Ankle Flexion--Active or "Passive"?

[Rdputnam515]

So dorsiflexion can help maintain tip pressure, whilst also keeping the tips up!?

It keeps them from diving uncontrollably and darting all over the place. dorsiflexion keeps the tips oriented properly and helps the ski work properly. The shovels will then flex and push on the snow properly.

after all you will be pulling the toes and therefore the ski tip towards the body

try skiing pow or chop without it, tell me how it goes

 

[Skitechniek]

To increase pressure on the tip you need to increase pressure on the cuff. It's a tool in the toolbox.

What I have been trying to explain is that this is not true and that is not a matter of opinion, but something that has been researched. Increasing pressure on the cuff does nothing for increasing the pressure on the tip. Moving your CoM forward is what increases pressure on the tip. Cuff pressure and tip pressure is correlation, moving the CoM forward and tip pressure is causation.

Saying cuff pressure causes tip pressure is the same as saying more ice cream sales leads to more shark bites. When more shark bites happen, more ice cream gets sold because it is warm outside and therefor a lot of people go to the beach. Because there are a lot of people at the beach, a lot of people will go in the water and because there are more people in the water it is more likely someone will get bitten by a shark. More people in the water due to warm weather and more shark bites is causation. More ice cream sales and more shark bites is correlation. Same logic applies to cuff pressure and tip pressure. If you have more tip pressure, that is because your CoM has moved forward. And because your CoM has moved forward you feel more shin pressure. The forward CoM and tip pressure is causation, the shin pressure and tip pressure is correlation. If I ski with my boots unbuckled and move my CoM forward I will have the same amount of tip pressure and no cuff pressure.

So to make things clear, I am not arguing against cuff pressure, I am just saying that it correlates to good skiing, but it doesn't CAUSE good skiing.

 

[jimtransition]

It keeps them from diving uncontrollably and darting all over the place. dorsiflexion keeps the tips oriented properly and helps the ski work properly. The shovels will then flex and push on the snow properly.

after all you will be pulling the toes and therefore the ski tip towards the body

try skiing pow or chop without it, tell me how it goes

If you want to think that, feel free. I can't really dorsiflex, and don't try to, but I still ski powder just fine.

 

[Rdputnam515]

If you want to think that, feel free. I can't really dorsiflex, and don't try to, but I still ski powder just fine.

do you create tension at all in your tibialis anterior? Even if it’s an isometric contraction?

this is what I am referring to.

if not I, I would think controlling your skis would be difficult.
this is my take on the situation

 

[razie]

So dorsiflexion can help maintain tip pressure, whilst also keeping the tips up!?

Thus ensuring tail pressure?

 

[razie]

What I have been trying to explain is that this is not true and that is not a matter of opinion, but something that has been researched. Increasing pressure on the cuff does nothing for increasing the pressure on the tip. Moving your CoM forward is what increases pressure on the tip. Cuff pressure and tip pressure is correlation, moving the CoM forward and tip pressure is causation.

Saying cuff pressure causes tip pressure is the same as saying more ice cream sales leads to more shark bites. When more shark bites happen, more ice cream gets sold because it is warm outside and therefor a lot of people go to the beach. Because there are a lot of people at the beach, a lot of people will go in the water and because there are more people in the water it is more likely someone will get bitten by a shark. More people in the water due to warm weather and more shark bites is causation. More ice cream sales and more shark bites is correlation. Same logic applies to cuff pressure and tip pressure. If you have more tip pressure, that is because your CoM has moved forward. And because your CoM has moved forward you feel more shin pressure. The forward CoM and tip pressure is causation, the shin pressure and tip pressure is correlation. If I ski with my boots unbuckled and move my CoM forward I will have the same amount of tip pressure and no cuff pressure.

So to make things clear, I am not arguing against cuff pressure, I am just saying that it correlates to good skiing, but it doesn't CAUSE good skiing.

Maybe we can use sharks to teach forward - by tying them to the skier, having them follow closely behind?

Agree on forward vs shins. The tongues add an element of torque, but they're not the entire story. Having the hips forward of the heels is the critical bit.

 

[dj61]

Cuff pressure and tip pressure is correlation, moving the CoM forward and tip pressure is causation.

Wow that sounds scientific but is nonsensical.

 

[Sanity]

What I have been trying to explain is that this is not true and that is not a matter of opinion, but something that has been researched. Increasing pressure on the cuff does nothing for increasing the pressure on the tip. Moving your CoM forward is what increases pressure on the tip. Cuff pressure and tip pressure is correlation, moving the CoM forward and tip pressure is causation.

Saying cuff pressure causes tip pressure is the same as saying more ice cream sales leads to more shark bites. When more shark bites happen, more ice cream gets sold because it is warm outside and therefor a lot of people go to the beach. Because there are a lot of people at the beach, a lot of people will go in the water and because there are more people in the water it is more likely someone will get bitten by a shark. More people in the water due to warm weather and more shark bites is causation. More ice cream sales and more shark bites is correlation. Same logic applies to cuff pressure and tip pressure. If you have more tip pressure, that is because your CoM has moved forward. And because your CoM has moved forward you feel more shin pressure. The forward CoM and tip pressure is causation, the shin pressure and tip pressure is correlation. If I ski with my boots unbuckled and move my CoM forward I will have the same amount of tip pressure and no cuff pressure.

So to make things clear, I am not arguing against cuff pressure, I am just saying that it correlates to good skiing, but it doesn't CAUSE good skiing.

That is not true. It's torque, physics 101. Do the static force equations. For a simple experiment, ski straight in deep powder, crush the cuff, and see what happens. Torque is applied to the front of the ski, and the ski will nosedive. If you lean against the cuff of the boot, with sine of the forward lean angle, you'll get a torque applied which means you must rotate unless there is a reaction force. The reaction force isn't from the tail of the skis or under the boot. It's from the front of the ski. If there's adequate support in front of the boot, but no support under the tip, then the reaction force will come from the ski just in front of the bindings and not from the tip, i.e. there won't be increased force on the tip. But, in cases where there isn't adequate support until the tip of the ski, then the tip of the ski will have more force applied to it. Skiing in powder for example, the powder doesn't provide enough support under the ski near the binding. If you had super short skis, the skis would just nosedive with hardly any effort. It takes the long ski with lots of surface area and torque to provide the support largely at the fat tip. So, in powder you can feel the effects right away, because the tip will nosedive with cuff pressure. Leaning against the cuffs provides torque that must be supported by the front of the ski. Where the pressure is along the front of the ski depends on the circumstances. To some extent, "the tip" is just a metaphor for the front of the ski. Sometimes the action will be up around the widest part of the ski. Sometimes it will be closer to the boot, but in every case, cuff pressure increases pressure on the active portion of the front of your ski.

 

[Skitechniek]

That is not true. It's torque, physics 101. Do the static force equations. For a simple experiment, ski straight in deep powder, crush the cuff, and see what happens. Torque is applied to the front of the ski, and the ski will nosedive. If you lean against the cuff of the boot, with sine of the forward lean angle, you'll get a torque applied which means you must rotate unless there is a reaction force. The reaction force isn't from the tail of the skis or under the boot. It's from the front of the ski. If there's adequate support in front of the boot, but no support under the tip, then the reaction force will come from the ski just in front of the bindings and not from the tip, i.e. there won't be increased force on the tip. But, in cases where there isn't adequate support until the tip of the ski, then the tip of the ski will have more force applied to it. Skiing in powder for example, the powder doesn't provide enough support under the ski near the binding. If you had super short skis, the skis would just nosedive with hardly any effort. It takes the long ski with lots of surface area and torque to provide the support largely at the fat tip. So, in powder you can feel the effects right away, because the tip will nosedive with cuff pressure. Leaning against the cuffs provides torque that must be supported by the front of the ski. Where the pressure is along the front of the ski depends on the circumstances. To some extent, "the tip" is just a metaphor for the front of the ski. Sometimes the action will be up around the widest part of the ski. Sometimes it will be closer to the boot, but in every case, cuff pressure increases pressure on the active portion of the front of your ski.

Let's agree to disagree.

 

[Sanity]

Let's agree to disagree.

Let's agree that you're wrong.

 

[Rdputnam515]

Thus ensuring tail pressure?

No, only if you shift COG rearward, COG movement forward moves pressure to the tips.

right?

again just trying to think through the physics here. Someone needs to draw a Force diagram here lol.

then we could parse that out into biomechanics ha

 

[razie]

Cuff pressure and tip pressure is correlation, moving the CoM forward and tip pressure is causation.

I kind'a like that.

It's true that usually cuff pressure is associated with tip pressure, with exceptions, for instance at the end of the turn, where you have this conundrum of being on the tails but flexing the cuff... although, I guess it still is better than being on the heels and loosing the skis from under you.

But if the hips are not forward of the heels, cuff pressure won't really work. You can dorsiflex all you want with the TAs, but there is no body to add the weight necessary.

On the other hand, if my hips are forward, I can even "pedal" (push toes down, which opens the ankles) and still manage to pressure the tips.

So being "forward" is overall more important than being on the cuffs, although usually associated to it.

 

[LiquidFeet]

I kind'a like that.

It's true that usually cuff pressure is associated with tip pressure, with exceptions, for instance at the end of the turn, where you have this conundrum of being on the tails but flexing the cuff... although, I guess it still is better than being on the heels and loosing the skis from under you.

But if the hips are not forward of the heels, cuff pressure won't really work. You can dorsiflex all you want with the TAs, but there is no body to add the weight necessary.

On the other hand, if my hips are forward, I can even "pedal" (push toes down, which opens the ankles) and still manage to pressure the tips.

So being "forward" is overall more important than being on the cuffs, although usually associated to it.

I would like to like this twice.

 

[markojp]

Razie, you ever telemark?

 

[razie]

Razie, you ever telemark?

No, but i am very seriously looking at getting an AT setup.... assuming it can also do tele? I need to stat reading on this more.

I know that you can shove the inside foot way back

Huh. Interesting. Do racers that carve'm also not extend the outside leg? Are the cuffs softer or how does that work? Asking for a friend.!

Watched a couple races and see no tip pressure to speak of



I see generally little angles and little tip use? I am gowing more and more anxious...

 

[markojp]

No, but i am very seriously looking at getting an AT setup.... assuming it can also do tele? I need to stat reading on this more.

I know that you can shove the inside foot way back

Huh. Interesting. Do racers that carve'm also not extend the outside leg? Are the cuffs softer or how does that work? Asking for a friend.!

Watched a couple races and see no tip pressure to speak of

View attachment 155737

I see generally little angles and little tip use? I am gowing more and more anxious...

View attachment 155738

Not even on the inside ski? (Teley turns in AT gear isn't anywhere near the same or as effective with a bellowed boot that keeps the ball of the foot on or near the surface of the ski.)

Honestly, I'm not super interested in Teley racing. The length of the stance is in the rule book, and IMHO, not particularly optimal for snow/ski outcomes and tactical choices, but that's just me.

 

[razie]

Not even on the inside ski? (Teley turns in AT gear isn't anywhere near the same or as effective with a bellowed boot that keeps the ball of the foot on or near the surface of the ski.)

Hmm. Ok. Is there an option for AT bindings with Teley boots sort of? Two birds one stone kind'a deal...? Don't bother answering - I'll look it up thanks for the insight.

 

[Henry]

"If I have a boot that is gas pedaled, hence already putting me into a more dorsiflexed position, does that create a less-desirable platform for active dorsiflexion?"

Amy, the supposition is wrong. The goal is to get the body's center of mass over the sweet spot on the skis, somewhere forward of the toe binding. It is not about ankle bend angle,* nor pressure against the boot tongue nor pressure on the toes or ball of the foot. You may need changes to the boot shaft angle--tilt the cuff forward-- or changes to the binding delta angle--shim under the heel binding**--or a spoiler between the cuff and the back of the liner. A small number of people benefit from a heel pad. Some people need to do adjustments in the opposite direction--we're each an individual. You really need a visit to a good boot alignment person. Not all good boot fitters are also good at alignment.

Dorsiflexion works for skiers who are close to being properly balanced and can pull themselves the small amount needed to get where they want to be. The tibialis anterior muscles are relatively small and weak. They can do a little. Pulling the skis back under the skier uses the big strong hamstring muscles and is much more effective. The shin pressure against the cuff is your gauge to know where you are. When a certain pressure there happens and you ski great, you know to return to that pressure. Pull the skis back until the body center of mass is over the skis sweet spot, feel the shin pressure you know works for you, and you'll ski great. When using the pull back, that needs to be the first segment of the turn movement. Pull back, way back, the tips will be ready to engage the snow, and then make the turn movement you use.

*I've skied with a fellow who's ankles don't bend. They just don't. In order to get him out of the back seat an alignment specialist set him up with raised heel bindings, heel pads, and altered shaft angle. He's a special case, but there are adjustments and alterations to get almost anyone balanced.

**I put Tyrolia Attack13 demo bindings on a pair of skis. I had to work to get out of the back seat on those. A 1/8" plexiglass shim under the heel bindings centered me. That's me. You're you. Something else entirely may be needed to get you balanced.

 

[dj61]

"If I have a boot that is gas pedaled, hence already putting me into a more dorsiflexed position, does that create a less-desirable platform for active dorsiflexion?"

Amy, the supposition is wrong. The goal is to get the body's center of mass over the sweet spot on the skis, somewhere forward of the toe binding. It is not about ankle bend angle,* nor pressure against the boot tongue nor pressure on the toes or ball of the foot. You may need changes to the boot shaft angle--tilt the cuff forward-- or changes to the binding delta angle--shim under the heel binding**--or a spoiler between the cuff and the back of the liner. A small number of people benefit from a heel pad. Some people need to do adjustments in the opposite direction--we're each an individual. You really need a visit to a good boot alignment person. Not all good boot fitters are also good at alignment.

Dorsiflexion works for skiers who are close to being properly balanced and can pull themselves the small amount needed to get where they want to be. The tibialis anterior muscles are relatively small and weak. They can do a little. Pulling the skis back under the skier uses the big strong hamstring muscles and is much more effective. The shin pressure against the cuff is your gauge to know where you are. When a certain pressure there happens and you ski great, you know to return to that pressure. Pull the skis back until the body center of mass is over the skis sweet spot, feel the shin pressure you know works for you, and you'll ski great. When using the pull back, that needs to be the first segment of the turn movement. Pull back, way back, the tips will be ready to engage the snow, and then make the turn movement you use.

*I've skied with a fellow who's ankles don't bend. They just don't. In order to get him out of the back seat an alignment specialist set him up with raised heel bindings, heel pads, and altered shaft angle. He's a special case, but there are adjustments and alterations to get almost anyone balanced.

**I put Tyrolia Attack13 demo bindings on a pair of skis. I had to work to get out of the back seat on those. A 1/8" plexiglass shim under the heel bindings centered me. That's me. You're you. Something else entirely may be needed to get you balanced.

Thank you, Henri. You hit the nail on its head. Dorsiflexion should be part of an integral motion pattern resulting in pull back involving many muscle groups in particular hamstrings and glutes. It is not an isolated movement.

 

[markojp]

We do one thing singularly to build awareness, then blend it back into the whole. I don't know that anyone's arguing that one ONLY dorsiflects.