Spine Extension Profile?

[natep]

There's been a lot of good 3d data around here lately.

I'm curious, do any of the 3d machines measure spine extension?

Are there any acceleration profiles out there?

I'm curious to know whats going on with extension leading up to and during impact.

Does it slow down and stabilize through impact? Or is there constant extension through the ball?

If there is extension through impact, is it decelerating or accelerating?