How do you take thee good strong recreational skiers and take them up to the next level in just 4 hours – in a blizzard?
Before…
After…
Dynamics
Step one was to introduce everyone to “Dyamics”. Abbey in particular was using a fair amount of dynamics naturally and Katie was using the least but Jackie’s earlier (warm up run) mention of burning quads revealed that she was defintiely not using the centre of mass effectively. Conscious use of dynamics (accelerating the Centre of Mass) really threw off Abbey who early on managed a complete face plant and Katie was getting stuck on her inside leg frequently and also falling over. Jackie also managed at least one fall early on. With the bad weather thrown in I fully expected all three to decide that I was some kind of nutter and throw the towel in completely – but they persisted.
All the steps used to introduce dynamics were standard and so are found on the fixed page here… http://skiinstruction.blogspot.co.uk/p/dynamics.html
When the storm eventually cleared…
Feet
I’d fully expected such tidy skiers to pick up dynamics easily but it wasn’t happening quite like that. We were forced to retire to a café to warm up and here I took the opportunity to explain how to use the feet. The first step to ensuring good dynamics is to ensure the feet are supporting the action correctly and not being used to push the skis outwards. I suitably embarassed everyone by standing up on a table in the restaurant to show the mechanics of the feet.
(The following is a straight copy from Liz and Jamie’s post yesterday – the lesson being practically identical)
- Stand on the heel (front of the heel below the ankle)
- Do not allow weght to come onto the ball of the foot when bending
- Bend at the knee and hip only – ankle stiffens by reflex
- Roll the foot onto its inside edge by using the subtaler joint
- Engage the adductor muscles on the upper leg
- Use the following formula when skiing (outside leg in the turn) – heel/edge of foot – adductors – centre of mass
- Always pulling inwards towards the turn centre (centrifugal force being an illusion – drive everything inwards)
Comparisons were made with the weak, collapsing ankle when weight is forward on the foot – resulting in leaning on the boot and the knee twisting inwards. When support is correct the anterior tibialis (shin) muscles are contracted and the ankle becomes strong – the shin making contact with the front of the boot.
Rolling the foot onto its edge causes the forefoot to turn away from the direction of the turn – not into the turn. In contrast twisting the foot into the turn forces the foot onto its outside edge – preventing the ski from functioning.
Skating
Jackie already had a natural Down/Up timing despite believing that she was doing the opposite – so she took to dynamics more easily than the others – the “inverted pendulum” effect generating timing automatically. For the others I decided to exploit skating exercises to communicate the nature of timing. Skating would serve to prevent Katie from jamming her feet together and getting caught on the outside edge of her inside ski and skating would also help Abbey to pull in her hip beneath her body and so move naturally instead of tipping her shoulders into the turns.
We began by skating across the hill and everyone demonstrated that they could skate effectively. We then had to skate off downhill into a turn and continue skating aroudn the turn. Katie improved quickly with this after a weak first attempt. Eventually we made linked turns with 3 or 4 skates in each direction – reducing to 2 and eventually 1 skate per turn. I’d already demonstrated by skating straight down the hill and then introducing dynamics that skating morphs into skiing – but the skating with the legs remains constantly active although not visile to anyone who doesn’t understand it.
The “After” video shows good active dynamics supported by skating/independent leg action - by everyone.
Pivot
We ended up with a little work on pivoting to show the second fundamental way a ski operates – with no dynamics. Dynamics requires the ski to travel forwards (like a bicycle) and this lifts up the centre of mass when it falls over. With pivoting the ski does not travel forwards – it sideslips ito a turn and the Centre of Mass is controlled by use of the pole for support. The Centre of Mass still determines the operation of the skis as they follow it into the turn.
There is a full explanation of the various pivots here… http://skiinstruction.blogspot.co.uk/p/pivot.html
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