TO SUPPORT OR NOT TO SUPPORT THE FOOT?


To support the foot or not support the foot? That is the question and the subject of this post.

Some followers of this blog are asking  whether they should use custom insoles, aka orthotics or footbeds, in their ski boots. My views on issues pertaining to the structures of ski boots and interventions in general that affect the physiologic function of the user are predicated on whether they accommodate and support the physiological processes of the user and especially whether the proponents of specific structures and interventions can support their positions with explanations predicated on sound principles of science and especially whether the explanations will withstand intense scrutiny. In addition, any explanations, conclusions or claims made should be based on the actual environment in which the use is occurring. Conclusions made in an indoor environment, or even in a controlled laboratory setting where gravity is the sole external force acting on the subject or subjects, cannot necessarily be applied to skiing maneuvers where the forces are both three-dimensional and dynamic in nature.

The question of whether the foot should be supported or not in skiing can only be answered by putting the issue under the high powered lens of the microscope of sound science.

14 comments

  1. DR. HEWSON’s COMMENT IS IN RESPONSE TO DR. STEINBERG’S COMMENTS
    Your biomechanics of “too much deformation of the STJ” are self serving. Normal medial STJ movement of the talus is followed by a mandatory normal 1:1 coupling of the tibia to encourage normal internal leg rotation and normal dorsiflexion of the ankle. This normal coupling mechanism produces a synergistic postural response enhancing internal rotation of the entire leg. Normal pronation is NOT deformation. Pronation is not evil. Lighten up.

  2. What do you personally use David? I know you had an influence on me throwing my footbeds away and pursuing biomechanics more deeply to understand how I can create stability and power through my own body. I believe that if the individual understands how to utilize Efficient mechanics along with technique then footbeds only get in the way. However, it’s a long process getting your brain to be that in tune with how your body can function on such a natural level. Especially if the brain has been told that it needs support from an external device and that it should rely on this for support. Not our own in built support system.
    Just my own thoughts through personal experience of feeling the differences of external foot support(footbed) and internal foot support (whole body interaction with environment).

    1. Tom, I don’t use anything under my feet in ski boots except a dead flat insole. In fact, I go to great lengths to ensure nothing impinges on the arches. When indoors I rarely have anything on my feet. There are some excellent papers on exercises that develop the intrinsic foot muscles that support the arch and studies that show that the foot is designed to respond to stress by becoming stronger. I will post links to these papers in the future. An excellent book on this subject is The Biomechanics of Sports Shoes by Benno M. Nigg. The book can be ordered from NiggShoeBook@kinucalgary.ca

  3. I feel this somewhat depends upon foot structure in the training environment. If the foot is too unstable, training activities loose power and strength adaptation. So, in one situation, footbeds or orthotics are advisable in everything. In another situation, they are advisable in in one of the other.

    It’s not only an issue of movement in the boot, and being able to direct and feel the movement, it’s also an issue of potential foot colapse (in a rough sense), during the turn and resultant forces.

    My personal thought is if you need correction in athletic shoes, then something in your ski boot is a good idea. However maybe it is a simple as those skiers who rely more on kinesthetic feedback using a device which has some movement, and possibly those who styles “muscle through” the turn without attention to this feeback loop could possibly use a more rigid device.

    As implied in the post, this has not really been studied and warrants some investigation to determine some decision-tree pathing about different skiers, their styles, physiological levels and then, oh yes, their feet!

    1. If a foot appears to be unstable (according to who and what?), the question that needs to be asked is why is it unstable? Some form of support can be quite effective in relieving pain from plantar fasciitis. But it doesn’t address the cause of the condition. So support for the arch acts in the capacity of a crutch by preventing the plantar fascia from doing what it is intended to do. The concept of claiming to support a foot on a platform that is not just inherently unstable, but unstable in the direction of inversion, such as occurs on the outside foot of turn, is a contradiction in terms because the platform is only supported on a the narrow edge of its medial or inside turn margin. There is literally so support for support under the remainder of the foot. So claims that the foot can be supported in this environment are without a leg to stand on.

      1. There are very precise biomechanical descriptions of what an “unstable” foot, is, and how to perform a thorough biomechanical examination to measure it, when it exists. This includes measuring the rearfoot to forefoot alignment.

        You fail to understand the difference between a functional orthotic, and an accommodative orthotic. Custom molding of either, does NOT create a “crutch”. An unstable subtalar joint is NOT due to a weakness of muscles, tendons, or ligaments. An unstable STJ is due to the specific shape of the joint between the calcaneus and the talus, and that is an inherited trait!

        The contradiction in terms, you refer to, is due to the way you use them!! DPMs understand the functional biomechanics of both the medial and lateral columns, and the STJ. Your comments tell me you do not understand any of this.

        I don’t fault you for not understanding functional biomechanics, but I do fault you for claiming you do. Your base knowledge comes from 60 years ago.

        The foot can, and should be supported, in an alpine ski boot. To suggest otherwise, is absurd.

      2. For some reason, you seem to be ignoring the consequences of Newton’s Third Law. The issue is not what you place under the arch of the foot that is in question. It is the fact that the platform under the foot that is being supported will be inherently unstable when the ski is in edge because an offset will exist between GRF at the inside edge and the load W. Any two year old who has deliberately slid off a teeter-totter when their end was on the ground and their playmates’ end was at the upper limit learns the consequence of an unbalanced moment of force as they watch their playmate drop to the ground. Teeter-totters are no longer seen in playgrounds because it is well-established that unbalanced moments of force have the potential to cause injury. The question I have for you is What side of the inside edge are you on?

      3. Regarding Newton’s law (taken out of context):……….
        Your analogies make zero sense. You arrived at your conclusions, without having all the information, and you won’t admit it. It is this basic lack of foundation knowledge, that has blinded you to any other view than the one you created, a number of years ago. Your theories are unproven. You have failed to keep up with current biomechanical science. You’re trapped by what you think you know, and are unwilling to change.

      4. You seem to be forgetting that at my insistence scientists were commissioned in 1991 to design a research vehicle to acquire data on skier biomechanics and balance processes during actual ski maneuvers and either prove or disprove my hypothesis. The cost of these studies was approximately $140,000. My involvement was strictly as an observer. The results of the studies validated my hypothesis. The outcome determined whether a program to develop a ski boot based on sound science would go forward. To the best of my knowledge, no one has done similar studies. including yourself. Until you can produce a thorough explanation of your hypothesis supported by hard data acquired during actual ski maneuvers your hypothesis will remain exactly that.

      5. Remember, WC skiers are generally way above the average in physiological integrity and athletic prowess. What works for them should not be a model for the average skier without those structural features and much less coordination. This goes for feet as well.

        What they can do or should do is only a partial directional pointer to what other skiers might or might not do. With WC skiers, these discussions are probably more about performance, with less skilled skiers, a component of comfort, at least from their perspective should be considered. While it appears you don’t like subjective observation, I would note that in my world footbeds and orthotics have been far more a help than a hinderence. I addition, the thread about foot structure and knee alignment/potential wear is very important for the general population.

        I agree with Dr. Steinberg, there are some people who have the ideal athletic foot, no matter what the sport which allows optimum movement, sensitivity and power and force application. However, the number of people I have met with this foot is few, and they tend to play in the NBA and NFL as well as other high-level sports. It’s the course of action for the average to better skier that is the discussion point.

      6. I suggest that you read my post IMITATION GAME: RUSSIAN FEDERATION VERSION. What you seem to be implying is that the human balance system is incompetent unless one is a skilled athlete. The data metrics captured by the Birdcage dispute your position which is pure speculation. When you have data such as the Birdcage captured during actual ski maneuvers that showed that the CNS of neophytes skiers could do what World Cup and Olympic champions could do, we can have a meaningful discussion. To paraphrase Shakespeare, “The fault my dear Wolkodoff lies not in our CNS but in the ski equipment that renders it ineffectual”.

  4. Sorry, but all you offer is an uneducated opinion of how you…. think…….the foot and ankle functions, in whatever enviroment it is in. It’s all pure conjecture. You continue to “question” whether it is better to have an unsupported foot compare to a supported one. You do not fine tune what you mean, biomechanically, as to your definition of a “supported” foot.

    Bottom line, in my expert opinion (by education, testing, 4 year doctor of podiatric medicine degree, license, thousands of hours of direct observation and hands on experience, and continuing education meetings), unless you were born with high-arched, rigid feet, a foot must be supported in a ski boot. With that said, I am not talking about locking the subtalar joint, which I believe is what you think a ski boot insole does. I have seen, mostly with Superfeet moldable insoles, that the boot fitter, had supinated the foot, during the molding process. Doing this rolls the foot out (supination), allowing a too high of an arch to form in the insole. This disaster is rigid.

    1. Given the two options for load transfer, off set medial or lateral of the inside edge of the outside ski (assuming this is within specific limits), I see the central issue as how any intervention affects the ability of the two load transfer options. Unless the joints of the foot are fused with the STJ in a neutral and, in turn, fused to the tibia this would only serve to prevent the STJ from articulating. It would not eliminate the inversion moment of force that will the unavoidable consequence of preventing the foot from probating sufficiently to transfer the load to the medial aspect of the inside edge. Until someone can renegotiate the fundamental laws of the universe, this will not change. This issue has to do with physics and mechanics. How the foot and ankle ‘works’ is irrelevant.

      1. Re: Options for load transfer: In the skier with a STJ neutral foot, held that way by an orthotic, using the appropriate amount to resistance to counteract plantar pressure through the medial column and the forefoot properly positioned, …..load transfer is more instant, smooth, and reproducible, .Another way to think about this is that you know where your edges are. I control the amount of STJ pronation I want to have available, by controlling the movement of the calcaneus and talus. Remember, I have always said, I do not lock the STJ. I also take into account the amount of STJ movement available from the deformation of the soft tissue, beneath the arch, at maximum pressure, and taking into account height, weight, athletic ability and skier type.

        You keep falling back on physics and mechanics, as a crutch to support your theories, instead of learning about functional biomechanics. The laws of the universe, according to you, seem to be your attempt to distract us from your lack of understanding of the tri-plane motion of the STJ, under varying conditions and varying uses.

        The knee sits on top of the tibia, which sits on top of the talus, which sits on top of the calcaneus that creates the STJ. Do I have to draw you a picture? Too much deformation of the STJ, internally rotates the tibia, causing medial tipping and internal rotation (twisting) of the knee and mal-tracking of the patella. I guess you missed….The foot bone is connected to the ankle bone; and the ankle bone is connected to the leg bone, and the leg bone is connect to the thigh bone; nursery rhyme :-))) In short, a collapsing arch causes rotational torque, at the knee. The pain does not start until you cause enough cartilage and meniscus damage.

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