Tuesday, February 22, 2011

Luke

Day One

First thing in the morning the fresh snow was in good shape on the empty pistes and despite the continued snowfall and low temperatures visibility was good. The look of joy on everyone's faces made it clear that they just had to ski and leave the rest for later. Of course those conditions don't last for long and Florence was the first to be tripped up by a bump and to experience the more frustrating side of skiing. That wasn't the end of the day's frustrations which grew as the piste conditions worsened so tomorrow there should be no regrets felt at spending more time on technical development.

Video was taken near the start of the day just to record the current level of skiing and also to allow everyone to see themselves - in this case for the first time. It is usually a disappointment when you see yourself for the first time - but there is no better way to receive feedback than to use video. It's the same when you practise music - it all sounds great until you record it and play it back!

I put the "pre-coaching" video of all four skiers to the music of Evanescence - "Bring Me to Life" which is what we will try to do this week.


Luke (prior to coaching)
Luke is currently clearly the strongest skier in the family. He likes to go fast and feels that he can react to the forces generated. He has a great attitude and will really benefit from improved technique. At the moment he uses a two footed "push out" of the skis to the side accompanied with an up unweighting move and  followed by a strong downsink which uses the "push out" to brush off more speed. There is also upper body rotation and all the turns are made on the inside edge only so there is limited edge control or awareness. There is a very strong tendency to sit back and that appears to be linked to the vertical timing that is used. He says that he is "transferring weight" to the outside ski but that is not visible as he has a strong natural dynamic of his body into the turn that he is obviously not aware of. There is quite a lot of vertical movement but the timing is the wrong way round (not his fault). This movement is "reactive" because it disappears when he slows down and there are less forces involved. Tends to break at the waist with the sudden downsink- which is dangerous for the lower back.

Leonie (prior to coaching)
Loenie is quite static on the skis and has a large rotation - particularly with the right side of the body. There is very little in the way of natural dynamics and there is clearly a lot of tension. There appears to be a collapsing at the ankle and twisting inwards of the knees (dangerous to the knee joints) probably caused by twisting the foot (outside ski) into the turn. Limited edge control and awareness. Posture not ideal for protecting the lower back - elbows too far back and lower back hollowed.

Florence (prior to coaching)
Florence is currently very static because she has a strong "push out" and bracing against the outside leg  (slight stem sometimes) and rushes the start of each turn with an upper body rotation. This would cause anyone to feel insecure on skis and to become very tense. She is clearly twisting the feet to steer the skis which brings her (outside) knee inwards despite the bracing of the leg. She gets away with all of this because she doesn't use the inside edge of the outside ski to start the turn - but she has no awareness of such edge control issues yet. Posture OK but arm carriage poor - hands dropped by the side of the body.

Ella (prior to coaching)
Strong heel push (to the outside) and clear weight transfer to the outside ski. - very static. This looks unstable and is ineffective. Posture and stance look good.

Introduction to Dynamics
Indoors, over hot chocolates I gave a brief introductory explanation of "dynamics" and about changing the intention from "balance" to "falling over".
Back on the slopes everyone went though the "pushing against the wall with the shoulder" exercises prior to attempting to use dynamics on skis. This allows everyone to feel what shape the body takes and the same forces through the legs that will be generated during actual dynamics.
We then went on to linking turns and eventually skiing with dynamics. Everybody got the idea but Ella caught on both the quickest and clearest reporting immediately how much easier it made her skiing. She did look like a completely different skier right away. Luke also looked completely different when he stood up and stopped the inappropriate vertical movements. I explained that timing had to come from the dynamics - down into a turn and back up out. Also pressure changes under the feet have to come from dynamics - they are all "effects" and not "causes". 

Day Two

Feet
Day two started early at 08:30 with an indoors session about the feet. This is a fairly big subject in its own right. Without wasting any time it still took an hour to cover the essentials. We had a look at the right thing to do with the feet and also the wrong things - because it is important to be able to recognise both right and wrong. 
  • The major error is to collapse the ankle by trying to press down on the ball of the foot. This causes the boot to take over the support of the body instead of the actual leg. This also makes it impossible to roll the foot onto its edges and instead causes any attempt to do so to turn into a twisting at the knee - which can lead directly to a broken anterior cruciate ligament.  
  • The above error is linked to the coordination taught in a snowplough - where the abductor muscles are used to push the leg outwards away from the body, causing the foot to twist inwards and to flatten (roll slightly onto its outside edge.
  • This error is often compounded by misaligned ski boots - where the angle of the foot of the boot is not adjusted correctly to keep the base at right angles to the hip joint. This can only be tested with an unloaded leg locked out straight - not as is always done in shops with the client standing up and flexing in the boot. Shops fail to separate issues of pronating feet, and other biomechanical issues from the simple matching if the exoskeleton ski boot to the actual skeleton of the leg.
  • Correct stance is most simply achieved by standing on the heels. This causes bending to occur at the knees and hips only and tightens the anterior tibialis (muscle running up the outside of the shin). The ankle becomes strong. Weight does not go backwards doing this. When bending in the ski boot there should be no contact of the leg with the shaft of the boot - no leaning against the boot. The ankle naturally locks at an angle of about 12° corresponding to ski boot design. 
  • Standing on the heels permits rocking laterally of the feet onto their edges using the sub-talar joints below the ankles. (This cannot be easily achieved with the weight on any other part of the foot.) Rocking the feet to the left corresponds to rocking the skis onto the left edges and holding them there. This also corresponds to a motion of the Centre of Mass (CM) to the left and this can be felt as the body re-centres over the edges of the feet.
  • Rocking the feet to the left also corresponds to the adductor muscles in the right leg tensing up. This "pulling in" of the adductor muscles is a very important aspect of skiing as it is the basis of correct coordination - contrary to the "pushing out" and abductor use taught in the infamous "snowplough".
  • I explained how the ball of the foot can be used instead of the heel - with the heel actually lifted up slightly and the support coming from the muscles in the foot being active. This can be of great help for people with very unstable ankles but generally it is best avoided at an early stage. It can take years to train the muscles in the foot and to develop enough awareness and flexibility in that area. To achieve this however all you need to do is place the foot on the ground on its outside edge then, holding it like that stretch the ball of the foot partially towards the ground and when the stretch is as great as it can be then take the foot off its outside edge to let the ball touch the ground. Retain all the muscle tension because that is what generates the arches and support of the feet when standing up on the ball of the foot. Rocking on the edges can still be achieved in this stance and the ankle is very strong. This does give a superior control and feel over the ski and is eventually preferable to the heel use. I have however completely worn though the heels of inner boots from using the heels so this will do for much of the development for most skiers.
  • I demonstrated how to test the effective response of a ski boot using the stance on the heel - bending the  knee and hip to 90° and then bouncing off the front of the boot. In Luke's case his boots just collapsed because they are poor quality beginner's boots.
On the mountain everybody tried immediately to combine the rolling of the feet from the heels with the dynamics of the Centre of Mass.  Luke immediately found that this helped the dynamics make more sense for him.

Introducing Skating
It was becoming clear to me that Luke's tendency to be back in his ski boots was due to his two footed heel push. Leaning slightly backwards gave him more purchase for pushing the heels outwards. To deal with the two issues - leaning backwards and and pushing outwards of the heels I had him attempt to start the turn from a traverse on the uphill edge of the uphill ski - just moving the CM downhill to start and control the turn. This puts the skier on one leg and being on the uphill edge it stops any pushing outwards - the CM is forced to move instead. Standing on one leg also causes the reflexes to move the body perpendicular to the slope.

The next exercise was to step up the hill and stand up cleanly on the uphill ski, uphill edge. This is simply an exaggerated side stepping uphill. When done with forward motion at the same time this is much more difficult and I asked everyone to try to do this between turns then to remain standing up n the uphill edge of the top ski in preparation for the next turn. This action of stepping up is exactly like skating. Due to bad weather I cut the progression short and simply skated downhill introducing more dynamics until the skating turned into skiing and asked everyone to copy this. There was a reasonable amount of success first time at feeling the skating rhythm with Ella being the most natural on the first attempt. On subsequent attempts Leonie connected better with her skating experience. Everyone felt the skating timing to some extent.

I asked everyone to observe that with only dynamics being used the pressure cycle they would feel would be exactly like skating. The same "down/up" cycle exists in both dynamics and skating.

Introducing Pivoting
In order to continue to work against the tendencies to "push out" I decided to waste no time in introducing pivoting - which relies strongly on "pulling inwards" with the adductor muscles. We worked on the uphill ski pivot. To help to establish the correct use of the adductor muscles I had everyone pull the inside edge of the  tip of one ski against a ski pole. Nearly everyone found the heel going outwards instead of pulling inwards which means their perception of "adductor" use still meant twisting instead of a simple pulling inwards. With this corrected everyone worked on pivoting for a while and there was a reasonable amount of progress.  We also spent a short time working on the lower ski pivot. Leonie started to feel how much the body had to move into the turn for this to work. The aim here is really to develop the understanding of the relationship between CM and edge control. It was pointed out that pole planting is an essential component of pivoting because the pole support permits the CM to move downhill without the skis changing edge. This is a tricky skill to develop. The pivoting was then used briefly in powder snow on a shallow gradient along with some dynamics.

Pivoting is used for short turns and fall line skiing where the body does not travel across the hill and speed control is important. I pointed out that the skis must remain downhill of the skier's CM  and that this is why it is best achieved with the feet together. Placing the feet apart changes the edge of the uphill ski to the inside edge and to pivot we must start the turn from the outside edge. At the start of the turn it is best to see the inside edge as an accelerator and the outside edge as a brake. Longer turns started from the uphill edges can also reduce tiredness as less force ends up going through the legs in general. Inside edge skiing is much more powerful but can't be sustained so effectively.

Upper Lower Body Separation
After lunch the weather had deteriorated even more so we did our best to continue to focus on technique. Luke asked which direction the body should face during a turn and said that he was confused over this issue. Leonie had a strong rotation that caused her trouble at the end of turns on more difficult terrain so to deal with both Leonie and Luke it was time to introduce Upper / Lower Body separation ("U/L" for short). I explained that dynamics was best learned by just following the skis and keeping everything as simple as possible. Fall line skiing with short turns however requires that only the legs turn in the hip sockets and the upper body is prevented from turning. There are several good reasons for this but the mechanical action at root is based on skating - and being able to hold the body down and into the centre of the turn correctly as the turn progresses. I had earlier shown Leonie how when side-slipping, if she turned her bottom to face uphill she could hold the ski on edge and stop, but as soon as the bottom turned downhill she would slide. The same thing happens with rotation - the bottom goes out, the CM goes out and control is lost. I did the "pulling downhill" with ski poles so that both skiers could feel the difference in strength with each stance. We then removed the skis and I showed how the legs could rotate independently in the hip sockets. Luke amusingly had trouble coordinating this. We repeated the exercise by jumping. Leonie started to get the message about rotation and managed to remove it from her skiing both at the start and end of the turns. This led to a successful and controlled descent down a steep icy run back into Val at the end of the day. Luke realised that he was glad to be working on his skiing because he was starting to see just how far his technique had been off the mark and that just continuing to blast around with such poor technique would be getting him nowhere. He could now start to recognise the faults and limitations in other skiers around him as his perception was changing. You literally only see what you understand - that's how visual perception works.

Leonie and Luke's wine...




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