How to fix my knees (serve) and get more power

[donquijote]

I have a psychological prohibition while serving. I can't get the power from my knees because I can't spring them enough. I believe the reason is the prohibition in my subconscious that if I bend my knees down then I have to lower my body and my contact with the racquet to the ball will be lower in the air and hence reducing my chances to get the ball over the net. I hope you understand what I mean.

How can I overcome this fear? As I said it is not conscious but I think it is there. Thanks.

 

[Topspin Shot]

Almost certainly not psychological but technique-related.

 

[LeeD]

How about......?
If you're going to jump up to reach something, would you bend your knees and lower your body?

 

[watungga]

It is psychological on your part.

There is only a miniscular height in terms of:

1. Standing flat footed on ground, and;
2. Knees are bent but feet on tip-toe on ground (first frame)..

Think of #1 as the same level as standing on ground, you'll do fine.

 

[Chas Tennis]

The knee bend has an important function on the internal shoulder rotation serve - to produce external shoulder rotation and pre-stretch the internal shoulder rotator muscles as described in many posts and a few well known reference books.
http://tt.tennis-warehouse.com/showthread.php?t=475036
For other serving techniques, knee bend may have little function except changing height. Little information is available for knee function for other unknown serving techniques.

First, take video of yourself and see what serving technique you are using. 30 fps is OK for this slow stuff such as the knee bend but you need a fast shutter to capture the racket position for the comparison below. It will likely take several 30 fps videos of serves to catch the racket in the 'edge-on' position with the elbow straight.

If your motion looks like Nalbandian's, the things that your read about knee bend for the high level serve apply to you.
http://www.hi-techtennis.com/serve/nalbandian_l.php
If your arm and racket positions don't look like this, maybe Waiter's Tray?, you are on your own....

It you have the idea that you should reach as high as possible, look carefully from side and behind camera viewpoints at high level servers at impact. They are not reaching as high as possible because there are trunk, arm and racket angles that are not straight up.

 

[donquijote]

It is psychological on your part.

There is only a miniscular height in terms of:

1. Standing flat footed on ground, and;
2. Knees are bent but feet on tip-toe on ground (first frame)..

Think of #1 as the same level as standing on ground, you'll do fine.

So if I weigh on my toes, then will it be sort of automatically fixed? I can keep telling myself 'on your toes! on your toes!' before I serve each time.

 

[donquijote]

The knee bend has an important function on the internal shoulder rotation serve - to produce external shoulder rotation and pre-stretch the internal shoulder rotator muscles as described in many posts and a few well known reference books.
http://tt.tennis-warehouse.com/showthread.php?t=475036

Funny you mention of shoulder rotation linking to bending knees cause I recently had some problems with my serving shoulder. I am aware that I don't rotate it as much as I should. The pain went away after a few weeks but I was really worried.

 

[Chas Tennis]

Funny you mention of shoulder rotation linking to bending knees cause I recently had some problems with my serving shoulder. I am aware that I don't rotate it as much as I should. The pain went away after a few weeks but I was really worried.

Here is a known shoulder safety issue for the serve -

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.

The internal shoulder rotation discussed here is the defined joint motion where the upper arm bone, humerus, rotates around its axis in the shoulder socket. The shoulder joint is named the "glenohumeral joint".

Some people may speak of 'shoulder rotation' and have a different motion in mind because they see the shoulders' moving. The upper arm bone rotates but the shoulder doesn't move from 'internal shoulder rotation'. Everybody missed this rotation for decades, until the mid Nineties!

See the Jim McLennan video first.

Many of these videos show ISR but it lasts only 1/4 second as played back. Watch carefully the shadows at the elbow bones.
https://vimeo.com/user6237669/videos

Stop experimenting with serving techniques if you have any shoulder pain.

 

[Raul_SJ]

Some people may speak of 'shoulder rotation' and have a different motion in mind because they see the shoulders' moving. The upper arm bone rotates but the shoulder doesn't move from 'internal shoulder rotation'. Everybody missed this rotation for decades, until the mid Nineties!

Not clear on the above.

I thought the Internal Shoulder Rotation is what causes the humerus bone to rotate.

 

[Chas Tennis]

Not clear on the above.

I thought the Internal Shoulder Rotation is what causes the humerus bone to rotate.

Let's try another word - replace 'move' with 'translate' -

.....the shoulder does not translate from internal shoulder rotation, as an electric motor does not translate when its shaft is rotating.

 

[boramiNYC]

Let's try another word - replace 'move' with 'translate' -

.....the shoulder does not translate from internal shoulder rotation, as an electric motor does not translate when its shaft is rotating.

The shoulder must move very specifically along the ISR or esr for them to rotate in full ROM. For ISR the shoulder needs to be elevated and protracted. If the shoulder ROM is limited the rotation will be limited.

Further, the shoulder moves in coordination with T spine. So a mobility problem at T spine could affect shoulder mobility and even the arm rotations.

Between T spine, shoulder, and arm there are a lot of coordination problems as well.

 

[julian]

Please see the thread "A Perspective on Plyometrics in Tennis by Jez Green"

Let's try another word - replace 'move' with 'translate' -

.....the shoulder does not translate from internal shoulder rotation, as an electric motor does not translate when its shaft is rotating.

Please see the thread
"A Perspective on Plyometrics in Tennis by Jez Green" about something different.

 

[TennisCJC]

I would start by just thinking of a small flex like 2 or 3 inches. Trying to exaggerate the flex is likely to result in timing, rhythm and hitch issues.

You can also think of a slight bend in the knees but keeping the body from knees to head in a relatively straight line like the first photo in the sequence above - Federer and Cilic do this - bend at the knee but torso sort of lays back in a straight line with no or little back arch.

 

[watungga]

So if I weigh on my toes, then will it be sort of automatically fixed? I can keep telling myself 'on your toes! on your toes!' before I serve each time.

Post a video. We will have better analysis on your knee issues. There are body/mind factors that are intertwined that gives the natural tendency to jump.