Saturday, February 22, 2014

Alex 5

Today’s objective was to try  to get Alex’s legs active and produce a good skating rhythm and larger range of motion in his skiing. So far he had been bracing and resisting while leaning on the back of the ski boots for support and locking up all his leg muscles.

 

Warm Up – Skating

Immediately during the warm up run we were working on skating. Skiing is just disguised skating so anything that reinforces this connection helps.

Several things disguise the skating:

  1. Skiing is on a significant slope so movements are asymmetrical. (top part of a turn is with gravity and bottom against – until the very last part which is with gravity again)
  2. The two edges of the ski are not beneath the centre of the foot.
  3. There is a clear choice of edge use with extremely different effects.
  4. The ski edges and base provide separate mechanisms that cause a curved trajectory and not a straight line.
  5. There is a significant delay before the skis responds when using dynamics. (Unless strong muscular action is added)
  6. Sometimes due to high forces the timing of the legs and muscular impulses need to be reversed.
  7. Gravity induces the accelerations not the person.
  8. Fear, anxiety and tension are induced when accelerations are not confidently controlled.
  9. Because there is no apparent need to generate propulsion there appears to be no need to use a skating action.
  10. Terrain and surface are extremely varied.
  11. Ski schools teach the opposite timing from skating – despite the engineering of ski design being based on the opposite since around 1970.

This list could probably be considerably expanded. Short carving skis help enormously to overcome all of those issues – the shorter and more parabolic in shape the better. Modern racing skis are incredibly stupid in design and should be avoided. They have been produced to satisfy regulations in racing which prevent the use of carving skis. Carving skis were increasingly blamed on injury to young racers while the reality is that it was never the skis that were the problem but bad coaching, especially at higher levels. Only one modern racer appears to have overcome this regulation madness and that is Ted Ligety. Whereas the moronic coaches are all teaching their victims to stand up and skid the starts of the turns (now called “stivoting” instead of just “cr*p”) Ligety has managed to increase his dynamics and inclination and get the skis at almost 90° to the snow from near the start of the turn – which has the effect of getting the ski to carve tighter than its vaguely theoretical limits.

Alex is somewhere inside here again…

The regulation stupidity is pretty obvious because it limits the  “turn radius” of a ski – but anyone who understands skiing knows that even in classical design a ski has two turning circles – an upper and lower quadrant – and that the curve is not even close to being circular – being a golden mean spiral instead. The ski has at least two radii along its edge and the base and flex pattern and length of edge contact all have effects. Parabolic edge design (sidecut) also means there is not a radius. No “radius” can be measured on snow for the turning of a ski.

In skating along the flat the main propulsion should also come from gravity – but most people don’t see this. The person should “fall” between the diverging skis – aided by lifting one leg – falling forwards and at right angles to the ski still on the snow. The push with the leg should be to maintain height and the gravitational energy converts into propulsion (like a tree falling forwards) . This allows the bigger hip extensor muscles and the core muscles to be employed and not just the quads, so it is far less tiring. The feeling resembles just falling and picking up the trailing leg from behind. Additional muscular propulsion can be added in short bursts but should be reserved exactly for that purpose.

Mike  - not being a skater - discovered today that he could skate along the flat for the first time ever. It’s quite a natural action and very closely related to (correct) walking – but so heavily disguised by all the factors mentioned above that people are systematically driven away from it . It’s for this reason that ski schools produce droves of permanently technically impaired skiers with no hope of ever progressing. Mike has been able to benefit here from the catalyst of Alex’s rapid development and transformation – perhaps freed by the main focus being on Alex he has been able to digest and process information more effectively than in the past.

I reminded Alex to stay upright and pull back his hip (outside leg) when skating.

The main aspect of skating I wanted to work on today involved the turn completion. When completing the turn, if the turn is closed off (finished) properly with a build up of pressure then this pressure can be released by letting the ski bring you up  and out of the turn (by virtue of it continuing to turn and cut beneath the trajectory of your centre of mass). Timing the push up of the end of the skate with this turn completion allows the skier to become airborne. Tight high speed turns will create an airborne effect  even without trying to deliberately jump – but for the moment I wanted a deliberate jump. More advanced skiers actually have to absorb energy through flexing at this point to dampen the effect and avoid getting too airborne. Advanced skiing actually requires a blend whereby there is first a push up and then a retraction or compression right at the end.

Deliberately jumping out of a turn can be very playful – especially when there are small bumps or ridges available to use to assist the jump. The idea is to effect the complete turn transition in the air, landing on the new set of edges with the body already to the inside of the new turn.

Mike asked me why we might want to develop this. The reason is because the use of the supporting leg through the turn exit is fundamental. Whether bouncing with the whole ski loading up in powder or rebounding in jump turns when in crusty or wind packed snow – so as to allow the delicate turn transition to take place in mid air, or to direct momentum across the hill in a race course – this movement is basic and fundamental.

Short Swings

Both Alex and Mike were having trouble coordinating a proper “take off” – with Mike in particular tending to step instead of jump – so it was time to do some Short Swings. Short Swings are just exaggerated pivots. With exactly the same timing the powerful rebound (mostly downhill leg) makes the turn transition airborne and the tips of the skis are swung inwards into the new turn (much the same as they are in moguls when the tips are airborne.) This exercise succeeded in getting Alex somewhat off the back of his ski boots for a while. (The only other thing that worked for this was getting him to ski backwards!) Neither Alex nor Mike had enough angulation to be able to use their ski poles for support. The pole support in the pivot is what allows the body to be placed correctly for this very quick turn where the end and start of a turn combined take only a fraction of a second.

I explained to Alex that beginner skiers use a whole collection of “balancing” aids. They lean on the ski boots and the tails of the skis, stand with a very wide stance or snowplough for a large base of support, hold their bodies vertical (instead of perpendicular), block with the downhill ski at the start of a turn instead of falling into the turn and to top it off they try everything possible to stay in balance. Unfortunately the Ski Schools encourage all of this nonsense (except the back of the boots). The skier progresses by gradually removing every balancing mechanism until only the ski design is left – and that doesn’t work by balancing anything; it works by organising accelerations. We have to be flexible and dynamic with our legs having a large range of movement and in the right way.

After one run on a steeper slope I wanted to go up the Borsat to get a longer run of practising jumping transitions before going into slalom – but we were distracted by some skiable powder that was actually soft and deep enough to allow a degree of pivoting.

Off Piste

Alex definitely has improved dynamics and demonstrated that by staying in my deep off piste tracks. He still tends to incline much better when on his left leg and gets stuck over his right leg – which is the cause of most of his crashes (causing the flapping left ski to get caught and spin him around). Following my deep track however is good for his sense of rhythm and for giving him a physical (banked track) platform to improve his dynamics. Mike was spat out of his turns a couple of times – which only means one thing; not organising his dynamics appropriately! You either fight to keep your centre of mass inside the turn or you deliberately let it be brought up and out. When the result doesn’t match the intention then you fall. It’s not about being “out of balance” – you are always out of balance. It’s about organisation.

3D Banked Track

Following the example of Alex skiing in my ruts (which he did only because he thought it was a good strategy for avoiding rocks after we scraped over some on the ridge at the top) I explained to Alex how when skiing dynamically it’s best to visualise the skis banking over and literally creating a banked track for you. When a cyclist rides round an vélodrome he doesn’t have to turn the bike – it just runs forwards. Likewise it’s best to see the ski doing this too – in 3D - rather than turning on flat 2D ground. When you visualise this it’s easier to re-organise your body to create and respond to the forces involved in “banked track” skiing. I introduced this concept to help with potential issues with significant ruts in the upcoming slalom course!

Slalom

Alex wasn’t ready for the ruts in the slalom so we stopped after he wiped out twice on his first run. The problem was as usual his lack of inclination when standing on his right leg. He did manage a great Ted Ligety impersonation but unfortunately it was for all the wrong reasons – his skis slipping away from him and making him fall over. Alex reverted to compensating for lack of inclination by collapsing at the waist again. He tends to revert to this now only when in difficult situations and has not been complaining of a sore back again.

Alex impersonating Ted Ligety…

Independent Leg Pivots

Working our way down the Face there were a few issues of speed control with the dynamics and Mike pointed out that he picked up speed with the skating. I explained that the skating worked both ways – if the turn finishes early it causes acceleration but if the turn is closed properly it checks the advancement of the centre of mass downhill and controls the direction of momentum. It was now time to do some pivoting with the feet apart, independent and kept at the same height on the mountain (so no uphill/downhill ski). We worked first of all with no skis on just facing downhill with the heels dug in and feet apart with both ski poles downhill for support. The idea is to feel the legs rotate independently in the hip sockets and not have any movement of the pelvis or upper body above it. This wide stance and independent leg use allows the feeling of the push up from the outer leg to feel clear and to encourage its use for controlling speed.  The pivot with each leg separately makes closing off the turn easier as there is less body rotation to deal with – and dynamics can be kept to a minimum. This exercise appeared to work particularly well for Alex who connected properly with the push up/skating rhythm in short turns for the first time.

Mike had to be advised to avoid the pole plant again as it confused his timing. Mike was generally not managing to link the turns and access the rebound effect (which we practised with skis off with the independent leg pivots), but he was managing to use a push off from the lower leg more effectively. At the very end (video) Mike did manage to start to link some effective turns together.

Alex was tending to push his skis away from his body instead of moving the body (Centre of mass) inwards instead – same reason he falls in slalom. This has now become clearly visible due to the short dynamic turns he is able to make. Alex’s progress however over a handful of days has been very strong. The main thing is that by the end of this session Alex was starting to show movement in his legs and a clear skating rhythm – mostly thanks to his progress in the shorter turns where he could feel a rebound. Both Alex and Mike were starting to look like real skiers with effective timing and functional movement patterns.

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