Tuesday, March 17, 2015

Ersin - Off Piste / Centre of Mass

Snow in Le Fornet had been blasted by high winds and so it was never going to be easy to ski. If Eskimos are supposed to have names for over 30 types of snow – then in the skiing world this one is called “educational” snow!

Although I was more focused on safety – the very high winds having formed the new snow into unstable slabs on top of a sun crust base (Avalanche risk 4) -  I was asked to observe Ersin with a view to eventually working on developing his skiing. Basically anyone who can stay on their feet in snow like this can ski and at first it’s actually quite hard to see anything “wrong” other than the snow itself.

The problem with giving a “critique” is that it’s easy to list symptoms  - which can easily be related to – but but not so easy to explain the underlying cause – which usually cannot be related to – hence the reason for the problems in the first place. I did mention the underlying cause was that the dynamics (motion of the centre of mass) in and out of the turn were faulty – but at this stage that’s a completely meaningless statement and so a list of symptoms had to come out as follows: Ski tails being pushed outwards to the side, hip rotation, having to jump to substitute for good dynamics at the end of the turn, postural problems (right side). I only picked up on a few key points but the reality was that the entire basic mechanics of the turn were fundamentally incorrect and there is no way to explain this without it being a full blown lesson – because it needs a different perception altogether.

ChiSkiing (Core Activation)

Following our last run off piste I rapidly looked at the issue of hip rotation with Ersin – explaining the difference between classic  “upper/lower body separation” and how it compresses the ribs towards the pelvis and disconnects the two halves of the body as the hip comes around in front of the pelvis. Then I had Ersin pull back his hip – holding the shoulders/ribs stationary – so this time he could feel a stretch of the abdomen and activation of the core muscles. I explained that this is the direct way to confront hip rotation – you pull it backwards during the turn instead of allowing it to swing forwards in front of the pelvis (making sure not to also pull back the shoulder or the foot). I demonstrated how the “separation” relates to old slalom technique (solid poles) and “integration” relates to modern slalom (breakaway poles).

We stopped for a coffee once Haluk started to cave in to back and knee pain. I’ve been telling Haluk for a while now that the reason for disc and joint degeneration is nutrition – and Fortunately Ersin who is also strongly interested in nutrition can back this up and add even more pressure to Haluk here!

It is surprisingly difficult to switch the mental mode from “guiding” to “teaching” because each is a job with very different responsibilities and focus. After th coffee break and re-focusing I chose a point of reference that would be meaningful from the start. The underlying principle I wanted to work on was regarding the control over the motion of the centre of mass – but the best way to enter into dialogue in this case would probably be to address the “pushing out” of the skis – through introducing the “pivot”.


There is a dedicated page on pivoting where detailed explanations can be found - here: http://www.skiinstruction.blogspot.fr/p/pivot.html

Ersin was exceptionally quick to pick up the pivot – essentially pulling it off correctly on the first attempt – for both an uphill ski pivot and a downhill ski pivot. Until it was pointed out to him he was unable (as is normal) to see that the ski was kept on the outside edge for the first half of the turn. My real goal was to get him to slide the ski inwards (instead of pushing it outwards) - into the new turn – it being impossible to push it outwards while being help on the outside edge. I then briefly mentioned the adductor muscles and that it was really the ski following the centre of mass into the turn. This was an exercise guaranteed to alert Ersin to the fact that there was a whole type of use of the skis and motion that he was until now unaware of. I know that experiencing this can be impressive – but the reality is that it is just the start of discovering “dynamics” and how to use the centre of mass to drive and control turns.

After lunch we picked up the pivot exercises once again but this time in more depth. I rapidly explained that we try to stand on the front of the heel just below the ankle so as to be able to use the joint (subtaler) beneath the ankle for rocking the foot. The aim was to stand on the uphill edge of the uphill ski and foot at the same time – then rock the foot onto its downhill (inside) edge while the shaft of the ski boot would hold the ski on its uphill (outside) edge. This separates the “edge of the ski” from the “edge of the foot”. The foot rocking was then related to the adductor muscles and going up through the glutes all the way to the core. The idea was to use the core to pull the ski (with all those muscles engaged) into the turn – using the ski pole to control the entry. I showed how the lateral pull of the adductors held the knee inwards in a strong and supportive manner – while going on the front of the foot, flexing the ankle and pushing the knee inwards was very unstable and weak. We did the brief exercise of pulling laterally against a ski pole with the tip of the ski to ensure the correct feelings were being recognised.

Even when using the downhill ski and pivoting on the “wrong edge” the same muscle movements need to be made – but towards the centre of the body – not the centre of the turn in this case. This clarifies that the turn is actually controlled exclusively by the centre of mass moving.

Ersin understood all of this but when actually skiing with it there was a problem. Even though he was moving everything “inwards” the timing was ineffective and there was no real understanding of “moving the centre of mass”. Ersin had it ingrained into him that skiing was about keeping the centre of mass stationary and moving the legs instead – which is a standard error of teaching. It was clear I would have to move into teaching “timing”.

(We had tried some short swings and jumping to make edge changes in mid air – but  the relevancy of the exercise was not connecting with Ersin.)

Skating (Timing)

Having explained the illusion of “centrifugal force” to Ersin it was time for him to feel how we generate the reality of centripetal (inwards) force. I got Ersin to push hard against my shoulder with his and explained that this was how to drive the body either into or out of a turn. The body has to be moved and the visual “stationary” appearance of the upper body in skiing is a visual illusion. The best way to feel the power needed is to skate turns – with three skates inwards making a turn. (I checked that Ersin could skate properly across the hill first). There is a strong motion of the centre of mass downhill to start the turn then it gets harder to move inwards as speed and gravity effects build up. Ersin connected with the feeling and managed to take this down to two skates and finally the correct rhythm from one skate – which resonates with the down/up pendulum effect of the centre of mass falling into a turn and rising back up out of it.

We then brought the pivoting and skating together to give control and power when pivoting on a steep slope. The push up from the lower leg supporting the body coming up and out of the turn – then the pulling inwards and pivoting into the next turn. Now Ersin was starting to feel how the centre of mass connects and drives the turns and how the skating principle is fundamental even if invisible to the untrained eye.

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