Tuesday, December 28, 2010

Audrey & Huw Day 3

Huw suggested that we start from scratch - pretending that he had never skied before and had to learn skiing without a snowplough and all the associated trauma. The idea behind this was that all the muscle memory and apprehension causing Huw to tense up and hold back in his skiing may be due to the lack of control experienced from the traditional way of learning - and there is probably a lot of truth in that.

Exercise one: Skating turns on the flat.
We began by skating in circles on the flat - like someone might do with cross country skis. This rapidly exposed some fundamental problems. Huw was not able to propel himself and didn't realise that skating involves a purely lateral push off from the inside edge of the foot. The "diverging skis" causes the forward travel - much like a sail boat tacking against the wind. To begin with Huw was trying to push forward from the foot - as in walking. Once the correct action was understood he then managed to find out how to glide on the diverging ski with the propulsion - and he was on his way. Audrey to begin with failed to grip with the ski edge and get a proper push off. This is common with skiers who "push away" the ski in a turn when stemming - instead of gripping with the ski and moving the body. In fact one of the main differences in levels of skier is that poor skiers displace their feet laterally and good skiers displace their centre of mass (CM) instead.

Exercise two: Traversing with diverging skis.
We quickly moved on to traversing with diverging skis - so that speed and control came from the uphill edge of the uphill ski and the lower ski was pointing downhill slightly but available for support. This permits a controlled traverse/sideslip with skis diverging and a strong sense of security.

Exercise three: Turn made with diverging skis.
From standing on the uphill ski (uphill edge) just a slight movement of the CM downhill and forward - in the direction of the diverging ski - causes a turn to commence. The adductor muscles have to be held tight (as in skating) and the CM moves exactly as in skating but propelled only by gravity. The turning ski does not get onto its inside edge until it crosses the fall line - so the ski acts as a brake during the first half of the turn - not as an accelerator as would happen in a snowplough. Huw managed this well but Audrey was compromised due to her poor stance in her ski boots - so we had to alter the orientation of the lesson to deal with this.

Exercise four: Stance correction - standing upright "like a man!"
Audrey was leaning heavily on the front of her ski boots and this meant that she was simply not "standing up". Ski boots can support your weight but they are not designed for that job - that's a job for the leg muscles and bones alone. Audrey didn't realise that she could stand up by pushing the back of her boots straight with the back of her leg - and that this is not the same as leaning on the back of the boot. In reality it is ony when jumping that this would have to be done in skiing - though champion racers such as Killy were known to have cut away the back of the boots to permit a straighter stance and to push the skis and feet further forward. When skating and propelling the body forwards the leg is easily straightened with the boot even canted frowards at 12° - because the body moves forwards and the leg extends without pressing against the back of the boot. At the end of a skate even the ankle is extended and the foot moves up onto the ball as it would when running.

Exercise five: Foot - boot - stance connection.
Indoors we looked at how to activate the muscles across the top of the foot and the anterior tibialis - to strengthen the ankle joint and create a powerful support from a stance on the ball of the foot. Audrey has pretty much double jointed ankles so this was a necessary exercise to try to stabilise everything there. The foot has to be placed on its outside edge and the the ball just behind the big toe stretched toward the floor. Once the stretch is as great as it can be the foot is allowed to roll off the outside edge so that the ball comes in conact with the floor. This activates the foot muscles and anterior tibialis (muscle running up the outside of the shin bone) - ans stabilises the ankle joint. Flexing when skiing now then takes place at the knees and hips - not at the ankles. A stiff ski boot is recommended to work along with this stance and to help to maintain it.  A boot which easily collapses forwards and doesn't bounce the skier back into position when required is no good for interracting with skis on a hard piste. (though such boots may be OK for certain off-piste conditions)

Exercise six: Skiing on one hip.
The skating action causes the body to place the skier on one hip joint or the other - making a clear switch possible. Most skiers stand on two hips causing a confusion of feedback and reflexive responses from the body. The skis and the body only really function correctly if the skier is placed over one hip joint and the whole body can rotate around it. This can be done with both skis on the snow and it takes a trained eye to still see if the skier is "two footed" in an inappropriate manner or not. We did a few exercises for getting onto one hip with the new more upright stance that had been worked on. At one point this even meant lifting one buttock with a free hand - the inside buttock from the start to the end of the turn. Simply standing on the uphill leg strongly and then stretching the downhill side of the body so that it is raised higher than the uphill side (and then kept that way during a turn)  is a good way to enforce a strong one legged stance. It is always best to try to keep the inside ski on the snow during the turn to avoid excessive instability.

Exercise seven: Adjusting for the axis of travel.
Yesterday we worked on moving the body forward to start the turn but today the issue was developed a little further. Two axes were identified - one across the hill (horizontal) and the other in the plane of the slope - perhaps 20° downhill. It was clarified that when the skis turn downhill the skier has to orient his body from horizontal to 20° - by tilting forward from the feet. Failure to do so means that the body is left standing "vertical" and appears to have been left behind at the start of the turn. Both Huw and Audrey with their stronger stance were able to engage more effective turns when they managed to make this adjustment.

Exercise eight: Lowering stance to increase angulation for gripping on ice.
It was pointed out that on steep icy slopes the upright stance is probably not the most appropriate due to the need for a lower and more flexed stance to generate angulation and to keep the CM well uphill making the skis bite and loading up required pressure for gripping.

Exercise nine: Increased dynamics.
It was time to try to get Huw to move so we started with some bigger and more deliberate dynamics movements at the start of the turns - by really trying to "fall over". Huw found that a genuine attempt to "fall" was not really what he was doing - though that is what is required. The skier's job is to fall and the ski's job is to bring the skier back up. The ski is much more powerful than the skier and unlike a bicycle where tyre rubber has limited grip - the ski's edges become more effective the greater the dynamics.

Exercise ten: Proactive dynamics.
The secret about dynamics is that it is not "reactive" it is "proactive". You do not wait for the ski to respond - although that is exactly what most recreational skiers do. without realising it They stem the ski and wait until there is a strong rsponse from the edge before comitting to that ski. - or they move cautiously with the CM to begin the turn. Really good skiers just move the CM convincingly and then the ski kicks in later. It requires confidence to do this and the awareness that the ski will respond.

Audrey is experimenting here with moving the body from side to side rapidly and getting the skis to respond quite successfully - very well done for a first attempt.

Exercise eleven: 3D skiing with timing shift.
When using Proactive Dynamics this approaches the type of movement used in slalom racing. The skis are not trying to pivot on a flat 2D surface but are trying to cut out small banked tracks on a 3D surface - so the skis are always travelling "forwards". This makes high speed skiing much safer and more stable and is a far cry from your average Parisian punter "heel pusher" pushing the snow from side to side in his high speed fall line sideslip. When moving the body rapidly and powerfully from side to side like this the apex of the turn is actually in the fall line - not at the bottom of the turn across the hill as in a pivoted or a rounded turn. This sort of timing and rhythm are also excellent for skiing in crud or windpack off piste to avoid over pressuring the skis at the end of the turn and hooking the skis unpredictably.

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