Your body weight into the ball?

Many times you have probably heard about the importance to transfer your body weight into the ball. IT IS MISSION IMPOSSIBLE!!! Actually playing tennis you can only strike a ball. The contact time between strings and balls lasts only from 3 to 5 milliseconds the time of photo flash.

Strike a ball is an action which has nothing to do with pushing nor throwing even though the biomechanics of the movement looks similar.