Wednesday, January 19, 2011


Discussing Eilidh’s skiing prior to the lesson it was apparent that she had skied for a number of years but failed to progress to a satisfactory level. Jon suggested that it was perhaps a “head” issue, meaning fear and tension and also a “balance” issue. Without even seeing Eilidh on skis I informed Jon that this was almost certainly an incorrect assessment. Most “head” issues are actually technical issues at root and “balance” issues are simply not “balance” issues.

Demonstration and Assessment
Once we were on the training slope Eilidh demonstrated her current skiing level. It was clear to see that her skiing involved a long traverse, a stem (push out) of the upper ski followed by a shifting of her weight towards that ski – towards the outside of the turn. She was very upright, static, unstable and insecure. My earlier deduction about her “technical issues” was completely correct – and for the precise reasons that I had anticipated. Those reasons are not due to Eilidh making mistakes or doing something badly – they are due to her being intelligent, competent and her accurate application of inappropriate instruction – that is, standard, classic ski instruction. 

Prior to changing anything - the CM visibly moves in the wrong direction

After a moment’s reflection I decided to simply correct the basic problems directly rather than build up slowly from scratch. This proved to be the right choice as Eilidh responded positively right from the start.
Eilidh needed an explanation of dynamics. Most people are brainwashed into thinking that they are in balance when skiing, so they try their hardest to remain upright on two legs. Eilidh had been taught to transfer her weight to the “outside” ski. This is correct if your aim is to place your CM (Centre of mass) over that ski/foot and to balance on it in the vertical with gravity. Turning however is not about balancing, it is about generating accelerations other than gravity and to achieve that the body (CM) must move in the other direction – towards the inside of the turn.

Exercise one: The Wall -Five ways of moving
I removed my skis and stood uphill of Eilidh and asked her to lean against me with her shoulder against mine – and then push hard against me as if she was trying to push in a blocked door. Eilidh was pushing to her right and so was able to observe that all the pressure was on her left foot and leg with pressure being completely removed from the right leg. This pressure change was not intentional it was a "consequence". At this point already it is important to note the difference between cause and effect. 
I wanted Eilidh to use the "wall" to begin to explore five different ways of moving her Centre of Mass. Without explaining what was going on, the simple and natural act of pushing against the "wall" causes the entire body to incline, but creates a small angle at the hips with the legs being more inclined than the upper body. The skier at this stage doesn't need to think about this - or to analyse the shape of the body. Just practising pushing against the wall will get everything just about right. 
Way one: balance
The first thing I wanted Eilidh to feel was that if I asked her to place her weight on the left leg she would move her CM AWAY from me to "balance" over her left leg. 
Way two: feel the force (angular acceleration)
Next I asked Eilidh to push hard against me in the opposite direction from her previous movement. This creates even more force against the left leg than simply placing the CM above the foot because there is now the combined muscular force and gravity together. The point to note was that the directions of movement were opposite. The force against the shoulder would obviously not be present while skiing, but the force through the leg and foot would be identical. The explanation for this is revealed in Newton's second law of motion where F (force) = M(mass) x A(acceleration). The two sides of the equation are equal so quite simply the force F (against the shoulder) can be replace by an acceleration of the body. In this case that acceleration is provided when skiing by the ski itself and it is an angular acceleration. The "push" against the wall is replace by an identical "push" into the inside of the turn. Although this exercise is effectively static and the skier is really in balance against the shoulder - this is only a simulation of a dynamic activity. During skiing itself the skier would have to accept the quality of angular acceleration and all the risks implied - though the feeling though the body would be identical. The word "dynamic" comes from the Greek word for "power" - but it essentially means "unbalanced force" or "disequilibrium" - which is always the consequence of power.
Way three: proactive dynamics (Muscular impulse)
Next I asked Eilidh to bridge the gap between our shoulders rapidly by accelerating her body towards me rapidly. The instant she started to move she could feel the strong pressure on her left foot and the removal of pressure on the right foot. This involves a muscular impulse.
Way four: statics (Slow movement)
Eilidh was next asked to bridge the gap very slowly. This time the weight moved onto the right foot. Slow movement turns out to be almost a "constant speed" which means there is no acceleration of the CM. This has the opposite effect at the feet and skis. When a skier hesitates too much this likewise causes the force to go to the wrong foot when turning and can cause real problems. This is why a confident person can often progress in skiing much better than someone who is either timid or tied in knots through stupid instruction.
Way five: Gravity
The fifth aspect of moving the CM involves discerning what motion is caused by gravity, muscular input and the ski itself. This aspect was left until later and it did cause a little confusion - but the reasons for that will become apparent later. The point is that "toppling" over simply due to gravity is an "acceleration" and so counts as "dynamics"

Later on we have to identify how to work with the dynamics (power) and how to organise and channel it appropriately. The following "bicycle" analogy heps us to get there...

The bicycle analogy
Eilidh mentioned that even on a bicycle, when turning to the left the right leg is extended with pressure on the right pedal - and if you stand on the left pedal you fall over. Well, the mechanism of the ski and the bicycle are extremely similar - so it's not a big surprise to find that we have to do the same thing. It's this simple: The skier has one job - to fall over (laterally). The ski has one job: to bring the skier back up. A bicycle does the same thing, by changing shape in response to the rider falling to one side, the bicycle cuts under the rider's new trajectory and brings him up. At all moments the rider is in control and can decide to increase the fall or to allow the bicycle to bring him back up. Experience and practice are necessary to anticipate the mechanisms and consequences of subtle shifts of the CM necessary to control all the processes, but the primary control always involves the Centre of Mass.

First Dynamics
Best executed on gentle terrain with moderate speed (as on a bicycle) and small but definite accelerations of the CM in the appropriate direction (direction of turning). Shallow turns only - just a few degrees either direction. 
Eilidh's first attempt saw her push away her support ski to the outside of the turn, but she soon corrected this and managed to keep the skis parallel and provide a good support for her dynamics. Eilidh immediately recognised how "effortless" turning like this felt in comparison to what she had been doing up until now. 

Subtle but definite use of dynamics to control a turn

Training Response
I pointed out to Eilidh that the moment she went on something steeper she would be unable to sustain the new movement pattern because she would reflexively revert to her previous defensive and trained movement patterns. The previous training is already well absorbed and functioning partially at an unconscious level - so it can happen even without realising it. Because we were now trying to do the complete opposite this could create various different levels of conflict - both conscious and unconscious - which often imparts a strong sense of confusion. The pushing out of a ski into a plough or stem involves the use of the abductor muscles in the legs. This is basically the wrong movement pattern for skiing and the opposite is required at all levels.

Emotional Response
The CM control that we were attempting to develop, despite being completely natural -i.e. move to the left to go left etc. nevertheless initially remains extremely counter-intuitive in the context of standing on skis and accelerating on the side of an intimidating mountain. We have the ability to "learn" either by osmosis (absorbing) from copying, adapting to constraints or though conscious understanding and through this process we can apply our natural abilities to relatively unnatural situations. This process can still be somewhat personally challenging and requires that defensive reflexes be overcome or suppressed to some extent. Defensive, reflexive and emotional  acts usually involve braking or blocking actions with great levels of tension and physical resistance. This can also involve fixating a stare on the ground consequently distorting the sense of speed. It can involve a physical desensitising of the body and feeling through tension. Unfortunately standard teaching methods do not address those issues - they in fact directly play along with them - encouraging them so that the individual is not required to confront those issues on a personal level and the instructor is not required to have a brain. This makes the instructor's job easy but the more intelligent and precise the student is the worse the result will be. Those emotionally defensive acts such as the pushing out of the ski appear to be very emotionally reassuring to being with - but they lead to permanent conflict with natural movement at all future levels of development.

Cause and Effect
Proactively creating the dynamics on shallow truns and noticing the change of pressure happening under the feet due to the intentional acceleration of the CM to the side and then the skis sustaining the accelerations. The pressure change on the feet is an effect not a cause. Even where muscular impulse is involved this is only caused by our intention to move the CM and it is not our objective.

Our perceptions are largely dependent upon our understanding, training and emotional disposition. More than all of that perception involves awareness and it is a holistic, emergent quality that appears on different levels. Some forms of perception require specific orientation towards certain brain functions that can be overridden  unconsciously to the permanent detriment of the individual - such as in the ability to observe, feel, listen etc.  When all of the surrounding conditions are wrong - as in BASI (British), American, French or other national teaching systems, then perception develops in an inappropriate manner inhibiting future development at all levels. The individual directly loses the ability to visualise internally and "confusion" remains the predominant sensation at all levels.  
After the first exercise I pointed out to Eilidh that she would now be able to see (perceive) that skiers skiing by who she might have previously considered good and well above her level, were actually pushing their feet outwards and seriously limiting their performance. Prior to this new understanding this would have been invisible.

Frame of Reference
The difference between Einstein's physics and Newton's was claimed by Einstein to be due to the "frame of reference". One perception that needs to be developed in skiing regards the correct frame of reference at which the ski is operating. From the skier's point of view the ski is skidding outwards in a non-carved turn. From the ski's point of view the ski is actually being deflected inwards for a straight line at any point in the turn. As long as we pin our perception to the skier's view we get it wrong! Context is everything! With Newton's gravity we see any thrown ball travel through the air in a parabolic curve - but this is not the correct context. If we go off an Olympic ski jump and while we are travelling through the air we then throw the ball, it will move away from us in a dead straight line - exactly as perceived in outer-space. The person standing on the ground sees you and the ball go in different parabolas. Einstein's frame of reference is the correct one - that is - the straight line. When we observe the ski's behaviour from the correct frame of reference we can see what to do with it - pull inwards - work inwards - never outwards.

Mutual Exclusion Principle
The main difference in levels between skiers is that lower levels displace their feet - outwards in the turn, and higher levels displace their CM. The two are mutually exclusive - you can do one or the other. Displacing the feet towards the outside to the turn causes a loss of support. This can have a drastic effect on ice!

First Feedback
After a few attempts at dynamics Eilidh was slightly twisting her body into the turn. I pointed out that if she was on a bicycle she wouldn't do that - and that here is was equally inappropriate. In fact such twisting actually forces the CM back out of the centre of the turn.

Dynamics Demonstration
This is where I demonstrate dynamics with high speed medium radius carved turns - simply to help drum in the message clearly that it's the body that has to move. I want this to be seen and to be clearly visible though exaggeration. Now that Eilidh is aware of the issue she will be able to see it.

Dynamics in the plough
For the steeper slopes it was practical for Eilidh to retain her snowplough and simply incorporate dynamics as much as she could. Certain elements of the plough would be naturally and unconsciously positively modified simply by trying to move the body in the correct direction. Eilidh would need more time on very gentle terrain to accustom her body and reflexes to the correct accelerations and coordination. I pointed out that she might make mistakes with the dynamics due to moving too slowly or twisting the body - so she should keep an eye open for those potential errors.

No Limits
I explained that there is no limit to how proactive you can be with dynamics. On a bicycle there is a limit determined by the grip of the tyre rubber on the road. On skis the opposite happens as the ski bites more as edge angle increases and in fact the limiting factor is with just how far the skier can actually manage to fall over. Most people can only manage to "fall over" to about 20° maximum before the ski will not permit them to go further. The very best and most athletic skiers can get right down on the ground and will still recover. Bode Miller managed this in a World Cup downhill in Val d'Isère when he had his shoulder on the ground and was on the outside edge of his inside ski - at probably about 80mph - but still didn't lose it - and came right back up.

Dynamic Range
The skier's goal has to be to increase the dynamic range - to try to "fall over" more against an exponentially increasing resistance from the ski to falling over. Most people are trying to do the opposite - trying hard NOT to fall over. A complete shift in perception is necessary here.

Exercise two: sideslipping
Going sideways is a major aspect of skiing and the more comfortable someone is with this the better their skiing will be. We worked on sideslipping and the basic skills involved. first thing is to be aware of the placement of the feet - the uphill ski must be down close by the lower ski. If this uphill ski is allowed to separate and be left uphill then it will switch to it's lower edge and jam on this edge stopping the slipping action. Placement of the feet/skis is critical in sideslipping. This later leads to an understanding of why for some forms of skiing it is necessary to keep the feet quite close together.
Movement is primarily controlled with moving the CM. A very slight movement downhill is all that is required to slide and back into the hill to stop. To slide forwards (diagonally) a slight forward motin of the CM can be introduced and back to go backwards. This develops edge/feet/ski awareness and CM control.

Mountain Bike Hairpin Turns
When we turn on a bicycle most of the time we are unconscious of how the CM controls the turn, but when we negotiate a steep hairpin on a mountain-bike we have to consciously throw the bike over first then our own body - or we won't make it. Practically every turn on skis is the equivalent of this - so we need to be very proactive with dynamics - not reactive, just waiting for feedback from the skis to give us confidence. We have to dominate the process.

Building the support from the feet up
Eilidh clearly didn't have a strong base of support for her new dynamics to work. She was not aware of what to do with the feet and legs in order to stand strongly while moving the CM. To introduce this idea we attempted to do pivot turns from the uphill ski using the adductor muscles in the inside of the leg. I didn't expect her to be able to do this (but you never know) but I wanted her to start to think about the adductor muscles on the inside of the legs and to start to use them. This wouldn't be easy because it is the complete opposite of pushing the ski outwards - but we had to start somewhere. I demonstrated the pivot turn from the top edge of the top ski (as opposed to the bottom edge of the top ski used in the plough) and let Eilidh see how incredibly easily and quickly I could turn. This demonstration was intended to change her understanding of skiing - to put an idea into her head. She made a pretty good attempt at it first time round, managing the turn initiation well but not quite completing it. 
I explain that I'm not "twisting" the ski - but pulling the front down slightly just to get it to slide. This is a development directly from the side-slip. The muscle pattern is the exact opposite from the plough - pulling inwards not pushing outwards. 

Leaving the pivot behind after a few attempts I asked Eilidh to just return to the dynamics but to try to include a pull inwards with the adductor muscles.

Heel Support and the Subtalar joint
We move indoors for a relaxing drink and then to remove the boots and work on the feet. The basis of a good support comes primarily from the feet and at this stage not a great deal of awareness is necessary of the feet to get a result. I had Eilidh stand with her right boot off and with the weight distributed over her whole foot. When asked to bend the ankle would collapse. The foot with the boot still on showed how the boot would compensate for this collapse and hide the issue. It is a basic error to allow the boot to take over the support from the leg. Eilidh saw how standing with the weight on the heel caused the ankle to go strong and the anterior tibialis muscle to tighten in the outside of the shin. Instead of the ankle bending and collapsing now the body was forced to keep the ankle strong and to bend at the knees and the hips. 
From the heels it was demonstrated how the subtalar joint below the ankle could be used to rock the foot from edge to edge. With weight on the whole foot this became impossible and only the knee moved around creating a twisting action and having the exact opposite effect on the foot. I mentioned that I myself don't ski on the heels and there are other ways of achieving the same effects - but to begin with this is by far the easiest way to learn. This would also protect the knee (particularly the anterior cruciate ligament) from injury as it helped to restrict twisting movements the knee. This rocking of the subtalar joint connects up to the adductor muscles and so the support can be felt up through the entire leg - on the inside of the leg. With this support the skier can achieve good dynamics. Unfortunately any tendency to twist, steer or push out the ski will destroy this in practise. I didn't take time to show at this stage how this stance specifically relates to ski boots and how to feel the "bounce" of the front of the boot correctly. Lower level boots tend not to function correctly anyway so she might not have had the right feedback from the equipment anyway.

On returning to the slope we just added the heel stance and the adductors to the dynamics in shallow parallel turns so that Eilidh could feel the added support. I pointed out that even rocking the feet moves the centre of mass in the appropriate direction. Rock the feet onto the left edges and the CM moves to the left - both of which help you turn to the left.

Eilidh making progress on the first lesson

Exercise three: Dynamics Part Two
When a motorbike goes into a turn it drops down towards the turn centre, but to come back out of the turn it has to rise back up. This is the source or reference for "timing" in skiing. Dynamics therefore has two aspects - getting into a turn and then getting back up out of it. With a motorbike it's relatively simple because the vertical is perpendicular to the ground on a flat and level road, but in skiing, which is always on a slope, the vertical is not the same as the perpendicular. There is a break in symmetry here which complicates things - but also it's what makes skiing interesting. The turn is completed when the skier is perpendicular - not when "vertical" to gravity. This means that linking turns becomes a dynamic process using both gravity and the power of the ski bringing the skier up - (plus added muscle power from skating if required).  The truly interesting part is that instead of stopping the turn when the skier is "vertical", the skier has to actively accept "falling" due to gravity to come out to the perpendicular while still standing on the lower ski. This requires some anticipation for the following turn - so it also requires some experience to execute confidently. We worked on this second part of the dynamics for a while. I demonstrated how the turns are linked together in this manner showing how I'd stay on the  lower ski as my body started to topple out from the hill. I also explained that whether we were at the end of a turn or in a traverse it was essentially the same thing. The traverse is "vertical" and we need to get out and up to perpendicular before even thinking of starting the next turn. Continuing over into the next turn would facilitate a switch of support foot as resistance from  underneath the lower ski disappeared. Because the skis job is to bring the skier up - it will always try to get to the perpendicular. In fact it's because of this that the skier must fight with the adductor muscles and the subtalar joints and the CM towards the turn centre until it is really necessary to come out of the turn . The ski will try to pull each part of the body "out" starting from the feet upwards - but the skier should try to make sure that it's the CM being affected and not something lower down. Most skiers do not adapt to the changing geometry of the turn neither by holding their body far enough into the turn centre as forces build - nor by allowing their body to come out to the perpendicular when required at the very end of the turn.

Free Float
We need another shift in perception of gravity to perceive the "perpendicular" correctly. When sliding down a hill you do not feel "gravity" pulling you and that's because it isn't actually a force - it's a geometrical effect. When we stand on flat ground all we feel is the elastic force of the ground pushing upwards. On a slope - when sliding - we only feel a reduced percentage of that elastic force - that which is pushing up perpendicularly but depending on the angle will be a proportionally reduced percentage of the maximum force we felt when standing on the flat. If we had a slope of 90° then there would be no resistance underneath us and apart from the wind we would feel absolutely nothing - exactly as in outer space. We have entered into a new world with sliding - and we have to learn to accept and relate to this world. Our normal world requires us to reference ourselves to “vertical” all the time and this is something the skier needs to change. When children are learning they often have a lot of trouble with this and they very stubbornly keep their bodies bolt upright and vertical all the time.

Exercise four: skating (one leg)
After our afternoon break we got together for the final hour of the day to try to consolidate or move things on a little bit more. The only new thing we added was through a few skating exercises. I wanted Eilidh to understand that skiing is a “one legged” activity. Even though both legs are nearly always in contact on the ground – at the level of the hips the body must be firmly planted on one leg or the other. This is because that hip joint acts as a fulcrum through which the whole upper- body pivots freely from the lower body. If there is undue pressure on the other leg then this can’t happen and problems occur. When people push the skis outwards then they end up on two legs and their support falls apart.
I wanted Eilidh to skate across the hill stepping completely and strongly up onto the top edge of the uphill ski on each stride. This is nothing to do with “weight transfer” it is about an internal switch from one leg to the other within the body and learning to feel it in an exaggerated situation. Eilidh couldn’t yet cope with that but managed to just step uphill in the traverse. The idea was then – when totally committed to the uphill leg and standing up on it with the lower ski slightly of the ground as a result – to fall into the new turn downhill and remain standing on that leg. Unfortunately this confused Eilidh because it was so similar to moving the CM towards the outside of the turn. This is actually a preparatory move and happens before the turn. We discussed this later to remove the confusion. The idea was to get Eilidh standing much more strongly on one leg to execute more effective dynamics.

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