Too much knee bend on serve: anyone else?

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VeeSe

Rookie
Hey all,

So I have too much knee bend on my serve, making it really hard to keep up for the whole match (takes a lot of energy to explode up that much all match). It also makes it hard to be consistent if it's much harder to keep up as the match goes on. I'd like to transition to something more traditional, so I was wondering if anybody else had the same problem and what they ended up doing to get out of it. I don't really have any questions, I just wanted to know if anybody else was in the same boat.
 
TomT

TomT

Hall of Fame
VeeSe said:
Hey all,

So I have too much knee bend on my serve, making it really hard to keep up for the whole match (takes a lot of energy to explode up that much all match). It also makes it hard to be consistent if it's much harder to keep up as the match goes on. I'd like to transition to something more traditional, so I was wondering if anybody else had the same problem and what they ended up doing to get out of it. I don't really have any questions, I just wanted to know if anybody else was in the same boat.
Click to expand...
I wish I had your problem. :)

The solution to your problem is bending your knees a bit less. Right? So what's the problem? My suggestion would be to watch some of the good servers from, say, the '70s. They were hitting 110mph + serves (I'm guessing) without a ton of knee bend with 65 sq. in. face wooden racquets.
 
V

VeeSe

Rookie
Well, the timing is all different and I get way less power. I guess I have to focus more on the other aspects more, like staying loose, making the "bow" with the hips, and weight transfer. I just wanted to ask someone who made a similar transition what they focused on first and how long it took.
 
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The Meat

The Meat

Hall of Fame
Platform or pinpoint? When I had a platform serve I always had to bend a lot to get a consistent hard serve, so I also got tired quicker. I don't have to bend my knees as much on a pinpoint serve to get a lot of power, I fashioned it like Wawrinka's. It's very energy efficient.
 
V

VeeSe

Rookie
The Meat said:
Platform or pinpoint? When I had a platform serve I always had to bend a lot to get a consistent hard serve, so I also got tired quicker. I don't have to bend my knees as much on a pinpoint serve to get a lot of power, I fashioned it like Wawrinka's. It's very energy efficient.
Click to expand...

Platform. Thinking about switching to pinpoint, so thanks for the feedback.
 
HughJars

HughJars

Banned
Had the same problem. Platform stance, when I have too much knee bend I get too low at hitting point.

Just mentally thinking tall and ensuring your tossing arm is as high as possible helps me out. Watching vidoes of Djokovic and Tomic helped too. They stay tall. And cutting out the down swing of the racket arm also helped. (Kind of like Roddick and Tomic who seem to just come up with the racket arm)

With that tossing arm high, it subconciously prompts you to stay taller through the service motion with your legs and trunk.

Edit: Also, focus on moving into the court on serve, not having all your energy in a vertical plane (up and down). Helped my consistency and serve speed. Think about a standing high jump and a standing long jump. The long jump has less knee bend.
 
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V

VeeSe

Rookie
I'm able to get back to the normal hitting point fully extended, but it just takes a lot of energy/consistency when I start from a point where my knee is 4-5 inches from the ground (that's where all the power came from). I will take a look at Djokovic's slow motion service though! Could be something to what you're saying. Thanks.
 
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The Meat

The Meat

Hall of Fame
VeeSe said:
I'm able to get back to the normal hitting point fully extended, but it just takes a lot of energy when I start from a point where my knee is 4-5 inches from the ground (that's where all the power came from). I will take a look at Djokovic's slow motion service though! Thanks.
Click to expand...

I always have this video bookmarked if people are interested in a "tall" platform serve.

http://www.youtube.com/watch?v=mvbC9BcQDQg

Go to 0:10, very simple motion.
 
Raul_SJ

Raul_SJ

G.O.A.T.
Is it acceptable to bend the knees but not lift off the ground?

I feel more comfortable staying on the ground.
 
D

dominikk1985

Legend
VeeSe said:
Hey all,

So I have too much knee bend on my serve, making it really hard to keep up for the whole match (takes a lot of energy to explode up that much all match). It also makes it hard to be consistent if it's much harder to keep up as the match goes on. I'd like to transition to something more traditional, so I was wondering if anybody else had the same problem and what they ended up doing to get out of it. I don't really have any questions, I just wanted to know if anybody else was in the same boat.
Click to expand...

the revolutionarytennis guy said that you can bend the knees too much when you are just bending and not bowing your front hip into the field.

hw said the bow is more important than the bend and the bend is assisting the bow. there has to be a balance.
http://www.revolutionarytennis.com/step12_2.html
 
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C

Chas Tennis

G.O.A.T.
Raul_SJ said:
Is it acceptable to bend the knees but not lift off the ground?

I feel more comfortable staying on the ground.
Click to expand...

Thread - Kneeling Servers Hitting 125 MPH - Really?
http://tt.tennis-warehouse.com/showthread.php?t=414039

What does the leg thrust do?

It mainly stretches the internal shoulder rotators by forcing the shoulder joint up while the elbow is bent with the forearm and racket at about a 90° angle and back a little from vertical. When the shoulder joint rises the inertia of the forearm and racket causes the shoulder joint to externally rotate stretching the internal shoulder rotator muscles, mainly the pec and lat. You can see this stretching and how it is timed relative to the leg thrust in high speed videos. Watch for the upper arm rotation - that indicates internal or external rotation of the shoulder joint. https://vimeo.com/user6237669/videos

In addition to the leg thrust when the tossing shoulder is brought down and the hitting shoulder is rapidly raised while the trunk is rotated this also stretches the internal shoulder rotators (or maintains the stretch already there from the leg thrust). This motion is more complicated compared to the leg thrust's mostly causing the shoulder joint simply to rise. The leg thrust & trunk motions also overlap during the service motion.

These motions are easy to understand with a kinesiology reference such as The Manual of Structural Kinesiology. Thompson & Floyd. Older editions - recommend the 15th - of this popular college text are very reasonably priced now. .....used copies $0.99.......
 
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GoudX

GoudX

Professional
Your knee bend is only too much if you have gone lower than the lowest point that you can 'explode' out of. If your knees are going past 90 degrees it is probably too much. Otherwise it might be more of a strength and stamina issue.
 
P

ProgressoR

Hall of Fame
if you are bending so that your knees are 4-5 inches off the ground and not hitting 120mph plus then something is not working right....

I have seen guys hit serious serves with just average knee bend. Maybe the problem is not that you bend your knees, but perhaps you bend them a lot more than you need to/than can benefit you....?
 
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Chas Tennis

G.O.A.T.
Stretch Shortening Cycle and Maybe 90° (?) Knee Bend

The knee bend uses the stretch shortening cycle (SSC) as probably all rapid athletic motions do. The knees have to bend (body weight plus active muscle force), stretching the quads and maybe the glutes also. Then, in a very short time the legs fire back up using those stretched muscles (continuous motion without pause). The stretch shortening cycle has the characteristic that a stretched muscle must be shortened soon after stretching or the added force possible from the stretch will decrease and will be lost completely, in say, 1 second or maybe less. If you bend you knees and pause for a second you may not be getting anything from the SSC.

As a first guess, I would estimate from memory that many pro servers bend their knees about 90°. This is easy to observe for yourself on high speed videos.

(Many but not all Youtube videos will advance or go backward one frame using the arrow keys.)
 
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counterfeit25

Rookie
Chas Tennis said:
What does the leg thrust do?

It mainly stretches the internal shoulder rotators by forcing the shoulder joint up while the elbow is bent with the forearm and racket at about a 90° angle and back a little from vertical. When the shoulder joint rises the the inertia of the forearm and racket causes the shoulder joint to externally rotate stretching the internal shoulder rotator muscles, mainly the pec and lat. You can see this stretching and how it is timed relative to the leg thrust in high speed videos. Watch for the upper arm rotation - that indicates internal or external rotation of the shoulder joint. https://vimeo.com/user6237669/videos

In addition to the leg thrust when the tossing shoulder is brought down and the hitting shoulder is rapidly raised while the trunk is rotated this also stretches the internal shoulder rotators (or maintains the stretch already there from the leg thrust). This motion is more complicated compared to the leg thrust's mostly causing the shoulder joint simply to rise. The leg thrust & trunk motions also overlap during the service motion.
Click to expand...

Thanks! Good explanation of the purpose of the knee bend / leg thrust. I was always confused about how the leg thrust is supposed to help on the serve (certainly not trying to do a volleyball-style jump serve), so I've always struggled with proper leg involvement on the serve. I'll try to feel the leg push help stretch my shoulder rotation... stretching my internal shoulder rotator muscles due to external shoulder rotation caused by leg thrust? Hope I got that right.
 
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Chas Tennis

G.O.A.T.
Things get a little tricky here unless you look at how the muscles are attached and work in a reference.

The big back muscle that is used for the pull up, the lat, is attached to the front of the arm near where the pec is attached. When the arm and scapula (shoulder blade) are held up as in all high level serving and these muscles are stretched then, if the arm is held stationary so that it can only rotate, these muscles can rotated the arm very,very rapidly. That shoulder joint motion is internal shoulder rotation.

Illustrations - lat attachment on the front of the arm.
https://www.google.com/search?q=ill...ng.com%2Flatissimus-dorsi-muscle.html;299;576

(CF and others still believe it is best to keep using the term 'pronation' incorrectly instead of ISR. ??)
 
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Chas Tennis

G.O.A.T.
Early History - Internal Shoulder Rotation

SystemicAnalomy, Thanks for this very interesting historic information

SystemicAnomaly said:
^ Don't know about early studies of ISR. However, the earliest mention of pronation in badminton strokes that I've seen came from Dr James Poole in
a paper from the 1960s. Poole was a world class badminton player from the US from the late 1940s thru the 1960s, I believe. He also played tennis and other sports at a high level.

His paper on pronation may have been his PhD thesis in the 1960s. This was something of a radical notion since everyone else perceived badminton as a wristy sport. He claimed that the role of the wrist was grossly exaggerated and pronation actually played a more important role.

This paper was written some 2 or 3 decades before tennis and badminton coaches started the acknowledge the role of forearm rotations in these sports. I recall seeing Poole's paper on the Internet more than a decade ago. Don't know if it is still accessible.
.
Click to expand...

Badminton!!??

http://www.guinnessworldrecords.com/media/6202230/Fastest-Hits-V2.jpg

Fastest-Hits-V2.jpg
 
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counterfeit25

Rookie
Chas Tennis said:
Things get a little tricky here unless you look at how the muscles are attached and work in a reference.

The big back muscle that is used for the pull up, the lat, is attached to the front of the arm near where the pec is attached. When the arm and scapula (shoulder blade) are held up as in all high level serving and these muscles are stretched then, if the arm is held stationary so that it can only rotate, these muscles can rotated the arm very,very rapidly. That shoulder joint motion is internal shoulder rotation.

(CF and others still believe it is best to keep using the term 'pronation' incorrectly instead of ISR. ??)
Click to expand...

The internal shoulder rotation happens after the external shoulder rotation, is that right? So:

1) The leg thrust causes external shoulder rotation of hitting shoulder
2) Internal shoulder rotator muscles are stretched due to external shoulder rotation
3) Internal shoulder rotation happens, and benefits from "stretch shortening cycle" (??) due to stretched internal shoulder rotator muscles from (2)
 
C

Chas Tennis

G.O.A.T.
counterfeit25 said:
The internal shoulder rotation happens after the external shoulder rotation, is that right? So:

1) The leg thrust causes external shoulder rotation of hitting shoulder
2) Internal shoulder rotator muscles are stretched due to external shoulder rotation
3) Internal shoulder rotation happens, and benefits from "stretch shortening cycle" (??) due to stretched internal shoulder rotator muscles from (2)
Click to expand...

That's right - but it's not only leg thrust. I'm not clear on the relative contribution of the trunk and shoulder low-to-high motions and possibly other motions. But if you can hit a heavy pace serve while on your knees these trunk contributions to racket head speed -with no leg thrust - are not necessarily small. Various servers might be using different contributions from the leg thrust and trunk motions or other motions.

It helps to know the proper names for the joint motions. Also, keep in mind those few muscles that shorten rapidly to supply force for racket head speed leading to impact.
 
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counterfeit25

Rookie
Thanks Chas. My main confusion was how the leg drive contributes to the serve, but I agree there are many other motions involved.

A little off topic, but I serve an alright pace serve with less than 10 degree knee bend =\ It usually clocks around 100-105 mph, using my Tracer SRA3000. I'm sure there are technique improvements to be made in my trunk and upper body motion, but I think getting my legs involved will give the highest ROI at this point.
 
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Chas Tennis

G.O.A.T.
He is using ISR but does not identify it as such. In the video when he is hitting the net he has his elbow slightly bent. When he does ISR it rotates the upper arm and that slaps the forearm/racket into the net because of the small angle at the elbow.

On a pro serve the arm is about straight and the racket is held at an angle to the arm for acceleration and at impact. That angle changes from 80-90° just after the arm is up and straight to, say, 20-40°, at impact. The angles at impact varies especially with the type of serve. See high speed videos taken from behind. (Discussed in other threads. Search Toly + 2010, etc..)

If the elbow is straight then both pronation and ISR will produce the same rotation at the wrist. How can you tell which is rotating the wrist? Pronation involves the twisting of the forearm only - between the elbow and wrist. ISR involves the rotation of upper arm (Humerus) only - you can see this by looking at the axial rotation of the arm as indicated by the shadows of the elbow bones. You can see these elbow bone shadows in most of my Vimeo serve videos.

Jim McClellan has many excellent tennis videos but like virtually all tennis instructional videos of the recent past they could be updated to include the proper term and its role in the serve - internal shoulder rotation.
http://www.youtube.com/watch?v=0LyGN5YSuCY

Similar FYB video that could be updated to point out the part played by ISR.
http://www.youtube.com/watch?v=Y1C6V_3s4nA
 
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V

VeeSe

Rookie
dominikk1985 said:
the revolutionarytennis guy said that you can bend the knees too much when you are just bending and not bowing your front hip into the field.

hw said the bow is more important than the bend and the bend is assisting the bow. there has to be a balance.
http://www.revolutionarytennis.com/step12_2.html
Click to expand...

This is spot on with what I'm missing. It's impossible to get much of a bow with how low I'm getting with my knee bend, so I need to dial it back and work on getting a nice bow with my knee bend in a nice, smooth motion.
 
GoudX

GoudX

Professional
Roddick said it adds about 40mph to his serve, so that is roughly 1/3rd of the speed. Which means that the majority comes from the upper body, but a fairly sizeable amount of speed can come from a good leg drive.
 
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Chas Tennis

G.O.A.T.
Todd Ellenbecker Video on Shoulder Anatomy, Injury Risk on the Serve

There are safety concerns with serving technique. Be sure to view the detailed Todd Ellenbecker video and especially understand the advice at about minute 8 for minimizing shoulder impingement risk.

Chas Tennis said:
I believe that serving with ISR is never forced and could cause injury if practiced incorrectly. Here are some known issues. With forceful and rapid ISR the small external shoulder rotator cuff muscles have to be conditioned to keep the ball of the humerus in place and to stop the arm rotation in the follow through. See recommended shoulder conditioning exercises. Easy, light exercises.

There are also the important safety issues related to technique such as the shoulder high orientation for the serve to minimize impingement risk. Just one very bad motion can cause injury.

1) Jim McLennan short video on the rotator cuff, impingement and serving
http://www.youtube.com/watch?v=lTRvxaBMh8s

2) Todd Ellenbecker video on shoulder anatomy, impingement, and serving. At about minute 8 he describes the same issue as McLennan but in more detail.
http://www.tennisresources.com/index.cfm?area=video_detail&vidid=3712&ATT=&reso=lo

If you are concerned because you are having pain, how can you determine that the technique that you use is OK? You have to study and know the proper technique and verify that you are doing it with high speed video or find a well qualified instructor. Keep in mind that the more rapid motions during the serve cannot be seen by eye or even 60 fps video so an instructor who uses HSV is a plus.
Click to expand...

Chas Tennis said:
1) Safety First -


2) A reference for tennis targeted fitness, especially shoulder conditioning, is Complete Conditioning for Tennis by Roetert & Ellenbecker - http://www.tennis-warehouse.com/Complete_Conditioning_Tennis_Book__DVD/descpageKINETIC-BCCDVD.html

3) Study what internal shoulder rotation is on the serve. Search this forum for - internal shoulder rotation + serve
http://tt.tennis-warehouse.com/search.php?searchid=15166947
Most of my serve videos clearly show ISR - https://vimeo.com/user6237669

4) Consider high speed video to observe what your daughter is actually doing on her serves.

Recommend the book by Elliott and others which has progression information & milestones for different age groups, Technique Development in Tennis Stroke Production (2009) - https://store.itftennis.com/product.asp?pid=86&bid=4&previousscript=/brand.asp
However, the chapter on backhands is not good and my copy has many errors in that one chapter, especially with the figure captions. ??
Click to expand...
 
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Raul_SJ

Raul_SJ

G.O.A.T.
GoudX said:
Roddick said it adds about 40mph to his serve, so that is roughly 1/3rd of the speed. Which means that the majority comes from the upper body, but a fairly sizeable amount of speed can come from a good leg drive.
Click to expand...

Roddick and Dent both hit huge (~145 mph) serves.

Dent is saying that his leg drive contributes marginally while Roddick says it adds 40mph.

That raises the question of whether Dent is under-utilizing his legs and capable of hitting a much faster serve?...

But somehow I doubt that it is the case. Weren't pros like Laver hitting 130mph serves before the rule change that allowed lifting off the ground?

I think 145 mph is about the maximum potential of both Dent and Roddick ... Roddick is simply over-estimating the leg drive contribution.

I would estimate the Roddick's leg drive contribution to be ~10%-12% (15 mph rather than 40mph).
 
Raul_SJ

Raul_SJ

G.O.A.T.
Chas Tennis said:
He is using ISR but does not identify it as such. In the video when he is hitting the net he has his elbow slightly bent. When he does ISR it rotates the upper arm and that slaps the forearm/racket into the net because of the small angle at the elbow.
Click to expand...

Is there a source that describes all the elements of the kinetic chain on the serve?

I think I have identified the end parts of the chain as:

Internal Shoulder Rotation --> Forearm Roll/Pronation --> Wrist Snap
 
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Chas Tennis

G.O.A.T.
Raul_SJ said:
Is there a source that describes all the elements of the kinetic chain on the serve?

I think I have identified the end parts of the chain as:

Internal Shoulder Rotation --> Forearm Roll/Pronation --> Wrist Snap
Click to expand...

I would not see

"Internal Shoulder Rotation --> Forearm Roll/Pronation --> Wrist Snap" as a sequence of one leading to another - IRS is there throughout. I have trouble seeing pronation in high speed videos. ISR is obvious. Look at videos and identify what you mean by 'wrist snap'. Where is the 'wrist snap'? https://vimeo.com/65434652

Speculation - I believe that IRS rotates the arm causing the wrist to move as the arm-racket angle changes and the racket spirals up to impact. It goes from racket 'edge-on' to strings facing the ball mostly because of the rotation of ISR. See the above video. The arm rotates and this allows the wrist to continue on into the follow through with passive wrist joint motions. Do any wrist joint muscles drive a 'wrist snap'? I believe that the ISR gets things moving and the wrist just follows along without much muscle force from wrist flexors. Too complicated to understand very well though.

References-

Macci short video, kinetic chain.
http://www.tennisresources.com/index.cfm?area=video_detail&rv=1&vidid=2278

See article, T. Ellenbecker pages 1 & 4-9. See the graph of the kinetic chain sequence of body motions (pg. 4) & look for it in other references.
http://www.revolutionarytennis.com/Rev Tennis/download/usta-high-performance-vol-8-no-2.pdf

Kinetic Energy Transfer During the Tennis Serve. 2009 Cristina López de Subijana, Enrique Navarro
http://www.jhse.ua.es/jhse/article/view/38/142

Biomechanics and Tennis (2006) B. Elliott – A short summary paper outlining the main ideas.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2577481/

Well chosen comments on learning tennis strokes. B. Elliott
http://www.itfcoachesconference.com/2009/user/24

There are several articles on tennis, the kinetic energy chain, etc. by coachesinfo.com. For example,
http://coachesinfo.com/index.php?op...e&catid=95:tennis-general-articles&Itemid=173

ITF Coaches Presentation – Biomechanical Principles for the Serve in Tennis, SSC & Phases of the Serve, etc. However, I disagree on time presented for stretched muscle to lose potential to supply stretch force – the stated “1 second” is too long in my opinion.
http://www.itftennis.com/shared/medialibrary/pdf/original/io_24976_original.pdf

ITF Presentation - Power and the Tennis Serve (dated?)
http://www.itftennis.com/media/114010/114010.pdf

ITF Presentation - Biomechanics of Tennis: An Introduction (2007)
http://www.itftennis.com/media/113862/113862.pdf

ITF Presentation – Biomechanics of the Tennis Serve, (2007) B. Elliott
http://www.itftennis.com/shared/medialibrary/pdf/original/IO_24973_original.PDF

Technique effects on upper limb loading in the tennis serve, (2003) B. Elliott, G. Fleisig, R. Nicholls & R. Escamilia
http://biomechanics.stanford.edu/me337/projects/elliot03.pdf

This pdf does not open to display correctly for me. Browser suggests a different viewer and when I select Adobe (default) it works fine. If anyone has a better direct link please supply. Or, double click on it in your list of downloads?
Contributions of Upper Limb Segment Rotations During the Power Serve in Tennis(1995). Bruce C. Elliott, Robert N. Marshall, and Guillermo J. Noffal - Was this the first ISR paper for the tennis serve?
http://www.exeter.ac.uk/media/unive...alexeter/documents/iss/Elliot_et_al__1995.pdf

Long-axis rotation: The missing link in proximal-to-distal segmental sequencing (2000) Marshall & Elliott, not available free, (translation - Long axis rotation - arm rotation from ISR; proximal - close & slower, as the leg or trunk; distal - more distant and much faster, occurs later in the motion, the arm & wrist. Basic kinetic energy chain.
http://www.tandfonline.com/doi/abs/10.1080/026404100364983#preview

Bruce Elliott publications
https://www.socrates.uwa.edu.au/Staff/StaffProfile.aspx?Person=BruceElliott&tab=publications
 
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tennisdad65

Hall of Fame
Raul_SJ said:
Dent is saying that his leg drive contributes marginally while Roddick says it adds 40mph..
Click to expand...

That's because they have completely different serving techniques.
Roddick does depend on knee bend a lot with almost no back arch.
Dent used more back arch (not recommended these days). I have seen quite a few old timers using back arch for kick serves. Knee bend is better.

Anyways, Dent ended up having major back problems. Roddick with shoulder issues. I would not copy either of their motions.
 
Lukhas

Lukhas

Legend
^Then kick serving like Rafter always did is also forbidden? As well as Sampras' serve, who had chronic shoulder tendinitis. We also should avoid using Federer's motion since he has recurrent back problems? Nor Gasquet's BH since he had tennis elbow with it?

The tour isn't soft on the body. Not a lot of sports are. It's not surprising a sizeable amount of pros retire after injuries or worn out body. Continuously hitting the same strokes wears the body out, until it says "Stop". And that's not always a technique issue.
 
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Chas Tennis

G.O.A.T.
Leg Thrust and/or Trunk Motions for Stretch

As tennisdad65 says, possibly Dent and Roddick use different amounts of leg thrust and trunk/shoulder motions (shoulder low to shoulder high plus trunk rotation) to stretch their internal shoulder rotators.

Probably both the leg thrust or trunk motion can be used for ISR stretching (as serving while on the knees shows). The lat & pec can only be stretched so far.

A second interesting question is: Once the lat is stretched by leg thrust, does it get farther stretched or is the stretch maintained by the shoulder low to shoulder high trunk motions?

The reference, Manual of Structural Kinesiology, specifically mentions a very interesting point on the trunk motions and their effect on farther stretching of the lat. Here is an earlier thread that discusses this point.

Chas Tennis said:
Background - My interpretation of some biomechanical research results on the serve-

During the service motion, first, the tossing shoulder is up and the hitting shoulder is down. Then the hitting shoulder is very rapidly moved high using trunk lateral flexion. Last, the final racket head speed is increased to ball impact using mostly internal shoulder rotation. Internal shoulder rotation contributes the most to racket head speed.

The internal shoulder rotators are pre-stretched by the leg thrust. The stretch occurs because the upper arm is at about 90° to the body and the racket and forearm are at about 90° to the upper arm when the legs thrust up and carry along the shoulder. This externally rotates the shoulder stretching the internal shoulder rotator muscles. The internal shoulder rotator muscles are the lat (Latissimus Dorsi), pec (Pectoralis Major), Teres Major and some others. The largest muscle connected to the arm is the lat, the second largest is the pec. Both insert on the front of the upper arm at the same location and internally rotate the shoulder by pulling on the humerus at that insertion point.

The question is what part does raising the hitting shoulder play in farther stretching the lat or in maintaining the stretch?

Apparently it is well known that raising the shoulder can increase the lat stretch.

From the Manual of Structural Kinesiology, C. Thompson, R. Floyd, 15th ed., page 89:

paraphrasing

The stretch (of the lat) may be increased ................by then laterally flexing and rotating the trunk to the opposite side.

(This is a great basic reference. It is a popular college text and the latest edition is $75 while the recent editions like the 15th are just $10 or so.)

Lateral trunk flexion is just the side bend that puts the hitting shoulder up. Rotation of the trunk is just the trunk turn that is used for serving. Both of these lat stretches can easily be felt by just holding the upper arm at 90° to the body and rotating the forearm up and back as in the service motion to give the internal rotators some stretch. When stretched in that way, laterally(side) bend the trunk, feel the lat stretch. Also rotate the trunk and feel the lat stretch.

In Knudson's book, Biomechanical Principles of Tennis Technique, I think he discusses the speed of stretched muscles as more rapid.

Does this late trunk flexion and rotation play an important part for the serve by final stretching of the lat for added racket head speed?
Click to expand...

The trunk motions are complex so see high speed videos.
 
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BaselineB

BaselineB

New User
Chas Tennis said:
As tennisdad65 says, possibly Dent and Roddick use different amounts of leg thrust and trunk/shoulder motions (shoulder low to shoulder high plus trunk rotation) to stretch their internal shoulder rotators.

Probably both the leg thrust or trunk motion can be used for ISR stretching (as serving while on the knees shows). The lat & pec can only be stretched so far.

A second interesting question is: Once the lat is stretched by leg thrust, does it get farther stretched or is the stretch maintained by the shoulder low to shoulder high trunk motions?

The reference, Manual of Structural Kinesiology, specifically mentions a very interesting point on the trunk motions and their effect on farther stretching of the lat. Here is an earlier thread that discusses this point.



The trunk motions are complex so see high speed videos.
Click to expand...

Great post(s) Chas Tennis!

I feel that the stretched muscles provide a structural rigidity that we use to get more of the body's energy into the ball.
 
DirtBaller4

DirtBaller4

Rookie
I notice my serves start going long when my knees get tired and don't bend enough, so i think I get mostly a bump in spin from my knee bend.
 
Raul_SJ

Raul_SJ

G.O.A.T.
Coach Jeff Salzenstein talks about getting the elbow out of line with the body at the trophy position:

http://www.youtube.com/watch?feature=player_detailpage&v=PGWyLmyWzvc#t=58s

Is this movement the same as external shoulder rotation?

I feel a sensation in the chest muscles and shoulder blades when I move the elbow away from the body.

I never had that sensation before and now my serve seems to have more power...

But not sure if I am overdoing it because I feel the shoulder blades pinch together.
 
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Chas Tennis

G.O.A.T.
Raul_SJ said:
Coach Jeff Salzenstein talks about getting the elbow out of line with the body at the trophy position:

http://www.youtube.com/watch?feature=player_detailpage&v=PGWyLmyWzvc#t=58s

Is this movement the same as external shoulder rotation?

I feel a sensation in the chest muscles and shoulder blades when I move the elbow away from the body.

I never had that sensation before and now my serve seems to have more power...

But not sure if I am overdoing it because I feel the shoulder blades pinch together.
Click to expand...

Elbow out - is an undefined term. It is shown, I guess, in the video. ? No reason is given for why it is to be held in that way. ?

The Ellenbecker video discusses the same thing but gives the rationale for the arm position - the upper arm (humerus) should be a certain alignment to the shoulder joint so that external rotation and internal rotation are less likely to cause impingement. See the video.

If you stretch the internal rotator muscles by external rotation of the shoulder joint and these stretched muscles contribute, they can shorten fast. You also do not have to deliberately activate - send nerve signals to - stretched muscles for them to shorten. It can feel as if you are not doing much - as a Bryan brother has said about tennis strokes 'it's free energy'.

There is no reason to pinch your shoulder blades together that I can think of. ?

Take a video to see what you are doing.
 
Raul_SJ

Raul_SJ

G.O.A.T.
Elbow out - is an undefined term. It is shown, I guess, in the video. ? No reason is given for why it is to be held in that way. ?

Jeff Salzenstein didn't get into the technical explanation but the elbow at the trophy pose should not be inline with the body -- it's like you are "elbowing the enemy" standing behind you.

I believe my elbow was inline with the body with my previous motion.

Now, when I "elbow the enemy", I feel a stretch in the chest muscles and some sensation in the right shoulder blade-- seems like energy is being stored and then later released -- resulting in a powerful serve.

Jeff says he has gotten instant results with students on this tip and it seems to work for me, (although I have just begun to try it out.)

Haven't checked the Ellenbecker video yet but it seems like he also supports the same "elbow the enemy" position in the Jeff Salzenstein video ?
 
C

Chas Tennis

G.O.A.T.
Raul_SJ said:
Elbow out - is an undefined term. It is shown, I guess, in the video. ? No reason is given for why it is to be held in that way. ?

Jeff Salzenstein didn't get into the technical explanation but the elbow at the trophy pose should not be inline with the body -- it's like you are "elbowing the enemy" standing behind you.

I believe my elbow was inline with the body with my previous motion.

Now, when I "elbow the enemy", I feel a stretch in the chest muscles and some sensation in the right shoulder blade-- seems like energy is being stored and then later released -- resulting in a powerful serve.

Jeff says he has gotten instant results with students on this tip and it seems to work for me, (although I have just begun to try it out.)

Haven't checked the Ellenbecker video yet but it seems like he also supports the same "elbow the enemy" position in the Jeff Salzenstein video ?
Click to expand...

In most high speed videos it might be difficult to see how the upper arm aligns with the plane(?) of the body. I think that these serve views from above show the upper arm-body alignment.

(You can often do stop-action single-frame on Youtube videos by using the arrow keys to advance or go back one frame.)

FYB Flat serve from Above
http://www.youtube.com/watch?v=4a9X_eTdg8I

FYB Kick Serve from Above
http://www.youtube.com/watch?v=2FpeYGG9XAg

FYB Slice Serve from Above
http://www.youtube.com/watch?v=IMgQWotcPYE

Raonic serve
https://vimeo.com/63688134

Federer serve
https://vimeo.com/63688132

I don't see the elbow back relative to the body.
 
Last edited:
Lukhas

Lukhas

Legend
By "elbow the enemy", Jeff means that in your trophy pose, your elbow should be away from your body. Basically he often sees beginners having a shoulder almost stuck to the body in trophy pose. So he says "elbow the enemy" to get it out of the way. The same way, Federer says "keep your elbow high". Which basically means the same thing: elbow out of the body in trophy pose.
 
C

Chas Tennis

G.O.A.T.
Lukhas said:
By "elbow the enemy", Jeff means that in your trophy pose, your elbow should be away from your body. Basically he often sees beginners having a shoulder almost stuck to the body in trophy pose. So he says "elbow the enemy" to get it out of the way. The same way, Federer says "keep your elbow high". Which basically means the same thing: elbow out of the body in trophy pose.
Click to expand...

What is meant is not that clear at 2:08 in the video.
 
Lukhas

Lukhas

Legend
For me it is perfectly clear. When his student/helper displays his trophy pose, Jeff comments on the elbow high and away from the body like you're elbowing an enemy that stands behind you. I hope I was able to explain to you what he meant.
 
B

boramiNYC

Hall of Fame
VeeSe said:
This is spot on with what I'm missing. It's impossible to get much of a bow with how low I'm getting with my knee bend, so I need to dial it back and work on getting a nice bow with my knee bend in a nice, smooth motion.
Click to expand...

you are on the right track I believe. practice serving with minimally bent knees like wawrinka or even less. or it could be your front side of the pelvis is not very flexible and just cannot stretched to make the bow. try some stretches for your psoas muscles.
 
dlam

dlam

Semi-Pro
Great thread lots of advice from the pros who can serve
The clock picture is something that I use too to visualize the spin I get on the ball on the serve
When I'm serving well I actually don't see the "whole ball" I see the ball as an eclipse like crescent shape moon
 
J

Jkramer

New User
VeeSe said:
where my knee is 4-5 inches from the ground (that's where all the power came from). .
Click to expand...

4" from ground!!! I love to see a photo. I assume you're not small people. The knee bent at 90 deg or less? Your knees won't last long at this bend. Even Sampras has very low bent knee, it still must higher than 12". Bending the knee at this acute angle will not allow the leg drive to accelerate fast, or you must be very light weight. Study the pro serve video, and change yours to save the legs.
 
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