body transfer

[berkeley03]

John,
Can you address the statement that the pro men transfer their body weight into the forehand? I hear coaches tell me that the pros are jumping into the forehand, that they're putting their body weight into the shot, etc. What is the science or biomechanics behind this assertion? Is it true? I see many clips of forehands where there looks to be little if any forward movement. I do see the coil and uncoil, but that often results to me in a rotation around rather then forward into the court. Thanks.

[johnyandell]

Remember I'm not a scientist (history major). So this is a layman's opinion. You hear people throw around the Force = Mass x Acceleration thing a lot and talk about body weight as the mass.

Actually the mass is the racket. It's all about the speed of the racket. The racket people can tell you that increasing the swing speed has a much bigger effect than increasing the mass--because you can't triple the weight of the racket.

So it may work as a metaphor. By coiling, uncoiling, jumping etc, you are generating energy FROM your body (which has a mass) but what that is really doing is causing the mass of the racket to (hopefully) move faster.