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12-23-2013, 10:05 AM   #29
julian
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Join Date: Dec 2006
Location: Bedford,Massachusetts,US
Posts: 3,187
A peak of SSC

Quote:
 Originally Posted by Chas Tennis Ball contact or impact lasts about 3-5 milliseconds. A stretch shortening cycle for a joint motion may be much longer, a slower stretching phase followed by an accelerating phase, tenths of a second? Usually for impact those particular SSCs have reached a high velocity. (ISR for the serve.) If you mean the SSC or those SSCs that continue to impact, try to identify, by muscles or joint. For example only, Leading to impact, a SSC cycle of trunk muscles is used to rotate the upper body and a SSC of a shoulder muscle is used to accelerate the arm, etc.
Greetings,

I do NOT fully understand your post.
Let me try to get a bit closer and explain what I understand and what I do NOT.
I agree about 3-5 miliseconds and mechanics behind SSC.
Say that SSC for a FOREARM lasts 40 miliseconds
(so I responded to your request to specify "by muscles or joint").
It is MUCH shorter that you suggest.
So it is a first difference between two of us.

Let me check whether a classic paper by Komi provides any numbers.
I will get back to you on this one today or tomorrow.
The signal can be respresented either by a square or exponential function.
Say that it is an exponential function of TIME.
Let say SSC starts 20 miliseconds BEFORE the CONTACT with a ball.
The maximum COULD be around the CONTACT point with a ball.
Am I proceeding a REASONABLE direction so far?

I can justify 40 seconds in couple of hours-I am on a court right now.
Julian W.Mielniczuk
PhD.

Last edited by julian; 12-23-2013 at 10:24 AM.