human feet

BEYOND BIOMECHANICS BY DR. EMILY SPLICHAL

The following post appeared on the Evidence Based Fitness Academy (EBFA) fitness blog on February 6, 2018 under the title Beyond Biomechanics | Addressing Foot Pain with Sensory Stimulation (1.).

I have reproduced the post with the kind permission of Dr. Emily Splichal under the title Beyond Biomechanics by Dr. Emily Splichal because her emphasis on the role of sensory stimulation of the plantar foot on foot, lower limb and function of the entire body has both direct application to and implications for, skiing.

I have a theory on what I call The NABOSO Effect that explains how I think NABOSO insoles improve dynamic stability in the biokinetic chain that I will discuss in a future post. I have been testing NABOSO 1.0 and 1.5 for months.


Beyond Biomechanics | Addressing Foot Pain with Sensory Stimulation – by Dr. Emily Splichal

I want you to picture a human foot.   Now picture a person standing barefoot, and then walking barefoot.   Do you see the foot striking the ground and flexing under impact, only to re-stabilize and push off just a few milliseconds later?

Often times when we think of human movement we can’t help but to be drawn to the thought of joints moving and muscles contracting.   Or in the case of foot function we are quick to consider the mechanics of flat feet, high arches, pronation and supination.   However when we delve deeper into the science of human movement there is more than meets the eye.

The Two Sides of Foot Function

When I teach on behalf of EBFA Global or speak to my patients I always emphasize that there are two sides to foot function (and dysfunction) – biomechanical and neuromuscular.    Now both play an important role in foot function which means that both must be appreciated – however to solely treat foot pain with just one belief system in mind is inherently flawed.

In most Podiatric Medical Schools we are taught foot function and foot pathology solely from a biomechanical perspective.

This means that every patient is tested for foot mobility and told to stand statically to determine arch height and foot type.   Based on this foot-focused biomechanical assessment and foot classification system the patient’s cause of injury and treatment protocol is determined.   Some of the favorite treatment recommendations include motion-controlled footwear and custom-posted orthotic both of which are prescribed with the hopes of controlling foot-focused biomechanics and thereby reducing their foot pain.

Beyond Biomechanics

The other side of foot function is one that is driven from a neuromuscular perspective and integrates the science of sensory stimulation and fascial systems.   In the case of neuromuscular function every patient would be assessed for sensitivity of plantar mechanoceptors as well as co-activation patterns between the foot and the core.  The role of minimal footwear, myofascial releasing, breathing patterns and compensation patterns more proximal would all be considered.

So which is more appropriate?  Well it depends.   In certain cases there will be a stronger argument towards a more biomechanical influence and in others it is more sensory.  This means it really is a marriage between the two approaches that provides the greatest patient outcome.

Sensory Stimulation in Foot Pain

My practice and Podiatry career is built around bringing an awareness to the important role sensory stimulation has on foot function and foot pain.

With every step we take impact forces are entering the foot as vibration.  This vibrational noise stimulates unique mechanoceptors on the bottom of the foot and is used to coordinate the loading of impact forces through coordinated contractions of the intrinsic (small) muscles of the bottom of the foot.   This co-contraction leads to a stiffening or strengthening response of the foot.

Researchers such as Nigg et al. and Robbins et al. have demonstrated a direct relationship between sensory stimulation of the plantar foot and intrinsic muscle strength concluding that one is necessary for the other.   This means that if our footwear or orthotics disconnect us from sensory stimulation – as in the case of cushioned footwear – this can actually weaken our foot making us susceptible to plantar fasciitis, Achilles tendinitis and stress fractures.

Beyond Vibration Stimulation

Vibration stimulation is an extremely important sensory stimulation that enters our foot however it isn’t the only stimulation.   Another important stimulation is the ability for our foot to determine texture and if a surface is rough or smooth.   This information is used to help maintain dynamic balance (think walking on ice).

Enter the merkel disk mechanoceptors.   These superficial sensory nerves are used to determine what’s called 2 point discrimination which is translated to roughness or the texture of a surface.  Surface texture and insole texture is one of the most studied aspects of foot stimulation and posture or gait.  From decreased medial lateral sway in patients with Parkinson’s or MS to reduced prefrontal cortical activity in atheltes post-concusion the applications are promising!

One area that hasn’t been focused on for sensory stimulation and foot function is foot pain.  I am here to change the awareness around this concept and share the powerful application of sensory stimulation and foot pain.

As we mentioned earlier sensory stimulation of the foot leads to a contraction of the intrinsic muscles of the foot.   Intrinsic muscle contraction is not only a criticial step in the damping of impact forces but has also been shown to increase the medial arch and build co-activation contractions in the core.

 The Evolution of Textured Insoles

In October 2017 Naboso Technology launched the first-ever commercially available textured insole!   Naboso Technology essentially brought the science of touch and years of textured insole research to the market place giving new hope to people with foot pain.

Available in two strengths – Naboso 1.0 (1mm texture) and Naboso 1.5 (1.5mm texture) Naboso Insoles are designed to be worn without socks (or at the most very thin socks).  They fit into all footwear, are freely movable in all planes of motion and are only 3mm thick.

FROM THE GROUND UP

Are you barefoot strong?


Learn more about the power of texture! – http://www.nabosostechnology.com

  1. https://barefootstrongblog.com/2018/02/06/beyond-biomechanics-addressing-foot-pain-with-sensory-stimulation/

 

NABOSO SURFACE SCIENCE INSOLE UPDATE

In June of this year, I posted on my beta testing experience with NABOSO surface science, small nerve, proprioception stimulating technology (1.).

Recently, I received the consumer version of NABOSO called NABOSO 1.0 shown in the photo below.

NABOSO 1.0 has a tighter grid than the NABOSO beta version I have been testing. The pyramid-like texture is also smaller.

The photo below shows NABOSO 1.o on the left and NABOSO beta on the right. The photo was taken before I trimmed NABOSO 1.0 to fit my shoes. 
Here is the information that came with my pair NABOSO 1.0 insoles.

I use both NABOSO 1.0 and NABOSO beta in my Lems Primal 2 and Xero Prio shoes. I immediately sensed better balance with the tighter grid of NABOSO 1.0. But I found it interesting after going back to NABOSO beta, after a period of time in NABOSO 1.o, that NABOSO beta felt more stimulating. Based on this subjective experience, I think there may be some advantage to switching back and forth between different texture grids. Hence my interest in the new NABOSO 1.5.

NABOSO 1.5 can be pre-ordered now for a reduced price of $30 US at orders@nabosotechnology.com

Disclosure: I do not receive any form of compensation from NABOSO or Dr. Emily Splichal. Nor do I hold any shares or have any financial interest in the company. The sole benefit I derive from NABOSO is to my feet and my balance and the efficiency of my movement.

I will be testing NABOSO insoles in my ski boots this winter in conjunction with toe spreaders starting with NABOSO 1.0. I will report on my experience in a future post.


  1. http://wp.me/p3vZhu-27v

NABOSO PROPRIOCEPTIVE STIMULATION INSOLES

For several weeks, I have been testing the first-ever small nerve plantar proprioceptive stimulation insole technology called NABOSO, which means “barefoot” in Czech. The surface science technology was invented by Dr. Emily Splichal and is being marketed by her in conjunction with NABOSO yoga mats and floor tiles.

Introducing Naboso Insoles by Naboso Barefoot Technology. Get ready to experience what it truly means to move from the ground up with the first-ever small nerve proprioceptive insole to hit the footwear industry.

The skin on the bottom of the foot contains thousands of (small nerve) proprioceptors, which are sensitive to different stimuli including texture, vibration, skin stretch, deep pressure and light touch. When stimulated these proprioceptors play an important role in how we maintain upright stance, activate our postural muscles and dynamically control impact forces. – Dr. Emily Splichal

http://nabosotechnology.com/about

Dr. Emily Splichal goes on to state:

The skin on the bottom of the foot plays a critical role in balance, posture, motor control and human locomotion. All footwear – including minimal footwear – to some degree blocks the necessary stimulation of these plantar proprioceptors. The result is a delay in the nervous system which can contribute to joint pain, compensations, loss of balance and inefficient movement patterns.

Naboso Insoles are backed by surface science and texture research – and have been shown to not only improve balance but also positively impact gait patterns, ankle proprioception and force production in athletes.

Dr. Splichal stresses that:

This (NABOSO insole) is an insole providing proprioceptive and neuromuscular stimulation – it is not an orthotic providing biomechanical control.

http://nabosotechnology.com/naboso-insoles/

The principle proprioceptive neural activity associated with balance responses occurs across the plantar plane. It is strongest in the 1st MPJ (big toe joint) and big toe.

Dr. Splichal cites studies that found that textured insoles increased the activity of receptors in the plantar surface of the feet with a significant, immediate effect seen in the outcome measures of static (weight bearing) and dynamic (weight symmetry index, strength symmetry) in balance tests  as well as in gait symmetry (single support and swing phases). Thus, the proprioceptive stimulation benefit of textured insoles is carried over into footwear without textured insoles. I have noticed a significant improvement in  plantar proprioceptive sensitivity when barefoot or when my feet are not bearing weight. It is as if my feet have been put to sleep by a local anesthetic which has worn off.

Dr. Splichal’s information on NABOSO states that for the first time ever it is now possible to bring the power of barefoot science and plantar proprioceptive stimulation to all footwear – regardless of support, cushion or heel toe drop.

Assuming a NABOSO is trimmed, if necessary, to fit a shoe, there will be a positive effect on plantar proprioceptive stimulation. But my experience to date has been that the plantar proprioceptive stimulation will be much more pronounced in a minimal, zero drop shoe with adequate width for fascial forefoot tensioning and correct alignment of the big toe. I have experienced the best results with NABOSO in the Xero Prio shoe with the Lems Primal 2 and a Vivobarefoot model, close seconds.

The photo below shows the Xero Prio (blue-grey) with the Lems Primal 2 (black).

Both shoes have thin soles with low resiliency (the material compresses very little). The soles are also very flexible, an important quality. The sole wearing qualities of the Xero are excellent. The Xero Prio has become my all around minimal shoe. I use it for cycling on my mountain bike fit with large flat platform pedals.

The photo below is of the NABOSO insole for my left shoe.

Initially, NABOSO insoles are perceived, but not uncomfortable. After a time, shoes feel strange without them.

Over several weeks, I have done many tests of different shoes and insoles where I compare cushioned, standard insoles to NABOSO and different shoes with and without NABOSO as well as one-on-one comparisons with different shoes on each foot. After an initial walk in period, if I remove a NABOSO insole from one of my Xero Prios, it feels as if sole of the foot with the Xero without the NABOSO is signicantly less sensitive.

The most significant aspect of trying NABOSO insoles in different shoes is that it immediately becomes apparent just how bad some shoes are. The more cushioning, the narrower the fit and the greater the heel to toe elevation of the sole, the worse the shoe feels. For example, when I compared the Xero Prio with zero drop to a Nike Free with a 5 mm drop, I immediately sensed a pronounced negative effect on my posture and muscles of my legs, especially my glutes.

A Game Changer?

Prior to NABOSO, footwear companies could make shoes that have a negative affect on posture, balance and gait because it could be argued that the benefits of protecting the soles of the feet from mechanical damage outweigh any negative effects on balance and increased susceptibility to falls and injury. But the criteria for product liability is that a product must minimize, but not necessarily eliminate, the risk of injury to the consumer. Studies of textured insoles and even thin, low resilency soled footwear have shown dramatic improvements in balance and gait while reducing the risk of falls and potential injury. The inescapable conclusion is that footwear that reduces balance and the efficiency of gait while increasing the risk of falls and potential injury fails to meet this standard. This raises the question, “Will product liability litigation in footwear be the “next shoe to drop?””

NABOSO in  Ski Boots?

I have not yet had an opportunity to test NABOSO ski boots. But 2 racers I am working with are using NABOSO in zero drop minimal shoes. Stay tuned.

 

STANCE HACK: TUNE UP YOUR FEET

Biohacking Your Body with Barefoot Science

“…… hacking” or finding a way to more efficiently manipulate human biology.  This can include areas of sleep, nutrition, mental health, strength, recovery. (1)
– Dr. Emily Splichal – Evidence Based Fitness Academy

 

Last ski season, I developed some simple cues or hacks to help skiers and racers quickly find the body position and joint angles required to create the pressure under the outside foot with which to impulse load the outside ski and establish a platform on which to stand and balance on through the turn phase –  THE MECHANICS OF BALANCE ON THE OUTSIDE SKI: IMPULSE LOADING

The primary source of information that helped me develop these cues are the exercises developed by Dr. Emily Splichal. Her exercises also helped me to appreciate the extent to which traditional supportive footwear with raised heels and cushioned soles has damaged my feet and deadened the small nerves responsible for maintaining upright balance and the ability to initiate precise movement. Since implementing Dr. Splichal’s evidence based science, I am not only skiing at a level beyond what I considered possible, I am starting to walk naturally for the first time in my life.

The information contained in Dr. Splichal’s videos will challenge everything you know or thought you knew about what we have been conditioned to believe about our feet and the footwear we encase them in. Contrary to what we have been told, cushioning under the feet does not reduce impact forces on the lower limbs and protect them. Instead, it actually increases impact forces while slowing what Dr. Splichal refers to as the time to stabilization; the time required to stabilize, stiffen and maximally protect the joints of lower limb from impact damage – THE MECHANICS OF BALANCE ON THE OUTSIDE SKI: TIMING OF EDGE CHANGE

The Best Surfaces to Train On

A good place to start is to learn which surfaces are best to train on. Again, while it may seem logical and intuitive that surfaces with cushioning are best because they will protect the body from shocks, studies show the exact opposite to be true. Over time, support and cushioning in shoes can diminish the sensitivity of the rich small nerve matrix in the feet that acts as a neural mapping system for balance and movement. In her YouTube video, Best Surfaces to Train On (https://youtu.be/gvJjIi3h1Bs), Dr. Splichal discusses the effects of different surfaces on plantar small nerve proprioception and explains how barefoot training is a form of small nerve proprioceptive training designed to activate the plantar foot. Balance training is best done barefoot.

The Power of Plantar Proprioceptors

Watching Dr, Splichal’s webinar presentation Understanding Surface Science: The Power of Plantar Proprioceptors – https://youtu.be/t5AU-noqMFg will further your appreciation of the power of plantar proprioception.

First Stance Hack – Plantar Foot Release for Optimal Foot Function

Dr. Splichal’s 6 Minute Plantar Foot Release for Optimal Foot Function – https://youtu.be/zyrKgFwsppI will dramatically improve foot function.
Dr Splichal explains how to use RAD rollers (golf ball or other firm balls will also work) to optimize foot function by releasing tissues in the plantar foot by applying pressure to the 6 areas shown in the graphic below.
Dr. Splichal advises to focus on using a pin and hold technique  (not rolling the foot on the balls) to apply pressure to these 6 spots on each foot holding for about 20 seconds on each spot with each of the three different sized rounds for a total time of about 6 minutes. The foot release should be done 2 times and day and prior to each training session.
In my next post I will talk about the second Stance Hack: Pressing Down on the Big Toe to Impulse Load the Ski and Power the Turn

1.  https://barefootstrongblog.com/2017/04/28/biohacking-your-body-with-barefoot-training/

REVISIONS TO CORE CONCEPTS

Due to recent interest in CORE CONCEPTS on the HOME page menu (above), I have started to revise it. The current version appears below. Links to a number of pertinent papers and videos by Dr. Emily Splichal (Evidence Based Fitness Academy – EBFA ) have been appended to CORE CONCEPTS.


As bipeds, we propel our bodies forward by moving from one fascially tensioned base of support with foot to core sequencing on one foot to another fascially tensioned base of support with foot to core sequencing.

Skiing uses the same basic pattern. In skiing, we need to establish a fascially tensioned base of support with foot to core sequencing on one foot in order to be able to move with precision to another fascially tensioned base of support with foot to core sequencing on another foot. As far back as the 70’s, the famous French ski technician, Patrick Russell, said that the key to effective skiing is to ‘move from ski to ski’. What Russell was really alluding to is the process of alternating single limb support.

Ever since alpine skiing became formally established, it has been known that the best skiers move from the outside ski of one turn to the outside ski of the next turn. Although this may sound simple enough, the key to being able to effectively move from ski to ski (foot to foot) is the ability to establish a fascially tensioned base of support with foot to core sequencing one foot and then use it to move the body or Centre of Mass to the new outside foot (current uphill ski) of the next turn. Good skiers do this so seamlessly that turns seem to have no beginning or end. The turns just flow together. When viewed in the context of stance and swing phases, the resembles to walking becomes apparent,

How to make skiing as intuitive as walking is what this blog is about. I devoted an entire series of patent to this subject commencing with US Patent No. 5,265,350 and associated international patents on the elements of a minimal ski boot necessary to accommodate the process of establishing a fascially tensioned base of support with foot to core sequencing on one foot and transitioning seamlessly back and forth between bipedal and monopedal stances.

The ability to balance multi-plane torques on the outside leg of a turn is, and continues to be, the secret of the worlds’ best skiers including Toni Sailor, Nancy Greene Raine, Pirmin Zubriggen and, today, Mikaela Shiffrin, Lindsey Vonn and Ted Ligety to name but a few.


A REVIEW OF GAIT CYCLE AND ITS PARAMETERS – Ashutosh Kharb1, Vipin Saini2 , Y.K Jain3, Surender Dhiman4 – https://ijcem.org/papers72011/72011_14.pdf

Dynamic loading of the plantar aponeurosis in walking – Erdemir A1, Hamel AJFauth ARPiazza SJSharkey NA. – https://www.ncbi.nlm.nih.gov/pubmed/14996881

Active regulation of longitudinal arch compression and recoil during walking and running – Luke A. KellyGlen Lichtwark, and Andrew G. Cresswell – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4277100/

The Foots Arch and the Energetics of Human Locomotion – Sarah M. Stearne, Kirsty A. McDonald, Jacqueline A. Alderson, Ian North, Charles E. Oxnard & Jonas Rubenson – http://www.nature.com/articles/srep19403

Shoes alter the spring-like function of the human foot during running – Kelly LA1, Lichtwark GA2, Farris DJ2, Cresswell A2. – J R Soc Interface. 2016 Jun;13(119). pii: 20160174. doi: 10.1098/rsif.2016.0174. – https://www.ncbi.nlm.nih.gov/pubmed/27307512


The Science of the Human Lever: Internal Fascial Architecture of the Forefoot with Dr. Emily Splichal – https://www.youtube.com/watch?v=_35cQCoXp9U

SKIING: FEET FIRST

The processes of balance that configure the joints of the lower limbs originate in the feet in what is referred to as a bottom-up process.

The following text is excerpted from my US Patent No. 5,265,350 which was published in the major developed countries of the world on or about February 3, 1993. I have added emphasis with bold text to highlight key statements

The foot articulates in order to facilitate muscle function. Muscles respond in opposition to loads imposed upon the foot. A process ensues wherein the chain of articulations, initiated at the foot, are continuously mobilized so as to maintain a state of dynamic balance across the plantar-ground interface.

COMMENT: Structures of a ski boot that interfere with or otherwise impede the articulation of a joint or joints will reduce or even prevent a muscle or muscles from effectively contracting and shortening.

Bipedal function or bipedal stance, in the context of the invention disclosed, is defined as being a weight-bearing state wherein the feet are neither supinated (rolled outward) or pronated (rolled inward). This is described as a “neutral” state of the foot. It is usually associated with weight-bearing on two feet wherein each foot bears an equal proportion of the weight of the body.

Monopedal function or monopedal stance is defined as being the state achieved at the conclusion of a progressive weight transfer from two feet to the medial aspect of the plantar surface of one foot. As the weight transfer occurs, the foot to which the weight is being transferred undergoes pronation until a physiologic state of balance is achieved on one foot. Monopedal function distinguishes itself from other possible states of balance on one foot in that the ability to mobilize the joints of the body required to re-orient the centre of mass relative to the foot is possible while simultaneously maintaining a state of balance in relation to the forces acting on the user.

As an example, one can bear weight on one foot without having that foot pronate and, thus, not assume the position required for monopedal function, thus there is no significant inward movement of the ankle bone. This is done by shifting the weight to bear on the lateral aspect of the foot, and using the extrinsic leg and intrinsic foot musculature to support its medial arch. However, this form of balance produces a relatively static position in terms of ability to re-orient the centre of mass of the body relative to the supporting limb. This static quality is typical of states of balance on one foot achieved by other than monopedal function. With monopedal function, medial movement of the inside ankle bone is involved.

Monopedal function is a physiologic state wherein balance is achieved with the weight of the body borne on the medial plantar aspect of one foot. It has been recognized that the ability to balance on one foot (usually the one to the outside during a skiing or skating turn) is superior, in terms of balance and control, to balance on two feet, in sports such as skiing and skating wherein an instrument such as a ski or ice blade is affixed to the sole of the footwear. Monopedal function is extremely relevant in such applications for the following reasons:

(i) Balance on one foot, achieved through pronation, provides superior control of the articulations over balance on two feet. This translates to superior control of the ski or skate blade. It also translates into superior dynamic or kinetic balance. The mechanics of monopedal function permit the centre of mass of the body to be accurately placed and its relative position maintained, if necessary, with regard to the ski or skate blade affixed to the sole of the footwear.

(ii) A dominant position on the outside foot in the arc of a turn affords more efficient and precise control of the instrument since the inner limb, being relatively passive, is utilized primarily for the purpose of assisting balance.

(iii) The most important source of rotational power with which to apply torque to the footwear is the adductor/rotator muscle groups of the hip joint. In order to optimally link this capability to the footwear, there must be a mechanically stable and competent connection originating in the plantar processes of the foot and extending to the hip joint. Further, the balanced position of the skier’s centre of mass, relative to the ski edge, must be maintained during the application of both turning and edging forces applied to the ski. Monopedal function accommodates both these processes.

(iv) In skiing, the mechanics of monopedal function provide a down force acting predominantly through the ball of the foot (which is normally almost centred directly over the ski edge). In concert with transverse torque (pronation) arising from weight bearing on the medial aspect of the foot which torque is stabilized by the obligatory internal rotation of the tibia, the combination of these forces results in control of the edge angle of the ski purely as a result of achieving a position of monopedal stance on the outside foot of the turn.

(v) The edge angle can be either increased or decreased in monopedal function by increasing or decreasing the pressure made to bear on the medial aspect of the foot through the main contact points at the heel and ball of the foot via the mechanism of pronation. As medial pressure increases, horizontal torque (relative to the ski) increases through an obligatory increase in the intensity of internal rotation of the tibia. Thus, increasing medial pressure on the plantar aspect of the foot tends to render the edge-set more stable. The ski edge-set will not be lost until either the state of balance is broken or the skier relinquishes the state of monopedal function on the outside ski.

PROBLEMATIC FEET AND LEGS

In my post, THE IDEAL SKIER’S FOOT AND LEG, I described the characteristics that I observed over the years that were consistently associated with the feet and legs of the best skiers and racers. When I first started to see this pattern I didn’t understand why these characteristics were associated with superior technical ability. What I did come to understand very quickly was that skiers with feet and leg shapes that were less than ideal had difficulty skiing without major modifications to their ski boots. The images below compare the ideal foot and leg shape to foot and leg shapes that are increasingly problematic. The dashed line indicates the top of the sides of the cuff of the ski boot shell. The vertical hash marks compare the width of the cross-sectional area of the ideal leg at the top of the sides of the cuff to foot and leg shapes that progressively less than ideal.

Foot and leg types

 

As the cross-sectional area of the legs becomes increasingly larger, it becomes increasingly difficult to accommodate the leg within the confines of a boot cuff. In some cases, leg shapes make it difficult to even close the cuff buckles without extending the bales or re-locating the buckles. These types of fleshy legs are mostly associated with females although some males have the extreme shape depicted in the righthand image.  Females with wide hips tend to have tibias that are either straight or angle inward as shown in the sketch below. This can be a big problem if the cant angle of a boot cuff cannot be adjusted sufficiently to obtain a neutral cuff alignment with legs. Boots with no cuff adjustment, like the old Lange XLR, had cuffs that were canted outward 3 degrees. This meant that female racers with tibias that were straight or angled inward would be hard on their inside edges in events like downhill if they tried to relax and let their skis glide.

Female with wide hipsSome females have tibias that angle inward and fleshy legs. Since the rear spoiler of the boot cuff determines the angle of (dorsi) flexion of the ankle joint, skiers with large calves and tibias that are straight or angle inward have too much forward lean and the wrong cuff cant. When I worked with female racers in the late ’70s and early ’80s it typically took a lot of ingenuity and a lot of work to come up with a solution.

The problem with ski boots is that the shape of the lower part of the shell and the shape of the cuff are usually designed to interface with each other in a specific configuration. This limits the ability to align the cuff in a different position with the lower shell. It was Alan Trimble, the boot tech for Lange USA, who taught me how to make cuts in the shell bottom where it interfaced with cuff, position the cuff in the desired orientation then rivet the two pieces together. Lange was one of the few boots that allowed for this kind of modification.

When I worked with Langes I had a supply of boot parts with no holes drilled in the cuffs. This made it easier to assemble boots in non-stock configurations. The soft Lange fabric liners with fit pockets made it easy to remove padding that was interfering with ankle-leg movements. A common complaint was pressure on the inside ankle bone and even along the inner aspect of the foot below and in front of the ankle. I got very good at stretching the shell wall in this area. I even had special tools made for this purpose. From feedback from racers, I came to know that it was important to not have any pressure on the inner aspect of the ankle and the area around it. But it took me years to understand why. Here is a short video clip that shows the movement of the ankle and leg that is fundamental to the technique racers such as Ligety and Shiffrin use. In a future post I will explain why and how this works.