WHY STANCE TRAINING IS ESSENTIAL


When readers click on my blog address at skimoves.me, analytics give me a hierarchy of the countries with the most views and the most popular posts in ascending order. This helps me identify which content resonates most strongly with viewers and which content draws a blank.

As I write this post, the top five countries are the US followed by Croatia, the United Kingdom, Slovakia and France.

The most viewed post today is THE SHOCKING TRUTH ABOUT POWER STRAPS; far and away the most popular post I have published to date. But the most important posts by far that I have ever written, A DEVICE TO DETERMINE OPTIMAL PERSONAL RAMP ANGLE and STANCE MUSCLE TENSIONING SEQUENCE EXERCISE barely sputtered in comparison. This strongly suggests that far from just some small gaps in the knowledge base skiing is founded on, massive craters exist.

Arguably the most important aspect of skiing is a strong stance. Any variance in the fore-aft angle of  the plane of support under the feet and the plane of the base of the ski has significant impact on stance. Yet these subjects are barely blips on the Doppler Radar of the ski industry.

Since I started the dynamic ramp angle assessment project a few weeks ago I have found that when asked to do so, it is rare for a skier of any ability to be able to assume a strong ski stance in an off the ski hill environment. Even when a skier  skis with a relatively strong stance, they seem to lack a sense of what a strong stance feels like. Because of this, they lack the ability to consciously replicate a strong stance. If asked to do so, they would be unable to coach a skier in the sequence of events that I described in my last post

In the dynamic ramp angle assessment project, I  have also observed that skiers with with a boot/binding ramp angle greater than 2.8 degrees appear to have become accustomed to the associated unstable, dysfunctional feeling and identify with it as ‘normal’. Before I can test them, I have to spend time coaching them into the correct stance because it feels unnatural to them.

When I go back and forth between a strong functional stance on a flat, hard level surface to a stance on the dynamic ramp angle device set to an angle of 4 degrees, I can get close to the same angles of ankle, knee and hip. But when I do, I feel strong tension, stiffness and even pain in my mid to lower back which is  common in some skiers and even racers.

Based on results to date with the dynamic ramp angle device, it appears as if strong skiers ski best with ramp angles close to zero. But depending on their sense of balance and athletic ability, they may have a wide range in which they sense little difference on the effect of ramp angle until they approach the upper limit of stability. While they may be able to ski well with a ramp angle close to the maximum limit of stability, ramp angles much above 1.2 to 1.5 degrees may not offer any benefits. This can only be tested on skis where balance is tested by dynamic forces which cannot be replicated in a static setting.

Issues affecting skier stance were discussed in detail in my post, THE SHOCKING TRUTH ABOUT POWER STRAPS. Here are the excerpts I posted from the chapter on The Ski Boot in the book, The Shoe in Sport (1989), published in German in 1987 as Der Schuh Im Sport– ISNB 0-8151-7814-X

“If flexion resistance stays the same over the entire range of flexion of the ski boot, the resulting flexion on the tibia will be decreased. With respect to the safety of the knee, however, this is a very poor solution. The increasing stiffness of the flexion joint of the boot decreases the ability of the ankle to compensate for the load and places the entire load on the knee”. – Biomechanical Considerations of the Ski Boot (Alpine) – Dr. E. Stussi,  Member of GOTS – Chief of Biomechanical Laboratory ETH, Zurich, Switzerland

“The shaft of the boot should provide the leg with good support, but not with great resistance for about two thirds of the possible arc, i.e., (14 degrees) 20 to 22 degrees. Up to that point, the normal, physiologic function of the ankle should not be impeded”.

“Previous misconceptions concerning its role in absorbing energy must be replaced by the realization that shaft pressure generates impulses affecting the motion patterns of the upper body, which in turn profoundly affect acceleration and balance.

“When the lateral stability of the shaft (the leg) is properly maintained, the forces acting in the sagittal direction should not be merely passive but should be the result of active muscle participation and tonic muscular tension. If muscular function is inhibited in the ankle area, greater loads will be placed on the knee”. – Kinematics of the Foot in the Ski Boot – Professor  Dr. M. Pfeiffer – Institute for the Athletic Science, University of Salzburg, Salzburg, Austria

It has been over 40 years since international authorities on sports science and safety raised red flags concerning the adverse effects of ski boots design and construction on skier stance, balance and the potential to cause or contribute to injury. It is time that their concerns were taken seriously and acted on. Research on stance and the effect of such things as zeppa and delta ramp angles is urgently needed.

 

2 comments

  1. Hi David,
    Please take heart that there are some of us out here who read much more than just the “Power Straps” post. I have printed copies of many of your posts to which I refer constantly as I try to grasp a better understanding of the essential elements and principles which you have developed and work to apply them to my set up and technique. I have tried to interest every ski shop boot fitter and other skiers I meet in your work with little success. That is their loss along with the rest of the ski industry. Intentional ignorance seems to be epidemic in the ski industry and is certainly promoted by the corporate powers.
    I find it incredible that any serious skier would not find your posts interesting enough to pursue in greater depth than just one article and I wonder if if the number of hits actually shows how much one reads when he clicks on that one title. When I click on one title it seems to have several more articles which follow on after the original. In fact, my printer could not handle the entire sequence of articles when it amounted to more than about 60 pages. I am sure that a catchy title like The Shocking Truth About…. also has an affect and could help elicit more hits on articles such as (The Shocking Truth About) “How To Learn Forefoot Load Transfer: Out of Boot” for example, (one of my personal favorites as it is a guide for how to work through boot modifications and develop proper stance and what a proper stance feels like in the boot).
    Herb Jones

    1. “I have tried to interest every ski shop boot fitter and other skiers I meet in your work with little success. That is their loss along with the rest of the ski industry. Intentional ignorance seems to be epidemic in the ski industry and is certainly promoted by the corporate powers.”

      You nailed it with the above statement. I became involved with ski boot modifications within a few years of the introduction of the rigid shell plastic ski boot. My curious nature, critical thinking and tendency to start with a clean sheet of paper approach led me to conclude that the premise on which what was a new product paradigm had never been vetted out, let alone validated in principle. I came to the same conclusion about footbeds which are rationalized on Merton Root’s neutral theory which was intended to have application in static examinations. Root never said that the foot was supposed to function in neutral. But footbed makers misrepresented Root’s theory, saw a huge global market and ran with.

      Once the entrepreneurs had a market based and a business model, they resisted anyone who questioned them. Emimence trumped evidence.

      “I am sure that a catchy title like The Shocking Truth About…. also has an affect….”
      It certainly does. If I titled a post ‘Vonn has developed a pimple her nose’ I would get 10 million hits the same day.

      I am focussing on simple devices and procedures like poured in place bootbeds to accommodate the outliers such as yourself. Comments, suggestions and requests are welcome and will be acted.

      Thank you for your comments and encouragement.

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