Originally Posted by bud heishman
Originally Posted by yogaman
I'm not following what you are doing with your feet at all. Also want to know what it means to look at things on a strictly biomechanics viewpoint. As for beginners carving, if you are talking about railed edges you are right, but what about brushed carves? I think the thread started out about wedge christies. YM
Yes, this is where we are using the terms interchangeably it seems. What I have historically called steering which I define as a blend of edging and rotary (albeit self steering characteristics of the skis as opposed to muscular twisting of the skis which some insist is what PSIA is suggesting) is being termed "brushing" which seems an awful lot like using the self steering characteristics of the skis in a passive manner (which I still refer to as a rotary skill). We need to control this rotary effect of the skis to shape the turns. So I think we are talking apples and apples it's just that one camp calls it brushing and the other calls it steering which is the classic definition.
Twist n Tip is the term I use for the biomechanics function of the ankle and foot's planes of motion. We know the foot/ankle complex can invert/evert, dorsi flex/plantar flex, and abduct/adduct right? these motions are linked in a triplainer motion. When we tip our right foot to the little toe edge (invert) the foot also twists toward the center line (adducts) and plantar flexes. So, if I twist my right foot to the left it tips onto the little toe side edge or to the right. So, if I want a high edge angle early in the turn intending to carve, twisting my feet to the left will tip them to the right side edges. It is a rotary skill to actually aid a carving entry. Some talk about resisting the twist, I talk about twisting left to carve right!
There appears to be a linguistic gap here. "If I twist my foot.." and "If my foot twists" are interpreted as two separate things by me and a lot of other people. Both terms maintain the angular triplainar relationship of the ankle. The only difference is that in the first one a torque is being applied to the ski by the skier, and in the second one the applied torque is not necessarily coming from the skier.
No system I have ever come across has ever said that rotary movements and control of same are not requirements of good skiing, though they may have been misinterpreted as such.
A third key to misunderstanding is that if the ski is not tipped relative to the plane of the snow, pressing the tip of the ski into the snow produces no torque in the plane of the ski, but if the ski is tipped on edge and therefore tipped relative to the plane of the snow, pressing the tip of the ski into the snow produces a torque in the plane of the ski, even though it produces no torque in the plane of the snow. So the person pressing down on the tip of the ski will feels as though they are applying a torque to the ski (because they are), but they are not applying any torque in the plane of the snow, so they are not "twisting the ski." They are applying rotary, but they are not "twisting the ski".
EDIT: When the PSIA message is being read as "point your skis in the direction you want to turn" by so many people (instructors and students), if muscular twisting of the skis (in the plane of the snow), as evidenced by their skiing and description of same, is not the message, perhaps PSIA needs to re-word the message.