Question for the Ortho experts

[Sherman89]

How much edge angle can a athletic generate with ankle flexion only, question 2– how much edge angle can be generated by knee flexion only?

 

[Jilly]

As an instructor - none. You need to tip the skis. Flexion is only a forward force. Back to this thread - https://www.skitalk.com/threads/tipping-the-foot-inside-the-boot-first-why.28245/

 

[Andy Mink]

I suppose, in theory, you would only need to tip your entire body without flexing ankles or knees. You could do that with straight legs. The result might not be very pleasant though.

 

[pchewn]

I suppose, in theory, you would only need to tip your entire body without flexing ankles or knees. You could do that with straight legs. The result might not be very pleasant though.

Here is Stein Eriksen getting edge angle without flexing ankles or knees. The result is pleasant.

 

[Henry]

Knee angulation causes edging by one flexing the knee then internally rotating the leg in the hip and ankle joints. The debate on whether this is a good movement resides in other threads.

If one wants the greatest edge angles, ski much like this guy...Ted somebody.

Note what he's doing...most of his weight on the outside ski, inside foot up next to his outside knee, outside knee slightly bent & rotated inward for more edge angle, hips near the snow, body countered (his skis are going right while his chest points left) with his inside shoulder ahead of his outside shoulder, body deeply angulated (bent at the waist) with the counter facilitating more angulation.

 

[Jilly]

Showing his bases to the squirrels, or the trees, or the rocks...whatever...

 

[Sherman89]

Let me me rephrase the question: how many degrees of edge angle can be generated by rolling the skis on edge with ankles only? Second question which has not been answered : how many degrees of edge angle can be generated by the offset of the knees from vertical?

 

[Andy Mink]

Here is Stein Eriksen getting edge angle without flexing ankles or knees. The result is pleasant.

View attachment 191748

I meant if *I* did it that way the results wouldn't be pleasant. At least for me. Others may find it humorous!

 

[slidingmike]

@Sherman89 you may want to clarify your second question. What does "offset of the knees" specifically mean to you? Rotating them inward with a combination of somewhat flexed knees, rotating the ankles, and rotating the hips? Or simply closing the knee joint in its primary axis?

 

[Sherman89]

@Sherman89 you may want to clarify your second question. What does "offset of the knees" specifically mean to you? Rotating them inward with a combination of somewhat flexed knees, rotating the ankles, and rotating the hips? Or simply closing the knee joint in its primary axis?

Seems that there is always a challenge of words when we describe a movement, my question is what is the maximum ski angle generated by knee flexing or lateral knee movement to create ski edging.

 

[Jilly]

If by flexion of either, you're meaning bending in a forward motion, then none. Edging and edge angles are tipping the feet, and moving the COS inside the arc the of the turn with angulation to maintain balance. So that maybe what you are calling "lateral knee movement".

 

[Sherman89]

If by flexion of either, you're meaning bending in a forward motion, then none. Edging and edge angles are tipping the feet, and moving the COS inside the arc the of the turn with angulation to maintain balance. So that maybe what you are calling "lateral knee movement" Let’s get back to basics, describe how to tip your feet?

 

[Sherman89]

Let’s get back to basics, how do you tip your feet and what joints are you using?

 

[Chris V.]

Let me me rephrase the question: how many degrees of edge angle can be generated by rolling the skis on edge with ankles only? Second question which has not been answered : how many degrees of edge angle can be generated by the offset of the knees from vertical?

Not hard to measure. Stand still on a flat spot, skis on. Tip feet over as far as you can, keeping hips over feet. Have friend see how far your bases have tipped from horizontal.

This is an essential basic skill, valuable for initiating movements and fine tuning. But my trainers argue that knee angulation is a biomechanically weak movement to rely upon too heavily. We need a healthy dose of hip angulation. And of course inclination accounts for the lion's share of edge angles.

 

[Sherman89]

Not hard to measure. Stand still on a flat spot, skis on. Tip feet over as far as you can, keeping hips over feet. Have friend see how far your bases have tipped from horizontal.

This is an essential basic skill, valuable for initiating movements and fine tuning. But my trainers argue that knee angulation is a biomechanically weak movement to rely upon too heavily. We need a healthy dose of hip angulation. And of course inclination accounts for the lion's share of edge angles.

My question —-what is the angle for the ankle roll and the knee roll and all I get is a bunch of chatter, I did not ask about hip anything. No one seems to know the answer.

 

[Chris V.]

My question —-what is the angle for the ankle roll and the knee roll and all I get is a bunch of chatter, I did not ask about hip anything. No one seems to know the answer.

Look, it's not going to be identical for all skiers. There's individual anatomy. But can be measured for an individual, for what it's worth.

 

[James]

It’s not much before the tibia inclines. I’d guess 5-10 deg. Probably the lower end.

ps-using “ortho experts” will get you next to no responses if you have to hold to that.

 

[Andy Mink]

My question —-what is the angle for the ankle roll and the knee roll and all I get is a bunch of chatter, I did not ask about hip anything. No one seems to know the answer.

We must be missing your question. The knee (and ankle when in a boot) can only move fore and aft. Any lateral movement must come from the hips or the entire body tipping and if the whole body tips with no hip or lateral knee movement pretty soon you'll be on one outside edge with the other ski off the snow.. Yes, the knee can bend and move inward or outward but that's an effect of the hip.

Let’s get back to basics, how do you tip your feet and what joints are you using?

Your hips give lateral movement. Sit in a chair with your boots on. Tip your boots to the inside and outside "edges". Your ankle and knee remain at the same angle, your hip provides the movement. Yes, the knee moves in or out of the vertical plane but it doesn't change its angle relative to the femur and tib/fib.

 

[KingGrump]

My question —-what is the angle for the ankle roll and the knee roll and all I get is a bunch of chatter, I did not ask about hip anything. No one seems to know the answer.

Perhaps the question is not worth entertaining.

 

[Fuller]

Perhaps the question is not worth entertaining.

I dunno 'bout that... but I'm easily amused.