Upper/Lower Body Coordination -- Countering Actions

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Upper/Lower Body Coordination -- Countering Actions

Postby SkierSynergy » Fri Nov 26, 2004 8:49 pm

The following descriptions of PMTS upper/lower body coordination (ULBC) is my summary of the various times that I have heard HH?s descriptions and also my interpretation of the instructions that were given to me as I worked on UBLC in my own skiing. In an earlier post I promised to compare PSIA and PMTS models of ULBC.

However, at the suggestion of a friend, I have decided to avoid doing so. Bringing in TTS models and concepts does not add to an understanding of PMTS and it would just potentially confuse people on the right track. So, for the most part, I?ll just stick to PMTS. For anyone interested in comparing, I would recommend looking at the relevant sections of the current PSIA Alpine Technical Manual, especially pp. 20-22, or the appropriate posts on EPIC. I?ll leave you to do that on your own.

In PMTS, The countering actions happen in relation to the tipping angle of the skis. For the most part this means that the biggest changes in countering actions happen during the transition between turns when the skis shift from one set of edges to the other ? though the countering actions can and should continue throughout if the edge angles increase.

Descriptions of the Countering Actions:
There are two countering actions in PMTS. The first is counter balance. In order to maintain a balanced position, as the lower body movements create tipping angles, the upper body must move independently in the opposite direction of the tipping.

If done in isolation, this creates a banana shape in the upper body to avoid simply leaning into the turn. If the tipping angles are high, the skier will have to ?crunch? or ?pinch? the obliques and other muscles on the side of the upper body to the outside of the turn. The skier may also feel a definite stretch of the muscles on the inside of the upper body. Counter balance movements work to maintain balance and direct force and pressure more directly through the edges and into the snow, resulting in more grip.

I have heard HH distinguish between weight and pressure on the inside foot. If one simply weights the inside foot without sufficient counter balance the skier will find himself dependent on the constancy of the inside leg to maintain balance. If the leg is kicked out, because of movement or conditions, the skier loses balance. If enough counter balance is present, and the pressure of inversion rather than weight shift creates the tipping, then changes in the movement/status of the inside foot/leg leave overall balance intact. This will become especially apparent in variable hard carving conditions: those times when it?s good carving, but with occasional patches of underlying hard ice and/or excessively soft patches. In these conditions, if you have insufficient counter balance, you will often find yourself either in slip-out flat spins on your side, or find yourself catching the inside tip and going over the front ? know these two situations well :o . Counter balancing allows the skier to get the grip that?s needed with better balance and control.

In addition to counter balance the skier can use counter movement. This is the hip and upper body rotation against the direction of the turn. When being instructed to do this, you will hear things such as: ?keep your belly button pointing to the outside of the turn,? ?look back in the opposite direction of the turn,? ?look back up hill? (at the start of the turn), ?keep looking downhill? at the end of the turn,? ?lead the turn with the inside hip,? etc, etc.

I think Harald has chosen to call this ?counter movement? rather than the more common ?counter rotation? so that it is not confused with more vague and varied notions in which counter movement and counter balance are not distinguished or the counter is created by leg steering. However, in PMTS these are distinct movements with a different priority of functions. Counter movement aids counter balance in supporting the lower body movements. Anyone who uses predominately counter balance movements will note that there will be a personal limit of sideways flexibility and strength available. Using only counter balance in hard carving turns will feel like doing oblique crunches every turn ? effective, but very tiring. Further, your lower body tipping ability will probably exceed your counter balance flexibility. Turning to the outside of the turn allows a hinging of the joints that is more forward and natural, and utilizes more muscles on the front of the abdomen. It uses a flexing that is more like sitting down in a chair.

Adding counter movement, the angles become deeper, the pressuring becomes greater, and the strength of the position becomes stronger ? all with less effort. Would you rather try to hold 400+ pounds of pressure from the side using your obliques or from the back in more of a leaning squat position? Counter movement also allows the stance leg to un-rotate and straighten easier. This helps to control/eliminate the effects of leg steering and place more of the load on a strongly aligned skeletal system. I have heard Harald refer to some studies that measured WC skiers having to hold 8-9 times of their body weight of loading in each turn. Counter movement is part of what makes this possible without losing balance and control, and without the threat of excessive stress on muscles and joints.

Countering Process Within a Turn
Now that we have a description of the movements and their functions, how and when do they happen? In PMTS, the countering actions happen in relation to the tipping actions of the skis rather than in relation to the position of the body to the fall line or the body within the turn. If the skis are tipped more the counter actions need to become greater in magnitude. Therefore the greatest changes happen at the release/transition.

The process looks something like the following: at the finish of a turn with high edge angles, the counter actions are also strong. The instant after the edges begin to release, the counter actions begin to release. They release in proportion to the amount that the skis flatten to the slope. When the skis are flat to the slope, the body is square. The instant after the skis begin to engage into the new turn, the countering actions for the new turn begin. Throughout the turn, the countering actions increase as the edge angles increase . . . and the process repeates.

Some additional notes:

I emphasized that the countering actions follow the movements of the feet. The upper body movements are done in order to support/facilitate the movements of the feet and increasing tipping angles. Counter actions happen to facilitate edge angles, not create them. They are not there to juice steering at the end of a turn or to redirect the skis in the unpressured state of the release, or to produce an anticipation/unwinding/steering into the next turn. They are there to block these tendencies.

If one releases, or ?unwinds? the counter ahead of the edge release, end of turn rotation happens. If the new countering actions happen before the new edges are engaged, beginning-of-turn rotation happens (since the skis are flat at this point an obvious skid occurs). During the turn, if the countering actions of the upper body are ahead of the actions of the feet, the skier loses connection with the skis: maximum pressuring is lost and the skier will be left with limited ability to make effective balance adjustments if the terrain or conditions dictate.

BigE pointed out a potential contradiction in what I said in a post and what Harald said in an earlier post.

BigE wrote:The following two quotes are contradictory:

SkierSynergy from Unweighting wrote:6. In PMTS there is no ?anticipation? or ?unwinding of the legs into the new turn? in any way similar to what happens in TTS models of ULBC. ? see my upcoming topic for further info on this.


From inside ski pull back thread:

harald wrote:If, as you say, your skis pivot when you release and flatten on steeps, just after you release that?s OK, as long as you are letting gravity and the unwinding of the body from the previous turn take your skis to the falline.


Anyone care to clarify? I was under the impression that unwinding is acceptable -- and clearly aided by unweighting.....


My comments were meant to contrast the role of unweighting and anticipation within TTSs and the actions of ULBC that used in PMTS.

Without going into a long comparison of TTS and PMTS models of ULBC (which I decided to avoid), I will say that Harald?s comments about ?unwinding? emphasized that the unwinding of the counter actions in a turn should be the result of the tipping actions of the feet and the natural forces of the turn. As long as they are not an active unwinding into steering ? which is prevalent in TTS notions of anticipation, keeping the upper body quietly faced toward the fall line, letting the skis steer under the body into a counter, etc., there is no problem. I think this is consistent with what I described above.

My later posts will also include some movement instructions and/or exercises that work effective ULBC/countering actions. Maybe others will follow suite.
Last edited by SkierSynergy on Mon Nov 29, 2004 8:15 pm, edited 1 time in total.
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Postby Uli » Mon Nov 29, 2004 2:04 pm

Jay - that's a great summary. It's so good, it leaves me speechless... :wink:
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Hinge analogy and restoring force

Postby SkierSynergy » Mon Nov 29, 2004 2:53 pm

Thanks Uli.

Good to see you on the forum.

another way that I have heard Harald talk about this is thinking of the ski as "hinged" at the edge on the snow.

Instead of the common notion of tipping the ski being created by pressing one edge of the ski into the snow, this analogy makes you think about tipping the ski as being created by picking the other edge off of the snow. Because the hinge point is offset from the longitudinal center line of your foot, the ski will want to flatten - it has restoring force that must be resisted. This issue becomes more important as the forces of the turn build.

This is what makes a Harb Carver more like a ski than an inline skate.
Inline skates don't have restorative force like a ski. In fact, they are the opposite: it takes positive action to keep them from tipping.

There are several things that can make the tipping easier. First counter balance to put the force on the ski closer to the hinge side and make the forces more perpendicular to the snow. Anything that places the load further away from the hing point or more parralel to the snow will tend to make the ski lose bite and make it harder to keep the tipping angle.

The concept is very common sense. If your are opening a floor style trap door. do you wnat the door to be heavy close to the hinge or close to the side you are trying to raise? No brainer, right?

Common things that will put the pressure away from the hinge point are whole body leaning, knee driving, leg steering, etc. If you examine each of these, the forces during a turn are placed more to the outside of the ski and/or more parallel to the surface of the snow.

The more you can place forces near the hinge point and perpendicular to the snow, the less you have to tip the skis for the same amount of bite.

So, if you want to have an easier time doing lower body movements, learn to use your upper body more effectively.

Just another note. Lots of people think of this being most applicable to ice, but it is more generally useful than that. For example, one issue that many soft snow skiers face is that the more they edge and pressure their skis, the more their skis slip out from under them -- often this is due to inefficient movements. So, an obvious thing that you can often see is good skiers not able to finish good arcs in soft snow. They just open it up and go longer and faster with their turns. I was just up at Mt. Hood with about 4 - 6 inches of new NW snow. The place was filled with racers and I was skiing with 4 guys who also Master's race. They could rip it fast, but they had a lot of trouble trying to finish a good arc. I think both Ice and soft thicker snow are less forgiving in this sense than premium carving snow.

However the same principles of pressure management and upper/lower body coordination that apply in ice also apply in soft snow. In fact, I find that the advantage of getting more effect with less edge is the key in soft snow. Just because it's soft doewsn't mean you can be soft on your upper/lower body coordination. As a side benefit it allows better balance and control in thicker and more varied snow conditions.

Anyone want to contribute some exercises for this thread?
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Postby Guest » Mon Nov 29, 2004 8:59 pm

Hi SkierSynergy:

You state:

"Common things that will put the pressure away from the hinge point are whole body leaning, knee driving, leg steering, etc. If you examine each of these, the forces are placed more to the outside of the ski and/or more parallel to the surface of the snow."


I don't fully understand what you're saying here. Wouldn't the load on the ski occur where the line extending from the center of mass in the direction of the combined Centrifigal Force + Gravity vector intersects the (bottom) surface of the ski? For determining where this point of loading occurs, I wouldn't think that it matters what shape the skier's body takes, merely the location of the center of mass and the direction of the force vector. (I'm certainly not an expert on this). Of course, with counterbalance (hip angulation?) or even knee drive, the angle of the ski to the snow surface increases beyond the critical angle. This would provide for some added safety margin before the ski loses grip due to: a) differential compression of the snow between the snow surface and the bottom of the ski's groove, b) longitudinal twisting of the ski, and c ) the bending of a weak ankle or knee outward. (The last sentence is wholey conjecture.)

I hope my thoughts aren't just gibberish, (and that they actually relate to what you're saying). I've been wondering about the purpose for creating edge angles in excess of the critical angle for some time. If you can explain this without too much effort, I'd be appreciative. But if it would take too long to set me straight, don't worry about responding. I just tune in and lurk here occasionally.

Thanks,

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Postby BigE » Tue Nov 30, 2004 8:28 am

jimmyD wrote:been wondering about the purpose for creating edge angles in excess of the critical angle for some time


To turn sharper.

As I understand it, the turn radius varies with the cosine of the edge angle. As ski turn radii are calculated with the ski flat to the snow, Cosine(edge angle) = 1. The stated turn radius is a measure of the sidecut only.

As you tip the ski onto edge, the angle changes, eg. at 45 degrees, if the stated sidecut radius = x then the actual turn radius = x*cos(45) = x/sqrt(2). where sqrt is the square root function.
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Re: Hinge analogy and restoring force

Postby BigE » Tue Nov 30, 2004 9:05 am

SkierSynergy wrote:Thanks Uli.

Good to see you on the forum.

another way that I have heard Harald talk about this is thinking of the ski as "hinged" at the edge on the snow.

Instead of the common notion of tipping the ski being created by pressing one edge of the ski into the snow, this analogy makes you think about tipping the ski as being created by picking the other edge off of the snow.

Because the hinge point is offset from the longitudinal center line of your foot, the ski will want to flatten - it has restoring force that must be resisted. This issue becomes more important as the forces of the turn build.

This is what makes a Harb Carver more like a ski than an inline skate.
Inline skates don't have restorative force like a ski. In fact, they are the opposite: it takes positive action to keep them from tipping.

In a parking lot yes, on a steeper slope, they want to tip to follow the attitude of the body.


I'm good up to here, so long as I am thinking that the LTE is the hinge point.

SkiSynergy wrote:There are several things that can make the tipping easier. First counter balance to put the force on the ski closer to the hinge side and make the forces more perpendicular to the snow. Anything that places the load further away from the hing point or more parralel to the snow will tend to make the ski lose bite and make it harder to keep the tipping angle.

The concept is very common sense. If your are opening a floor style trap door. do you wnat the door to be heavy close to the hinge or close to the side you are trying to raise? No brainer, right?


It depends. Do I want to lift it easily or do I want the door to stay shut?

I'm sorry, I don't follow this logic. It's easier to tip the skis if my CM is well off the hinge. If the trap door is heavy on the handle side! The door just wants to shut quickly from any angle, so that means it want's to "tip" over really quickly, and does not balance straight up and down very well.

skisynergy wrote:Common things that will put the pressure away from the hinge point are whole body leaning, knee driving, leg steering, etc. If you examine each of these, the forces during a turn are placed more to the outside of the ski and/or more parallel to the surface of the snow.


When the whole body leans, where does the pressure go? Why does it not stay on the edge? OR are you suggesting that whole body leaning pushes the ski out too much? I think the latter.

What is knee driving?

Yes, leg steering continuously moves the hinge point.

skisynergy wrote:The more you can place forces near the hinge point and perpendicular to the snow, the less you have to tip the skis for the same amount of bite.


Sorry, I don't understand. It sounds like you are trying to balance the inertia of the body moving overtop of the skiis with the pull of gravity above the skiis into the hill. If the skier is the trap door, gravity holds it open, and inertia is trying to close it. ( Or the other way around, it does not matter.)

skisynergy wrote:So, if you want to have an easier time doing lower body movements, learn to use your upper body more effectively.


Ok.


skisynergy wrote:Just another note. Lots of people think of this being most applicable to ice, but it is more generally useful than that. For example, one issue that many soft snow skiers face is that the more they edge and pressure their skis, the more their skis slip out from under them -- often this is due to inefficient movements. So, an obvious thing that you can often see is good skiers not able to finish good arcs in soft snow. They just open it up and go longer and faster with their turns. I was just up at Mt. Hood with about 4 - 6 inches of new NW snow. The place was filled with racers and I was skiing with 4 guys who also Master's race. They could rip it fast, but they had a lot of trouble trying to finish a good arc. I think both Ice and soft thicker snow are less forgiving in this sense than premium carving snow.

However the same principles of pressure management and upper/lower body coordination that apply in ice also apply in soft snow. In fact, I find that the advantage of getting more effect with less edge is the key in soft snow. Just because it's soft doewsn't mean you can be soft on your upper/lower body coordination. As a side benefit it allows better balance and control in thicker and more varied snow conditions.

Anyone want to contribute some exercises for this thread?


Is this what you are on about?

To hold an edge, don't push it out. The inertial forces that want to launch you to the outside of the turn must be balanced. They are balanced with the force of gravity pulling the upper body to the ground. The hinge point is the inside edge.

Upper body too close to the ground and you're skiis shear the top layer of the snow, to high and you either topple over or sideslip. The trick is to balance over the ski, so that the edge maintains it's track. Let the edge do the work; let it do the cutting. Do NOT add any additional forces yourself, beyond controlling the edge angle of the skis. You'll know you are really hooked up if the skiis are quiet.
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Response to Hinge analogy and edge hold.

Postby SkierSynergy » Tue Nov 30, 2004 12:53 pm

Guest (JimmyD) and BigE,

Thanks for the comments and questions about my last discussion of Harald?s Hinge analogy. The analogy struck a cord in me to work out some thinking about PMTS ULBC.

I will try to respond to/think out loud about all of the points in the last two posts, but I?ll have to do it over several responses of my own.

I could be outright wrong on some of my thinking or right on the effect, but wrong on the technical explanation. Let me follow up and think a little more out loud. The ULBC in PMTS directly supports and is adjusted to the tipping of the skis. I also think that the two counter actions (counter balance and counter movement) are distinct and have distinct functions.

I am thinking of counter balance as being the movement of the upper body (and CM) against the direction of the tipping.

I am thinking of the counter movement as being the hip and upper body rotation against the direction of the turn.

I think you can do both in isolation. You could just counter balance or just counter move or tend to mostly one and only a little of the other. Right now, I tend to have mostly counter balance and I?m working on more counter movement.

I am also guessing that they are hierarchical in their priority and effect on supporting lower body movements and they are sequential. That is you should start with counter balance first as a distinct movement at the start of the turn and add in counter movement after. Just thinking.

In practice, I think counter balance is more often used in isolation (usually at the top of the turn) and that counter movement is most often done along with counter balance. I see them mixed often at the bottom of the turn: laying the hip into the bottom of the turn and sitting down to increase the edge angle like a snowboarder doing a back side edge. However, I think that this only gives you good effects (in edge hold) if you also counter balance the upper body strongly at the same time. If you don?t you tend to sheer out ? and then there is also the issue of being out of balance. Unlike in TTS systems where countering is seen as a tensioned aid producing an active rotational unwinding into the next turn?s steering, In PMTS the ULBC movements are to support tipping and edge hold produced by the lower body. So, some of what I?m thinking through is distinct the effects of these movements on tipping and edge hold.

I hope that gives you an idea of where I?m coming from. What are the distinct and combined functions of these movements for tipping, angles, and edge grip; and what is the description/explanation for these effects within PMTS.

Oh, one other thing. I used the analogy to a trap door. This was bad word choice. I meant one of those doors in the floor that open upward on one side. This is like a ski raising one edge off the snow. So that the lighter it is near the edge coming up the easier it is to open.

Let me go out on a limb and say that from my own experience of these movements, I believe that counter balance adds more grip to a given edge angle and that counter movement allows deeper range of motion in ULBC related to tipping while also making counter balancing movements easier. So the net effect is deeper angles with better grip for that angle. This is the large scale everyday description that I would give from my experience of them.

So that was the general idea that I?m working off of. Now let me consider some of the responses:

Wouldn't the load on the ski occur where the line extending from the center of mass in the direction of the combined Centrifigal Force + Gravity vector intersects the (bottom) surface of the ski?


This sounds right to me. However,

For determining where this point of loading occurs, I wouldn't think that it matters what shape the skier's body takes, merely the location of the center of mass and the direction of the force vector.


Some of the simple mathematical discussions of the carving issue seem to see the body as a fixed lump of CM that, given a certain angle to the skis, has a critical limit of hold. If this is true then for a given edge angle and related CM distance inside the skis, there wil be an optimum body set-up that you would want to achieve and quietly keep. To do less would be to lose edge caused turning force and to do more would be to exceed the holding capability of the ski.

This is what I am questioning. I am guessing that the countering actions affect both the location of the center of mass, the intersection point of the force on the ski, and the direction (or angle) of the force vector; and that is why they are so effective at adding edge angle and add more grip for a given edge angle. I am also guessing that it is mainly the counter balancing movement that is most effective for grip given a certain edge angle.

I am guessing that the counter balancing movements place the intersection of the ski and the force vector closer to the hinge point of the skis and make it less of a sheering force. The few situations that I picked out as negative change either the location of where the force vector intersects the ski to further away from the hinge (edge) or the angle of the vector ? or both ? and this is one possible reason why grip is less.

Ok enough for now.

PS Bige, I think your first quote of my post is mixed in with other stuff that was not in my post. I?ll try to write more later. I hope this let?s you see where I was coming from.
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Oops!

Postby BigE » Tue Nov 30, 2004 2:09 pm

I fixed the quote. Yes, some inline thinking of mine got mixed into your quote.

I can understand the hinging of the skiis on the snow, if that's the idea, just not the relation to CM. If I consider the skier as an upside down pendulum, then the tipping of the edge and position of the upper body are completely determined up to a point simply by inclination.

Is what you call counter balancing plus counter movement (counter rotation) actually just angulation?

IMHO, angulation is necessary when coming to the deepest part of the turn. If you don't absorb energy via flexion, you run into the very real danger of just pushing the looser snow off the hill, losing edge hold and with it the platform on which you are balanced.

eg. Hit a small bump in a purely inclined position and your edges will break free, but angulation ( or counter balance/counter movement) keeps the legs free to absorb the shock, the skis keep cutting, and the skier remains balanced.

Are we on the same page?
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Postby piggyslayer » Tue Nov 30, 2004 7:27 pm

Wow, this thread is going fast, I am still on the first Skier Synergy post and am reading and trying to understand the hinge thing.

I have a small comments related to first post:
This helps to control/eliminate the effects of leg steering and place more of the load on a strongly aligned skeletal system.

This is fantastic quote. This is why Javelin is so effective for many of us, especially once with BTE tendencies, this is why countering actions are so effective in learning one legged Harb Carving as well.
I am not disputing the point that counter help in fighting rotational tendencies as well as helps with keeping the skeletally strong position with knee NOT rotated/extended inwards.
What I think, however, is that any explicit skier initiated rotation and pointing will remove benefit of counter. At least, my experiments tell me that if I try to follow rusty or dnar advice and ?point? the free foot the stance foot LOOSES its strong skeletal position no matter how counter rotated I am.

The process looks something like the following: at the finish of a turn with high edge angles, the counter actions are also strong. The instant after the edges begin to release, the counter actions begin to release. They release in proportion to the amount that the skis flatten to the slope. When the skis are flat to the slope, the body is square. The instant after the skis begin to engage into the new turn, the countering actions for the new turn begin. Throughout the turn, the countering actions increase as the edge angles increase . . . and the process repeates.

Coutering actions follow movements of the feet.

I like to think about this from a slightly different point of view. In this way the ?when? of counter movement, I think, happens very automatically.

At the end of the turn the coming out of the counter is simply controlled by relaxing and LTE tipping. If I relax stance leg and hip and LTE tip it the counter is gone. This is, I think, in part due to the fact that counter movement produces a skeletally strong position of the stance leg, if the leg is relaxed and is tipped the upper body natural reaction is to adjust itself and the position becomes more square automatically (the effect is both ways upper body acts on improving stance leg alignment and stance/hip relaxation affects (removes) the counter).

At the beginning of the turn new counter movement is stated by pole plant, pole is used a bit as a lever on which the counter ?rotation? is initialized.

Within the turn, experimenting with strong arm exercise will, I think, develop good counter movements. In fact I have added strong arm drill to my one legged Harb Carving and I am benefiting from this combination.
Strong arm forces the resitance on the inside part of the upper body and thus should be in synergy (no pun intended) to hip counter rotation.

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Postby milesb » Tue Nov 30, 2004 7:38 pm

A quick question about the fulcrum thing..
For clarity's sake, let's make the skis very wide, like 100mm. If you make the edge of that ski the "pivot point", wouldn't the tipping action have to originate from the knee, which would add an active rotary force?

Or is the fulcrum more of an imagery thing?
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Hinge point - real or analogy

Postby SkierSynergy » Wed Dec 01, 2004 11:28 am

milesb wrote:A quick question about the fulcrum thing..
For clarity's sake, let's make the skis very wide, like 100mm. If you make the edge of that ski the "pivot point", wouldn't the tipping action have to originate from the knee, which would add an active rotary force?

Or is the fulcrum more of an imagery thing?



I think the idea of a ski having a hinging or pivoting line is real, but it is affected by the softness of the snow. In very, very hard snow a wider waisted ski takes more force to get up on edge and it will want to flatten more.

In soft snow the edge of the ski is actually pushed into the snow, the hinge or pivot line is moved more under the foot and there is a more even pressure gradient across the base of the ski. The softer the snow, the easier it is to get the skis tipped.

There was this long and not so fruitful set of exchanges on Epic about whether we ski on our edges or on the bases of the skis. Well it's obvious that both is true; which is more true?. . . it depends.

The idea of a hinge line and the concept of restoring force make clear why certain equipment suggestions are generally given to associated alignment situations.

For example, a knock kneed skier tends to get too much edge angle on their stance ski too easily and too fast. A wider ski slows this down and takes more effort to maintain the edge. The same knock kneed skier has trouble releasing -- letting go of the edge and letting their skis flatten to the slope during transition. A wider ski wants to do this more than immediately rolling onto the next edge. Everything else being equal, wider skis will tend to facilitate more of a float in the transition.


So, to directly answer your question. A wider ski on hard snow will take stronger movements to get it onto edge. If you are using effective and efficient PMTS movements those movements will have to be stronger and more definite. If you are using knee based movements to get the ski on edge, then those will have to be more pronounced.

My guess would be that for a TTS based skier, hard snow, short turns and a very wide ski would make the origin and the negative effects of the movements most pronounced. You would tend to see even more up and down, more steering, more skidding, and more radical and athletic body movements.
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Postby milesb » Wed Dec 01, 2004 11:57 am

OK, I guess I wasn't clear on what I was asking. Let's use your trap door example. Glue your left foot to the center of the door. Let's say the hinge is to the left of your left foot. Now try to open the door by tipping your left ankle. Doesn't work, does it! The only way I can see to open the door is to move the left knee up and out, which puts alot of rotary force on the foot. Correct?
Anyways, the reason I'm asking, I skied some very hard snow on fat skis a few days ago. While the hinge thing worked great for me as an image, when I made it an actual thing during weighted releases, it caused the problem I described above. Actually, weighted releases on hard snow with fat skis are very hard to do right with any kind of cue!
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Postby piggyslayer » Wed Dec 01, 2004 2:36 pm

Jay, milesb

Question (probably weird) inspired by your discussion:
For example, a knock kneed skier tends to get too much edge angle on their stance ski too easily and too fast. A wider ski slows this down and takes more effort to maintain the edge. The same knock kneed skier has trouble releasing -- letting go of the edge and letting their skis flatten to the slope during transition. A wider ski wants to do this more than immediately rolling onto the next edge. Everything else being equal, wider skis will tend to facilitate more of a float in the transition.


Would it not make sense for a knock kneed skier on wide skis and to have its bindings/boots placed closer to the outside edge of each ski?

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Binding position for knock kneed alignment

Postby SkierSynergy » Wed Dec 01, 2004 2:56 pm

piggyslayer wrote:Jay, milesb

Question (probably weird) inspired by your discussion:
For example, a knock kneed skier tends to get too much edge angle on their stance ski too easily and too fast. A wider ski slows this down and takes more effort to maintain the edge. The same knock kneed skier has trouble releasing -- letting go of the edge and letting their skis flatten to the slope during transition. A wider ski wants to do this more than immediately rolling onto the next edge. Everything else being equal, wider skis will tend to facilitate more of a float in the transition.


Would it not make sense for a knock kneed skier on wide skis and to have its bindings/boots placed closer to the outside edge of each ski?

Robert


Interesting idea. In principle it makes sense, though, of course, the easiest thing is just to get a good footbed and boot adjustments. Hmmmm, maybe in really extreme cases of deformity, etc.

Has anyone out there tried this?
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Off subject but in reply to the last post

Postby tanman » Wed Dec 01, 2004 4:53 pm

I am knock kneed by 2.5 degrees. However, my general purpose piste ski is a Elan HCX Hyper Flex which has a 62mm waist shimmed to the ideal angles. I find that proper movement patterns ie PMTS can over the perceived mismatch to equipment to alignment. I like a narrow ski because I find it easier to skis on all four edges and I can get on the outer edge much easier ie weighted releases, one legged short turns. All I have to be aware of is to always keep the new stance leg passive are the release. I have a pair of Atomic Metron B5 and an Elan Mantis 777 and I find it takes more effort to ski it in the outside edge than the HCX. So although I believe the a wider ski does probably do well for my alignment, I have to also have to make a compromise and not be as effective on the outside edge especially in the bumps. Please tell me if I am wrong.
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