internal shoulder rotation on serve

[taurussable]

In the internal shoulder rotation demonstration above , the man's upper arm is close to his body.

in serve contact, the arm is above the head.

How is ISR motion related to the serve considering the position of arm is completely different from the first and second picture?

Also are there videos explaining ISR in the serve? got a hard time understanding text alone..

 

[taurussable]

found this also

Is above correct demonstration of ISR or below?

 

[suryanaga]

They are all examples of internal shoulder rotation. Try the bottom example in post 2 and then raise your arm above your head and perform the same exact rotation. Same movement but your arm is in a different position. The wrist pronation at the point of contact of a serve is a form of internal shoulder rotation.

 

[taurussable]

Thanks, it make sense now.

I appears to me that the "high elbow" finish is natural result of ISR: elbow joint fixed and rotate forearm inward/downward--exactly what was demonstrated in both pictures.

 

[Chas Tennis]

Todd Ellenbecker Video on Shoulder Anatomy, Injury Risk on the Serve

Videos that discuss the shoulder, impingement and the shoulder orientation to minimize the risk of impingement on 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.

 

[Chas Tennis]

Demonstration of Pronation & ISR + ISR in Videos

1. Pronation. Stand with the arm elbow at your side and with a 90° bend in your elbow. Rotate the forearm back & forth to pronate and supinate the elbow joint - pronation twists the forearm rotating the wrist.

2. Internal Shoulder Rotation. Raise a straight arm so that it is 90° straight out from the shoulder. Now rotate only the upper arm around its axis. It rotates the entire arm and wrist. When the upper arm axially rotates at the shoulder it is internal shoulder rotation or external shoulder rotation. ISR & ESR can be done no matter where the arm points.

With the arm still straight out, try doing upper arm ISR and forearm pronation separately.
Notice that whenever the arm is straight both pronation and internal shoulder rotation have exactly the same effect of rotating the wrist. In tennis discussions of the serve, there is confusion between the terms 'pronation' and 'internal shoulder rotation'.

Pronation & ISR are independent joint motions that add together to give wrist rotation. On the serve the ISR is what dominantly rotates the wrist accelerating the racket to impact.

Do you see the general line between the two shoulders and the line of the upper arm bone (humerus) in this Venus Williams serve? All pro serves have that high-low shoulder orientation - shoulders tend to be somewhat in line with the upper arm. The Ellenbecker video describes the shoulder and how that shoulder orientation minimizes the risk of impingement.

The ISR lasts only about 1/4 second around impact in this pro high speed video - look only at the elbow bones - can you see it?

https://vimeo.com/27528701

Search the many threads here with discussions of ISR and the serve.

Search Internet- internal shoulder rotation tennis serve pictures

 

[Chas Tennis]

Videoing Internal Shoulder Rotation on Your Serve

You are already using ISR in your serve. Take a video of your serve wearing a sleeveless shirt to see the upper arm, place a marker on your upper arm.

https://vimeo.com/21512296

Very puny ISR.

 

[5263]

Excellent example with Venus as she appears to OVER do it slightly, but it
makes for a good illustration of the idea.

 

[Chas Tennis]

There are some variations in the angle - up to a limit.

You are right about Venus on that particular picture. She does have one of the best WTA serving techniques.

Check out the angles on many pros and some amateurs by Searching: internal shoulder rotation tennis serve picture
https://www.google.com/search?q=int...uIGQCg&ved=0CDoQsAQ&biw=1006&bih=606&dpr=1.25

In this frame from a video, Federer seems to have more of an angle with shoulders less vertical. Camera viewing angle might make some difference also. ??

WORSE CASE WITH SHOULDERS LEVEL _

Compare to this worse case shoulder orientation. If you do ISR with this level shoulder orientation according to Ellenbecker your risk of impingement increases - see his video.

I see considerable variations of this shoulder orientation on the rec and club tennis courts. Some make me cringe.

 

[taurussable]

Notice that whenever the arm is straight both pronation and internal shoulder rotation have exactly the same effect of rotating the wrist. In tennis discussions of the serve, there is confusion between the terms 'pronation' and 'internal shoulder rotation'.

Pronation & ISR are independent joint motions that add together to give wrist rotation.

when the elbow is straight, I feel it is not as easy to separate the ISR and pronation. awesome explanation btw.

 

[LeeD]

But the elbow isn't straight on any stroke.
Not even on a "straight arm" groundie. There is a little natural relaxed bend.
And on a serve, where we should be focused, the trophy position has the elbow BENT at 90 degrees or more.

 

[taurussable]

the trophy position has the elbow BENT at 90 degrees or more.

agree, good servers do. I need fix my trophy.

what i meant is:
when my elbow is straight and I rotate my arm on its axis I can't even tell if I am doing forearm pronation or ISR.