This post contains the most important information I have ever written on skiing. It concerns the important discovery I have made since I began to cast a critical eye on the positions of the various experts about 45 years ago; a method to determine the optimal personal ramp angle of a skier/racer.

By 1978, subjective experiments had taught me that a total ramp angle between the sole of the foot and the base of a ski of more than 3 degrees could have significant adverse effects on skier stability, balance and the ability to control the direction and especially the edge angle, of a ski. Wherever possible, I tried to limit total ramp angle (boot boards + bindings) to below or close to 3 degrees. But ski boot and binding construction often limited my ability to reach this objective. It was limitations in the construction of my current Head World Cup boot that presented challenges in getting the boot board ramp angle below 3 degrees. Through a concerted effort I had managed to reduce ramp angle to 3.3 degrees (bindings are zero) with a noticeable improvement in balance, ski and edge control. But the results of my recent NABOSO insole test suggested that the boot board ramp angle needed to be a lot lower.

The Dynamic Ski Stance Theory

A standard test of the human balance system is to subject a subject to dynamic changes in the platform under their feet. Over the past few years, I made numerous attempts to find the optimal ramp angle for skiing. One method involved assuming my strongest stance on a hard, flat level surface then stepping onto a plate shimmed to a fixed angle then repeating the process with the plate shimmed to a different angle. The results were inconclusive. Every time I went back to the hard, flat level starting surface my balance system seemed to reset. I had to get the angle of the tilted plate well over 3 degrees before I began to sense obvious instability. This led to my positing of a theory that the angle of a plate that a skier is standing on needs to be changed as the skier goes through a stance protocol designed to test stability and what I call a rooted or grounded connection where the skier feels as if their feet are literally rooted in the snow.

Research is Urgently Needed

Before I go any further I want to stress that I believe that an idea, no matter how compelling, is nothing more than a theory until it has been thoroughly tested and has withstood rigorous scrutiny. Even then, no theory should be immune to challenges. Research on this subject is urgently needed and long overdue. With this in mind, I designed the dynamic stance assessment device so it can be easily made with reasonable skills and readily available, inexpensive materials. I have recently completed a 4th generation prototype to serve this end. But a much more sophisticated device can and should be made and used by academic researchers. A servo motor driven ramp with a data acquisition package is the preferred option.

Stance Training is Essential

In order to obtain accurate results with the dynamic stance assessment ramp it is essential that the subject being tested undergo kinesthetic stance training and follow a protocol during testing that is designed to help the subject assess the effect of changes in ramp angle. It is disturbing that few of the skiers tested so far have a kinesthetic sense of the elements of a strong stance. Most have never sensed a strong stance. Worse, no ski pro or coach has ever discussed this crucial aspect of skiing with them. It appears as if it is simply assumed that a skier will automatically find their optimal stance. I can unequivocally state that this is not the case.

Dynamic Stance Ramp Test Results

  • The majority of skiers tested so far were most stable at ramp angles between 2.0 and 2.5 degrees.
  • A number of skiers, myself included, were most stable at close to or under 1.2 degrees.
  • One skier was most stable at 1.6 degrees.
  • One skier appeared to be relatively insensitive to ramp angle until it was above 2.8 degrees.
  • After training, most skiers were sensitive to changes of 0.1 degrees.
  • No skier tested so far was stable over 2.8 degrees.
  • Adding NABOSO insoles further reduced the ramp angle.

I tested most stable at 1.2 degrees; 2.1 degrees less than my existing boot board ramp angle. In order to reduce the boot board ramp angle to 1.2 degrees, I had to raise the toe end of my boot board 9 mm and lower the heel 2 mm for a total reduction of 11 mm.

First On Snow Impressions

Walking in my ski boots with the corrected boot board ramp angle immediately felt different. But the huge impact didn’t come until I started moving over the surface of the snow on my skis. Then the whole world seemed to change. I had a huge deja-vu moment; one that took me back to the solid, stable feeling I had under my feet in my first low-cut leather plastic soled ski boots. It was then that I realized that it was the jacked up heels of my first all plastic, rigid shell ski boots 45 years ago that had destroyed my balance and confidence on skis. This is a big miss for the ski industry, one that should have been caught by those who promote themselves as the experts in skiing, but wasn’t. This miss has huge implications for skiers at every level and ability all the way up to the World Cup. A skier, but especially a racer with a sub-optimal ramp angle will revert to an unstable weight on the heels, back seat Defensive Stance in which the skier is incapable of recruiting the enormous power of the glutes and optimal sensorimotor processes.

First generation device in action. Ratchet socket wrenches raise the ramp by turning bolts set into T-Nuts on each end.

Digital SmartTool electronic level accurate to 2 decimal places

Fourth Generation Stance Ramp assessment prototype. Two x two wood stiffening elements added to the platform.

The skiing of those whose ramp angle has been optimized is elevated to a whole new level provoking immediate comments like the difference is ‘night and day‘. After my transformation, I now believe that until ramp angle is optimized, everything else is irrelevant and that no amount of footbeds, orthotics, cants, alignment or custom fitting can overcome the adverse affect of sub-optimal ramp.


  1. Hi David,

    Thank you for your replies. I have been and will continue to practice the tensegrity/stretch reflex stance and test ramp angles. As you suggested boot room over the instep is limited (for adding forefoot shims) so I may have to find a different boot to modify. I found an old pair of Atomic Race Tech boots which have a decent liner and a tongue which feels much better than either the Lange World Cup tongue or the old San Marco tongue (which is similar to the Head tongue dissected in your “Reducing Forefoot Crash Space” post. Exactly what i am trying to do. Applying more pressure on top of the tongue does not seem to help and crushes the dorsal pedis artery reducing circulation. Thus, my interest in the dorthotic and how to build one. Am I right in thinking that you do not need too much pressure on the forefoot tongue if the shape conforms well to the individual’s instep? From your patent, it seems that you used thermo formable foam with a thermo formable plastic shell over the top. What type of plastic is used for the shell? How firm is the foam used? I have a piece of 6.85mm firm blue thermofoam which I hope is similar to the padding on the tongue shown in “Podborski’s Balancing Act”. Are the thermoforming temps the same for plastic and foam and what type of glue is used?

    I am curious about what you suggest for heel fit. There is almost no mention in any of your posts regarding this. When employing “prior art” fitting the heel is such a big focus and terms like “locking down the heel” are common. Does it become a non issue when the other elements of this method are properly applied? I have felt quite a bit of lateral heel play. I removed all the padding on the medial side of the liner and it feels pretty good otherwise. I never thought I would be doing that to a liner when I couldn’t get my boots tight enough to keep my foot “immobilised, locked in, etc.” as I have loose type ligament structure. The post on Tight Feet Loose Boots, Loose Feet Tight Boots really hit the nail on the head for me.

    Sorry about all the questions but, I am getting close and feeling the anticipation. Wait, that was a technique in the late 60’s early 70’s wasn’t it? “Anticipate the turn by rotating the upper body, then flattening and twisting the skis into the new direction…” Would it be better to communicate via e-mail regarding these fitting questions?

    Thanks again for you help,

    1. Herb,

      Thank you for your insightful comments. The issues you pose provide an opportunity for the kind of constructive narrative that I started this blog to encourage. I will write a series of posts that address each of your issues individually.

      For now, I will uequivocally state that I believe most of the problems caused by ski boots such as instability of the foot and leg in the boot and heel spurs can be attributed to excessive zeppa-delta ramp angle (which appears to be more than about 2.2 degrees or even much less); in other words bad design. For this reason, I think it unlikely that the ski industry will take any steps to address this issue in the near future.

  2. Hi David, In my previous comment I should have said ” It is absolutely critical to get net ramp angle and shank/cuff mobility as close to optimal as possible to appreciate the potential of the mods” .
    Also, should have said “WE have proven him wrong…”
    In addition, I am interested in the urethane casting material and methods as I am modifying an Alpine touring boot with toe spring and a cabrio/three piece shell design. I cannibalised old cork custom foot beds, microwaved and rolled out the cork to make a 7.5mm slab fitted to the met area, trimmed out the arch form in the shell, and replaced/lowered the heel pad to get to 2.5 degrees. The boot board is nearly flat both ways. Tech bindings can have ridiculous delta, 16mm on one Dynafit set, plus the toe and heel boot inserts are different heights (the wrong way), so massive toe shims on the skis to get to where I could confidently if not perfectly accurately measure net ramp angle with the boot mounted on the ski. I use a block of wood with an arch cut into the bottom so that it contacts the met area and the heel only and a square and small digital level and check, check, check for repeatable consistent readings. This boot is my test mule to prove the effectiveness of your principles and learn how to modify boots Manifesto style. As you said, the liners are the biggest problem to modify. I concur!
    Your latest posts have energised my work so I will test lower ramp angles on my stage 1 ramp angle platform. I have a Skiers Edge exercise machine which has adjustable ramp angle foot platforms. Do you think it would be helpful to test ramp angles on that as a dynamic skiing simulation?
    It has taken a lot of time and effort as I am not a boot fitter, but the results have been very promising. I was amazed at how much easier it was to balance when skiing with the lower ramp angle and more freedom in the cuff. I have been skiing for over 50 years and this is revelatory.
    The stretch reflex and tensegrity ideas really work and can be applied directly to my Tai Chi practice which helps practice balance while moving. The principles seem to widely applicable.
    Dare I say, I can’t wait for the book? It would blow all previous works such as How the Racers Ski, The Athletic Skier and the ski/boot/binding/stance/technique ideas in many others out of the water. I was looking hard for a way to fit boots which coincided with the barefoot concept and fortunately found this website. My feet were killing me after skiing in boots with footbeds and Intuition liners and then going back to barefoot and I was totally frustrated with my barefooting boot fitter (ex-boot fitter).

    Thank you sincerely,
    Herb Jones

    1. I agree that the issue is finding optimal total ramp angle. In order to properly assess BB ramp (zeppa), binding ramp (delta) is best kept at zero or close to it. It seems to make sense to have a small amount of zeppa because it would appear that this would stimulate muscles responsible for stability. But as I have stressed, research is needed and long overdue. Until there is quality data, this is just a theory.

      I will be posting soon on poured in place boot boards. In the meantime, here is a link to one of the products that has worked well – https://www.smooth-on.com/products/smooth-cast-385/

      I have not given the Skier’s Edge device much consideration because the side to side movement pattern and the center hinged platforms bear no resemblance to the mechanics, neurobiomechanics and physics of a properly executed ski turn.

      I started to write a book several times but gave up because skiing is drowning in a sea of misinformation and disinformation, much of it founded on nothing more than uninformed opinion that makes a good marketing story that appeals to the masses.

      More later.

  3. Hello David,
    I understand that this Manifesto is ” just” the ski portion of your body of work and this is an incredible achievement. I have been attempting to apply your principles to my equipment set up with some very positive results. Ramp angle and cuff mobility are absolutely critical to get close in order to appreciate the potential of the mods. For the first time that I can remember I had no sensation of back seat balance issues and could ski reasonably well with no cants or heel elevation add-ons in or out of the boot. Went from 9+ degrees of NRA to about 2.5 and 3-4 degree cants on both skis to 0 and felt incredibly solid and comfortable on my skis. I’m still having some tongue/forefoot hold issues as my feet do not feel planted on the boot board and the fit feels sloppy in the heel so that I am not quick and reactive in short radius turns.
    Any chance of discussing these issues? I am trying to build a dorthotic tongue system and doing the fitting myself as my boot fitter deserted me after turning me on to barefooting!!?? He said your fit methods could not work and that ramp angle is a not an issue and footbeds were necessary, Ha! and the guy used to run 3 mi to work literally barefoot! I have proven him wrong and he is history.
    Can’t thank you enough for making this hard won information so generously available.

    Thanks again,

    1. Hello Herb,

      Thank you very much for your comments. While I try to avoid confrontating those such as your boot-fitter who deserted you, after hearing an endless string of stories such as yours, I can’t help feeling that the inmates have seized control of the insane asylum.

      “I’m still having some tongue/forefoot hold issues as my feet do not feel planted on the boot board and the fit feels sloppy in the heel so that I am not quick and reactive in short radius turns.
      Any chance of discussing these issues?”

      Of course. This is why I write this blog. The first thing I would suggest is to try reducing the ramp angle of your boot boards further. If you have room in the forefoot, try adding 2 to 3 mm (1/8 in) shims made of gasket cork or any dense, non compressible material. Card stock will do in a pinch. If raising the forefoot does not feel worse than your current 2.5 degree ramp keep going down in slow stages. I still cannot believe that I tested strongest at 1.2 degrees and especially the dramatic effect it had on my skiing, like nothing I could ever have imagined!

      I also suggest you spend a lot of time rehearing your stance per my recent posts.

      As for your ex-boot fitter who said my fit methods could not work, here is what Nancy Greene, Canada’s most famous skier, said about me in 1978, ten years after her amazing Olympic performance:

      “I am somewhat emotionally involved, having found personally a tremendous improvement in edge control and (ski) feeling with the foot beds (I made for her) in (her ski boots).”

      Forty years later, I am light years ahead of what I knew (and didn’t know) back in 1978.

      Where possible, I try to provide material and concepts that are easy and economical so those who wish to can do their own work such as you have done.

      I will post on your requests soon.


  4. Hi David, as always excellent informations shared with all of us (I am always eagger to read more from you and I have already naboso 1.5 in my liners but still a 4° ramp in my boots. ..). Could you tell us a bit more on hereafter prerequisites “kinesthetic stance training and follow a protocol during testing” so that we can give a try by our self and I can estimate my own angle ? Would be fantastic to get your help here.

    1. I will be posting on the stance training protocol later today or tomorrow. Based on my latest analysis and theory on the effect of ramp on skier stability and ski and edge control a 4 degree total ramp would place even the most athletic and/or acrobatic skier well beyond the limits of stability.

      1. No doubt about it and interestingly I am now equipped with the Carv system and my main deviation with respect to required positions and actions is the fore/aft position where I am way too much on the front and I feel that very clearly now.

      2. Hi David, replying to your question on Carv (i cannot hit reply button in the section bellow …). My run scores are always mainly negatively impacted by the “Balance Score” (see 1st capture hereafter) and when looking into the details, optimum fore/aft balance is considered to be around 60% on the Front (ball of the feel when initiating the turn and heel when finishing it) and i am more around 75% (76% in the second capture attached here) … I have asked questions to Carv team and especially how to get a view of the pressure all along the turn (as displayed on iTunes) but i haven’t received any reply so far … Snapshot 1 : https://drive.google.com/file/d/1aEM5lVGqHzjMvgfejSXnc8Iq8cvxZ4LE/view?usp=sharing Snapshot 2 : https://drive.google.com/file/d/1OEBfixN3pZWCqnFqA3E-Ty29ER3JJFU1/view?usp=sharing

      3. “……. balance is considered to be around 60% on the Front (ball of the feel when initiating the turn and heel when finishing it) and i am more around 75%….”

        Balance cannot be ‘considered’. There must be a strict criteria for balance in a turn sequence in order to rate balance as a postural response and not an act of managing to stay upright.

        A turn starts as a skier exits the fall line and creates a force with their skis that opposes the force of gravity. The skier must establish postural balance over their outside ski as they enter the fall line. Impulse loading establishes pressure on the ball of the outside foot which is maintained through the load phase which is actually the turn.

        The transition to the new outside starts as soon as weight transfer is initiated from the outside (downhill) ski to the inside (uphill) ski. This releases the load on the outside ski causing the pressure to move rearward under the heel. Studies done of pressure under the feet of skiers have failed to recognize this pattern because the studies were done without the benefit of a physioligical model which would have predicted this pressure pattern.

        “……. I have asked questions to Carv team and especially how to get a view of the pressure all along the turn…”

        You are correct. You need to be able to view the pressure through the entire turn sequence on both (feet) skis. It sounds like CARV may have a software issue.

  5. It is a similar idea of the earth shoes which keeps your skeletal alignment correct the same as walking barefoot in the sand. I have no height under my heal but have a slight rise under my toes which has stopped any knee or hip pain. I ski in walk mode and barley pressure any buckles. It allows me to find balance easily and makes stand centered in your ski boot.

    1. I had a pair of the original Earth Shoes. I don’t believe they kept the skeletal alignment correct. The inventor was a yoga teacher who claimed certain benefits which as far as I know were never supported by theory or any studies. The issue with ski boots is that ramp angle appears to be critical and highly individualized. There was no reason to assume ramp angle would not have a profound affect on skier balance and control of the skis, especially edge control or that one size would fit all. The fact that there does not appear to be any standard in the industry for either boot board (zeppa) or binding (delta) ramp angle suggests that this critical aspect was never even considered.

      I went from 3.3 degrees zeppa (delta zero) to 1.2 degrees and am considering trying a slight negative (toe up) ramp. I also ski with my buckles and have no sensation of anything on my feet. All I am aware of is the pressures under my feet. So I think you are definitely on the right track.

    1. I am not aware of a single study that validates static alignment of body segments achieved with cants or for claims made for footbeds in terms of them creating a foundation for the foot. The principles on which lateral alignment is based are not supported by principles of mechanics and biomechanics and especially sensorimotor principles. The angle of any ramped surface between the plane of plantar foot and plane of the base of a ski has very significant effects on neuralbiomechanics. Ramp angle has profound dynamic, not static, implications.

      The neutral ‘theory of foot function’ which is the cornerstone of most orthotic/footbed principles has been thoroughly discredited.

      Challenging the foundations of the clinical model of foot function: further evidence that the root model assessments fail to appropriately classify foot function – https://jfootankleres.biomedcentral.com/articles/10.1186/s13047-017-0189-2

      None of the deformities proposed by the Root model were associated with distinct differences in foot kinematics during gait when compared to those without deformities or each other. Static and dynamic parameters were not correlated.

      Taken as part of a wider body of evidence, the results of this study have profound implications for clinical foot health practice. We believe that the assessment protocol advocated by the Root model is no longer a suitable basis for professional practice. We recommend that clinicians stop using sub-talar neutral position during clinical assessments and stop assessing the non-weight bearing range of ankle dorsiflexion, first ray position and forefoot alignments and movement as a means of defining the associated foot deformities. The results question the relevance of the Root assessments in the prescription of foot orthoses.

  6. David, This is all fascinating. THANK YOU for all the effort, and the public sharing of information. You have made a tremendous improvement in my skiing, and thereby the pleasure derived.

    I found your blog searching for information that I could use to help my wife continue to ski with significant ankle issues. As a dentist with a physics background, your trials and results have created a new paradigm for me. The engineering and biomechanics make logical sense.

    I’m experimenting with myself first. I have completely flattened my footbeds, ski with only the first notch engaged on the upper most buckle, removed the power strap. Wow!!! My skiing has leapt forward in level and energy required. I am an adult survivor of congenital heart disease (and resultant surgery), having limited exercise capacity. You have allowed me to ski better, and with so much less effort, that skiing is now so much more fun. I feel like you’ve “given my skiing back.”

    I’m working on stance training, and developing ‘foot feel’ that I did not have before with tight/locked-down ski boots. My balance in irregular snow conditions is improving rapidly.

    Next up is a partial glossectomy (in my area of expertise) and having the boot shell expanded so my metatarsal heads can fully splay when loaded.

    I would be grateful to have more information on stance protocol, as to assess my own stability. I would like to begin looking at may own reaction to ramp angle, and will be constructing an incline as you have shown.

    Lastly, I would like to get your opinion on how I can help my wife. Email?


    1. Robert, thank you for your kind words. It is stories like your that make what I do worthwhile. I can honestly say that at this point in my life in my retirement years, my wife and I are skiing far better with much less effort and more fun and enjoyment than I had ever dreamed possible. We are experiencing what skiing can and should but unfortunately isn’t for the majority.

      I have benefited enourmously in terms of understanding the subtleties of stance in my recent work with the dynamic stance assessment device. I will be revising my previous posts on stance and republishing them soon. I will also be posting on how to construct and use the dynamic stance assessment device and will update on this as I glean more information from testing.

      Insofar as assisting you with your wife, I will contact you by email.

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