MA Practice, Advanced

Discussion in 'Ski School' started by David Chan, May 22, 2019.

  1. David Chan

    David Chan getting after it! Instructor

    Joined:
    Nov 13, 2015
    Posts:
    107
    Location:
    San Francisco, CA
    This is in the Race course at Squaw, Shirley Lake, Skiers far right



    Spring firm, (salted) with loose spring corn over the top. Medium steep.

    Task, just trying to keep edge angles equal, changed to different sized turns after passed camera person. (Medium turns at top, shmedium turns at the bottom. (was trying to evaluate boot cants)

    Skier is advanced Male.

    Again not looking for corrections, just objective "what's going on?, Snow, ski interaction, body performance, which joints, etc..
     
  2. Mike King

    Mike King AKA Habacomike Instructor

    Joined:
    Nov 13, 2015
    Posts:
    1,658
    Location:
    Louisville CO/Aspen Snowmass
    I'll give it a go.

    In the initiation of the turn, both skis begin rotating simultaneously, with the rate accelerating from the middle phase of initiation to a constant rate through the middle of the finish of the turn, where the rate of rotation decelerates. The skis are turning under a stable upper body because the femurs are turning under the pelvis.

    From the initiation of the turn, both skis tip simultaneously so that the edge angle is progressively increased through the late shaping/early finish of the turn. Maximum edge angle is maintained through the middle of the finish of the turn, at which both skis rapidly untip. The body performance that results in this ski performance is as follows. In the late finish of the turn, there is a rapid extension of the old inside leg which pushes the pelvis up and toward the inside of the new turn with the result that the legs untip and unedge both skis. From finitiation through the middle/late shaping, the inside leg flexes, allowing the hip to move inside and down, and tipping the legs to create the edge angle. As a result of these flexion and extension movements, the primary result is inclination in the early part of the turn, but as the outside leg slightly flexes in the early finish of the turn, a bit of angulation (more so on the right turn than the left) develops.

    In the initiation of the turn, the CoM moves forward on the skis so that the pressure point is slightly aft of center. From the middle shaping to the early shaping phase of the turn, the CoM moves aft. The body performance leading to this is that the ankles are significantly dorsiflexed and generally remain in that position, yet the hip remains relatively open -- the angle of the lower leg is more acute than that of the spine. As the new outside leg extends in the late finish/early initiation of the turn, the movement is to open the knee and the hip, which has the effect of moving the CoM forward, but because the hip is more open than the knee, the CoM remains slightly aft relative to the BoS. The outside leg slightly flexes in the late shaping/finish of the turn by flexing the knee while leaving the hip more open than the ankle, with the result that the CoM moves aft relative to the BoS.

    Pressure is rapidly transferred to the new outside foot at or slightly after edge change by stepping onto the new outside ski and flexing the new inside ski.

    In the initiation phase of the turn, the pelvis is moving inside the turn and away from the skis. As a result, maximum pressure comes in the middle to late stages of the finish of the turn.
     
  3. Thread Starter
    TS
    David Chan

    David Chan getting after it! Instructor

    Joined:
    Nov 13, 2015
    Posts:
    107
    Location:
    San Francisco, CA
    I should have asked people to post where in their cert journey they are. This helps with feedback and understanding of where we should expect their level of understanding is. @Mike King , IIRC you are L2 on the the path to L3? RM division. I don't recall the format of their exams but do you have to pass skiing before MA and Teach? or can they all be taken concurrently and you retain the portions of the exam that you pass?

    Going through your MA now..
     
  4. Thread Starter
    TS
    David Chan

    David Chan getting after it! Instructor

    Joined:
    Nov 13, 2015
    Posts:
    107
    Location:
    San Francisco, CA
    By the way, If there are L3's trainers and examiners that want to give feedback to the MA given, or pose questions, that's fine too. I would learn a lot from how other's ask for clarification or check for understanding!
     
  5. Thread Starter
    TS
    David Chan

    David Chan getting after it! Instructor

    Joined:
    Nov 13, 2015
    Posts:
    107
    Location:
    San Francisco, CA
    Mike King post: 362265, said, I'll give it a go.

    In the initiation of the turn, both skis begin rotating simultaneously, with the rate accelerating from the middle phase of initiation to a constant rate through the middle of the finish of the turn, where the rate of rotation decelerates. The skis are turning under a stable upper body because the femurs are turning under the pelvis.

    Would you say that the rotary initiation is a result of active steering or something else, and if so, where are the forces coming from?

    From the initiation of the turn, both skis tip simultaneously so that the edge angle is progressively increased through the late shaping/early finish of the turn. Maximum edge angle is maintained through the middle of the finish of the turn, at which both skis rapidly untip. The body performance that results in this ski performance is as follows. In the late finish of the turn, there is a rapid extension of the old inside leg which pushes the pelvis up and toward the inside of the new turn with the result that the legs untip and unedge both skis. From finitiation through the middle/late shaping, the inside leg flexes, allowing the hip to move inside and down, and tipping the legs to create the edge angle. As a result of these flexion and extension movements, the primary result is inclination in the early part of the turn, but as the outside leg slightly flexes in the early finish of the turn, a bit of angulation (more so on the right turn than the left) develops.

    Would you consider the DIRT to be appropriate for the type of turn type and shape. Which joint/s seem most active in this tipping/untipping?

    In the initiation of the turn, the CoM moves forward on the skis so that the pressure point is slightly aft of center. From the middle shaping to the early shaping phase of the turn, the CoM moves aft. The body performance leading to this is that the ankles are significantly dorsiflexed and generally remain in that position, yet the hip remains relatively open -- the angle of the lower leg is more acute than that of the spine. As the new outside leg extends in the late finish/early initiation of the turn, the movement is to open the knee and the hip, which has the effect of moving the CoM forward, but because the hip is more open than the knee, the CoM remains slightly aft relative to the BoS. The outside leg slightly flexes in the late shaping/finish of the turn by flexing the knee while leaving the hip more open than the ankle, with the result that the CoM moves aft relative to the BoS.

    Where on the ski would you place the pressure point in these turns and how does that affect the ski snow interaction, what part of the ski is bending more? How might an equipment (boot setup) change make a difference?

    Pressure is rapidly transferred to the new outside foot at or slightly after edge change by stepping onto the new outside ski and flexing the new inside ski.

    In the initiation phase of the turn, the pelvis is moving inside the turn and away from the skis. As a result, maximum pressure comes in the middle to late stages of the finish of the turn.
     


  6. geepers

    geepers Out on the slopes Skier

    Joined:
    May 12, 2018
    Posts:
    797
    Location:
    Australia
    Currently CSIA L2 and working to L3. Passed the L3 Skiing component in March 2019. Still trying for the L3 Teaching component. CSIA is a 4 level system. I have not worked as instructor so extremely limited instruction time hence the interest in MA practice.

    Use of all joints to maintain balance? Mobile to a degree in the main joints (ankles /knees / hips) however has a tendency to be forward on the outside ski below the fall line leading to wash-out of the ski tails. (Most noticeable on turns to the left and not withstanding the momentary loss of balance aft after skiing below the camera.) The wash-out results in over-flexing at the hips and affects the transition with a tendency to remain over-flexed at the hips.

    Turning lead with lower body and ski design? Turning is led with the lower body through tipping of the skis. The turns are linked with ski tips constantly changing directions with no real tendency to traverse between turns. Both skis are tipped simultaneously and shins remain predominantly parallel throughout turns. Edge angle increases from transition to just below the fall line.

    Upper and lower body separation providing angulation? The upper body is mainly stable through the run except for the issues noted above. Angulation begins with lower legs at the top of the turn. Separation leading to hip angulation is built and then maintained throughout the turn. Pressure is directed to the outside ski above and into the fall line. Edge and platform angle should be adequate to maintain grip except for the tendency for loss of grip due to fore/aft balance noted above.

    Co-ordinated movement patterns? Some appropriate flexing and extending of ankles / knees / hips especially early in the run. Poles are also used in the 1st few turns however use decreases approaching the camera with the tendency to over-flex the hips.
     
  7. Mike King

    Mike King AKA Habacomike Instructor

    Joined:
    Nov 13, 2015
    Posts:
    1,658
    Location:
    Louisville CO/Aspen Snowmass
    PSIA-RM 2, probably terminal as I'm old, out of shape, and injured.
     
  8. Thread Starter
    TS
    David Chan

    David Chan getting after it! Instructor

    Joined:
    Nov 13, 2015
    Posts:
    107
    Location:
    San Francisco, CA
    Old is just a state of mind. Out of shape can be fixed. Hopefully your injury is healing quickly! so you can get back in shape.

    David
     
  9. Mike King

    Mike King AKA Habacomike Instructor

    Joined:
    Nov 13, 2015
    Posts:
    1,658
    Location:
    Louisville CO/Aspen Snowmass
    Answers to follow-up below.

    In the initiation of the turn, both skis begin rotating simultaneously, with the rate accelerating from the middle phase of initiation to a constant rate through the middle of the finish of the turn, where the rate of rotation decelerates. The skis are turning under a stable upper body because the femurs are turning under the pelvis.

    Would you say that the rotary initiation is a result of active steering or something else, and if so, where are the forces coming from?

    I believe the rotary is coming from the skis being placed on edge and bending, which results in the skis assuming a rotation.

    From the initiation of the turn, both skis tip simultaneously so that the edge angle is progressively increased through the late shaping/early finish of the turn. Maximum edge angle is maintained through the middle of the finish of the turn, at which both skis rapidly untip. The body performance that results in this ski performance is as follows. In the late finish of the turn, there is a rapid extension of the old inside leg which pushes the pelvis up and toward the inside of the new turn with the result that the legs untip and unedge both skis. From finitiation through the middle/late shaping, the inside leg flexes, allowing the hip to move inside and down, and tipping the legs to create the edge angle. As a result of these flexion and extension movements, the primary result is inclination in the early part of the turn, but as the outside leg slightly flexes in the early finish of the turn, a bit of angulation (more so on the right turn than the left) develops.

    Would you consider the DIRT to be appropriate for the type of turn type and shape. Which joint/s seem most active in this tipping/untipping?

    The DIRT is appropriate for this type of turn type and shape. The joints most involved in the tipping are the knee and hip. From a prescription of change, and more ideal process would be to tip and untip from the lower leg so that the lower body leads more into the turn. Because the extension move of the old inside leg starts the pelvis to lead inside in the turn, the upper body dips inside early in the initiation of the turn. By having the upper body travel more with the skis in the initiation of the turn and tipping the lower leg (by flexing the old outside leg to release and rotating the femurs to untip then tip the lower legs), a platform would be established early in initiation that can accept the pressure of the turn.

    Where on the ski would you place the pressure point in these turns and how does that affect the ski snow interaction, what part of the ski is bending more? How might an equipment (boot setup) change make a difference?

    In general, I believe the pressure point is mainly behind (aft) of the bindings. The result of being aft is that the skier has the temptation to create higher edge by pushing the skis away from the body in the late shaping and early finish of the turn with the resulting loss of balance in the right footed turn where the push was too great for the resistance of the snow. It appears to me that the skier is over pressuring the front of the boot. I'd suggest a gas pedal to see if that would allow the skier to open the ankle and have a shin angle that better matched the angle of his spine. Other boot adjustments might include moving the power strap inside the upper buckle of the boot to pull the shin off of the tongue of the boot and better seat the heel in the boot.
     
  10. Mike King

    Mike King AKA Habacomike Instructor

    Joined:
    Nov 13, 2015
    Posts:
    1,658
    Location:
    Louisville CO/Aspen Snowmass
    Working on the out of shape. The real issue is that the Level 3 standard is very high and requires mastery of a lot of tasks that I may no longer have the athleticism to achieve. Rocky Mountain is changing the exam this coming season so that you have to pass all of the ski exam in one go. If I had not had my season curtailed this year, I intended to take the ski exam so that I might pass one component and bank the opportunity to work on the fails in isolation. Now it looks to be an almost insurmountable objective. So, I'm vacillating in whether to give up or continue to work on it. I really don't care about the MA and teaching components, as this was always about achieving a standard of performance in my own skiing.

    Mike
     
  11. Thread Starter
    TS
    David Chan

    David Chan getting after it! Instructor

    Joined:
    Nov 13, 2015
    Posts:
    107
    Location:
    San Francisco, CA
    Hmm. Sounds like RM may be taking a cue from PSIA W. We have had the ski module as a must pass all at once for as long as I can remember.. We finally changed so that once you do pass the ski module, you own it. It used to be you had to pass both teach and ski within a year. Unless there was a specific reason, like a medical or injury reason, then we would have to petition the board to get a variance.

    I kept working at it and finally the skills, touch and accuracy overcame the athleticism.
     
  12. Mike King

    Mike King AKA Habacomike Instructor

    Joined:
    Nov 13, 2015
    Posts:
    1,658
    Location:
    Louisville CO/Aspen Snowmass
    Purportedly the changes were made to bring RM into the fold of national. Perhaps more is coming here or elsewhere.
     

Share This Page


  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice