure out how to fix the ISR/Pronation issue Chas pointed out. If I understand correctly my isr needs to be earlier. Right now isr is happening mostly after contact...Bit confused on this as Jeff says Pronation is not something one has to think about. It should happen naturally if one has the proper setup before and follow through after.
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Hmgraphite1
Hall of Fame
Start with having your elbow up as the highest point of your arm at the racquet drop between photos 2 and 3 in your series above. You'll have more isr if you do this.
vectorthurm
Rookie
Have not tried this drill recently. This one looks okay to me. No WT?...
Also, I do notice that Jeff is not getting it in the box. Eventually with this knee drill, after we get a feel for upward swing path and staying sideways, we want to get it in the box and one bounce it to the fence? Sinjin was complaining about my many bounces to the fence.
One bounce, or even close to one bounce, seems very difficult. I suppose it is possible because Florian demonstrates a 100 mph knee serve, but Florian is a high level player.
Man Salzi is just fluid! The thing to key in on is how his upper body works together and his arm motion shape. His finish is beautiful, pronates over with elbow high, left hand comes down. At this point, it’s good to note that he’s LEFT HANDED!! Skillz
Chas Tennis
G.O.A.T.
Look at the handle of the racket at 2:46. It is hard to tell the racket motion around impact because of the motion blur but the ISR and pronation after impact are clearly seen by looking at the hand and handle. ISR and pronation seem late compared to a serve. There are no rules for what a progression should look like. High speed video without motion blur would show the racket motion.
Best video I've seen in a while, good sh*t mate
Raul_SJ
G.O.A.T.
Will take a look. Had assumed that a pro would be replicating his actual serve ISR in the knee drill as well. Don't see why the ISR would be late on the knee serve compared to his real reseve.
Chas Tennis
G.O.A.T.
For the last few years I have been looking at progressions to see if they simulate the real stroke or part of the stroke. The only one that I found that appears to simulate any stroke is the upward ball throw as described in the Pat Dougherty video. ISR seems to be simulated even to the tilt of the upper arm. The simulation is identical to the serve regarding the bend in the elbow and I assume many other details. All the other progressions, as far as I could tell with the available video, did not simulate the serve.
I have also look at demos from instructors that seem to show a part of the serve or other stroke and found that they very often don't and sometimes the demo has clear flaws. Those same instructors often then hit a stroke that looks correct.
Don't take progressions or demos literally.
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Raul_SJ
G.O.A.T.
There is a Florian video where he is serving 95mph from the knees. Given the high speed, I would expect this knee serve to exactly simulate the ISR of a real high level serve.
If someone has a link to the Florian knee serve video please post.
Pete Player
Hall of Fame
1) Indeed it goes,
2) Absolutely, and as high as possible straightening out before impact,
3) Not necesserily, but on certain serves it does,
4) No it is not,
5) Yes. Throwing the racket towards the ceiling (zenith if you like) will eventually make it ”flip” horizontal.
Any kind.
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On pain meds - all contributed matter and anti-matter subject to disclaimer
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SystemicAnomaly
Bionic Poster
Couldn't seem to find the vid you're asking for. Was it really Florian? Or perhaps Tomaz M (FeelTennis) or someone else with a East Euro accent?
Perhaps the Florian video is in here somewhere. Looked for a while but didn't see it. But he does have a ton of vids here: https://www.youtube.com/user/OnlineTennisLessons/videos
Raul_SJ
G.O.A.T.
Yes, I am sure it was Florian. Used to pop up a million times as a commercial when I was browsing YouTube. I would then click "skip ad" to skip the Florian commercial and view the video I was actually interested in... But it might not be a public video. Maybe it is only part of his paid serve course.
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Raul_SJ
G.O.A.T.
Yes, "Hitting Up" cue has a clear meaning in the kick serve.Have to let the toss drop lower than on a flat serve. Only then can you impart the topspin by brushing up with the racquet.
Although I do agree with Chas that "Hitting up" cue is more ambiguous on a flat serve.
Pete Player
Hall of Fame
I would say toss needs to be further back your stance on kick-serve, and contact more ”underneath” the ball than on slice or flat, while flat contact should be more in the front of your body and hit probably a touch down. Brushing up would ring the bell on kick-serves. If you hit up, the ball starts off upwards and never take enough spin. That might even be one of the culprits, people WT the ball without pace nor spin just darting the ball into the box.
Hitting up is not correct, unless you wish to hit it up. But ”throwing up” will draw an image to me, where I try to throw the racket to the ceiling, which woun’t ofcourse happen, cause you grip it on the handle.
The throwing motion ends into pronation, and the racket flips on the ball, when your levers have stretched out and hand cannot move up anymore. If you direct the hand forward to make the ball go towards the other end of the court, you lose the loose and automatic release, which is key attribute in a top-level serve.
”Throwing up” in quotation for obvious other images, that may occur.
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On pain meds - all contributed matter and anti-matter subject to disclaimer
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Pete Player
Hall of Fame
Inspite the in front aspect this only shows, there is room for getting better even with the top pros.
The first few tries looks to me as he is doing the same with his upper body as he used to do when serving standing. Nodding forward, which is really not, what you want to do in a good serve.
Service motion is more of an upright move than forward one.
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