Dorsiflexion and its role in skiing

James

Skiing the powder
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Are you saying that you keep flexing your legs in a turn as the turn forces increase?

I do the opposite, i straighten my leg as the forces increase, to better resist them.

Then in transition, i flex my legs to release
Well it's possible.
These guys prob often have a very short long phase and then they're into the front of the boot as the skis come around.
These guys do extension, retraction, and neither at transition. Meaning just go over. They don't always get real straight for the forces. Two are wcup globe winners.
I'm not sure you could film more and show less skiing, but Salomon tried.

Skiing after 0:35.
 

JESinstr

Lvl 3 1973
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Are you saying that you keep flexing your legs in a turn as the turn forces increase?

I do the opposite, i straighten my leg as the forces increase, to better resist them.

Then in transition, i flex my legs to release
I allow my outside leg to work in a strong flexed position not straight. A straight leg leaves few options in the dynamic environment. It is the inside leg that is more actively flexing in order to enable higher edge angles.

Why would you resist the force that is trying to push you into the turn? That's the force your technique is trying to build. That's your friend!
You build and regulate the force through edging skills and pressure management and of course, proper balance.

On second thought, maybe what you perceive as straightening may be your moving inside the turn but make no mistake, you are able to move inside because you are being pushed by a force other than Gravity.

If you flex to release, that's ok the leg is very capable of substantial vertical travel for the application and release of pressure.
 

geepers

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To drive your foot into pronation- Weight the inside foot just before/during transition. Inside foot on little toe side. When you release and extend that leg, boom, pronated, on big toe edge and carving.
That early transfer of weight to the inside foot - beginning shortly after the fall line - became my go-to

JF is a vastly better interviewer than Tom G. He listens, recreates what was said, and brings up relevant and interesting questions that get more out of the subject. He'll also remember things and bring them up again.
Gellie in his interviews will often say things like "right...", "yeah..." in a way that could be interpreted as "hurry up and move on". In person, it would be really poor form. In the skype world he kind of gets away with it. But, kudos for doing them at all.
His thing on the foot is somewhat muddled, but that's the issue with off the cuff speaking. It would be much better in writing because you can see what you've said and if it'ts really what you want to communicate.

Here's a video on the ankle. Lots of medical terms. Settles the definition though. In closed chain kinematics, foot on the ground, dorsiflextion is the limb moving towards the foot.

I can't picture -the axis of the ankle of 82deg in the sagital plane? Seems too high.

Good vid find. Commentary has been through one of those "how to compress 15 minutes into 7 without sounding like a chipmunk" software programs.

Question: Are our feet in full closed chain? Seems to me it depends. Feet lightly loaded or in the air - no. Even if loaded to some degree there's a some freedom of movement fore/aft along the direction of the ski.

One thing I did try to work this past season was the sub-talar joint. It felt like a small inwards roll of the foot at the heel. Everything else being equal it seemed to produce that bit extra turn performance.
 

James

Skiing the powder
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Joined
Dec 2, 2015
Posts
9,207
That early transfer of weight to the inside foot - beginning shortly after the fall line - became my go-to



Good vid find. Commentary has been through one of those "how to compress 15 minutes into 7 without sounding like a chipmunk" software programs.

Question: Are our feet in full closed chain? Seems to me it depends. Feet lightly loaded or in the air - no. Even if loaded to some degree there's a some freedom of movement fore/aft along the direction of the ski.

One thing I did try to work this past season was the sub-talar joint. It felt like a small inwards roll of the foot at the heel. Everything else being equal it seemed to produce that bit extra turn performance.
Closed chain- probably if there's weight on it, but how much? don't know. Inside ski likely foot is open chain unweighted.

So I found out what the effect of lifting the big toe I was describing earlier. It's called the "windlass mechanism". Actually involves all the toes. Tightens the plantar fascia, inverts/supinates the foot, and locks tbe subtalar joint. In walking, it turns the foot into a rigid lever at push off from stance. Apparently some people don't have this, but normally that's what happens.

Since you're just lifting the toesas opposed to pushing off the ground after the stance phase, the effect is likely less. Don't know.
It's not the thing you'd want to do if you're rotating the tibia in to every/pronate the foot as in Tom G's video.
The foot certainly is complicated.
 

no edge

Getting on the lift
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May 17, 2017
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JF is a vastly better interviewer than Tom G. He listens, recreates what was said, and brings up relevant and interesting questions that get more out of the subject. He'll also remember things and bring them up again.
Gellie in his interviews will often say things like "right...", "yeah..." in a way that could be interpreted as "hurry up and move on". In person, it would be really poor form. In the skype world he kind of gets away with it. But, kudos for doing them at all.
His thing on the foot is somewhat muddled, but that's the issue with off the cuff speaking. It would be much better in writing because you can see what you've said and if it'ts really what you want to communicate.

Here's a video on the ankle. Lots of medical terms. Settles the definition though. In closed chain kinematics, foot on the ground, dorsiflextion is the limb moving towards the foot.

I can't picture -the axis of the ankle of 82deg in the sagital plane? Seems too high.

Is that a foot?
 
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