Avni had one run to warm up and get used to sliding after a 2 year break from skiing. It usually takes a couple of hours to really tune in again but we didn’t have that luxury. However, by the end of the first descent Avni was looking more relaxed and I’d had the opportunity to observe her movement patterns properly.
The video shows Avni before starting to make changes – one exercise on dynamics - and then skiing towards the end of the session.
Preparation
Watching and listening to Avni made it clear that her understanding and execution conformed pretty much exactly to classic ski instruction doctrine. “Pressuring the ski” meant placing the body over that ski, almost painful pressure on the shins involved flexing the ankles and knees, “facing downhill” resulted in unwanted whole body rotation and/or stemming, the up/down and pole plant turn configuration was harsh and unstable. No wonder Avni didn’t have the confidence to go fast – I’d feel pretty much the same doing all of that! The ski boots were clearly not suitable because she had no grip even standing still – but she wasn’t aware of this being an issue. The feet weren’t being used either – something critical even at a basic level.
Had I been applying standard ski instruction all of those things would be identified as caused by the skier and I’d set about “correcting the problems being caused” – when in reality they are all caused by the teaching – every single one of them!
It was from listening to Avni that made me decide to begin the lesson with Dynamics.
Whole body rotation – (when trying to face downhill) Stemming as right ski tail skids out (largely due to feet/legs)
Dynamics
Our dynamics session followed my standard procedure – detailed here http://skiinstruction.blogspot.com/p/dynamics.html The menu at the top of this page has a tab for the same location “Dynamics”.
Standard ski instruction teaches people to be in “balance” keeping their weight between their feet or skis. “Pressuring” the ski in this scenario means moving the body centre (centre of mass COM) over that ski – left ski means move the body to the left. In physics this is “statics” and it’s only one of two different ways to “pressure” but unfortunately it’s the wrong one and I knew from her skiing and verifying with questions that this is what Avni was doing.
The other way to “pressure” your left foot or ski is to use it to accelerate your body to the right – with all the emphasis on ACCELERATE. This is Newton’s second law F=Ma (force equals mass times acceleration) and the force at the foot is generated by accelerating the (COM) mass away from it – which in this case is towards the inside of a turn.
During the explanation we carried out static exercises with Avni leaning and pushing against me – then on to progressively building this into turns when moving.
The skis work the same way as a bike – you fall over and the bike changes shape and cuts a new trajectory in front of your COM and lifts you back up – but you MUST fall over for this to happen and you MUST have some speed. Skiing is absolutely not about balance – it is about dynamics.
Within a short time Avni was linking turns and remarking how it was much smoother, easier on the legs and no pole plant was required – all correct observations. She also realised we weren’t even trying to face downhill – which – as on a bike – is not appropriate. Later on we will employ such things – including pole use – but nothing like the way they are learned in conventional instruction. Just watch all the ex racer French instructors follow their skis – when skiing with clients – never “facing downhill”!
Pole Use / Timing
The skier is like an inverted pendulum – as is a motorbike going around a corner – tilting over and down into the turn and coming back up at the end. Stability is generated naturally with this down/up timing and skis are manufactured to work specifically with this – and have been so since the late 1960s. When using dynamics like this there is simply no need for a pole plant as you are up high between the turns – not crouched down stabbing the pole into the ground! The stability and feedback come from the skis and legs doing the job properly!
Boots/Feet/Adductors
I have a special way of rapidly checking ski boot alignment and skier morphology – something that took years of experimentation but eventually came to me in a moment of insight. We used this indoors and could see that Avni’s boots were significantly under-edged which made it hard for her to grip well and then mover her centre of mass from a good support. We will need to address this in the morning before the next session.
We worked on how to use the muscles and bone structure on the feet, and legs. First of all it was clear that Avni was flexing her ankle when bending and collapsing her weight onto the front of the ski boot – which means that her leg was not supporting her properly. This is initially overcome by standing on the front of the heel beneath the ankle joint and maintaining the stance there when flexing – causing the anterior tibialis (outside muscle front of shin) to contract and stabilise the ankle and foot. Bending is now at the hip and knee instead of the ankle and knee.
Standing on the heel the subtaler joint – between the ankle and heel - can be used to rock the foot onto its inside edge. This won’t happen if the ankle collapses and the foot collapses. Rocking onto the inside edge of the foot causes the leg to pull inwards slightly laterally and activates the adductor muscles on the inside of the leg – securing the knee.
Bringing it all together
- Rock the foot
- Engage the adductors
- Move the Centre of Mass
Sideslipping
When sideslipping keep both feet rocked onto their inside edges. The uphill ski will remain on its uphill edge despite the weight going onto the lower edge (inside edge) of the foot – it’s the ski boot shaft that provides the lateral stability to permit this – hence good alignment is required.
Early commitment to the new turning ski
Similar to the sideslip use the uphill edge of the uphill ski to stand early on the uphill ski to “push " yourself into the dynamics for the new turn. This completely prevents any tendency to stem or hesitate with dynamics and gives a solid turning platform. You don’t have to change onto the inside edge of the new turning ski to be able to initiate a turn!
Video
By the end of the session the visual impression for any onlooker is that the skiing is much smoother and secure, no harsh up/down/pole issues and snatching the turns, no real stemming or significant body rotation. Very good progress for one session!
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