Wednesday, March 15, 2017

Katariina 2

Today’s session began with a warm up and brief revision of yesterday’s dynamics. The idea was to focus on the Centre of Mass and execute things in the following order…

  1. Move Centre downhill into the turn - a combination of using gravity and muscular impulses
  2. Pull the outside hip backwards slightly to align the femur and activate the adductor muscles
  3. Roll the foot onto its inside edge
  4. Ensure pressure on the front of the heel – strong ankle

Katariina expressed her need for more control on steeps, ice and bumps. Improved dynamics is the key to most of this so this would be our target for today. Skating aspects and pivoting skills are also really important – but most benefit would be taken from taking the dynamics forward at this stage.

  • Video clip 1 – full dynamics
  • Video clip 2 – Working the turn on the steeps
  • Video clip 3 – Foot forward technique – (derived from skating) – natural angulation

 

Perpendicularity

Katariina’s default way of skiing is currently based on looking at the mountain as “uphill” and “downhill”. She faces downhill and tries to get into a new turn by quickly getting the skis around the first part and back down beneath her to brake sideways. This all has to change and the first stage is to begin to understand “perpendicularity”.

When we ski on the flat or across a hill the skis are horizontal to gravity and the body vertical – while being perpendicular to both skis and the ground. When the skis turn off downhill they are no longer horizontal – but the body must be adjusted to remain perpendicular to the ground and the skis. Some of gravity now accelerates us downhill and most of it still pulls us directly into the ground and overall we should feel no difference standing perpendicular to the skis either across the hill or sliding downhill. We can relax and start to eliminate the fear of “uphill and downhill” and just see the slope as “flat” – with motion of the centre of mass lateral to the skis being the critical action we need to exploit.

The aim is to get the ski to grip from the very start of a new turn and not to rush the start of the turn. Perpendicularity is a basic principle of dynamics.

 

End of Turn Dynamics

Katariina took quite some time to get her head around this issue! She just couldn’t see it initially – but did get it in the end. There are two parts to dynamics – falling into a turn – then getting back out of the turn. So far we had only worked on part one. A motorbike falls into a turn but has to come back up out of the turn exactly like a skier. The end of the turn is where this happens. Pressure builds up on the outside ski as it crosses the fall line and then resists gravity and so as the turn develops the pressure becomes much greater and this means the lifting up power of the ski is greater. When the turn is nearing completion the skier then uses this pressure and lifting power to let the ski lift the body out of the turn right over beyond the vertical into the perpendicular – with the skis flat on the snow as they travel across the hill. This momentary position is called “neutral”. The body then continues to fall from there downhill into the next turn and the support leg switches spontaneously and naturally. The turn transition all the way to perpendicular is carried out on the downhil ski.

I demonstrated “Hanger Turns” executing exaggerated full transitions on the downhill ski with the other ski visibly held in the air – entering the next turn each time still on the downhill ski – as is seen commonly with giant slalom racing at high speed. Katariina still couldn’t recognise what was going on so I then skied linked pivoted turns on one ski so that it was really clear that the body was going over downhill ski particularly when it was the right ski and I was turning to the right on it. It was after this that Katariina seemed to get it.

End of Turn Dynamics is critical to bring skiing with dynamics into the perpendicular and to allow flow from one trun to the next without skidding and braking.

 

Working the Turn

Speed control and grip come from using the skis all the way through the turn – from beginning to end. Speed is controlled by “line” and direction – not by braking. This is normally learned through racing development. Race courses are set to very strict rules – with rhythms, breaking of rhythm and gate spacing to control speed. Good siers ski faster but over slower lines.

Part of Katariina’s probelem with this part of dynamics was that she was not driving her Centre of Mass into the turn after initiating it. The Centre of Mass must be forced in towards the centre actively until there is enough pressure at the end to fully control direction and speed – then this solid platform on the downhill ski is used as a support to lift up and out of the turn. Without that support the turn is not “worked” or developed and there is no platform for directing the centre of mass – no way to support the body coming over the downhill ski and no way to get confidently into the next turn.

When Katariina understood all of this she was able to work at controlling her speed by using both parts of dynamics on a steep black slope – video clip 2.

 

Foot Forward Technique

The video clip of the “foot forward” technique is fairly self-explanatory. This action tightens the turn radius when combined with dynamics and it improves angulation – which is naturally derived from skating – thus making tighter turns and grip more efficient on steeper terrain.  When terrain is very steep and dynamics have to be quite big then a more rapid pushing forwards of the foot ensures a more powerful and rapid turn. The combination of dynamics and pushing the foot forwards is how we alter turn radius (when not pivoting!)

We didn’t have time to go through pivoting because the dynamics had taken a bit longer that expected – but this was clearly useful and necessary. For bumps the key lies really with two footed pivoting – and the dynamcis are controlled through the use of a pole plant for the most part.

Most skiing is a blend of pivoting and dynamcis – bumps and carving being at the opposite extremes of each.

 

Mindful – Functional Skiing

Working the turn, building and using the forces and developing the “line” – with conscious understanding of the principles – are key parts fo functional and mindful skiing. All of this is governed by directing the Centre of Mass and being aware of it – like the gymnast spinning or rolling around it. In skiing we use it more like the point of a pencil – drawing our line in 3D space.

 

Mont Blanc 4810m (Seen from Val d’Isère)

 

 

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