When rotation starts?

[ralph]

Just need confirmation about when the windshield wiping rotation should begin, prior to contact or at contact. I would guess at contact, or does an earlier start build up a quicker rotation through the ball?

Ralph

[jlkm2219]

Just need confirmation about when the windshield wiping rotation should begin, prior to contact or at contact. I would guess at contact, or does an earlier start build up a quicker rotation through the ball?

Ralph

Watching players with heavy topspin (Nadal, Moya, Verdasco, Roddick) seems to me that the windshield wiping begins prior the contact. I've tried myself and I've found that timing wold be perfect in order to control the direction of the stroke.

[John Yandell]

I think you feel it as starting just before--it's very difficult to see in even the high speed footage.