Thursday, April 6, 2017

James, Liz, David

James had recovered from his gastro and was raring to go again but today David would have priority. It helps if everyone is on the same page with ideas and goals. The session would evolve in four distinct sections with dynamics taking centre stage. With David being an experienced skier we could go straight on to the second part of dynamics – which although not ideal for him so early on would be important for both Liz and James. Liz tends to rush the start of the turn to get the skis downhill beneath her – instead of getting the body downhill of the skis and trusting them. James does something similar but taking too long with the turn initiation and then rushing the end of the turn. Working on both the start and end of the turn with their components of dynamics should sort out both issues.

  1. Video Scene: David skiing his original “Vertical” style (but throwing in a couple of dynamic turns anyway!)
  2. Video Scene: David using dynamics – both into and out of the turn
  3. Video Scene: Liz using dynamics – both into and out of the turn
  4. Video Scene: James using dynamics – both into and out of the turn

 

 

Dynamics Part 1

http://skiinstruction.blogspot.fr/p/dynamics.html – this is the link to the fixed dynamics page. All the explanations and exercises were the same as described on the previous posts for James.

Perpendicularity was a key issue for David so time was taken to explain it thoroughly. The Centre of Mass falling into the turn places the body automatically perpendicular to the skis as they point down the slope – without the need to “lean forwards”. We aim to exploit the “free float” nature of sliding by relating to the skis and slope exactly as we do when the skis are horizontal across the hill and we are standing vertical – the common quality being “perpendicularity”.

Davd has not been “leaning back” he has been locked into the vertical plane (relative to gravity) due to moving the centre of mass outwards (not down the hill) and also by coming “up” to start the turn and losing all stability and pressure from the skis. Coming “up and outwards” will always force a skier into the vertical as the skis plunge downhill. When David worked directly on moving the Centre of Mass downhill he produced an even better perpendicularity than in the video clip where he was working on both aspects of Dynamics (slightly prematurely).

James also tends to be a bit vertical and on the backs of the boots but for him I would have other ways to deal with this. He needs to learn to feel the fronts of the skis and this is a separate issue. He is however using dynamcis and working hard at it – being a bit thwarted by his rotational habits for the moment. Practise with dynamics will help to eliminate the rotation. He is determined and has a great attitude to the challenges that skiing brings to us all – both physically and emotionally.

 

Dynamics Part 2

Exiting the turn is even more important than entering the turn. When linking two turns the first is not completed until the body is in “neutral” going across the slope. Neutral is when the skis are flat and the body perpendicular to the slope – but side on to the fall line. This position is only sustainable for a fraction of a second as the body is already beyond the vertical and is now being pulled laterally downhill by gravity. Turns are connected and rhythm established by this active movement – using the lifting force of the ski when pressure is at the maximum at the end of the turn. The lifting force keeps the body stable through this turning transition phase.

We carried out an exercise where I stood downhill and pulled each skier over their downhill leg and ski then asked them to change support leg when they were able to push against me. “Hanger” turns were then demonstrated to show an exaggerated version of this movement.

Transitioning a turn this way allows early edge pressure and grip – rounding and smoothing out the start of each turn – especially important for Liz at this stage.

 

Pivoting – Outside Ski

http://skiinstruction.blogspot.fr/p/dynamics.html

Standard practise for pivoting. Always use the inside of the foot and adductors on the supporting leg – or both legs for a two footed pivot with the skis close together. The muscle tension is not to “pull” the skis by force it is to make the body one coherent unit so that the Centre of Mass can pull the skis into the turn –but the Centre of Mass is now controlled and supported in its lateral motion by the ski pole and not by lifting power from the skis.  The skis sideslip into each turn with minimal forward motion.

 

Skating

I was keen to introduce skating at this point because the down/up timing of skating reinforces the down/up timing of dynamics (inverted pendulum) – and this resonates with the lifting power of the skis. Resonance is an amplification of an effect and often this leads to a skier becoming airborne as a result between turns. The aim here though is just to reinforce the correct fundamental movement pattern, get the legs working independently and functionally and cultivate rhythm based on active movement and feedback.

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