A serious post ; foot initiation and CM movement at High-C

[jclayton]

Those SkiCanada articles have dreadful , contradictory , confusing explanations . J P Roy simply shows good retraction and free foot tipping , I can't see any steering at all etc...

There would be no time to ski the skis ( i.e. steer ) or think about crossunder , these are things we see as observers , surely the physical cue for the skier is retract/relax and tip . A cue that can be directly applied physically and without cogitation .

My feet are not " thinking " steer , crossunder I definitely feel them " thinking " relax , tip . My brain , when it gets in the way , is thinking duh!! I'm, crossing under/ over , what a heroe , then it usually all falls apart .

All these observed aspects of skiing are fine for ski theorists but I just want to get down and do it . All they end up doing is cloud the issue .

[John Mason]

Question 2 - musings

Interesting, pull downhill leg up, Newton says body comes down. If body is being resisted by uphill ski, would that seem to make the body move aggressively across that downhill leg.

I will add, that if you have more flexion in the legs, you can tip more. When I'm about to do very short radius turns, I drop a tad lower in my stance to enhance the tipping. But that's an interesting point you brought up. The SP with agressive flexion of that down hill ski and tipping is a strong move. You may have hit one aspect of why this combination works so well when you need a very quick transition.

Now I'll shudup and listen.

[skisalot]

John Mason says, "Now I'll shudup and listen".

I will believe that when I see it.[/quote]

[BigE]

jclayton:

I don't see any free foot tipping, and I don't know how you can, when the free foot is completely obscured in the montage. IMO, the analogy to inline skating might indicate that no free foot tipping was used.

Certainly there is no time to thing about cross-under. There is only time to drive/point the skis into the intended direction. The explanation identifies the skiers use of edging to do just that.

The point was not to start a religious war. It was merely intended to show a pictorial example of what a cross-under looks like, FOR THOSE THAT WERE INTERESTED in the term. I NEVER suggested how you should do it, just attempted to clarify the definition of the term. If you don't like the term, or if it clouds your mental image, feel free to ignore it.

Back to reality:

What I wanted to show is that you can play connect the dots with J.P. Roys helmet, and see that they form a straight line, yet the inclination of the body from one turn to the next has changed. That indicates cross-under.

Cheers!

[jclayton]

Hi BigE ,
thought I might get a bite on that post . If you check , I just said tip , not free foot tip , though from what Ive seen of slalom skiers it is almost a given . I couldn't perceive it in the montage either .

I don't agree that there is much analogy to inline skating where much less ( virtually none ) effort is needed to tip .

How can you point/drive (steer) the skis when they're on such an extreme edge , wouldn't you need rotational input to do this . I can't see that in the montage

The only war I'll wage is against bad use of our language and there is certainly some very furry language use in those articles . Don't they have a proof reader ?

I honestly don't think there is any time to drive/point the skis in this case , the power from the skis would surely not allow it . You would be hard put just to tip them in time for the next turn .

I agree , it is a nice example of " crossunder ".

[piggyslayer]

Why did I post this stupid question about crossover and crossunder



John, thanks for looking at my question 2, I think I have confused everyone with Sir Newton. Sure flexing legs adds to CM momentum, no question about that. My question is purely about technique of correct flexion.
I notice on Harb Carvers that if I do not let the balance to go aft and flex aggressively, I use my abdominal muscles a bit and my torso leans forward a bit (not on purpose). Question is if this should be resisted or this is OK.

Two ways to flex, relax quads (balance moves aft a bit) or pull knees up (balance moves a bit fore and torso moves forward a little bit).
I believe the relaxing quads is better, but is the other approach bad?

Robert

[Guest]

It's two in the morning here...... my hockey game is over, (we won!), as are the obligatory brown pops...

Cross-under is defined as skis crossing under CM, cross over is defined as CM crossing over the skis. Notice that the definitions are not very good from the logic standpoint. Since they imply relative movement of CM and skis, by the above definitions of crossunder and crossover are actually the same thing.

It seems a bit cloudy because when you change the "frame of reference" within which you observe the move, you can call it either. But you are really doing only one or the other. It looks like you are saying that there is no real distinguishing characteristic.

As J.P Roy is demonstrating, you see the relative stability of his center of mass, the skis move under him; it's a nice cross-under move. This can in no way be confused with a cross-over, unless you are looking at it from the frame of reference of the feet, and assume they are not moving. But the feet are moving on a distinctly differnent path and more importantly, they are not doing so because they were dragged on edge by the crossing over of the CM.

If you thought JM was geeky move over pal!

Anyhow, perhaps the definition should state that in Cross-over, the CM is primarily responsible for dragging the skis onto a new edge, while in cross-under, they are guided onto the new edge by foot/leg actions alone.

Does that help at all?

jclayton: You mentioned free foot tipping in the first paragraph of your post. How could I know it was a typo?

Cheers!

[jclayton]

Quite right ,
I should proof read my posts a bit better

[BigE]

Two ways to flex, relax quads (balance moves aft a bit) or pull knees up (balance moves a bit fore and torso moves forward a little bit).
I believe the relaxing quads is better, but is the other approach bad?

Robert

I too believe that relaxing the quads is better. I believe that's a matter of biomechanics -- when you are retracting the knees, the muscles go into concentric contraction. What this means is that you are less able to determine the exact position of your feet. Bear with me on this, and I'll complete this really weird thought:

Suppose you are in a grocery store, and want to buy an apple. You pick one up, and raise it and lower it in one hand, gently relaxing and tensing the arm in an attempt to find one with just the right weight. The arm muscles move from concetric (raising the apple) to eccentric (lowering) contractions. At what point do you get enough information to determine it's weight? Exactly at the point where the muscles go from eccentric to concentric contraction (or vice-versa). At that point, more muscles are in use, so the body has more feedback.

Contrast that to holding the apple with a death grip, and stock still -- really tense up! The weight almost vanishes!

So this analogy is all about eccentric/relaxing and contracting being able to provide more feedback about what the body is doing, than contration alone. So relaxing the quads will tell you much more about what you are doing (foot position/balance etc) than retracting the knees will tell you.

Also, since the retraction has momentarily stopped the feedback circuits in the body from working optimally, there is a momentary delay in reestablishing just what the body is doing after you begin to relax again.

This is what I like to think of as the uncertainty principle: The more certain you are of the bodies location, the less strongly you can move it.

Conversely,the more strongly you move the body, the less certain you are of it's location.

Smoothness and grace in movement is very desireable. Stiffness and force are not....

SO, IMO, knee retraction is a less desireable form of flexion.

Also, and this is pure conjecture, you may find your balance point moving back on the blades (and the resulting mini-goodmorning) as a result of the stiffness of the boots, and the impossibility of applying as much forward pressure as you could if you had the shovel of the ski to press into.....I have found that inline skates are soft enough to allow the ankle to bend when I do that flexion by relaxing in inline skates; the balance point does not move back, requiring the "good morning" posture.

Anyway, that's my 2 cents!

[piggyslayer]

Thanks BigE.
I agree with all that you said.

A small comment based on what I still remember from last season. I noticed that soft skis on icy terrain provide interesting feedback.
I had to follow each turn more. The end of the turn was working for me better if I actively flexed legs as opposed to relaxed my quads.
Relaxing quads has (at least for me) an effect of reducing the edge.
Flexing by pulling up the knees worked by reducing the pressure on the skis (which were about to loose grip and start to slip) but at the same time the skis were continuing to cut the ice. I was more effective this way in active adjustments I needed to do to stay in my tracks. Maybe that is just me, but this is what I remember.

My current understanding is that a little ?good morning? is OK if it is result of flexing leg and is not initiated by the upper body.
I think that letting the balance go a bit aft by not doing ?good morning? is superior way to ski. I try to do both. I tried both on Harb Carvers and both ways worked for me, but without ?good morning? is more scary ? skating on the edge of balance.

Robert

[BigE]

My current understanding is that a little ?good morning? is OK if it is result of flexing leg and is not initiated by the upper body.
I think that letting the balance go a bit aft by not doing ?good morning? is superior way to ski. I try to do both. I tried both on Harb Carvers and both ways worked for me, but without ?good morning? is more scary ? skating on the edge of balance.

Robert

I'd suggest that you keep the good morning. Or perhaps loosen the cuffs of your boots to get a little more ankle flexion? I worry about training the body to get into the back seat now, so that when ski season arrives, you've got a lot to unlearn.

A friend of mine, (CSIA level III and CSCF level II - that's a mid level coach btw ) suggested that I dedicate a pair of boots to the blades and have them "softened" by a bootfitter, else I'll learn to ski in the back seat

[piggyslayer]

BigE,
that is strange, I find it hard to be in back seat on Harb Carvers.
If I relax my quads to release I may feel pressure in my heels but not against my calf.
The turn I am describing does not go aft too far, the rule of thumb is that I should never feel contact with the boot, I can feel pressure on my heels.
The position is easy to recover from and I catch up with it in the upper part of the turn.

Here is why I do that. For long time I was after bending the ski in the upper part of the turn. The way I learned to do that is by applying fore balance early in the turn by pulling on hamstrings. It is easy to overdo it. If the pressure is applied to fast before skis are engaged the tail will skid. The solution for this problem for me was to delay this process by a tab. To delay I simply flex by relaxing, pressure in heels, and hold the position for a moment. This allows the edges to set before to much force is applied and I hold to my tracks better this way.

By the way, if you look at some pictures of Harald skiing he is often releasing with flexed legs and minimally aft balance. Look at this picture posted on Jay?s website:
http://web.pdx.edu/~petersj/HoodCamp/Ge ... MG0028.JPG

[BigE]

BigE,
that is strange, I find it hard to be in back seat on Harb Carvers.
If I relax my quads to release I may feel pressure in my heels but not against my calf.
The turn I am describing does not go aft too far, the rule of thumb is that I should never feel contact with the boot, I can feel pressure on my heels.
The position is easy to recover from and I catch up with it in the upper part of the turn.

In my world, that is the back seat -- so is the picture of HH! Pressure on the calf is the trunk! I've done those same turns both on the carvers and on snow. I don't like skiing in the back seat at all, so I've dropped using the carvers on anything that flat. I relegate their use now to much steeper "slopes".

Here is a link to something called "Bode's secret", in which he gets the edges of the tails to engage from the back seat, and then corrects into the belly of the turn. What it's about is the CM taking the shortest path.
From your descriptions, I think the montage here shows exactly the two different approaches: Aarnodt shows a bit of a good morning, Bode is in the back seat....

http://www.skimag.com/skimag/instructio ... 72,00.html

Interesting similarity isn't it?

[piggyslayer]

Very interesting.
Pressure in the heels during ?float? is not always what I feel brave enough to do, but out of my 3 body to asphalt collisions this year, none was caused by trying this maneuver.

For me being in back seat implies pressure on the calf. Pressure on the heel is acceptable.
Also, you got to load/ride the ski tail at the end of the turn, or the 2 big 100mm wheels on the Carver, that is what fun is about.

Digression, quote from the linked article:

Keep your skis shoulder-width apart for stability and strive to incline and angulate to achieve more edge angle

I do not see Bodie skis being shoulder wide. I would say this is a narrow stance if I ever seen one. What are some of us with broader shoulders to do? Quit skiing or damage the knees?

Robert

[milesb]

BigE, the tips rather than the tails are still engaging at the start of the turn through a movement that momentarily puts pressure on the front of the ski.(I can't accurately describe the mechanism) The key is to get the skis turning quickly enough so that they slow down enough for the body to catch up. Note that if the skis skid very much or don't make a short enough arc, the skier ends up in the backseat and probably will go down. Which makes it a bad move for some gates. But you probably already knew all that!
What's really amazing is when the skis catch a little air in the transition and the racers still make the next turn.