Friday, February 11, 2011

Hakan

Hakan has only been skiing for about two weeks and never learned with a snowplough apparently. When questioned about ski technique he has received in coaching his responses are accurate and well above average in terms of detail and comprehension - yet ironically,  that's precisely why he is still not comfortable with what he is doing. He described what he was doing in the following terms:
  • Come up to start the turn
  • transfer weight to the outside (uphill) ski
  • Push the heels/feet out to the side (hockey stop manner)
  • Push inwards with the big toe, twisting the foot in the direction of the turn
  • Bend the ankle and lean forwards
  • Face downhill all the time
  • Come down to finish and plant the pole
The first video scene is of the infamous "heel push" and the second scene was about half an hour later after dynamics was introduced and the heel push had practically disappeared and was replaced by smooth stable turns and an effective and natural use of the Centre of Mass to control the turns

Music by Loreena Mckennitt - The Gates of Istanbul - appropriate Scottish/Turkish connection...

Apart from the pushing out of the heels every detail is part of standard ski instruction and totally incorrect.  The pushing out of the heels is also incorrect. Several years ago after teaching the alternative to ex Formula 1 world champion Damon Hill he asked me if he could collect the money back for the 40 years previously that he had been taught a load of nonsense. Hill is a talented athlete and was able to appreciate very rapidly the benefits of looking at skiing from a much more natural and intelligent perspective. He quickly related the new perspective to his racing experience. When something makes sense then you can always relate it to other things. When it is nonsense then you can't.

Dynamics Part 1
Hakan had one of the strongest "heel pushes" that I've ever seen so to try to combat it directly the best approach was to launch straight into dynamics. I explained the fallacy of "balance" and need for a shift in perception towards seeing the required goal as "actively falling over" instead of staying statically upright.
To clarify the issue Hakan was shown what happens when we try to balance over a leg - to transfer the weight to it as in traditional ski instruction. To transfer the weight to the right leg you mover the Centre of Mass (CM) to the right - to get it above the foot. This is what is looked for and described in traditional instruction and practised in exercises and it is what Hakan was trying to do up until now. The problem is that you are asked to do this in order to turn left - but you are required to move your CM to the right!!!!! This is wrong. There is another way to get pressure on the right leg and it is by doing the exact opposite - by accelerating the CM in the intended direction of travel. The key word here is "acceleration".

We followed the standard introduction to dynamics with Hakan pushing his shoulder against mine and feeling the effects of pressure on the feet - and observing the direction of travel of the body while doing this.  With me standing to his left, downhill, I had Hakan push his shoulder against mine - to his left, moving his CM to the left and feeling the pressure on his right foot. The force on his shoulder is an artificial aid which is replaced by angular acceleration when in motion on the skis (F<=>MA and so forces and accelerations are interchangeable) - but the force though the feet is identical as when skiing. Moving rapidly against me (accelerating) there is force on the right foot from the start of the movement. Sustaining pressure against my shoulder also sustains pressure on the right foot. Only moving across slowly towards me did the pressure go on the left foot instead - because that slow motion is not dynamics - it is statics. The trick is to accelerate the CM in the direction that you want to turn - and to do this you must try to fall over to that side of the skis - but while standing strongly on your leg.

The problem skiers have is not one of staying upright - it's that they can't fall over to the side no matter how hard they try. They will only fall if they fail to stand on the supporting leg for some other reason. Most intermediate skiers cannot generate inclination of more than about 20° whereas elite racers can practically get their bodies on the ground at speeds of up to 80mph. The development of the skier centres on extending their dynamic range  - not in developing "balance".


Hakan's first turns with dynamics were from running straight down the fall line and turning out to one side. This simplifies the issue and makes it easier to grasp. This was followed with shallow linked turns. Basically the action is so natural that Hakan picked it up initially with little difficulty.

Dynamics Part 2
For the second part of dynamics I explained that we have to come back up out of the turn. This is the tricky part. Motorbikes do the same - in and out of turns but they are on flat ground where vertical and "perpendicular" to the ground mean the same thing. In skiing we are on a slope where those two things are different - there is an fact a break in symmetry which leads to new things. For developing dynamics we have to think of the end of the turn as being "perpendicular"; the skis flat on the surface and the skier tilted downhill away from the vertical and so perpendicular to the slope as he moves across it. The skier in this position is now completely back up and out of the turn, like a motorbike would be on the road. - but the skier must now continue to fall into the next turn as the edges of the skis change to the downhill edges.
To achieve all of this the skier has to stand on the outside ski in the turn - letting it bring him up - right to the end of the turn and until the skis are flat. Most people will not even attempt this until they are made aware that it is not only possible but essential.

Timing
The timing from dynamics is Down then Up corresponding to the CM dropping down into the turn and then coming back up out of it. (Opposite of that taught in ski school)

Function of the Ski
If the skier's job is to "fall over" the ski's job is to "bring the skier up". This is how a bicycle works too. The skier is always in charge, both of instigating the falling over and then allowing the ski to bring him up. The ski however is generally much more powerful than the skier perceives and so the skier always errs in not dropping far enough down into the centre of the turn and never by over doing it. This problem is even greater in the second part of the turn where the forces involved are much larger.

Feet Rolling
Indoors we looked at the feet and how to relate them to the ski boots. Basically Hakan's current approach caused a weak and collapsed ankle and a twisting inwards of the knee and outwards of the heel. I explained that boots, legs and feet are not intended to work this way. The simplest approach to correct this is to stand on the heels, learn to rock feet from edge to edge at the subtalar joints beneath the ankles, and to relate this motion to the lateral motion of the CM in the same direction. With weight on the heels the bending is only from the knees and the hips and the ankle goes strong - preventing any form of twisting the knee inwards or leaning of the ski boots for support. I showed how the rocking of the foot inwards also tensed the adductor muscles on the inside of the leg. This muscle tension is important for "pulling inwards" and for gripping with the inside edge of the ski when skating. Leaning against a table and standing up in ski boots I showed that if the supporting foot was "pushed  out " to the side then there would be a slip. If the leg was "pulled inwards" then slipping would be prevented. This is precisely the application of the adductor muscles in skiing - pulling inwards - the opposite of pushing or twisting the heels outwards. I also explained the illusion of "centrifugal force" and the subjective (and incorrect) feeling of being thrown out of a turn  - and how it was a natural impulse to "brace" against it by pushing outwards and how we have to fight this impulse by pulling inwards instead to assist our equipment to carry out its function.

Basic Skating
Hakan is not a skater and had to begin by learning the correct coordination and use of the adductor muscles to grip with the edges. On skis the edges are not directly under the feet so the knees have to be pulled sightly inwards with the adductor muscles to be able to grip when skating. This is not the same as bending the ankles and twisting the knees inwards.

Skating and Timing - The Basic Pressure Cycle
Hakan was shown that the vertical movements involved in skating are synchronised with the vertical movements found in dynamics - down and up. In fact each turn on a ski is on one leg and is actually a skating stride taken into an arc. When the skating of the legs and the dynamics are in resonance they become very powerful, stable and effective. As an exercise I asked Hakan just to observe the pressure cycle under the feet when turning using only dynamics and to realise that it was identical to skating.
The skating was mainly being taught at this stage to encourage a strong independent use of the legs  - one leg to the other and standing strongly on the hips. This is also part of the development required to move away from a two footed heel push. Hakan had a tendency to fall off his left hip in particular instead of standing strongly on it. This was clearly down to a tendency to shy away  from putting force on the left leg - a very common issue.

Following the skis
Hakan was concerned about facing downhill but it was interesting to note that immediately on his first attempt at dynamics he naturally just followed the skis with his body. I encouraged him to do this for the time being so as to develop uncomplicated dynamics. Facing downhill too soon in a skier's development leads directly to a strong heel push and rushed start of the turn and we were trying to get away from all of that. The start of the turn should be the most prolonged part. I asked Hakan to just continue to follow the skis but to avoid "rotating" the body to force the skis to turn - which he sometimes tended to do.

Uphill Edge Pivot
I briefly demonstrated fall line skiing from the uphill edge of the uphill ski - just to show that it existed and was very important - but to also point out that there was enough for Hakan to work on without that for the time being.

Feedback
Observing Hakan's skiing at the end of the day there was still a strong tendency to push one heel out slightly at the start of the turn and that was destabilising his skiing considerably. You can't both push the heel out and move the CM inwards at the same time - they are mutually exclusive acts. We added the exercise of pulling inwards with the adductor muscles of the uphill leg - prior to turn initiation - to prevent any possibility of a heel push - and it appeared to strengthen his stance.

Conclusion
Hakan is still new to skiing and needs to be patient and work on the correct movement patterns in easy terrain for a while until they are assimilated and unconscious. This would already have happened had he started to learn with correct movement patterns from the beginning.

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