Originally Posted by dominikk1985
overturn is a signal for inefficient energy transfer. energy is transferred by stopping the earlier body parts in the kinetic chain.
that means the shoulders stop when the chest faces the net which causes the arm to whip through. the top players don't rotate with their shot but rotate early and delay their very fast arm strike till the very end.
Turn-Stop-Whip (but in one fluid motion which is the hard part
watch how early he rotates and how quiet his shoulders are at release
If you aren't slowing shoulder rotation just prior to contact you're losing a lot of power that could be delivered to the ball. The shoulders need to slow prior to contact in order to maximize arm and ultimately racket acceleration.
A back and core researcher (name escapes me at the moment) claims that professional athletes were good at very quickly stiffening the core to help other parts of the body accelerate.
Practice rapidly accelerating the shoulders but then trying to actively slow their turning when they are almost parallel to the net (assuming you're hitting down the middle).