This is almost a counter intuitive deal . . . . for the hands to stay on plane without a plane shift out . . . there HAS TO BE LATERAL MOVEMENT. Keep in mind the plane that a top spins on is a Horizontal Plane . . . . our basic plane is inclined . . . so for the hands to stay IN on the way down you have to tilt your axis . . . we're trying to move the hands in a circle . . . not necessarily the pivot. Lateral is a big deal interms of plane and circle.
Bucket, Im struggling with this one a little. The vertical vs inclined plane thing seems great, please elaborate.
Does this relate to CF throwing the hands to a position that is OUT irrespective of the inclined plane? Cool. Is this what you mean? The science behind the need for axis tilt, the on plane right shoulder and therefore the hands all from a lateral hip slide action?
You are correct that the TGM pivot axis (which is apparently a vertical line centralised between the feet while going through the base of the neck) is different to VJ's pivot axis. VJ has invented his own concept of a downswing pivot axis which is imprecisely defined. It starts at the left foot and goes up the left leg and then it is angled towards the center of the body. However, he states that the pivot axis changes constantly throughout the downswing and I don't think that he has precisely defined how it is angled at different time points during the downswing. He also states that the COG is near the navel. In his recommended backswing pivot action where the pelvis is shifted left-laterally in the late backswing, the pivot axis would then be very close to passing through his COG as it is situated at the end-backswing position. He believes that with the COG located near the pivot axis, that it allows a golfer to rotate more efficiently around his (idea of a) pivot axis without any need for a lateral pelvic shift in the early downswing. By contrast, Stuart Appleby would have to shift his pelvis left-laterally first in the early downswing (towards the left white line in those SA photos) before he could pivot in a rotational manner around this downswing pivot axis.
I personally have more sympathy for VJ's pivot axis idea (than the TGM vertical pivot axis idea) because i) at least he acknowledges that the downswing pivot axis is located somewhere near the left femoral neck, the pivot point for the pelvis rotation in the late downswing/followthrough - rather than being arbitrarily located centrally between the feet; and ii) because he thinks of the pivot axis as being angled from the left foot to the base of the neck (roughly related to the idea of secondary axis tilt) - rather than being vertical. I think that those two defining points make more sense from a biomechanical perspective, and I can relate to it better than TGM's vertical pivot axis centralised between the feet that goes vertically upwards to the base of the neck - creating a hypothetical tripod-shaped structure.
However, I cannot really relate to the idea of the torso being an unitary rotating cyllinder that rotates around that downswing pivot axis. I think of the "rightwards tilted spine and its angled relationship relative to the straight left leg" as being a braced skeletal structure (kept stationary by the stationary head) that provides structural support stability - so that the arms can swing efficiently and fluidly across the front of the rotating body after release of PA#4.
You are correct that the TGM pivot axis (which is apparently a vertical line centralised between the feet while going through the base of the neck) is different to VJ's pivot axis.
Jeff.
Hey Jeff
Actually what I said was vj's "axis of rotation", TGMs "pivot center".
TGM's "pivot center" as defined in the glossary is: "SOME POINT on the body kept stationary throughout the Stroke, to stabilize the motion". CAPS BY ME.
VJ's axis of rotation for full shots is around the left foot. I dont have my Vj book with me but the two seem not to be mutually exclusive. VJ , if memory serves me correctly advocates shifting the hips, axis tilt, to align COG with his "axis of rotation" all the while holding the "pivot center" in place to stabilize the motion.
I may be wrong but assuming the head is not the pivot center the heads weight will have to be counterbalanced to avoid a wobble about the axis of rotation. No?
OK, now for the incubator stuff: Is this counterbalancing sort of like a fly wheel? Is there is a mechanical advantage to the counterbalance? Like in Leonardo's Flywheel. Click on the link and watch it go with just a flick of the hand.
Jeff, perhaps your objection to the pivot center definition would change with MORE thought given to it not being the head but rather the base of the neck or somewhere there abouts? The head with all of its weight counter balancing the mass on the other side of the axis of rotation like in Leonardo's flywheel? Perhaps you could do a drawing? The head's weight is considerable and would take a substantial amount of body or hip to offset it. An optical illusion of sorts when trying to perceive a pivot center and axis of rotation.
Im obviously out on a incubatorial limb here. Heck, just grip it and rip it.
Bucket, Im struggling with this one a little. The vertical vs inclined plane thing seems great, please elaborate.
Does this relate to CF throwing the hands to a position that is OUT irrespective of the inclined plane? Cool. Is this what you mean? The science behind the need for axis tilt, the on plane right shoulder and therefore the hands all from a lateral hip slide action?
You're deep dude.
"I gots to know". (Dirty Harry)
OB
OK . . . . stick your arms out from your shoulders parallel to the ground . . . .
Now make your hands move parallel to the ground in a cicle by turning like you were a helicopter. . . . your spine is ONLY required to twist to keep them on that horizontal plane . . .
Now do the same thing only add waist bend to get your helicopter dealie moving on an inclined plane . . . your objective to keep your hands and arms moving in the same inclined plane . . . to do this notice what your hips and spine have to do . . . . there is a lot of stuff going on below your shoulders to keep your hands moving in that orbit without disrupting it . . . and alot of it is hips sliding and spine flexing and extending . . . . on the way back and through.
OK . . . . stick your arms out from your shoulders parallel to the ground . . . .
Now make your hands move parallel to the ground in a cicle by turning like you were a helicopter. . . . your spine is ONLY required to twist to keep them on that horizontal plane . . .
Now do the same thing only add waist bend to get your helicopter dealie moving on an inclined plane . . . your objective to keep your hands and arms moving in the same inclined plane . . . to do this notice what your hips and spine have to do . . . . there is a lot of stuff going on below your shoulders to keep your hands moving in that orbit without disrupting it . . . and alot of it is hips sliding and spine flexing and extending . . . . on the way back and through.
When I mentally envisage an axis of rotation in the downswing, then I actually do imagine that the axis of rotation is a diagonal line drawn between the left foot and the upper swing center. In other words, I can more easily imagine an axis of rotation that is diagonally aligned rather than vertically aligned (and which is also centralised between the feet).
On page 53 of his book, VJ drew a diagonally slanted line going through the torso - that follows the diagnonal line that I just described.
However, then on page 37 of VJ's book - figure 11 shows a pivot axis line (in white) at impact that is vertically oriented, going from the left inner foot to the left shoulder socket. That's why I don't know what to make of VJ's pivot axis concept, where the pivot axis apparently changes its axis of rotation during the downswing.
Hybrid Mode
