RAMP ANGLE RESONATES


My recent series of posts on the effect of ramp angle on stance seems to have piqued interest in this subject. The two posts with most views in recent weeks are:

  • #1 – RAMPING UP THE POWER OF YOUR STANCE and
  • #2 – STANCE BASICS 101; RESISTIVE SHANK ANGLE

The following postS were close behind,

  • STANCE BASICS 101: ECCENTRIC MUSCLE POWER
  • STANCE BASICS 101; RAMP ANGLE TIPPING POINT
  • SKI BOOTS: WHAT’S YOUR ANGLE
  • CALCULATING RAMP ANGLE
  • THE SHOCKING TRUTH ABOUT POWER STRAPS

Since I first raised the issue of net or compound ramp angle on June 2, 2013 in my post , Ski Racing: An Unlevel Playing Field, I started to look critically at ramp angle, especially the net or compound ramp angle. This includes the contribution of ramp angle from boot boards and bindings. In past year, in working closely with skiers in other parts of the world, including a racer in Europe who I work with on an almost daily basis where the effect of every change is carefully evaluated  and documented on video, I have tentatively concluded that ramp angle may be the single most important factor affecting skier balance and control of the skis.

In my post,  SKI RACING: AN UNLEVEL PLAYING FIELD, I said of my work back in 1977,

“But I was adjusting two other things that no one even seemed to even be aware were issues; net ramp angle and position of the ball of the foot and big toe in relation to the ski edge underfoot.”

I went on the explain,

“Net ramp angle is the inclination of the sole of the foot in relation to the surface of the snow. It affects the muscles a racer can use and especially the ability to apply force to the fore body of a ski and the ability to activate what I call the auto processes of edge control and turning forces. Two factors contribute to forward inclination; 1) the ramp angle of the boot board that the sole of the foot is supported on and , 2) the angle created by the heel and toe plates of the ski binding. I don’t know where they are today, but back in 1977 ramp angles were all over the map in both boot and binding brands and even models. Because of this, both the base angle of the boot sole plate and binding had to be considered as a unit in determining net ramp angle. Although few if any were aware of this issue, to me it explained why a racer’s skiing and results sometimes went downhill when they changed to a different ski binding or boot or worse, changed both.”

Ramp Angle Roulette

If I thought that ramp angle was all over the map back in 1977, the situation is infinitely worse today. Back in 1977, there were a limited number of bindings on the market. Today it seems as if the sky is the limit.

A few weeks ago, a recreational skier who was having problems with their boots and skiing asked me for my assistance. It quickly became obvious that the boots, which had no modification, were far too tight and especially too narrow for the skier’s wide peasant feet and squared off toes. When I checked ramp angles, the boot board was 3.27 degrees and not monoplanar (not flat). The ramp of the bindings was 1.90 degrees as set for the length of the boots. The net ramp angle was 5.17 degrees.

Adjusting the ramp angle of the boot board was not possible because it was an injected plastic form that is not easily modified. Since new boots were needed, I made sure that the ramp angle of the boot board could be modified. Bindings were another matter entirely. When I started what became an extensive and exhaustive search for a recreational binding with zero ramp, I could find none. Worse, when I started to check bindings for height differences in the toe and heel piece platforms, I could find no consistency, let alone even a hint of any sign of any standard. They all seemed to be different. Since modifying bindings is not an option, at this point I am at an impasse with no solution to offer the skier.

The KIS Principle 

The goto mantra of the ski industry is the KIS principle; Keep It Simple. I fully subscribe to this principle which is why my efforts are directed at creating an environment in the ski equipment system, especially in the ski boot, that supports optimal human performance and balance. From a perspective of balance, skiing is one of the most complex activities we engage in. The ski amounts to perturbation platform in motion over undulating terrain with different coefficients of friction in a dynamic, constantly changing 3-dimensional physical environment. The wide variances between ramp angles in ski boots and bindings and the fact that the ramp angle contribution from bindings is variable according to the boot sole length, make the combination of net ramp angles both unpredictable and almost unlimited. When I  noted back in 1977 that the lack of any apparent standards, “explained why a racer’s skiing and results sometimes went downhill when they changed to a different ski binding or boot or worse, changed both”, the situation is far worse today. How many careers of promising racer’s have been compromised because the effect of ramp angle was not appreciated?

The Question

There are two possibilities.

  1. Ramp angle has no significant effect on skier function, especially balance, in which case the standard should be zero boot board and binding ramp, or
  2. Ramp angle has a profound effect on skier function, especially balance, in which case studies should be done to ascertain the effects of ramp angle and especially a method by which to determine individual ramp angles for optimal function and balance.

If it turns out that ramp angle is as critical as my recent experiences and subjective experiments are suggesting, then the current state of the unlimited possible ramp variances skiers are presented with is the antithesis of the KIS principle when it comes to making skiing easy and enjoyable.

This brings us to the question, is ramp angle critical or irrelevant?

  • If ramp angle is irrelevant, why is it present in boots and bindings?
  • If ramp angle is critical, how can it be variable with no consistency in application?

In my next post, Michael who has been applying material from my blog will relate his experiences in his own words.

 

 

 

 

11 comments

  1. I was thinking of getting a pair of GS skis and checked the Rossi web site. The binding for the skis recommended includes the following in the “detail” (reduced ramp angles for a more neutral, upright stance) Have they been reading your blog??? Please keep writing it sometimes is hard to follow but generally I get the idea. Would be nice if there was someplace that could do all that you talk about???
    Thanks!

    1. I have quite a few followers associated with equipment makers. I thought about writing a book years ago. But a book is static. I believe that one should never stop learning. So I prefer a format like a blog. I believe footwear is on the verge of being dragged screaming and kicking out of the dark ages and into this century as technologies like 3-D printing and CARV evolve and studies continue to show that much of what has been and continues to be presented as technology is really just marketing with zero science behind it.

  2. Hi David,

    I’ve been enjoying these posts on net ramp angle. Based on what I’ve read and previous response to some comments it would seem that exploring ramp angle with toe/heel binding height is a good place to start? However, you’re comment on zeroing bindings and its affect on boot shaft angle makes me think one needs to go about this one small adjustment at a time.

    Thanks,

    1. Hi Jay, my experiences in trying to pin down the optimal ramp angle over the past year in working with skiers in other parts of the world by email and in person, served as the impetus for the design of the Roll Over trainer (which I am now revising) and, more recently, the Stance Ramp which is now in generation three. What I have found is that a strong ski stance is unnatural. It must be taught. Further, I have found that a strong stance cannot be rehearsed on a flat surface. While, the optimal ramp angle appears to be in the order of 2.5 to 2.7 degrees, I have identified several factors that could affect it. So at present there is no basis to assume that ramp angle is one size fits all.

      The problem with starting with an arbitrary angle of 2.5 degrees with a device like the Stance Ramp is that it suggests to someone testing it that the angle is normal. They can try to make it feel right when it isn’t. The 3rd generation Stance Ramp, which I will post on soon, is blind in that the subject adjusts the angle until it feels best for them after which I measure it and calculate the angle. This seems to be the best place to start.

      Suppose that I felt strongest at an angle of 2.45 degrees on the Stance Ramp. I would lock the angle and rehearse my stance on it to acquire a kinaesthetic sense of a strong stance. Then if the ramp angle of my boot board were 3.1 degrees, I would slowly reduce it in increments alternating between my left and right boot boards until I either found the best angle or arrived at 2.45 degrees. Once I am close, I add 1 mm shims under the heel and then under the forefoot to confirm the angle. If I make the angle worse, I sense it right away.

      When ramp angle is right, I check forward lean, shaft tension etc to make sure I am able to assume the Resistive Shank Angle. At that point I just ski. I do not make any further changes in order to allow time for my body to adjust.

  3. Dave, you present a a detailed and, more importantly, very valid Argument with regard to ramp angle and skier balance. I do however take exception to your comment that nothing can be done to adjust ramp angle under bindings. It is very well established that ski racers even at the lowest capable levels adjust or have the available tools to adjust their binding ramp angles with either binding company shims or personally made shims to vary the stand height of either the toepiece or heel piece or both of their binding setup to, in fact, create any ramp angle they choose, including zero ramp angle. The boot ramp angle adjustment is, however, a challenge of a different nature, requiring much more attention and expertise. Binding ramp angle adjustment easy, boot ramp angle challenging!

    1. I am sure you are right. When I asked ski techs in various shops in Whistler about shimming binds I was told they would not touch them because of liability issues. I was also told by reps in Europe that factory techs install lift plates to adjust stand height (50 mm max under FIS rules), but they will not adjust toe-height differences. It seems to me that zeroing bindings should be possible but it is not something I do. There are other issues with binding ramp that I will discuss in future posts, one of them being that it affects boot shaft angle.

      If you have any information to offer on shimming bindings I would appreciate it.

      1. Dave, I am a Masters racer who has used Marker, Look/Rossi and Atomic/Salomon bindings my entire race career and I do know, from personal experience that those companies offer 1, 2 and 3 mm shims for both the toe and heel pieces (they are pre-drilled) and are, in fact used for legal height shimming (required when FIS started regulating stand height). But, since you can mix and match those shims, you can, after pre-determining the shim-less binding ramp angle then add the correct shims to set the binding ramp angle to zero, as well as ensuring you have the “legal” stand height! Thanks for continuing insight into the ramp angle issue. As an aside, I am in this year’s’ Atomic FIS 130 race boot and,FYI, they supply a Zeppa in 3 different flexes and, if my measurements are correct, have a 2.6 * ramp angle.

      2. Thanks for the information Graham. I get reports from reliable sources in Europe that are sometimes contradictory. It would seem reasonable that recreational bindings can be shimmed. I use a Look competition binding that has zero ramp. I didn’t realize the situation with recreational bindings until I started checking. When I ask shop techs about ramp angle, they typically roll their eyes (“Huh?”) and have no idea what I am talking about. As far as I know, the Atomic boots that Shiffrin and other racers are using is nothing like the current retail version. It is an older model that is race stock. Flex in zeppas is a big problem as in BIG problem for a number of reasons. I will post on this issue soon. When I first started talking about ramp angle of about 3 degrees, the word I got from reliable sources in Europe is that this was too steep. The ‘magic number’ was in the order of 2.6 to 2.7. When followers of my blog do their own tests, they tend to come up with this number. Bingo! You won.

      3. Shiffren’s mom Eilleen and I used to race Master’s together, and in talking to her and her brother, Taylor, at Copper Mtn this year, they did say that Shiff’s boots are an 2, maybe 3 year old model with upgraded graphics, but they also added that the last 3 years Atomic has built basically the same boot, with the last with just new (read different) graphics! I looked very closely at her boots at Copper and could not discern a visible difference. End result, who knows?

      4. When I built Langes for racers, I used to upgrade the graphics to make an older model look like a newer model. Smart racers are reluctant to fix a boot that ain’t broke. As you may recall, Shiffrin got off to a bad start in the 2014-15 WC season due to a boot and ski change. I called the boot right away and suspected the ski/binding. Over Christmas break, she changed back at a camp in Italy and I immediately saw that. She is pretty smart. But I suspect she erred and didn’t do her own testing. I have ‘theories’ as to what works and what doesn’t. But ultimately, the racer makes the call. If he or she says something doesn’t work for them, it doesn’t work period. End of story. Full stop. Back to the drawing board for me. I still think something is wrong with Shiffrin’s GS setup in her boots and/or skis. She is way too good to not be on the podium in GS.

      5. Totally concur, but knowing her focus and, more importantly, her attention to detail, she and her incredibly supportive team, they’ll figure it out. I expect we’ll see that this weekend at St. Moritz! I wish her the best, and you keep pressing forward with your research and work. I’m a fan👍

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