Saturday, December 17, 2016

Shiffrin Suffers through bad boots!

 The Michaela Shiffrin boot story.

The boots are so over powered, her edges are either on or off, she can't keep the tipping progrssive, that is why she is hurrying. The Cuffs of her Atomic boots and lower structure of the boot lock up her feet. She doing everthing from and with her adductors, no finesse.
The ski is flat at the most critical part of the arc?????
The knee is outboard, hip leaning away, so the ski can slide.
Sliding without commitment to angles?
Here Shiffrin gets the hip angulation the only kind available, but it's fleeting and often she doesn't have time to develop this. It's not ideal because it requires huge commitment and it very difficult at these speeds and on this surface to get in and out of this angle.




In this turn, she was able to drive the knee using her adductor muscles. "Explanation below!"
Another turn, she had to skid into, not putting the ski on edge progressively above the arc.

Again, here is a moment maybe 1/100 of a second where she was able to push the knee in to get some grip, but this is so fleeting she can't depend on it. And if she forces it at the wrong time, it's very dangerous. This is a highly vulnerable position for GS skiing.

First, before we all go crazy with these descriptions and reactions about Mikaela Shiffrin's trouble's on the GS course, you have to use accurate terminology. When describing or analyzing ski technique you have to be accurate about the forces in play. and you have to know the difference between, when the forces are reduced due to a skier's actions on purpose; or from where the skis are pointed relative to the falline.

As was often repeated, inaccurate terminology in the written analysis can mislead the actual causes of the problems trying to be shown. 

"Accuracy of movement and biomechanics must be logical." 

From the photos and from others doing analysis there is much confusion and misinterpretation by the so called experts, even racers themselves.

One description included these words.
"She can't release the hip", was often the terminology used. The hip doesn't release, there is no mechanism in the hip to release a ski. It has to come from the base, which is the ski edge and then the leg. 

You have to give up grip to release the CG or CM, which, I think is what the author was trying to convey.


Once you begin to focus on the actions of the ski edges, how they are angled or tipped, you can do movement analysis of the upper body's compensations. John Teague (ex-FIS racer) has the right approach, he is describing the problems at the bottom of the kinetic chain, which results in the upper body adaptive requirements. 

In Mikaela's's case, she has very little confidence in her GS skiing, which is obvious to everyone. She is skidding, sikvoting, and very late with angles. Because her boots are built to place her feet, ankles and cuffs out board. We call this supinated or inverted in medical terms. 

It's very difficult to get the ski progressively on edge with this situation. Her ankles and feet are basically blocked or locked out of eversion, (moving toward or getting the ski or boot on to the big toe edge side. This is very difficult or almost impossible to do with this set up, which means she has to use adductors muscles on the medial side of her leg, to drive the knee and ski on edge. 

She does this in combination with leaning and skivoting  because without the skids, the edges would be uncontrollable, and harsh. "like a highly railed ski" However, once she gets to a certain point under the gate she can lever over the outside ski, with her knee drive, using the adductors to create edge angles and grip. But this only happens temporarily.

Problem with this, it's like a light switch, on, fully on or off. And once she goes for the "ON" knee drive, the knee drives excessively to an "A" frame", a highly vulnerable situation, because all the load comes at once. This feels horrible and it hurts, that is why she is so tentative, she doesn't trust it. 

And as some have already mentioned, it's very difficult to release an "A frame" that is the only thing holding the arc. My 25 cents! The sad part, the techs and the coaches either don't see it,  or don't have a solution.











2 comments:

Progetto Fallenlands said...

Looking good: It seems to me actually right what you are saying.

Harald Harb said...

Yes, because they actually did change some things and now she can get the ski on edge under her body, still a way to go, but much better.