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Flexion and extension patterns

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Chris V.

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I have integrated this into my beginner classes with great success. When the beginning student (low velocity) begins their turn with a conscious effort to "soften" the inside leg (while steering the outside), weight (mass) transfer to the outside ski happens laterally at the pelvis and is a result of the inside ski getting shorter not by purposely standing on the outside ski.

This is good. Most beginners and novices ski too tall and straight to begin with. That doesn't leave much range of motion for lengthening the outside leg! On the other hand, there's lots of room for shortening the inside leg. Also, most beginners and novices need to break out of the instinctive move of bracing on the inside ski to obtain what feels to them like a safe, wide base of support. This habit gets in the way of just about every possible aspect of improving form. You can tell a student to stand strongly on the outside leg. But not only does this flirt with creating proto-stemming habits, it also often doesn't work to break that bracing habit. The fault isn't really a failure to use the outside ski, so telling the student to use the outside ski more misses the mark. Better to go directly to the target and have the student soften the inside ski. This should promote a narrower stance and bringing the skis parallel.
 
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Chris V.

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Chris, I disagree with your initial premise. There is no need for different basic movement patterns for different snow conditions. 95% of the movements can be the same for all snow and terrain conditions. OK, maybe 93%. The difference can be as minor as most of the weight on the outside foot for packed snow vs. equal weight for deep snow. That’s about it.

Retraction/absorption turns handle every condition except jumping over an obstruction. Or just jumping for the joy of it.

Although I said that I thought there was room for more than one movement pattern depending on many factors, including snow conditions, it wasn't an assumption built into my basic question: "What do you advocate as the most functional pattern of flexion and extension through the turn cycle?"

To which you have given a clear answer.

Maybe I share your general preference for retraction/absorbtion turns. It appears that your preference is not shared by every frequent commentator on this site. It isn't shared by every trainer I've worked with.

I will say that in certain race situations, World Cup racers use turns built upon a strong extension at the transition. Perhaps this is necessary for achieving very rapid turn initiation at high speeds. Retraction turns do seem to be slower-developing, though very appropriate to a variety of all mountain free skiing situations.
 

Rod9301

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Although I said that I thought there was room for more than one movement pattern depending on many factors, including snow conditions, it wasn't an assumption built into my basic question: "What do you advocate as the most functional pattern of flexion and extension through the turn cycle?"

To which you have given a clear answer.

Maybe I share your general preference for retraction/absorbtion turns. It appears that your preference is not shared by every frequent commentator on this site. It isn't shared by every trainer I've worked with.

I will say that in certain race situations, World Cup racers use turns built upon a strong extension at the transition. Perhaps this is necessary for achieving very rapid turn initiation at high speeds. Retraction turns do seem to be slower-developing, though very appropriate to a variety of all mountain free skiing situations.
There is research showing that flex to release turns develop much faster than extension turns.
 

markojp

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Really slow it seems; Warren Witherell had this figured out in 1972.

Yes, because Warren knew all about 165 12-13r skis. They're pretty much the same as those 205's we skied on.
 

DavidSkis

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As one of my favourite coaches likes to say, we over-bend on easy terrain, and under-bend on difficult terrain.

To me, skiing is more of a continuum of movement whose timing and range you adjust based on the conditions, turn shape, speed, and your ability, rather than mechanical "patterns". All of the below is predicated on bending or extending enough to find balance in all planes.

My goal is to balance on the outside ski throughout the turn, but especially at the top of the arc. The pressure on the outside ski, in combination with tipping, steering, and bending or unbending the lower joints, creates the change of direction.

If I shorten my inside leg too much too soon, I'll lose the pressure against the outside ski. Poor change of direction, poor grip.

If I don't let my outside leg extend at the top of the turn, I'll still get a change of direction, but then I don't have a lot of range of motion to absorb the forces later in the turn.

If I extend my outside leg too much or flex the inside too much, I'm going to have a lot of pressure on the leg, and it may be too much for my physical conditioning for the pitch I'm on. E.g. short radius on a black run.

At lower speeds, there are less forces acting on the skier, so less range of motion is necessary. Extreme movements at lower speeds are more disruptive to the change of direction and momentum, or require a bit more mechanical counter-balancing. And I'd posit that's why you see more of the up movement and a taller stance at lower speeds on easier terrain. It lets the skier set up for the next turn without having to move through a squat.

But ultimately, I see flexion and extension more as a function of speed, pitch, and physical strength, rather than than patterns for x situation.
 

Doby Man

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Tip and pressure the ski to make it take you where you want to go. Works on antique 70-m SG skis. Works on modern 3-m SL skis. Only difference is in degree and timing.

The only difference that Witherell knew something that simply became even more relevant as ski technology advanced only means that he was a visionary. While his rationale of the importance of the medium of forces exchanged between the ski’s edges and base with the snow surface and the subsequent importance of how the ski is to be both tipped and pressured against the snow was as true then as it is now. This also places foot to boot pressure and ankle tipping next in line of importance before anything upper body related. While everything we do is systemically essential, this is about choosing a leading focus based on the chain of kinesthetic based proprioceptive priority. Today’s lively SL type skis only clarify that aspect even further.
 

James

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The only difference that Witherell knew something that simply became even more relevant as ski technology advanced only means that he was a visionary. While his rationale of the importance of the medium of forces exchanged between the ski’s edges and base with the snow surface and the subsequent importance of how the ski is to be both tipped and pressured against the snow was as true then as it is now. This also places foot to boot pressure and ankle tipping next in line of importance before anything upper body related. While everything we do is systemically essential, this is about choosing a leading focus based on the chain of kinesthetic based proprioceptive priority. Today’s lively SL type skis only clarify that aspect even further.
It's the "collision" of the body with the path of the ski that does most of the bending these days. The ski is set in an arc/path and the body collides with it on it's inside path to further bend the ski. So the ski is running into the skier/boot flexing the boot if the skier stays ahead and doesn't get thrown on the tails.
 

Loki1

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Another way of approaching the issue might be to identify what most intermediates use as their go-to flexion-extension pattern. With that information one could then identify which alternative flexion-extension pattern would open up for them the most potential for skiing more terrain and conditions safely and competently.

THis asumes that theire flexion/extension patterns are what are holding them back. I would say that most intermediate's flexion/extension patterns are the least of their concerns when trying to advance thier potential for skiing more terrain and conditions, safely and competently.

IMHO too many people are attributing too many things to flexion/extension movements. Essentially they are pressure control movements, that is all. They can control where(longitudinally) the pressure is created and when. They can effect lateral balance, but only in a wedge, when applied correctly. In a parallel stance, they are attributed to edging movements, however that happens through femur rotation and adduction/abduction. People need to stop concerntrating(teaching) on flexion and keeping the hip low through transition. These two movemenats are handcuffing most recreational skiers, not to mention thaere are being applied incorrectly, through misunderstanding of what truly is going on.
 
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Chris V.

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I would say that most intermediate's flexion/extension patterns are the least of their concerns when trying to advance thier potential for skiing more terrain and conditions, safely and competently. ...People need to stop concerntrating(teaching) on flexion and keeping the hip low through transition.

Well, keeping the hip low through transition is one pattern of flexion and extension, if only in contrast to alternatives of either a strong extension through the transition or a strong retraction through the transition. (One, zero, and minus one are all numbers, after all.) So thank you for your opinion, and I respect it. I'll just say that not everyone agrees.

I will say, however, that most beginners and novices, right up into many intermediates, are way too stiff in every dimension, including the vertical, and need to put a lot of focus into loosening up. They should learn flexion and extension, even if for no other purpose than adapting to variations in terrain.

And...some form of flexion and extension, of one leg relative to the other, is necessary to create a long leg short leg stance, and to get out of it through the transition.
 

JESinstr

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I will say, however, that most beginners and novices, right up into many intermediates, are way too stiff in every dimension, including the vertical, and need to put a lot of focus into loosening up. They should learn flexion and extension, even if for no other purpose than adapting to variations in terrain.

And...some form of flexion and extension, of one leg relative to the other, is necessary to create a long leg short leg stance, and to get out of it through the transition.

SO RIGHT.
If you subscribe to the concept of balancing through the arch, flexing and extending ankles, knees and hip joints is the number one new movement pattern a skier must learn. Unfortunately many instructors (be it through lack of knowledge or the pressures of time) fail to build this movement pattern to a sufficient level of competency in their students before moving on.
 

Doby Man

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It's the "collision" of the body with the path of the ski that does most of the bending these days. The ski is set in an arc/path and the body collides with it on it's inside path to further bend the ski. So the ski is running into the skier/boot flexing the boot if the skier stays ahead and doesn't get thrown on the tails.

I like the way you put it, James. It’s that “collision” that is created by tipping the ski aggressively and literally turning the ski “into” the side of the hill or, the “virtual bump” that represents the ground force reaction that picks your BoS up towards the CoM. This is much more effortless than when flexion is the downward movement of the CoM in the direction of the BoS in which the CoM has to be “picked up” to some degree within each and every turn in order to replenish that dropping motion. That is what flex to release ends up being due to the way it is timed and resulting in a “dropping” or “downward” moving CoM. When we use flexion in order to turn/tip/steer the ski, the timing of that flexion is based on where and when the skier wishes to turn and why there is no benefit of “up-force” from ground force reaction to “re-fund” that dropping movement. However, when we transfer that timing initiative to foot and ankle tipping, then the timing for flexion occurs naturally, effortlessly and from the bottom-up with the timing of that ground force “collision”. Because gravity effortlessly restores the function of “bottom-up” flexion we are then both creating and preserving energy through technique savvy rather than brute muscular effort. When we are skiing, we are much better off to reserve almost all our muscular effort to the calve muscles that control the foot and ankle simply because that is the part of the body that is directly “up against” the boot which directly transmits the intended tipping and pressure control to the ski that delivers the ski-to-snow interaction that is the hallmark of final cost/benefit outcome in the process of alpine skiing.
 

Nancy Hummel

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Most intermediate skiers use some variation of the same turning mechanism. Their flexion and extension pattern is necessary to describe this mechanism, but that alone doesn't fully describe the mechanism.

The typical intermediate mechanism for initiating a turn consists of an abrupt extension directed to the outside of the new turn, accompanied by an abrupt twisting of the full legs, or of the legs and the feet in the same direction. This leg turning is not of the kind that would produce strong early edge angles. The motion often appears as a small hop. It's a type of stem. There is often a sequential movement of the legs, with the new outside ski moving first, resulting in a small wedge at initiation--a classic stem. In other cases, the skis remain parallel, but there is still a deliberate, abrupt movement of weight onto the new outside ski accompanied by the abrupt extension. The result is a turn that starts in a skid and has a tight radius at the top, thereafter washing out into a longer radius, or into a nearly straight traverse. After the initiation phase, the skier's body is fairly static, with little change to the degree of flexion in the shaping phase.

There are at least of couple of alternative flexion-extension patterns in which this skier could be trained. Each would be a huge improvement. (In combination with changes to other aspects of movement patterns, of course.)

PSIA's recent emphasis on "getting pressure to the outside ski" has been over promoted and over used. It has been misinterpreted by many people and you end up seeing what you described. Unintended consequences.
 

James

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It’s that “collision” that is created by tipping the ski aggressively and literally turning the ski “into” the side of the hill or, the “virtual bump” that represents the ground force reaction that picks your BoS up towards the CoM.
Here's another on straight skis. He is not bending the tip as many believe is necessary to make a short turn or any turn. I'd agree the skis are tipped and steered agressively into the hill. The path of the body then collides with the skis and the knees go forward. What do we think of the reason for flexion here?
From Sybervision. Jens Husted or Chris Ryman
 

JESinstr

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PSIA's recent emphasis on "getting pressure to the outside ski" has been over promoted and over used. It has been misinterpreted by many people and you end up seeing what you described. Unintended consequences.

Nancy,
I would submit that this "misinterpretation" is due to a lack of knowledge and skill set to intentionally create and build turning force. Lacking the intentional creation of turning force leaves only gravity (one's weight) as a means of pressuring and bending the ski. Hence as @Chris V. stated, "the skis remain parallel, but there is still a deliberate, abrupt movement of weight onto the new outside ski ".

We shouldn't be getting pressure to the outside ski. Instead, we need to be doing things like flexion and tipping that BRINGS pressure to the outside ski. Having said that, we need to acknowledge that velocity is a key ingredient in creating turning force.

So this is why (IMO) intermediates are intermediates. Until they understand the concept and can learn to purposely execute the development of turning force (circular travel) they can't bust through the so called intermediate plateau.
 

James

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Call it what you want, people should be balancing on the outside ski. If you notice how you ski, this transfer happens pretty quickly, before turning forces.
Plenty of high level skiing can begin with lots of inclination to establish high edge angles btw. But balance is outside.
Ted:
IMG_4574.PNG

 

LiquidFeet

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@Doby Man, I'm going to rephrase what you just said, for the sake of my understanding. Tell me if I've got this right. Here's your post:

I like the way you put it, James. It’s that “collision” that is created by tipping the ski aggressively and literally turning the ski “into” the side of the hill or, the “virtual bump” that represents the ground force reaction that picks your BoS up towards the CoM. This is much more effortless than when flexion is the downward movement of the CoM in the direction of the BoS in which the CoM has to be “picked up” to some degree within each and every turn in order to replenish that dropping motion. That is what flex to release ends up being due to the way it is timed and resulting in a “dropping” or “downward” moving CoM. When we use flexion in order to turn/tip/steer the ski, the timing of that flexion is based on where and when the skier wishes to turn and why there is no benefit of “up-force” from ground force reaction to “re-fund” that dropping movement. However, when we transfer that timing initiative to foot and ankle tipping, then the timing for flexion occurs naturally, effortlessly and from the bottom-up with the timing of that ground force “collision”. Because gravity effortlessly restores the function of “bottom-up” flexion we are then both creating and preserving energy through technique savvy rather than brute muscular effort. When we are skiing, we are much better off to reserve almost all our muscular effort to the calve muscles that control the foot and ankle simply because that is the part of the body that is directly “up against” the boot which directly transmits the intended tipping and pressure control to the ski that delivers the ski-to-snow interaction that is the hallmark of final cost/benefit outcome in the process of alpine skiing.

Here's what I think you are saying:
After the fall line, the skier can direct the feet, skis attached, back up under the body ("turn the ski 'into' the side of the hill").
This involves continuing to tip the feet/skis so that they want to come back up toward the body ("tip/turn/steer the ski").
It also involves flexing/shortening the legs so the feet will move back up under the body ("use flexion").
Gravity and momentum are moving the body down the hill as this flexing/shortening/tipping happens, so the mass of the body moves toward the feet as they move toward the body. Gravity helps the two come together.
There will be minimal, if any, "collision" of the body and the feet at this point, because the ground-force reaction has been absorbed by the flexion.
There is no "up-force," or it's minimal, and it's not needed. The body with its momentum travels across the feet and the new turn happens "naturally,effortlessly."
The skier who does this uses less "brute muscular effort" in the turns, because the up-down movement is almost effortless. The skier floats through transition.

Yes? No?
 
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Doby Man

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Yes, I’d say that those words demonstrate a similar enough understanding. For this technique, both flexion and extension is an output from tipping and not a muscular input. Higher tipping and faster tipping is the key because that is what produces a higher degree of turn that gets you more ground force reaction with which to fund what is the largest bodily function of alpine skiing which is ankle/knee/hip or, “full body”, flexion. As well, when we tip the skis away from the falline in phase one, the ski “pulls” our feet away from the CoM for an effortless form of extension. Higher/faster tipping also eliminates the transition (finishiation) so that the skier is always carving which provides more time and space to control the forces given within the same overall length of turn and, as a direct result, is much more efficient and powerful. A “finishiation” takes away any straight line between arcs for better rhythm and a more rounded turn. Additionally, the higher degree of turn and more early (high “C”) carving from higher/faster tipping allows more speed control for steeper terrain in edge locked turns. Many people that can make RR tracks do not achieve enough degree of turn to get either much ground force reaction or speed control. High/fast tipping in edge locked turns forces the ski into action like the crack of a whip.
 

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DobyMan said: "High/fast tipping in edge locked turns forces the ski into action like the crack of a whip."

I must admit pulling up the new inside knee is how I get the crack of the whip action in cranked arc-to-acr turns. Tipping the ski sideways at the ankle accompanies that new inside leg flexion, as does extension of the new outside leg. For me (but maybe not you), conceptually, pulling up that knee is the conceptual key that works.

There are so many things the body is doing in such turns that must remain below conscious control in order to happen fast enough; one conscious thing is all my head can handle. There is drama in switching "high/fast" from high edge angle in one turn to the opposite high edge angle in the next turn. I have not yet figured out how to do it by focusing on ankle-tipping, which is a small range-of-motion movement. I'm not sure it would change the resulting turn in a good way; I get the crack-of-a-whip thing now with focus on the knee.

If I were a better skier, "go there" might be my conscious conceptual cue. Or even better, "two turns ahead of this one go over there." Don't know if I'll ever get to that point.

Why I'm saying this: different cues work for different skiers at different points in their development. Versatility is a prize; seeking to do things the way others do them is a good thing.
 
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Jamt

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DobyMan said: "High/fast tipping in edge locked turns forces the ski into action like the crack of a whip."

I must admit pulling up the new inside knee is how I get the crack of the whip action in cranked arc-to-acr turns. Tipping the ski sideways at the ankle accompanies that new inside leg flexion, as does extension of the new outside leg. For me (but not you), conceptually, pulling up that knee is the conceptual key that works.

There are so many things the body is doing in such turns that must remain below conscious control in order to happen fast enough; one conscious thing is all my head can handle. There is drama in switching "high/fast" from high edge angle in one turn to the opposite high edge angle in the next turn. I have not yet figured out how to do it by focusing on ankle-tipping, which is a small range-of-motion movement. I'm not sure it would change the resulting turn in a good way; I get the crack-of-a-whip thing now.

If I were a better skier, "go there" might be my conscious conceptual cue. Or even better, "two turns ahead of this one go over there." Don't know if I'll ever get to that point.

Why I'm saying this: different cues work for different skiers at different points in their development. Versatility is a prize; seeking to do things the way others do them is a good thing.
It is also very difficult to describe timing. High/fast tipping slows everything down and makes high edge angles impossible if you do it too fast/too early.
I find that often it is better to ask my skiers to try to delay edge engagement until the CoM is low enough, which coincides with high edge angles if you do it properly.
 

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