A READER ASKS ABOUT STATIC PRELOAD AND SR STANCE


I apologize for the delay in taking the static preload issue to the next level; application to stance. There are a number of associated issues that I need to generate graphics and animations for. In the meantime a reader asked the following questions:

“1) Am I understanding “static preload” they way you want us thinking of it? That is “static preload” is the basic optimal stance for skiing.”

COMMENT: The static preload sets up the initial angle of the shank. It provides the foundation on which to build an SR stance. A number of factors, but especially excessive Zeppa-Delta Ramp Angle and arch supports, can prevent the setting up of the static preload. It is important to understand that the static preload is established by a reflex action. It happens as a result of relaxing the hamstrings-gastrocnemius muscles and allowing the weight of the body (CoM) to stretch them.

“This stance would be then modified to accommodate the forces and demands place on the skier’s body by speed, terrain, turn shape etc. In other words, the body once it has learned this optimal stance(s) it will then use the stretch reflex to maintain optimal balance in the Coronal or frontal (for aft) and Sagittal (left right) planes regardless of terrain etc. It is this vital sensitivity element that allows as skier’s brain to actually control the edge/snow interface to effortlessly locomote on skis.”

COMMENT: The stance is configured from the static preload that configures the triceps surae (soleus-gastrocnemius) in isometric contraction. Every day when you start skiing, you need to perform what amounts to a pre ski SR check. I will explain how to do this in a future post.

“2) There is a caveat of course; the boot must be mechanically able to permit the optimal stance(s), or “static preload”. ”

COMMENT: The structures of the boot must enable the 3-dimensional global articulations of the joints of the foot associated with the optimal stance characterized by the posterior chain of muscles (soleus-gastrocnemius-hamstrings) in isometric contraction.

“3) You are suggesting that the “static preload” be a learned experienced in bare feet so that the skier’s neurologic system will recognize the sensation both in skiing and boot fitting. Modern ski boots make both more difficult.”

COMMENTS: Yes and yes. I will explain why soon.

 

5 comments

  1. David, I think you meant that I am a “dedicated” ski instructor not “decorated”? Just a comment to ski racer. We can only learn or add to our knowledge if we realize we don’t know everything. That perhaps our currently held beliefs could not be exactly correct or could even be wrong. If we are committed to increasing our knowledge, challenging the existing truth and moving forward (just look at where skiing started and where it is today) and also allowing for the fact that communication is one of the most difficult things in the world and realizing that we are all trying to progress, then and only then will we find a way to experiment, share ideas and work together for the benefit of all. The only people who don’t learn anything are those who already know everything. Or as Einstein said, the definition of insanity is “doing the same things over and over expecting different results.” May the wind be at your back, the sky blue and the powder deep!

    1. Hi Rick, good to hear from you. If you can point where I said you were a decorated ski instructor (maybe you should be decorated!) instead of dedicated, I’ll correct it.

  2. My Dear Skiracer,

    I am guessing that you did not hear the significance of the meaning and reasoning behind this post.

    I am also guessing from the tone of your post you have some frustration with the creative process which unfolding here on this blog. You seem too have a high value for clarity and a desire for things to be laid out at your feet in a clear enough manor that they can be assertively engaged by another party. It is rather common in prosecutorial rhetoric to create two sides to go after each other.

    A very different scenario was being played out between Dave and me. What I employed here was/is reflective listening and it is as the hart of restorative process generally and Restorative Circles specifically. In reflective listing the emphasis is place on gaining understanding of what the speaker has to say. I did this by reflecting back to him in my own words what I heard. Note I actually made three numbered statements not questions. The only question I asked him was, if I understood the essence of his meaning the way he wanted to be known.

    Dave responded with his comments to make sure he was heard the way he wanted to be. Now the ball is in my court to reflect back to him to see if I got it this time. Your comments short circuited, blocked, have not allowed the creative process to play out!

    I want you, Skiracer, to know that the strength of this process is evident in Dave presenting this as a post as well as a comment in “ZEPPA-DELTA ANGLE AND THE STRETCH REFLEX” https://skimoves.me/2016/10/02/zeppa-delta-angle-and-the-stretch-reflex/

    There I enjoyed the dialogue between Dave and Rick a decorated instructor. Sort of like two friends discussing this and that. And trying to understand more about how to explain optimal stance as it relates to effortless skiing and teaching. What is interesting about gaining understanding of each other’s meaning colloquially called ‘acting collaboratively’ by definition acting with good humor and precisely named ‘acting Restoratively’ because there are always conflicts; is if understanding is reached it is relatively easy to use our God given intelligence to find solutions.

    We are called Homo Sapiens, “the one who knows”. But perhaps our greatest strength is not our intellect but our ability to work together and the ability to restore connection as well as collaboration. In that light some suggest we should be called Homo Auxiliator vel Accipio Auxilium or “the one who helps or receives help”.

    Actually I am honored that Dave would perhaps unknowingly use this element of restorative process to foster scientific cooperation in order to bring better understanding to a sport we all seem to love.

    So Skiracer perhaps you could imagine what it would be like to be Homo Auxiliator vel Accipio Auxilium, thomas

  3. This post is, unfortunately, worse than any movie teaser ever produced. If you’re serious about the topic, please don’t post until you have constructive and useful info to post.

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