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PMTS Camp at Hood - Page 6

post #151 of 254
Quote:
Originally Posted by MilesB
Just a note, the PMTS movements do not really translate into those "skills". Because they serve different purposes than the "skills", mainly to support more tipping of the free foot and maintaining stance ski balance. However, some of the secondary effects of the movements can correlate with those skills.
That is all.
Actually, I think that this is a point that is worthy of discussion.

A "skill" is a "proficiency, facility, or dexterity that is acquired or developed through training or experience". In this case, there is a skill of managing pressure on the ski by moving the feet in such a way as to increase or decrease pressure fore/aft or laterally (between the two feet). Your movements of pulling your foot back and lifting your foot are two movements within the constellation of movements that make up this skill.

Therefore, these movements are non-exclusive examples of movements that constitute pressure management skills. They are not synonymous, and that's not what I intended to imply. However, there are parallels between the two paradigms as I understand them, and this is an example.

Of course, if the goal is to have one paradigm be the exclusive purveyor of truth, then this conversation has no opportunity to create learning. That is not my perception or belief, but it often seems to return there.
post #152 of 254
Quote:
Originally Posted by Max_501
Interesting...and that does make sense. So the only thing left that I can't grasp is how PSIMan manages to release.
Forces.

When the combination of gravity and centripetal force combine to overcome the force of gravity that keeps him on his edges (i.e., "inside" the turn), his "upper body mass" is pulled downhill to cross over his skis. That's why I know that there is pressure on that downhill ski (although there is also some on the uphill ski, of course).

Note: without the stops, he would, of course, tumble into the inside of the turn. However, because there are stops, his hips can move only so far to the inside. Because they are a few inches from the surface, the friction from the snow slowing his COM's downhill movement is eventually overcome by the momentum of his COM, causing it to crossover his skis.
post #153 of 254
Quote:
Originally Posted by doublediamond223
I'm as obsessive about technique as anyone, but holy shit. We're analyzing the movements of a metal object.... Must be summer!
The advantage to my way of thinking is that we eliminate a number of variables when we look at PSIman. There are a lot of things that skiers think that they must do that PSIman cannot do. As a result, we have proof that those things are not necessary to make nice, mostly carved turns.

I am a scientist. The scientific method involves removing as many variables as possible in order to determine cause and effect. In the case of PSIman, we've removed a lot: intent, flex, muscle forces, most angulation, etc. Yet, he can still make pretty nice turns. How? Why? What can we learn from this about what is necessary and what is compensatory? And, furthermore, what can we learn about how we can adjust once we've identified the minimally necessary components?
post #154 of 254
Quote:
Originally Posted by HeluvaSkier
Regarding PSIMAN's legs I think we already established that it is not a real-world scenario. A normal human could probably not carve a turn like that without bending the inside leg (going back to my original very long post). Also remember some of the possible restraints of the model's application.
I think it may be possible using purely hip movements (which is, after all, what PSIman is doing). It is possible that most of us cannot move our hips as much as PSIman can, but we may actually be able to. I was surprised when Deb Armstrong had us exercise our hip movements just how much movement is available there.
post #155 of 254
Wow, this thing really got long :
Lots of thoughts.
1. PSIA man: George Twardokkens said, at the 1988 USSCA Acadamy, that no one had been able to make a skiing machine. He showed slides of his attemps with a sled device. PSIA man can't cross without some type of pressure management. (the sled tipped over every time)
2. PMTS takes it's model from Slalom skiing and Harald uses SL cut skis to teach it. WC SL skiers pick up their inside foot and move it closer to the outside to be able to tighten their line on the gate.(first hand observation)
3. Harald's tracks diverge and converge in his "big angle" turns.(also first hand observation)
4. GS skiers use unweighting and pivot(stivot) moves to make tighter radius runs with straighter skis to "cut off" their lines. Hence the "up and down" moves. (more first hand obsevation)
5. Inside ski = tighter radius. Two RR track arcs are portions of concentric circles. The inside one has a smaller radius. (even in a small section of the posted photo) It appears that my post on page two has been overlooked. The "local steering angle" of the tip is part of the mix that makes it possible without having more weight or edge angle on the inside ski. (one more reason for pulling the inside foot back)
6. Any ski turn is a big pot of stew with lots of ingredients. The most important one is the remarkable talents of the human body to be able to make all the moves necessary at the same time. Anyone can draw a bow across a violin. It takes a lot to co-ordinate the sound the ear hears with the touch of the fingers, etc to make a note(let alone a beautiful piece of music) If you only taste one or two ingredients you don't get a very good idea of what it really tastes like.
post #156 of 254
Thread Starter 
Quote:
Originally Posted by ssh
Forces.

When the combination of gravity and centripetal force combine to overcome the force of gravity that keeps him on his edges (i.e., "inside" the turn), his "upper body mass" is pulled downhill to cross over his skis. That's why I know that there is pressure on that downhill ski (although there is also some on the uphill ski, of course).
I don't see this happening in a real world senario. Perhaps if you were traveling at warp speed using a very slight edge angle, but even then its more likely that you'd just skid your skis.
post #157 of 254
Thread Starter 
Quote:
Originally Posted by ssh
The advantage to my way of thinking is that we eliminate a number of variables when we look at PSIman. There are a lot of things that skiers think that they must do that PSIman cannot do. As a result, we have proof that those things are not necessary to make nice, mostly carved turns.

I am a scientist. The scientific method involves removing as many variables as possible in order to determine cause and effect. In the case of PSIman, we've removed a lot: intent, flex, muscle forces, most angulation, etc. Yet, he can still make pretty nice turns. How? Why? What can we learn from this about what is necessary and what is compensatory? And, furthermore, what can we learn about how we can adjust once we've identified the minimally necessary components?
And how do you know PSIMan is making these really nice turns? You'd have to take the 3D model and run it down a slope in a realtime 3D environment with a very good physics model.
post #158 of 254
Thread Starter 
Quote:
Originally Posted by ssh
I think it may be possible using purely hip movements (which is, after all, what PSIman is doing). It is possible that most of us cannot move our hips as much as PSIman can, but we may actually be able to. I was surprised when Deb Armstrong had us exercise our hip movements just how much movement is available there.
To get the vertical leg separation the pelvis would have to tilt laterally quite a bit. I tried it and I sure can't do it. If my inside leg is higher then my outside leg (like on a slope) and then I straighten my inside leg my outside leg lightens. therefore it carries less weight than the inside leg which is opposite of what you are saying PSIMan is doing. The more I think about it the less I believe that model works for real world skiing.
post #159 of 254
back to the radius differences..

In order to make the radius's the same as suggested, 2 offset circles. let's assume 4" of seperation between the boots, allow for 2" width of the waist of the ski, this would require 6" between the arc's.

In order to make the turning radius truly the same, there would have to be 6" of tip lead at the transition of each turn and the boots would need to occupy the same space at this transition (one leading the other by 6")

There is no physical way to fix this as far as I know other than to accept that the skis will take a different radius turn and our bodies do what is necessary to keep us from falling over.

How we make it happen is where we differ. Steer, guide, skid, load, etc. it has to happen. When you find the way that works for you great. Please though, don't tell me this is the ONLY way ito make it happen. This is part of what makes skiing and instructing so much fun for me. As long as we find our way there.

I just want to make sure we keep exploring the ideas and learn from them.
post #160 of 254
Thread Starter 
Quote:
Originally Posted by ssh
In this case, there is a skill of managing pressure on the ski by moving the feet in such a way as to increase or decrease pressure fore/aft or laterally (between the two feet). Your movements of pulling your foot back and lifting your foot are two movements within the constellation of movements that make up this skill.

Therefore, these movements are non-exclusive examples of movements that constitute pressure management skills.
In PMTS the primary benefit of pulling the free foot back is to keep the skier centered over his skis. Obviously this increases pressure on the skis but its a secondary benefit of being in balance over the skis.
post #161 of 254
Max,

Are you suggesting that you must pull the foot back to balance better?

And would "balancing better" imply better pressure control?

So, is the intent to improve pressure control or is there some other measure of "balance better" that I am missing?
post #162 of 254
Thread Starter 
Quote:
Originally Posted by BigE
Max,

Are you suggesting that you must pull the foot back to balance better?

And would "balancing better" imply better pressure control?

So, is the intent to improve pressure control or is there some other measure of "balance better" that I am missing?
Balance was probably the wrong word. Maybe centered is better. If I don't pull my free foot back it jets out at the end of the turn putting me in the back seat for the new turn. As long as I pull the free foot back I can stay centered over my skis and be in a strong position for my next turn.

Pressure control is not part of the intent of my movement although it is a benefit of it.
post #163 of 254
Quote:
Originally Posted by Max_501
And how do you know PSIMan is making these really nice turns? You'd have to take the 3D model and run it down a slope in a realtime 3D environment with a very good physics model.
'cause I've seen him live.
post #164 of 254
Quote:
Originally Posted by Max_501
I don't see this happening in a real world senario. Perhaps if you were traveling at warp speed using a very slight edge angle, but even then its more likely that you'd just skid your skis.
That's pretty much what I was doing in the video from this April that got ripped to shreds due to my "up move".
post #165 of 254
Quote:
Originally Posted by Max_501
To get the vertical leg separation the pelvis would have to tilt laterally quite a bit. I tried it and I sure can't do it. If my inside leg is higher then my outside leg (like on a slope) and then I straighten my inside leg my outside leg lightens. therefore it carries less weight than the inside leg which is opposite of what you are saying PSIMan is doing. The more I think about it the less I believe that model works for real world skiing.
If you stand on both feet and pivot your pelvis about your spine, how much lift differential can you get with your feet without a differential in knee flex? I get 4" or 5". If I take my body and incline it in a turn with that kind of differential, I can get some reasonable angles of my body relative to horizontal.
post #166 of 254
Quote:
Originally Posted by Max_501
In PMTS the primary benefit of pulling the free foot back is to keep the skier centered over his skis. Obviously this increases pressure on the skis but its a secondary benefit of being in balance over the skis.
The "reason" for it is immaterial. It is the totality of the effects that is important, since they all play simultaneously and in an entirely synergistic way.

So, you think that you are doing it to stay centered. That's great. But, it's not the only outcome. It may not even be the most important outcome. But, it may be the one that the designer of your education has chosen to communicate because he/she finds it more effective for their purposes.

Some of the best teachers I know have asked me to do something without telling me why. They allow me to discover for myself what I feel the outcome is. But, there may be many outcomes, only some of which I actually feel. That's why those teachers need a complete bag of tools for communicating with folks like me.
post #167 of 254
Quote:
Originally Posted by Max_501
Balance was probably the wrong word. Maybe centered is better. If I don't pull my free foot back it jets out at the end of the turn putting me in the back seat for the new turn. As long as I pull the free foot back I can stay centered over my skis and be in a strong position for my next turn.

Pressure control is not part of the intent of my movement although it is a benefit of it.
Why bother to stay centered? What is centered? Your weight/pressure? And why is that important?

Do you see the circle here?
post #168 of 254
Thread Starter 
Quote:
Originally Posted by ssh
If you stand on both feet and pivot your pelvis about your spine, how much lift differential can you get with your feet without a differential in knee flex? I get 4" or 5". If I take my body and incline it in a turn with that kind of differential, I can get some reasonable angles of my body relative to horizontal.
Lets see if I'm picturing this correctly. Are you saying that if you put your right foot up on a block that is 4" high you can keep that leg perfectly straight while your left leg (on the floor) is also perfectly straight? And if so then you can move your hips to the right of the right leg (so they are to the inside of a turn) and the left foot is still touching the ground in such a way that it could carry most of the weight in a turn?
post #169 of 254
Thread Starter 
Quote:
Originally Posted by ssh
Why bother to stay centered? What is centered? Your weight/pressure? And why is that important?

Do you see the circle here?
Not really. I already explained why I want to stay centered. Don't know why you are asking a question I already answered.
post #170 of 254
Thread Starter 
Quote:
Originally Posted by ssh
'cause I've seen him live.
What does that mean?
post #171 of 254
:

Hey Max any chance you might post this as trip report. It might be nice to see this in that context. I have a couple questions but would not dare post in this lofty thread.

I have now read almost every post here (A couple of times)

Some good stuff from the usual suspects.

A few of you should be ashamed of yourselves
post #172 of 254
Thread Starter 
Quote:
Originally Posted by ssh
The "reason" for it is immaterial.
On the one had 'intent' is so very important. However, in this case its immaterial?
post #173 of 254
Thread Starter 
Quote:
Originally Posted by MTT
: I have now read almost every post here (A couple of times)
...that's impressive. This thread really has gone far off topic.
post #174 of 254
Quote:
Originally Posted by Max_501
What does that mean?
I have see PSIman "ski". He exists. He "skis" on snow (and on a tilted table).
post #175 of 254
Quote:
Originally Posted by Max_501
On the one had 'intent' is so very important. However, in this case its immaterial?
Exactly!

I know, it seems that I'm being trite, but that's not the intent (ahem). If I intend to tighten my turn and so push my heels out, does the intent make any difference in terms of the outcome?

Or, on the other hand, if I like a little hand flash at the start of my turn, does that intent have any bearing on the outcome when it causes some really "interesting" effects between my skis and the snow?

No, it doesn't.

If I want to understand why someone is doing what they are doing, understanding their intent is important. If, on the other hand, I'm studying cause and effect, the reason someone does something that produces an unwanted effect is not important in the analysis (although it could be in the resolution of the unwanted effect).
post #176 of 254
Quote:
Originally Posted by Max_501
Not really. I already explained why I want to stay centered. Don't know why you are asking a question I already answered.
Because I think that there is more to it than you are seeing. That's why I asked the question the way that I did. If it offends, I'm sorry. That was not my intent. Perhaps I just need to step out of this discussion.
post #177 of 254
Quote:
Originally Posted by Max_501
Lets see if I'm picturing this correctly. Are you saying that if you put your right foot up on a block that is 4" high you can keep that leg perfectly straight while your left leg (on the floor) is also perfectly straight?
Yes. The differential is taken up by my right hip being 4" higher than my left.
Quote:
Originally Posted by Max_501
And if so then you can move your hips to the right of the right leg (so they are to the inside of a turn) and the left foot is still touching the ground in such a way that it could carry most of the weight in a turn?
Yes. In fact, it almost looks like a natural ski turn, since we often angulate with our hips. Of course, this only works for the relatively limited distance that I can create with just hip angulation. And I'm not saying that this is a common approach (it's much easier to flex that right knee). But, it is certainly an option available to us.
post #178 of 254
Thread Starter 
Quote:
Originally Posted by ssh
Because I think that there is more to it than you are seeing.
If you want to say something just say it.

I'll be crystal clear. I pull my free foot back to keep that inside ski from getting too far ahead of my outside ski which would put me in the backseat causing a recovery move or a fall. When I refer to being 'centered' it means my hips are (more or less) over my feet.
post #179 of 254
Thread Starter 
Quote:
Originally Posted by ssh
Yes. The differential is taken up by my right hip being 4" higher than my left.Yes. In fact, it almost looks like a natural ski turn, since we often angulate with our hips. Of course, this only works for the relatively limited distance that I can create with just hip angulation. And I'm not saying that this is a common approach (it's much easier to flex that right knee). But, it is certainly an option available to us.
How far apart are your feet when you do this exercise? I'm trying to reproduce it but without success.
post #180 of 254
Thread Starter 
Quote:
Originally Posted by ssh
I have see PSIman "ski". He exists. He "skis" on snow (and on a tilted table).
Well, lets see the video so we can see what he looks like on snow. I'll be honest that I'm skeptical about the likelihood of PSIMan skiing anything like that nice little animation.
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