Low posture before receiving

I was watching some people play the other day, and also while watching pros on TV especially such as ZJK i notice when the opponent is preparing to serve (but has not yet swing their arm to serve the ball yet) they get down very low, and get their upper body and eye level almost at the table height.

such as this guy here: http://imgur.com/a/gLgBn

And i noticed they only do that for the very short interval before the opponent begins the serves, and immediately once the opponent starts the swing the receiver will move back to the ready stance.

thanks pingskills!

Hi Aaron,

This gives them the bailey to move quickly from the lower base position.  It engages the muscles in their legs which help with the movement.