Sunday, December 26, 2010

Vedat's Progress

Vedat experienced some difficulty off piste in challenging snow conditions so he allowed his father to push him into a lesson. By himself I don't think he would have done it because he prefers his nice warm bed instead. Regardless of motivational issues he learned very well during the lesson and only complained about wanting to sleep and feeling cold about five or six times.

To begin this lesson I first looked at Vedat's skiing to study his problems. He had been falling over to the outside of the turns in difficult snow - so there was already a clear indicator - but it was necessary to look more carefully because he already has a good level of skiing ability. Filmed from behind you can see that he stems quite badly occasionally, and has quite a pronounced hip rotation. The stem becomes hidden when he gets moving because it then truns into a push out to the side of both skis, rushing the start of the turn. As the turn progresses his hips follow the turn with the skis, bringing his center of mass (CM) out of the turn too early and causing him to attempt to compensate by twisting his spine and bending it sideways. This action of the spine gives an odd look to the stance and the failure to keep the CM inside the turn is what eventually causes him to fall over in tough conditions.

From those observations it was clear that culprit was the "pushing out" of the skis. Once that was dealt with his posture would have to be improved - but because the bad posture is actually caused by the "pushing out" there was no point in dressing posture until the "pushing out" could be stopped.

Exercise one: Pull Inwards
Vedat had worked on this before so that helped us - and not much explanation was necessary. Placing a pole in the ground just to the inside of Vedat's ski tip and asking him to lift the ski slightly off the ground and to pull the inside tip of the ski against the pole revealed that the tail of the ski pushed outwards. This means that he was actually twisting (steering) his foot and not pulling sideways with is adductor muscles. When the adductor muscles are correctly used the tail actulaly comes inwards because of the tip being blocked by the ski pole.
We used this little exercise to establish the correct muscular sensations and then applied them to the snow. The idea was to sideslip on the top edge of the top ski and to repeat the "pull inwards" of the tip. As there is no resistance from the inside edge of the ski the tip slides downhill and the skier goes into a smooth and quick turn. After a few failed attempts and tantrums Vedat got it right and could clearly feel the difference.In the following video the legs and skis are being used correctly but there is a massive body rotation which we then had to go on to deal with. It is important in this exercise to keep both feet downhill of the CM and to reduce dynalics accordingly.

Exercise two: Indoors Posture Correction
To work on posture we first of all had to go indoors and remove our jackets. Out on the slope I got Vedat to grab my hands and pull me with his skis across the hill and upper body facing downhill. All the strain was taken in his spine and it made his back hurt so we couldn't begin to deal with the issue directly on the slope.
Indoors we managed to get his body to flex and move around the hip joint instead of around the spine. We developed the appropriate feelings for upper/lower body separation so that by flexing he could keep his feet parallel (together) and turn his pelvis (belly button) around to one side or the other - with no twisting taking place in the spine. We also worked on simulating a turn and showing that the hips didn't follow the skis around but that the pelvis actually resisted turning and the bottom would drop deeper into the turn. Until now Vedat's pelvis would always follow the skis and so he couldn't drop his weight into the turn as it progressed (this being called "hip rotation").

Exercise three: Upper Lower Body Separation
Back on the slopes we now worked on being able to get the skis to turn and the legs to turn independently in the hip sockets, but without the upper body swinging around. It should feel like the legs work like two windscreen wipers and the body remains still. The hip joints are where the "windscreen wipers" pivot.
In fall line skiing this separation of upper and lower body is what permits the skier to sink down into the turn and prevents himself from being kicked out of the turn prematurely.
The ski's job is to lift the skier up out of a turn (out of a fall) and as a turn progresses the forces align with gravity and the tendency to be lifted up become overwhelming. If the skier is at an angle to the slope slightly closer to the perpendicular  than to the vertical, then he will even literally fall out of the turn. If the snow is soft the ski loads up like a trampoline over its entire base and the lifting effect is magnified again. Any hip rotation with all of this combined guarantees a fall near the end of the turn when in wind packed snow or tricky conditions.
The main reason for not being able to relax the hip joint and to separate the upper and lower body is because of the habit of "pushing out" of the ski in the turn. This causes the leg to extend and to lock up the hip hoint forcing the pelvis to turn with the skis and setting up the entire list of problems that Vedat was experiencing. It generates "resistance" where muscles end up fighting against each other and the skier becomes efectively weak.

To facilitate the turn it is best to exaggerate up and down motion - which also enhances the effect of "dropping in" the inside of the turn. The push up is at the end of the turn (as in skating) and matches the dynamics (motorbike riding up at the end of a turn).

In the following video clip Vedat has mastered most of the details of the exercises above, but there is still a slight hip rotation and kink in the spine.

Finally, Vedat applying his new skills off piste in fresh snow - fall line skiing. This is quite impressive because he does a good job holding it all together in harder conditions. Later on we went onto a steep pitch with deeper snow and poor visibility and he found that he couldn't hold it together - but that is completely normal. New skills need practise before they become unconscious and automatic and can be applied under stress.

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