Monday, March 28, 2016

Robert 2

Today’s session turned out to be a full technical lesson for those with a bit less confidence than yesterday’s off piste group. Nina wasn’t going to participate initially but I encouraged her to come with the promise that we would just be working on easy slopes where there would be no reason for anxiety.

The video clip is of skiing prior to the coaching – just for the record. There’s not much point in assessing the skiing at this stage because the idea of the session was to completely change everyone’s perception of skiing and provide a new base for building skills. Individual feedback is more useful later on – after working for a while on the new material.  However it’s worth just mentioning a few major technical characteristics for each individual – without relating this to the actual skiing level: Nina: Rotation and Stemming Ollie: Heel Pushing and feet jammed together  Felicity: Rotation and Heel Pushing Bridget: At ease  - but Heel Pushing and feet jammed together Mary: Good Natural Timing and overall movement – only needs to be aware of how to take it further Clia: Well trained but Stemming left ski and timing off due to pole use.

There’s no point going into further detail because all those issues are a result of previous training. It’s only after re-training that feedback can be used constructively. The main thing to note here was that everyone was open and receptive to learning so we successfully covered a lot of ground in a few short hours.


Feet


We began with the feet. In the video if you slow it down (speed control on bottom right of the video) you can see that to varying degrees everyone is twisting their feet and skis into the turns – and some are stemming or pushing their heels outwards too. I asked everyone what they had been taught about the feet in skiing and nobody could think of anything.

Weight should be centred under the ankle – corresponding with the front of the heel. The shin should still contact the front of the boot nearly all the time. When bending and keeping weight off the fronts of the feet the ankle reflexively stiffens and the anterior tibialis (muscle on the outside of the shin) tenses up for support – all the resultant bending taking place is in the knees and hips instead. It’s important for the ankle to be strong in this way. If weight is spread over the whole foot instead the ankle generally collapses when bending and this disguised by the stiff boots holding the skier up. 

With the weight on the front of the heel the foot can be rolled onto its edges using the subtaler joint beneath the ankle. This doesn’t happen when weight is spread over the whole foot – the knee wobbles around instead when you attempt to roll the foot on edge. Rolling the foot onto its inside edge from the subtaler joint has the characteristic effect of tensing the adductor muscles in the upper leg (inside of the leg). When skiing both feet should be rolled onto their inside edges simultaneously (even when carving!)

When the foot is rolled onto its inside edge it actually turns away from the direction the ski is turning – the opposite of twisting the foot into a turn which has the effect of flattening the foot and forcing it onto its outside edge. When correctly executed this is similar to skating – you do not twist skates into a turn either. The muscle use is  more exaggerated in skiing because the edge of the ski is not under the centre of the foot but is displaced to the inside – so holding the ski and foot on edge requires more effort due to leverage. Ski boots provide lateral support (shaft running up the leg) so as to prevent the ski and foot from forced flattening. Overall, edging is actually created through body inclination and angulation – so the use of the foot is really about body control - not edging!

There are many more things that can be done with the muscles in the feet but the above is a solid base for skill building. It’s better to avoid orthotic foot supports and to learn to use the foot muscles instead. Boots need to have enough room to be able to roll and make shapes (arches) with the feet inside them.

Unfortunately there was no time for indoor work for everyone to directly experience the effects  described above with no ski boots on and to feel how this alters movement. I wanted simply to provide the tools to prepare the way to introduce dynamics. Good use of the feet and adductors is necessary for successful dynamics.



Dynamics


Everyone was using dynamics naturally to some degree in their skiing – some more than others. Nobody however was aware of dynamics. Dynamics took quite a bit of explaining as the difference between statics and dynamics appeared to cause a fair bit of confusion initially – which is to be expected when people have previously learned everything based upon inappropriate mechanics. We carried out my usual basic exercises and progression for dynamics and details can be found on the fixed page here: http://skiinstruction.blogspot.fr/p/dynamics.html

Most people commented on how different it made their skiing feel to work with dynamics directly – and we took it into some safe off piste just to show how the dynamics facilitates this. Dynamics is about using the centre of mass (between the naval and the pelvis) to control the skis. You gradually become aware of moving the centre of mass. A skater or dancer for example spins or rolls around the centre of mass – and bicycles, skates or skis respond to its motion. Unfortunately standard ski instruction trains you to actually move it in the wrong direction and although anyone who continues to ski will have overcome this naturally to some degree it is very different when the centre of mass is used actively and consciously in the right direction.

Completing this part of the session on dynamics I asked everyone to work up from the feet – rolling the outside foot in the turn onto its inside edge and then feeling the adductors on this leg pulling inwards and connecting this together with moving the centre of mass inwards in the direction of the turn. Later I asked everyone to reverse the order and start with the centre of mass working down to the feet. This is because eventually (not today) I would add some powerful postural control mechanisms which involve the core and lumbar spine and all motion (and alignment) would have to start and spread out from  the centre of the body. The idea is to work with the centre of the body in all ways – and to even centre your attention (your mind) on this. Anxiety vanishes when focus is internalised – whether on breathing in meditation or on detailed body actions when engaging in more athletic activity.

Describing "centripetal force" the analogy of a ball on a string was used. The ball being spun around your head only has one force - from the string - pulling inwards constantly away from a straight line (tangent). There is no "centrifugal" outwards force on the ball. Likewise the skier has to become this piece of string - everything pulling inwards. This is very counterintuitive because there is a strong illusion of outwards force when skiing and people defensively push out and brace against it - having been encouraged to do so from their initial brainwashing in the snowplough.

Timing had only briefly been mentioned so far by using the analogy of a motorbike – falling down into a turn and being brought back up at the end. Toppling over sideways with dynamics is exactly the same principle – creating a down/up timing naturally. Skis are built to work with this timing at a fundamental mechanical level. Mary had this timing naturally in her skiing and so did Clia – but for Clia it was being interfered with from her pole planting and the up/down timing she had been trained to use instead. When Clia simply toppled and followed the skis around with her body for this exercise she simply stopped using her poles – which is great. Pole planting does not serve a purpose when using active dynamics (eg. racing) other than as a pole touch after coming up and when entering the next turn. In 1994 the American system abolished pole planting and replaced it with a pole touch – but as we will see later this too is a mistake of dogma because there are valid different ways to use poles!

I explained that skiing is not about trying to stay upright – it is about trying to fall over. Dynamic Range is probably the clearest defining quality of a skier’s level. Most people can only topple to about 15° from the perpendicular to the slope whereas Bode Miller on the Face de Bellevarde managed 90° in the world championship downhill – actually ending up lying on the ground with both skis in the air,  totally recovering and not losing significant time. Most of racing technique is about how to extend this dynamic range. The skis become exponentially more powerful as the dynamic range increases and grip increases. On a bike, tyre grip poses a severe limit that skiers are not affected with. Grip on ice requires good timing, sharp edges and the nerve to go all the way down - when every fibre in your body is screaming "stay upright"! Most people - trying to stay in balance - never get even close to discovering this.

Skating 


Only a brief amount of time was spent working on skating. Some of the details of very basic skating and about the feet can be found at the following fixed page:
http://skiinstruction.blogspot.fr/p/beginners.html

Skiing is built from a combination of skating and dynamics. Feet placed on their inside edges and use of the adductors are critical for skating and of course so is directing the centre of mass. When teaching beginners those actions are the key to success – and they are the exact opposite from snowplough even in terms of he muscle groups used. In snowplough the skis are converging at the tips and the abductors (external upper leg muscles) are used to push the ski out – then the centre of mass is moved in the wrong direction etc. etc. Here we simply made skating step turns to change direction incrementally. When teaching beginners you start out like this then remove the actual step and still move the centre of mass and within the first hour the beginner is skiing parallel.

One other way to distinguish levels of skiers is whether they displace their skis to the side or displace their centre of mass inwards - the two are mutually exclusive! Poor skiers move their feet - good skiers move their body. When you see short turns with the body apparently totally still it's an optical illusion! The turn cancels out the motion of the body so it isn't visible. 

To keep things brief we used “direct method” – giving everyone a chance to feel the effects of skating in skiing. The idea is to skate straight downhill and then as speed builds to fall to the inside of each stride slightly so that dynamics is introduced and gradually over several strides the straight line of each stride is replaced by an arc. The point is that skating transforms into skiing – the legs continuing to work the same way – down//up and the dynamics also going down/up. The students should now be able to see that the correct functional use of the legs and correct timing is actually skating. When Ollie did this he came off the backs of his ski boots for the first time – naturally and without prompting. This is the powerful rhythm and timing that works off piste.

The job of the skier is to fall over – and the job of the ski is to lift up. When the turn comes close to its end the resistance against gravity builds up pressure and the ski lifts you up and out of the turn if you allow it to. Coordinate this with the upwards muscular action of the skate and the effect is amplified. Load up the ski base with powder snow and you end up bouncing. When all coordinated correctly this becomes a resonance – which is the essence of efficiency. Racing is actually very tightly controlled regarding rules around rhythm and rhythm braking – and correspondingly race course setters in France require a license.

Nina was given a short introduction to skating but was happy to just observe the more demanding aspects. Bridget managed a strong effort with skating downhill and had the clearest result – though her weaker dynamics especially on the left leg were the main limitation.

Pivoting


With Bridget’s ACL repair in mind it was necessary to press on and introduce pivoting. I’d asked how the injury happened and it was a classic case of trying to twist the ski into a turn in a tight situation in a couloir. When the ski is on its inside edge you simply can’t twist it – yet that’s what people are actually taught to do in snowplough and it’s called “steering”.

Visual perception works in reverse from how most people imagine. You cannot look at something complex and simply work out what is happening. I suspect magicians know this very well. People however look at skiers and think they can see everything – but they only actually see what they understand and are blind to the rest. When shown the skating/skiing connection everyone would have been able to then see it – but not before. All they would have perceived previously was that the best skiers were doing something different – and the rest would just feel like bafflement. Correspondingly I gave everyone the opportunity to try to spot what I was doing differently in a pivot demonstration right in front of them (having already dropped clues). Naturally nobody could see what was fundamentally different. The difference was that the entire first half of the turn was executed on the outside edge of the ski. That is a pretty huge difference to miss!

There are detailed demos of pivoting on the following fixed page:
http://skiinstruction.blogspot.fr/p/pivot.html

Earlier I’d asked Clia not to use poles and not to have the feet close together. The pivot is where both of those things can be use appropriately – as explained on the fixed page. In assisting each skier though a pivot so as to feel the effect I stood below and held the skier up – taking the body weight and acting as a substitute for the ski pole. This allowed me to control the centre of mass and lead the ski slipping sideways into a clean pivot.

Our earlier dynamcis was carried out with forward motion – the most pure form being a carve (which we didn’t work on). With pure pivoting there is no forward motion – the ski goes entirely sideways into the turn. Those are the two forms that need to be separated out and fully understood and only then can they be blended as required.

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