I don't remember saying Tiger was doing it conciously....
And how can you say that it is not an active force? If his legs are pushing it is an active force, concious or not.
Hiya Puttmad,
Didn't mean to imply that you said something you didn't.....sorry 'bout that.
As I see it, the body is a support mechanism that the forces during a golf swing push against, which in turn push against the earth. I see the knees more as shock absorbers to accommodate the downward blow to the ball. By squating I feel he is just lowering his center of gravity preparing the body for all that force. This position also makes the angles in the legs and back more accute, giving them more stability. Something stronger to push against.
If he were to push with his legs I don't think he would reach low point very often (j/k).
So, it seems to me that when he is applying force to the shaft in the downswing that force is really being pushed against the structure of his body and the earth. The look of push up in the legs is only a reaction to the full extention deep into low point.
As an experiment, take a basketball in both hands and throw it straight down as hard as you can, with full extension of your hands and arms. Chances are you will come up on your toes. What caused that to happen? An even more amazing reaction is to see how far you can uncock your wrists (no club) in front of you. The farther you go the more your heels will lift off the ground. Weird but true.
Not very scientific..........I need a bigger vocabulary