[bioengine]

Wish that V.J. Trolio was in on the discussion. He has
really made a study of the forward move which I call
the Hogan Move. One of the things that V.J. says
is as follows:

On the right leg,knee, etc...As mentioned in the book
the head will go down but not forward. This will
increase the left knee flex quite a bit at the top..
some 15 to 20 degrees. There are forces that must be
used by the pivot. One being longitudinal force into
the ground, the other sheer forces. As you turn and
move left, placing the center of mass over the left
leg, the head will go down, the left knee will increase
flex, and a force will be felt into the ground under the
left foot. This is the longitudianal force. Once this
force is in the ground (martial arts calls this rooting)
then the instep of the right foot and the larger muscles
of the left leg and glute are used to create sheer forces
(forces that run parrallel to the surface of the ground)
for extreme rotational ability. With that said, make
sure you feelthe downward rooting into the ground.

The new DVD by Trolio, showing concepts in the "The Final
Missing Piece" book is very good. About $20.00, not expensive.

dkerby,
Where do you think Trolio, got his information from. This isn't from his own research.
Although one miss guided information is the right foot and larger muscles of the left leg is what creates shear forces.
The shear forces aren't what create rotational talk. The center of mass moving along the target line pressing into to your left side and creating opposite ground reaction forces is what creates rotational torque. Continuing to press into your left side and creating ground reaction forces is what creates super stiffen or rooting.
A research paper on normal and shear forces was in a US golf magazine 18 years ago of the guy who discovered ground forces. These guys were one of the first to start golf research.

Ground forces are not only in golf they are applied in tennis baseball, any bat and ball sport, even the throwing action.
This is nothing new, ground forces has been around for a long time. Although it's only now that the golf industry is starting to implement golf biomechanics as part of teaching, now people are talking about ground reaction forces.

Again this is theory. We all know the theory, all that matters is how you train the body how to create ground forces. It's something you can physically apply in your swing.
Like geometry you have to train your geometry, same applies for ground forces you have to teach your body the right movement patterns to create ground forces.

I hope Trolio has the common decency to give the researchers where he sourced his information from a kick back on the videos he's cashing in on.