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# Inside ski pressure ? weight on inside ski - Page 4

Luckily, I'm not in a lesson now. In teaching, I may share this information, depending on the student.

Based on a given pressure and surface (be it ice or soft snow) a single ski will require a specific (edge) angle to eliminate slip or skidding. If the same the same pressure were evenly distributed over two skis, the edge angle could be reduced or the pressure increased to achieve the same lack of skid. Cumulative pressure does not change with two skis vs. one, distribution does. Increased drag (ie. better hold) is a result of increased surface.

The CM, in turns, should lie along the line of the tilt angle of apparent gravity over the engaged edge(s). Your CM should push your edges into the earth along this line. If you are distributing your pressure along two skis, the width of the line of the angle is wider. Balance is lost when moving too far off this line. A wider line results in a larger margin for error (ie. better balance).

With regard to the original post. If the above are true, the LII skier seems well within the bounds of efficient skiing by wanting to use the inside ski. How much and when the pressure distribution is altered is of paramount consideration. If the inside ski is supporting the majority of CM through the shaping phase and belly of the turn, better results may be achieved by reducing that support.
Interesting discussion.

I'm going from old school to new so please set me straight.

A typical old school drill when learning to parallel was to lift the uphill ski (except for the shovel) while in a traverse, unweight the downhill ski and transfer the weight to what is to become the new downhill (outside) ski as you slide through the turn at the same time raising the new uphill (inside) ski. This was an exaggerated exersize to insure that the weight was always on the downhill (outside) ski so you wouldn't catch an edge while sliding.

I was under the impression that part of the new school techniques entailed widening the stance and putting both skis to work rather than letting the outside ski carry all the force of the carved turn. Since you're not skidding you shouldn't catch the inside edge of the inside ski.

I've been working on doing this at moderate speeds, it happens naturally if you go so fast that it's not physical possible to carry the G loads on one leg, fine if you're running gates but too fast for safe free skiing and you'ld burn out before 11:00am anyway.

When the weight is on the outside ski the other leg will naturally drift inwards and you find yourself skiing with your legs together... not cool any more.

So am I barking up the wrong tree by trying to carve both skis at the same time or is carving only on the outside ski what's considered correct?

Thanks,
Steve
Both skis can "carve". The inside ski will travel a shorter distance than the outside ski. The pressure that builds as a result of turn forces can be used on the outside ski allowing it to bend and carve (more than the inside ski) allowing it to travel the larger arc in the same time frame. Accurate distribution of the available pressure should result in uniform skid (travel along the tangent) through the turn on both edges.
Be advised, "carving" both skis may not be correct. The desired vs. actual outcome from your movements may be perceived as governing correctness. If your turns keep you on the hill (year after year), you are already correct; you are having fun. There may however, be movement patterns that allow to have even more fun. Fun, I believe is why most of us ski and should govern the application of the terms "correct" and "right" within my profession (snowsports education). This is where epic may help the LII skier find a better way down the hill. The LII skier may be in a catch-22 trying to ski whats "right". He/she may realize further benefits by reviewing the facts, and their source, that lead to the present interpretation of the "right" way of using the inside ski.
Quote:
 Originally Posted by Procreator Interesting discussion. I was under the impression that part of the new school techniques entailed widening the stance and putting both skis to work rather than letting the outside ski carry all the force of the carved turn. Since you're not skidding you shouldn't catch the inside edge of the inside ski. When the weight is on the outside ski the other leg will naturally drift inwards and you find yourself skiing with your legs together... not cool any more. So am I barking up the wrong tree by trying to carve both skis at the same time or is carving only on the outside ski what's considered correct? Thanks, Steve

Steve, great question, and I wonder how Lito (Breakthrough on Skis) would answer that!
mrzinwin - Personally, I do have the problem of putting excessive weight on my inside ski during the beginning of the turn. I find that sometimes, as I reach the fall line, my outside ski will dart away from me, while my inside ski will continue in a tight-radius carve. So if someone would simply tell me to keep most of the weight on the outside ski while flexing my inside leg (if I am making a left turn, it feels like the inside edge of the left ski is "scraping" the medial aspect of my right heel/leg), then that would be a lot more helpful than arguing over the physics definitions of "weight" and "pressure."
__________________________________________________ _____________

Think inside ski the brain, outside the brawn.

Point the inside knee down the hill and make that leg short and the outside leg has more power. How much more power (weight, say) depends on conditions. Ice: 90% more. Pow: 60% more.
Bryan, If I may ask, you say you're a snowsports educator. What does that mean? Your bio is pretty empty, care to share a little more?
Quote:
 Both skis can "carve". The inside ski will travel a shorter distance than the outside ski. The pressure that builds as a result of turn forces can be used on the outside ski allowing it to bend and carve (more than the inside ski) allowing it to travel the larger arc in the same time frame. Accurate distribution of the available pressure should result in uniform skid (travel along the tangent) through the turn on both edges.
Thanks Bryan, I've noticed this tendency for the inside ski to scissors (herringbone) into the turn if it gets loaded too much, now I know why. Fskier is experiencing the same thing really, but since his tendency is load the inside ski the sensation is that it's the outside ski that is getting off track.

I've found that by staggering, inside ski significantly forward, the tendency is reduced. Probably because the staggering gives the illusion that my feet are not close together but in reality they are and therefore the distance traveled by both skis is so similar that there is little difference in the turn radius.

Of course, as you say, the best is to just go have fun but in my case I enjoy investing some time (without getting obsessed) in trying to optimize technique, for me it adds more challenge and hopefully some rewards to the game.

Steve
Pro-C, it was actually mrzinwin that seemed to be having a problem with that inside ski hooking up and the outside wandering away.

I ditched that problem by concentrating on making that inside leg short...well ...and also mostly because I am an old-schooler trying to reform and that inside leg didn't exist back then.

On the inside ski-lead thing, I try to concentrate on sucking that ski back in by keeping pressure on the front cuff...something that, if you also tele, is familiar. This I find keeps my legs under me and also helps me avoid building excessive counter too early - which is also a holdover from the old school.

It is frustrating in a way as, in my case with many others, it's teaching an old dog new trix. I'm getting it. The (not so) old Schmidt-style I thought to be great is slowly giving way.

I go for my L3 in 2 weeks at Sugarloaf, ME.
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 Pro-C, it was actually mrzinwin that seemed to be having a problem with that inside ski hooking up and the outside wandering away.

Oops! So true, sorry friend!
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 Originally Posted by fskier I go for my L3 in 2 weeks at Sugarloaf, ME.
Good luck
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 Originally Posted by rogue skier I will try not to ramble... To feel that pressure your inside ski needs to be controlled and under your center. Too far ahead and you lose shin contact hence pressure. Too far back and you get too much.
Back to the original question, which is a really good question:

"Well, IMHO pressuring the ski and weighting the ski are not actually the same thing. Maybe it has to do with vectors of where the force goes? I can see how pressure and weighting could be viewed as the same thing, but in practice, I don't think they really are the same."

Weighting the ski vs. pressuring the ski: have you ever done really fast high g turns and tried hard to keep the turn tight ie back up the hill. I watched Bode demonstrate that skill and he really drives his knee forward to perssure the ski. Rogue talks about cm under the skier, more pressure means move the ski back. I know that I drive my knee while pressuring the boot to keep control of the turn and continue the turn. I think that's pressure.

It's something I picked up from watching a video of Bode. I really don't know much about MA and these discussions, but this to me is weighting the ski then pressuring the ski.

Does anyone remember "Edge, pressure, steer." What did they mean by pressure?
Quote:
 Originally Posted by Paul Jones Is this true? I can understand two skis provide a wider base for balance. But do two skis hold better than one, as in one - the outside ski during a turn.
That is not an easy question to answer. Common sense says that if we distribute weight over 2 skis, we will get better edge hold as the amount of forces acting on the snow per unit area will be reduced.

On the other hand someone else might argue that if we distribute weight over 2 skis, we will get less edge grip becuase each ski will now have less weight on it to bite the snow, thereby reducing the total contact/support area. That was not our original intent.

A good experiment might be to get a snowboarder and a skier ( both excellent in their disciplines and of equal mass including equipment ), give them both planks with 15m sidecuts and have them carve a turn through accordingly placed gates starting with a medium velocity. Velocity at turn entry would be increased incrementally until someone skids somewhere along the turn. Obviously the skier should be instructed to use 50/50 distribution so we can settle the 1 edge vs. 2 edges debate along with the skiing vs. boarding debate as a bonus
This thread has sort of come full circle. My only question has to do with how you pressure a ski. Yes pressure and weight are different things but can you pressure a ski that has no weight on it? Notice that I'm not talking about changing fore/aft positioning to redistribute (concentrate) pressure on a specific part of the ski. I like how PJ described this as weight the ski then pressure it.
The only thing we all agree on is that we'll never agree on what weighting and pressuring mean outside of engineering parlance.

How do you pressure a ski?...by lightening the other one. Is that something we can agree on?

Can you pressure a ski that has no weight on it?...what do pressure and weight mean?

fskier...with your bad knees, try not pointing your knees to the side at all. Keep the knees straight ahead and tip from the inside ankle. It'll work great. Allow the inside knee and the hips to go toward the hill, but don't point or drive them.

Cirquerider...drilling on one ski or one ski heavy inside or outside is great to be able to handle whatever situation that last bump threw us into. As far as 80%/20% weight distribution, how exactly does one measure that? It can't be done. Sure, the European universities that do research on skiing and the ski manufacturers can put strain gauges and other instrumentation on the skis, but for you and me, how do we gauge the weight distribution?

Procreator...wide stance and two-footed balance is old new-school. So is great tip lead of the inside ski. A walking-width stance, light inside ski, and minimal tip lead works great. The recreational version of the fundamentals shown here allow for bigger tipping angles of the legs to the snow, more weight on the outside ski to curve it more, and the inside ski under the body for better fore & aft weight distribution and more ability to put that ski on its edge. The DCLs running clinics have an inch or two of space showing between their ankles this year.
Maybe weight distribution along the ski is part of the word pressure as it relates to skiing. Bending the ski is one aspect of skiing that we don't talk about much. But the decision to bend the ski more, relies on pressure, someones weight compounded by g-force. How is it that my 16m TF can carve at say 9m by using direction change and uneven terrain to bend the ski.

Pressure the ski for me also means using a more forward part of the sweet spot so that you are not skiing the tails when g-forces are high. How do you pressure a more forward part of the ski without moving your cm too far forward?

One of the most exciting aspects of skiing is bending the ski, especially on the new equipment. I don't know anything about the physics of the topic, but controlling the amount of bend in the ski is about more than weighting the ski, I think
Quote:
 Procreator...wide stance and two-footed balance is old new-school. So is great tip lead of the inside ski. A walking-width stance, light inside ski, and minimal tip lead works great. The recreational version of the fundamentals shown here allow for bigger tipping angles of the legs to the snow, more weight on the outside ski to curve it more, and the inside ski under the body for better fore & aft weight distribution and more ability to put that ski on its edge. The DCLs running clinics have an inch or two of space showing between their ankles this year.
Thanks SoftSnowGuy, you've made my day! This is what I do naturally... when I'm not trying to force myself to load the inside ski. Admittedly the walking-width stance has, and still does sometimes, require some conscience effort. I skiied with my legs glued together for so many years it's become second nature.

Notice how I've skillfully weaseled out of using those polemic terms "weighting" and "pressuring" by employing "load"!!

Steve
This little analysis I accidently found shows an interesting observation about over-weighting the uphill ski at certain points in the turn... It definitely helped some folks (like me) figure out their imbalance issues at times.

The "experiment" that Red Runs asks for has been done in a more controlled way then using people.
George Twardokens, father of Eva, Professor of Kineseology at U of Nevada, Reno, former PSIA-W examiner did an experiment several years ago using fixtures, measuring devices, and small skis. His findings were published in the Pro skier.
As I remember it (I've slept since reading it so I could be wrong) the Prof. found that total edge penetration into a hard surface (ice) was greater when 2 skis were weighted as opposed to 1 ski with the same total weight. While 1 ski did penetrate farther then either of the 2, when the 2 were added together their total penetration was greater(think penetration X 2 X length of edge)
I think he also addressed the issue of would 1 ski penetrating farther "hold" better then 2 with each penetrating less. I'm fairly sure he found that 2 skis distributing pressure over a larger surface (edge length X 2= less pressure per square inch) was the better option as it is less likely to cause the surface being penetrated to give way from to much pressure.
Does this test out come transfer to real skiing. There have been quite a few who don't agree.
SSG,
Pressuring a ski implies it is in contact with the snow. We are not limited to lifting one ski and allowing the remaining ski to bear all of our weight thus increasing the psi of pressure on the ski still in contact with the snow. . You can also extend a leg and increase pressure on that ski. So IMO no would be the answer to the question about how do you pressure a ski.
Here's an idea...
Barometric pressure and the fit of the boot can cause pressure on the foot independent of any weight bearing. Beyond that if the foot is in contact with the snow and the edge is engaged, there is some weight bearing going on. It is this weight bearing that causes the pressure in the first place. Can we change that by up or down "unweighting" movements? Absolutely! The concept of doing this to facilitate an edge change goes way back. It should be pointed out though that in reality it is changing the amount of pressure at the ski/snow interface.
Adding momentum to the gravitational pull adds pressure to the ski but how do we express that without adding an additional term or risking more confusion? You don't.
Can you pressure a ski without any weight on the ski? Can you add pressure without adding more weight? IMO it takes a little of your weight to cause the pressure we are using to engage the edge. So no would be my answer. You can change where it is focussed by levering but I wonder if your total pressure increases when we relocate the foot or CoM. If it does how do you accomplish this without changing the percentage of weight bearing that foot is doing?
Paul,
Does it test out? It has for me in my skiing.
My point in sharing the info is that we have an issue of perception vs testable, repeatable, measurable results being discussed here.
Actually skiing? I can ski on 1 foot. I can ski on 2 feet. I can ski with both feet on the snow but concentrate on putting all my weight on either inside or outside foot.
When skiing powder, 1 footed skiing doesn't work for me. I ski mostly in Michigan where hard pack/ice are forgiving of outside foot dominance. When I go out west I have to make adjustments because deep powder is not so forgiving and I'll admit its a struggle to make the needed adjsutments. If I ski more balanced in MI it works, and has the bonus of if 1 edge loses grip the other is already engaged and a very small adjustment allows me to stay fairly well balanced and the adjustments needed when I get out west are not so big a deal.

Twardokens' article is the only objective analysis I've ever seen. If someone knows of other actual testing that's been done I'm open to seeing it. The rest, including mine, is just perception and subject to a whole lot of misperception.

That said, I'm off to play on the snow for 10 days. I wish I could say in the snow but I'm stuck in MI.
All this hypothetical techno-babble is great, and I do not disagree with some of the conclusions drawn. The pure physics and resultant effects of contemporary equipment is quite accurate. Until you re-insert the human body!

I'm sorry, but where did we lose sight of the physical limitations of the human body? Does anybody out there remember anatomy?

There are certain things the body can do, and certain things it can not. When creating the movements necessary to edge one or both skis, these basic limitations must be observed. There are movements the body can perform which engage a great many muscles or muscle groups, while there are others which engage very few.

As the OP is focused on the amounts or degree of weight/pressure being applied to the inside ski as compared to the outside ski, I will keep my comments focused there as well.

Let's begin with the outside ski. The movement made to tip the ski to its inside edge (BTE) is an ADDUCTIVE movement. To create this movement, there are many muscles and muscle groups which are activated and involved. This is the same for any rotational activity of the leg as well. The number/ amount of muscles involved in a medial movement is significant. Both of these movements engage some of the largest/strongest muscles in the body.

But on the other hand, tipping the inside ski to it's outside edge (LTE) is an ABDUCTIVE movement. There are less than half the muscles available to create this movement, as compared to the ADDUCTIVE side. Again, this is also true with any turning of the ski in a lateral direction.

Less muscle = less strength. Simple premise! So to believe that you can be an effective skier and have equal weight/pressure on both skis implies that you do not truly understand the previously described limitations.

When you take this concept to the next dimension and add the stress of actually skiing down a hill, then some of the available musculature is drawn off in order to support the management of various pressures and turning movements, as well as the need to tip the ski to its edge.

The degree to which a turn is completed across the fall line also plays a major role in determining the role the inside ski will play, and how much weight/pressure it should be carrying. But that is for another postâ€¦.

### Inside/Outside ski pressure

Sometimes it's more fun not to have any pressure on either ski

Quote:
 Originally Posted by vail snopro The degree to which a turn is completed across the fall line also plays a major role in determining the role the inside ski will play, and how much weight/pressure it should be carrying. But that is for another postâ€¦.
To simplify, you are suggesting that weight and pressure are the same.

And the rest of the post was helpful too.
Inside ski pressure? As demonstrated by the current leader of the GS World Cup standings for 2008:

No one is suggesting weight and pressure are the same thing. Just that without some weight on a ski how would you pressure it.
No- weight and pressure are NOT the same thing.

In my own head, I quite clearly differentiate between weight and pressure.

Weight is static

Pressure is dynamic

In my previous post I .../... both words so that readers would not get caught up by which word was used, rather than understand the meaning of the post. Since many seem to believe these two words are interchangeable, decided not to enter that arguement at this time.
Quote:
 Originally Posted by justanotherskipro No one is suggesting weight and pressure are the same thing. Just that without some weight on a ski how would you pressure it.
That's a good point, but what does it mean "to pressure"? It does mean moving your weight to the ski, but it seems to me like it means more. But I really don't know.

The idea of bending the ski and flexing the boot - changing the radius - things like that are not the same as putting your weight on the down hill ski. Even the "gas peddal" motion in bumps is a form of pressuring the front of the ski.

Also, (picture above) look at the knee position on the inside ski. She may have weight on that ski, but that's an example of pressure.
Do this experiment. Take a chair and stand next to it so that one foot is flexed placed on it (inside leg) and the other extended next to it (outside leg) on the floor. If you have all your weight on your outside leg you can stand there all day but if you try to shift all your weight on the inside leg bent up 90 deg you can only do a couple of seconds. And you will have to adjust your balance pritty much too from your original stance. Now do it with slalom boots on and you will see that its allmost impossible since your inside foot on the chair gets placed very far forward. Put skis on if you like to gain better for aft balance but one thing is clear, shifting weight to that inside ski seriously messes with your balance and causes a lot of muscle strain. Take two scales and see how much weight you can comfortably place on your inside ski without getting in the back seat and without placing too much strain on your inside leg muscles and knee ligaments.

Weight is mass times gravity.
Pressure is force per square area.

Remember that your boot/ski/binding combo carries weight. If you in the middle of a turn lift your inside ski up off the snow that movement will cause more pressure on the outside ski. All extention movements will do the same. To get the most pressure per square area you should as you turn as tightly as possible at high speed in order to create a lot of centripetal force extend your outside leg to cause your CoM to move upward and retract your inside leg at the same time. All this at the moment you are in the low C-part of the turn in order to get the extention movements to work in opposite direction of gravity.
Absolutely Paul! The point I am making is the original OP was talking about leaving some weight on the inside ski. Which is halfway to understanding how to add pressure to that ski. Some of your weight needs to remain on the ski. How much depends on the tactic. Those that argue that pulling the leg back adds pressure but no weight are also only looking at half the picture. Increasing the pressure also shifts more weight to that ski because you are talking about supporting the body on two supports, not one. Changing how much weight/pressure one support carries immediately changes how much weight/pressure the other carries. Even if it is only the weight of the supporting structure there is still weight on that contact point. The tell tale sign being the fact that the ski leaves a track in the snow.
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