Visual aid for COM and leg lengths through transition?

You can practice skating.  Skating has lots of extension and center of mass movements in it. 

As for a visual aid, you can tell them to plant their poles a few inches further down the hill than they normally would. This will force them to move their center of mass more into the turn and the extension will happen as a result of it.

Also another thing to add is to be careful about teaching up and down movements, extension is a directional movement. But I think you have the idea since you want people to extend their outside leg (and shorten the inside one).

Here is a good video that demonstrates the efficient and inefficient extension.

As you can see at about 18 seconds in he starts to move up to extend.

Quote:

Originally Posted by pdxammo 

Thanks, that's not quite it though, the folks I'm trying to help aren't capable of that much lateral movement. I should clarify that the extension of the new outside leg is not preceded by a softening or shortening of the old outside leg. The extension is very up and the CoM is much delayed in coming across and the movement is not along the ski. The shape of the turn suffers.

   Very visual learners here so conceptual explanations are not effective. Some hand modeling helped but it needs more re-inforcement.

Have you seen the Sofa Ski School dvd?

http://www.sofaskischool.com/

Klaus has some video lessons online and the dvd is quite cheap. One little thing helped me alot - going from the ready position (knees bent, skis about 45 degrees to the fall line), initiate the turn by standing up "out and over" facing down the hill. You naturally start moving, the skis flex and the turn initiates.  As they cross the fall line they pull their knees up to their chest and repeat on the other side, extending both legs and standing up out and over the hill facing down the fall line.

Hope this helps.

Use their ski pole....during a static demo, hold thier pole to their knee and shoulder, as they flex and extend their shoulder should slide up and down the pole.  If you hold the pole vertical, the movement will be vertical...hold it slightly angled forward, and their movement will necessarily follow.  Do this static demo a few times, till they get it...then let them try to dublicate that same "feeling" or "movement" when skiing. 

I have seen many students with this same issue.  Its amazing how even in a static demo you might have to do it a few times for them to be able to keep the shoulder on the pole, but once they get it...they got it.  This pole trick works just about 100% of the time.

Quote:

Originally Posted by pdxammo 

Does anyone have a video, model, or other visualization aid for how leg length change can facilitate transition.

You might try poking around here if you haven't already...

http://ronlemaster.com/images.html

I've got this one on my desktop - like to look at it and wonder/ponder. ;-)

http://ronlemaster.com/images/2006-2007-B/slides/ligety-aare-2006-gs-1.html