RAMPING UP THE POWER OF YOUR STANCE


Note to the reader

The post that follows was originally published on March 1, 2016. At the time that I wrote it, I was trying to identify the optimal net (total) ramp angle or NRA using fixed angle ramps. But I found the process to be inconclusive for reasons I give in my recent posts on the dynamic ramp assessment device. I am reposting this older post because many of the concepts expressed are even more relevant in view of the results seen with the dynamic ramp assessment device and boot boards altered to the same ramp angle identified in dynamic testing.


RAMPING UP THE POWER OF YOUR STANCE

The foundation of a strong technique is a strong stance. But what makes a strong stance? The angle of the combined ramps of the binding and boot board or zeppa in relation to the base of the ski. If the net ramp angle weren’t important, binding and boot makers would make their products with no ramp. If ramp angle doesn’t make a difference, why bother? But not only does net ramp angle make a difference, it has a significant effect on stance.  Stance affects balance and muscle power, especially the ability of eccentric gastrocnemius-soleus complex muscle contraction to absorb shocks that would otherwise be transmitted up the leg to the knees and back. I discussed some of these issues in WHAT’S YOUR ANGLE? – : https://skimoves.me/2014/03/29/ski-boots-whats-your-angle/ ‎

If there were a problem, and there is, the ski industry is all over the place especially when in comes to binding ramp. There doesn’t appear to be any industry standards and especially any continuity between products. Worse, most skiers assume that their ski boots are putting them in the optimal stance. Without a reference they have no way of knowing. The Stance Ramp can give them that reference especially when it comes to how much ramp is enough, how much ramp is too much and how much ramp is too little.

Note Added March 19, 2018 – Having a kinesthetic sense of a stance based on tensegrity gives a skier a valuable tool that when used in a structured process can help them assess the effect of zeppa-delta ramp angle and the constraint imposed on their feet and legs by the structures of a ski boot.

In 1978, when I was building boots for female racers with small feet, I noticed that they were skiing like they were wearing high heel shoes. When I started checking their bindings and boot board ramps, I found out why. Some had 10 or 12 degrees or more of net ramp angle. After I started doing stance training with racers on a ramped board I discovered through empirical experiments that about 3 degrees of ramp angle seemed to give skiers the strongest stance.

Note Added March 19, 2018 – It now appears as if 3 degrees is the upper limit of the zone of stability. This explains why skiers started to ski better when the net ramp angle approached 3 degrees.

I didn’t really understand why until much later. Was the process scientific? No, not at all. Do studies of this critical issue need to be done? Absolutely. If I figured out that ramp angle was a critical issue almost 40 years ago, why is it that no studies appear to have done in the intervening years to determine the affects of ramp angle and identity the optimal angle?

With input from skiers in different parts of the world over the past two years, I have narrowed the ideal ramp angle down to about 2.7 degrees. This seems to be something of a standard in World Cup. Through experiments over the past few months, I have found that changes of 0.1 degrees can make a significant and easily perceivable difference. Optimal ramp angle isn’t just critical for World Cup racers, it is critical for all skiers. The easiest way to convince yourself of the importance of optimal ramp angle is for you to experience the effects of ramp angle through experimentation. How? With a Stance Ramp set to a base reference angle of 2.5 degrees.

The Stance Ramp lets skiers stand in their ski stance (barefoot is best) on a flat, level, surface then assume the same stance on the Stance Ramp, compare the kinaesthetic sense and judge whether they feel stronger of weaker. The angle of the Stance Ramp can be predictably increased or decreased by inserting shims at either end between the ramp and the surface it is supported on. When the ramp angle that makes the stance feel the strongest is arrived at, it can compared to the ramp angle of the ski boot board by having one foot on the Stance Ramp and the other in the ski boot.

The best part? The Stance Ramp is easy and inexpensive to make with readily available materials. I made mine out of some scraps of plywood I had lying around. Here’s what the Stance Ramp I made looks like. You stand with one foot on either side of the stiffener in the center with your heels at the high end (left end in the photo below).

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Here’s a top (plan) view. It is a good idea to check the surface the ramp will sit on to make sure it is very close to level.

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Here’s the underside of the Stance Ramp showing the element at the rear that gives the ramp its 2.5 degree angle. The stiffener in the center is important to ensure the ramp doesn’t flex under your weight.

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The sketch below is a basic plan for a Stance Ramp. The only critical details are the height or thickness of the element that lifts the rear aspect of the ramp to achieve and 2.5 degree angle (angle A) and the distance the lift element is placed from the front edge of the ramp. The stiffening element in the center of my ramp is 8 cm wide. The ramp has to be big enough to stand with the feet under the hips and long enough to accommodate the length of the feet.

Stance Ramp

An online right angle calculator such as the one at cleavebooks.co.uk can be used to calculate the spacing of the lift element from the low end (front edge) of the ramp based on its thickness.

SR calculate

Once the optimal ramp angle is arrived at, the Stance Ramp can be used in combination with the ski boot shell to confirm that the boot board is at the same angle.

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In my next post, I will discuss what I call the Resistive Shank Angle that is the base to build  a strong stance on.

14 comments

  1. Seems we are back to the same argument going on ever since high back boots came out. Everyone has different biomechanics and ramp angle is very personal.
    Also many different sports people have gotten used to shoe ramp angle but that doesn’t mean they wouldn’t do well with zero ramp as we evolved with for several million years.
    Just a thought.

    1. You are engaging in sophistry and tobacco industry tactics. But I’ll humour you for a second.

      Assuming you are correct, which you are not, the ski industry would appear to have an enormous liability problem because the odds are overwhelming that ramp angle is wrong for the majority of skiers. Worse, when boot ramp is combined with binding ramp (which is all over the place), the resulting net ramp becomes worse than Las Vegas odds.

      Nice one.

      1. So don’t personalise each person’s ramp?
        Glad to have found your blog. Many interesting ideas!
        Still worry about paralysis through analysis

      2. “So don’t personalise each person’s ramp?”
        That’s not what I said. I said that 2.5 degrees is a start point and that shims can added to increase or decrease ramp angle. In the ramp in my post 2 mm = 0.1 degree. Can skiers sense this small amount? I can tell you that I had a racer I had a working add 1.5 mm shims to either the heel or forefoot between runs after warming up and not only did they sense when it was wrong, I could clearly see the effects in the video. The real test is to increase ramp in what you think is the wrong direction. If it has a negative effect, you know the existing ramp needs to be reduced.

        Ramp angle has a huge impact on skier performance. Analysis by paralysis is a termed coined by ski pros who don’t know and and aren’t motivated to know the underlying science. Telling a skier to do something when they can’t because their stance is weak because of their boots is the height of stupidity. Fixing the problem so one doesn’t have tell them anything requires comprehensive knowledge and analytical skills. Labelling this paralysis through analysis as many do is an tacit admission of “too lazy and don’t give a crap’.

        I will try and give a simple implication of why ramp angle is important in a post soon. For now, it relates to muscle power, balance and the ability of the defences to protect the lower limb.

      3. This is standard flak in many forums intended to obfuscate and distract away from the real issues. I haven’t gotten to offering an explanation for why shank angle is important and especially why it should similar in most people. Is it exactly the same for everyone? I don’t know. As far as I know, no one has done the studies. Is shank angle important? Absolutely. That is why studies need to be done. But studies need to be done by those who are putting ramp in their products with absolutely no consistency or continuity. If one is designing and selling a product, they should know how and why it affects the user.

  2. After one of the recent WC races,Hirscher,who is known as a stickler when it comes to equipment made the cryptic remark that he changed his “Schwerpunkt” (German for COM) between the first and second run. He went further into detail by saying he took a big risk by turning ” so many screws”BTW on the new Atomic boots you can adjust the boot board angle.

    1. Yes, and since the radius of every turn is different, he stops and changes skis at every gate and uses a different boot for every every run of every race. I have also heard that he never walks the same. Sometimes, he walks backwards, sometimes he walks in circles, sometimes he z-zags, sometimes he walks on his hands. Sometimes, he even bounces on his head. And you what, it is all the same. Everyone in the world is different. No one walks the same. But there is absolutely no difference. One way of walking is equally as good as another.

      Stance in skiing is the same. Everyone is different. Some ski with their ankles straight. Some ski with their knees touching their ski tips. All stances are equally good. That is the great thing about skiing. Every and any technique is personal. All stances and technique are equally good.

      1. Of course ramp is important. The old concept that heel lifts are the greatest thing that ever happened to female skiers is crazy making. The true problem with this and a huge number of blanket statements about ski equipment is that it’s not evidence based. I applaud you if you are willing to look for evidence to back up any of your multiple ideas.

      2. “The true problem with this and a huge number of blanket statements about ski equipment is that it’s not evidence based. I applaud you if you are willing to look for evidence to back up any of your multiple ideas.”

        I am with you every step of the way on this one.

        The big problem in skiing is that people just seem to make up stuff without even offering a theory on how it works or without even offering a plausible explanation. Worse, people seem to buy into questionable premises. The heel lift gimmick was one. It made no sense. Elevating the heel, reduces dorsiflexion and substantially reduces EC contractile force.

        When I was asked by Steve Podborski in 1983 to try and design a new ski boot I was unwilling to go forward in 1991 until we engaged scientists to conduct studies to validate my hypothetical model. Yes, it was based on applied science because that is the classic approach. But a theory is exactly that until proven in vivo which it was. The conclusions also need to meet the test of being reproducible.

        One of the issues our studies looked at was the effect of shank angle on muscle power. We didn’t have the funds or technology to perform the kinds of studies that can be done today. But we got enough data to show that preventing the shin from acquiring the optimal shank angle greatly reduced eccentric muscle power of the triceps surae complex. Evidence is now emerging from studies done in other fields that can be extrapolated to skiing. But studies need to be done and the industry needs to perform them or at least fund them. Until this happens, subjective studies are the only option. I will qualify this by stating that it has been my experience that no matter how much glowing lab results one has, if an elite athlete says it doesn’t work for them then it doesn’t work, PERIOD.

  3. What are your thoughts on mogul skiers that put in (sometime quite large) heel lifts to allow them to keep a straighter back while absorbing the bumps? Same effect as a weightlifting shoe in a squat…

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