Page 3 of 10 FirstFirst 1 2 3 4 5 8 ... LastLast
Results 21 to 30 of 91

Thread: Inside Hip Drive discussion

  1. #21
    Looking for an apartment Snow Sport Instructor
    Join Date
    Dec 2011
    Posts
    344
    Quote Originally Posted by Coach Rick View Post
    The new inside foot will advance, it has to. You simply try to limit it to the least amount necessary. Create the new counter by driving the new inside hip, and the foot gets dragged forward by that action, only the most minimum amount it has to. Inside foot lead will be the result, not the goal, and it will be held to only necessary levels, dictated by how much range of dorsiflexion capacity you have in your ankle, and how much the stiffness of your boots will allow you to to exploit that range.
    Counter is used to advance the cm ahead of the base of support in order to resist angular acceleration. There is negative or very little force in the top half of the turn so why would you want to counter much of any in the top part of the turn?

    I see keeping the inside hip up and and ahead as a separate movement pattern from driving the inside hip.
    Last edited by Pierre; October 7th, 2012 at 06:40 PM.

  2. #22
    I have my own seat in the pub Skier Village Coach Coach Rick's Avatar
    Join Date
    May 2011
    Location
    City Above The Clouds, Colorado
    Posts
    3,834
    Quote Originally Posted by Pierre View Post
    Counter is used to advance the cm ahead of the base of support in order to resist angular acceleration.
    Pierre, care to expand on that a bit? As in, how counter moves the CM forward, and what you mean by "resisting angular acceleration". I'm sure everyone would like to hear your thoughts on it.
    YOUR SKI COACH - Bringing world class skills to the recreational skier

    * Instructional DVDs * Technical Articles * On Hill Coaching

    www.YourSkiCoach.com

  3. #23
    Looking for an apartment Snow Sport Instructor
    Join Date
    Dec 2011
    Posts
    344
    Quote Originally Posted by Coach Rick View Post
    Pierre, care to expand on that a bit? As in, how counter moves the CM forward, and what you mean by "resisting angular acceleration". I'm sure everyone would like to hear your thoughts on it.
    angular acceleration is a fancy way of throwing out the the fact that you are turning as you move through the gravity line. Centrifugal force plus gravity. When acceleration takes place we tend to fall into the back seat. You need to keep the cm stacked over the outside leg. Counter moves the cm ahead because it rotates the entire upper body in relation to the outside leg. We could move the cm by flexing the ankles but that would not properly stack the cm over the outside leg.

    Where skiers run into problems is when they artificially develop counter so they can move the hips to edge the skis. The problem is the cm is to far forward of the outside leg. The natural reaction is to open the outside ankle to move the cm back over the outside leg as force builds. Classic back seat. That move shuts down guidance of the skis in the arc. In order to close the outside ankle again the normal reaction is to drive through with the outside hand. That leads to dropping the inside hip and hanging onto the turn too long in the finish of the turn.

    My explanation still does not say how you raise the inside hip and keep it up throughout the turn. My explanation still does not say what drives the inside hip forward. I want to see what other people think before I give my take on it.

    The problem with these discussions is that everybody knows you are suppose to keep the inside hip up and ahead of the outside hip but nobody really offers up explanations as to HOW that is best accomplished. Keeping the inside hip up and forward is one of the few movement patterns that few people pick up on their own and usually must be taught. I know from personal experience and teaching this so called "Inside Hip Drive" (a term easily misunderstood) that just telling someone they are dropping the inside hip and squaring to the skis does nothing to help the skier progress. Many many ski instructors are stuck on this for lack of understanding so this discussion is very important.

  4. #24
    Furnished the apartment Skier Village Coach
    Join Date
    Oct 2011
    Posts
    564
    Pierre, I cannot really puzzle your statements together.

    You say that counter moves the CM ahead. Its true that this happens to some extend, however, the COM of the upper body is more or less in front of the hip, so a rotation around the hip joint should move the CM to the outside more than forward. A little forward yes, but hardly to cause any problems in the fore-aft place.
    Also, even if this would be the case, how can this be a problem if the natural turn forces, what you call angular acceleration, work very hard to put you in the back seat?

    Since you view hip up and forward as different from inside hip drive, what is your definition of inside hip drive?



    Quote Originally Posted by Pierre View Post
    There is negative or very little force in the top half of the turn so why would you want to counter much of any in the top part of the turn?
    In racing the answer is clear, you want to create as much force as possible as early as possible in the turn, because it is faster.

    Even outside of racing you want the skis to have started to turn a lot by the fall line, otherwise you may spend to much time in the fall line and loose speed control.

  5. #25
    Looking for an apartment Snow Sport Instructor
    Join Date
    Dec 2011
    Posts
    344
    Quote Originally Posted by Jamt View Post
    Pierre, I cannot really puzzle your statements together.

    You say that counter moves the CM ahead. Its true that this happens to some extend, however, the COM of the upper body is more or less in front of the hip, so a rotation around the hip joint should move the CM to the outside more than forward. A little forward yes, but hardly to cause any problems in the fore-aft place.
    Also, even if this would be the case, how can this be a problem if the natural turn forces, what you call angular acceleration, work very hard to put you in the back seat?
    I thought about what I had typed a bit later and wondered if there would be any confusion. A better explanation is that the cm needs to move as you described in order to stay in alignment skeletally through the outside leg. If my memory serves me correctly I think the movement to the outside as you describe is due to the fact that the force is not aligned through the center of the leg but off to the inside because the ski edges are not in alignment with the center of your foot. The hip joint/pelvis is the only thing that will align the cm through the line of force to the inside edge of the outside ski.

    Since you view hip up and forward as different from inside hip drive, what is your definition of inside hip drive?
    Hip drive implies driven. In my opinion you cannot use the inside half to drive the inside half efficiently. You drive the inside half with the outside half through ankle flexion, leg extension and outside leg rotation. In order to drive the inside half, the inside half must be under functional tension. The best way to tension the inside half is through isometrically firing the inside hip rotators enough to keep the inside hip level. The hip rotators are powerful and able to handle leveling the hips plus any torque you apply to the outside leg to facilitate a very smooth progressive edge very early in the turn. (Rotary to an edge engages the ski tips and directs them into the new turn. This is not pivoting).

    The more torque you use to engage the tips and rocket to a high edge the more the inside hip rotators insometrically contract to hold the cm in alignment through the line of force. The result of powering up the outside leg along with isometric contraction of the inside hip rotators (strong inside half)very much feels like the inside half is being driven forward.




    In racing the answer is clear, you want to create as much force as possible as early as possible in the turn, because it is faster.

    Even outside of racing you want the skis to have started to turn a lot by the fall line, otherwise you may spend to much time in the fall line and loose speed control.
    When the clock matters you want to drive the cm downhill towards the next gate (using fastest line) A skating type of action begining in the previous turn as an ILE is a very good way the accelerate the cm downhill.

    Outside of the "Hey guys watch this" mode the recreational skier is usually concerned more with not intentionally using force to push the cm. You can develop higher edge angles higher in the turn by not using an extension that moves the cm down hill. Given the same size turn, if you don't push the cm downhill the natural line the cm will take will intercept the arc (want to cross the arc) of your skis higher in the turn. Anytime your cm wants to cross the arc you can create centrifugal force against the skis. Since this takes place higher in the turn than with a skate type movement you can reach a higher edge angle at the apex with less force buildup. You can also let go of your turn and move into your next turn much earlier. That sets you up to reach with the feet and keep edging higher with each sucessive turn.

  6. #26
    Furnished the apartment Skier Village Coach
    Join Date
    Oct 2011
    Posts
    564
    Thanks Pierre, I think we are more on the same page than it may appear

    Just to be clear, when I talk about creating forces I am not advocating any pushing movement. That's a big no-no, unless you are skating. After the first one or two gates its more about managing the forces then muscularly producing them. In a high energy turn the forces may be 3-4 Gs, you cannot skate against that.

    I think it is important to make the distinction of what early engagement really is. What we talk about is the relative position in the turn, or where the skis are pointing. This is not the same thing as early on the time axis. Quite the opposite actually.

    In reality early counter and hip angulation delays the engagement a bit in time, because since you are "folding" the body the feet are pulled up a bit, but ones the engagement comes the force will be enormous. It sounds a bit counterintutive that you are delaying the engagement when you are trying to create early engagement, but the "early" is more about what direction the skis are pointing, i.e. where in the turn it begins, than when in time the big forces start to kick in. Before the skis are engaged you are traveling in more or less a straight line as seen from above. In effect this means that you are going straight a bit longer and turning sharper in the actual turn, thus producing a more direct line and this is what its all about in racing. On the other side of the spectrum, the fastest way to get a bit of engagement is to extend muscularly early in the turn both from an angular and time perspective, but that will destroy any chance of having high edge angles and big forces a bit later in the turn. "Don't rush the turns"



    About the torque. How do you produce that? IMO you can only produce a torque for a brief moment of time, by rotating the femurs, because that torque will try to twist the body away. This is the same as trying to create the counter late when the skis are already engaged. I don't like the idea of having that torque passing through my knees. IMO the proper way to engage the tips for an extended time is to be fore and edge. A bit torque just as the tips engage is good, but not more than that.

  7. #27
    Moderator Snow Sport InstructorSkier Village Coach LiquidFeet's Avatar
    Join Date
    Dec 2011
    Posts
    2,419
    Pierre, you say:
    Outside of the "Hey guys watch this" mode the recreational skier is usually concerned more with not intentionally using force to push the cm. You can develop higher edge angles higher in the turn by not using an extension that moves the cm down hill. Given the same size turn, if you don't push the cm downhill the natural line the cm will take will intercept the arc (want to cross the arc) of your skis higher in the turn. Anytime your cm wants to cross the arc you can create centrifugal force against the skis. Since this takes place higher in the turn than with a skate type movement you can reach a higher edge angle at the apex with less force buildup. You can also let go of your turn and move into your next turn much earlier. That sets you up to reach with the feet and keep edging higher with each sucessive turn.

    You are talking here about initiating a new turn by releasing the old outside ski (by relaxing that leg) and allowing the body to pass across the skis and into the inside of the new turn. I want to add that you still need to move that side's hip up and forward as you relax that leg to avoid dumping the hip into the back seat.

    Everything in red above is all new information for me as a reader in skiing. A releasing move can produce higher edge angles at the apex with less force buildup - didn't know that!
    Last edited by LiquidFeet; October 9th, 2012 at 11:11 AM.

  8. #28
    Furnished the apartment Skier Village Coach
    Join Date
    Oct 2011
    Posts
    564
    Quote Originally Posted by LiquidFeet View Post
    Jamt, you say:
    No, that was Pierre. I think Pierre and I are saying approximately the same thing, but in different ways. We don't look at things 100% the same way, but similar enough to not fight about

  9. #29
    Moderator Snow Sport InstructorSkier Village Coach LiquidFeet's Avatar
    Join Date
    Dec 2011
    Posts
    2,419
    Whoops. So do you agree, Jamt, that releasing the new inside leg instead of extending the new outside leg can produce these things that Pierre points out?

  10. #30
    My horse knows his own way home Snow Sport Instructor SMJ's Avatar
    Join Date
    May 2011
    Location
    Central MA
    Posts
    2,471
    Blog Entries
    7
    As the OP I have to say this has gotten way too technical and probably should be in the Coaches discussion forum, not the Village Ride and Ski school.

    I think that most developing skiers and students would have given up long ago on this thread, when the purpose of it was to understand in simple terms what Inside Hip drive was.

    I think I can summarize now on the level of detail that is necessary for 99% of the people who care.

    At the end of a Left turn.
    Just before transition you start to drive your Right (outside) hip forward but not to the Right. This reduces the counter that was formed by the Left hip being driven forward.

    As the Right turn develops you keep that Right hip driving forward, it is now the inside hip and is now in a countered position, pointing Left of the skis.

    At the end of this Right turn.
    Just before transition to a Left turn you start to drive the Left hip forward (and not to the left) to reduce the counter that driving the Right hip was creating, this then becomes the inside hip as the Left turn develops.


    So it is still Inside Hip drive, but as it starts at or just before transition it starts as outside hip drive and becomes inside hip drive.

    Is this accurate?

    Please keep your answers simple.
    I need to be a conqueror, a liberator of my potential, kept prisoner all these years.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •