Dr Emily Splichal

THE ZEPPA TIPPING POINT PROBLEM

A recent post on The Foot Collective FaceBook page titled Humans aren’t meant to walk on ramps!, highlighted the problems caused by elevating the heel above the forefoot known in the footwear industry as drop. Like the author of the post, I also wear zero drop shoes like Xero and Lems exclusively  (with NABOSO insoles) and spend all of my time indoors barefoot. Like the author, I too have experienced an immediate, unnatural and a sense of disorientation in terms of a connection with the ground, when I have worn dress shoes and winter boots with moderate drop.

While some amount of boot board ramp angle or zeppa appears to necessary for a strong, tensioned stance (what I refer to as a planted or rooted stance), the amount of zeppa is turning to be much less than I originally thought. It may be less than 1.5 degrees total (zeppa + delta). Assuming zero delta, there appears to be a very narrow range within which zeppa is optimal after which a tipping point is reached in terms of adverse effects on the motor control and balance systems.

It has also become apparent that some racers are tuning ski response by adjusting binding delta. Zeppa and delta each have a different effect on ski response especially edge control and the ability of a skier to resist the forces acting on them in the load phase of a turn. I will discuss issue this in a future post.


Humans aren’t meant to walk on ramps!

Powerful post by TFC Educator @optimize.physiotherapy
👣
Why do most shoes have a heel on them?
This really hit home the other day when I put on my winter boots (because it snows in November in Canada). Being someone who goes barefoot all day at work and at home (and wears zero drop shoes), it was a very unnatural feeling. It really threw my walking off, and I noticed the effects immediately. It changed the way I walked, stood, and made me use different muscles.
Humans are meant to have a flat base. No other animal wears mini ramps on their feet, but we do. The problem is that your body adapts to having a heel on, and it works different from a biomechanical perspective in any given movement pattern (the higher the heel, the worse the effect…but even most casual, running, and gym shoes have heels)


One thing it really does is affect your ankle/foot function. It has a huge effect on ankle ROM and tissue tension around the ankle. The problem is, when you wear a heel all day at work/at the gym/walking around, your tissues adaptively shorten and you don’t require as much ankle ROM. But then you take your shoes off and walk, go up your stairs, squat down to get things around the house etc. This is where people have issues. Not only at the foot/ankle but all the way upstream at other joints



Ankle ROM is incredibly important, and walking on a ramped surface all the time is incredibly unnatural. So do yourself a favour and spend less time in heeled footwear or get rid of it altogether


The Foot Collective is a group of Canadian physical therapists on a mission to help humans reclaim strong, functional and painfree feet through foot health education.

The Foot Collective are empowering people with the knowledge they need protect their feet from the dangers of modern footwear and the guidance to fix their own feet.

http://www.thefootcollective.com

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.naboostechnology.com

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

 

THE SHOCKING TRUTH ABOUT SKI BOOTS

In this post, I will expand on the content of The Shocking Truth About Power Straps (1.) which was by far the most popular post since I started this blog in 2013.

While the truth about what power straps can potentially do if improperly adjusted is shocking, the lack of support in principles of applied science for the basic premise that I describe as indiscriminate envelopment as the approach to achieving a fit of a ski boot with the foot and leg of the user with the objective of substantially immobilizing it’s joints with unknown consequences, is even more shocking. Little or no consideration appears to be given to the effects of indiscriminate envelopment on the balance and motor control systems of the skier.

What is done to the foot and (lower) leg can affect the entire body. In his post, Foot biomechanics is dead. Discuss (2.), Professor Chris Nester states:

The foot is not a compilation of interconnected mechanical components that respond precisely to the laws of mechanics. It is a complex matrix of at least 11 biological tissues (i.e. skin, fat, muscle, tendon, joint capsule, ligament, bone, cartilage, fascia, nerves, blood vessels….) that responds to external loads through the symbiotic relationship between the motor control system and tissue properties.

Professor Nester goes on to state:

I believe the integration of our current foot biomechanics knowledge with insights from motor control, neurophysiology and related domains (e.g. tissue biology) will drive advances in foot function more than pursuing a pure mechanics paradigm.

Professor Nester proposes that the term biomechanics be replaced with the term Neurobiomechanics. I concur.

How Does the Ski Boot Affect the Human Performance of the Skier?

The short answer is that when the structures of a ski boot indiscriminately envelop the structures of a foot and a portion of the leg (aka the Perfect Fit or the Holy Grail), no one knows. While it is essential that a ski boot create a secure connection of the foot of a skier with the ski, it should not achieve this connection at the expense of natural neuromuscular function, especially balance.

In 1980, when I was about to prepare a new pair of Lange race boots for Steve Podborski, I asked myself whether it was possible to obtain a secure connection of the foot with the ski without compromising natural neuromuscular function or, even better, was it possible to enhance natural neuromuscular function?

I took a significant step towards answering this question in 1980 when I designed and fabricated a device I called a Dorthotic. The Dorthotic supports the upper or dorsal aspect of the foot as opposed to supporting the plantar aspect (i.e. the arch). My theory that loading the top of the foot or dorsum with a force perpendicular to the transverse or medial-lateral plantar plane of the foot has positive benefits for motor control and balance has begun to be recognized. The Dorthotic enabled Steve Podborski to compete and win on the World Cup Downhill circuit mere months after reconstructive ACL surgery and to eventually win the World Cup Downhill title, a feat no non-European has repeated. US and international patents for the dorsal device were awarded to me (David MacPhail) in 1983.

The success of the Dorthotic gave me a start towards answering the question of whether a secure connection of the foot with a ski was possible without compromising natural neuromuscular function. But I knew that I needed to learn a lot more. I realized that finding the answers I was seeking and especially unraveling the secret that enables the world’s best skiers to stand and balance on their outside ski, would require a multi-disciplinary approach.

The Missing Factor in Skiing: A Multi-Disciplinary Approach

A significant influence that served as the impetus for the design of the Birdcage research vehicle and the on-snow studies, was the work of Dr. Benno Nigg. In 1981, Dr. Nigg accepted an invitation to move from ETH Zurich, where he was the director of the biomechanics laboratory, to the University of Calgary, where he founded and developed the Human Performance Laboratory (HPL), a multi-disciplinary Research Center that concentrated on the study of the human body and its locomotion.

The publication of the Shoe In Sport in English in 1988 served as a seque to introduce me to Nigg’s research at HPL. Studies done at HPL found that any interference with the function of the human foot, even a thin sock, extracts a price in terms of the adaptive process the human body has to undergo to deal with what is really an externally imposed disability.

The Effect of Footwear on the Neuromusculoskeletal System

There is an excellent discussion in a recent post on the Correct Toes blog (3.) on the impact of a narrow toe box, toe spring and elevated heel of traditional footwear on the human body. Elevating the heel in relation to the forefoot will predictably cause a realigment of the ankle-knee-pelvis joint system with a corresponding adjustment in the tension of the associated muscles with a global effect on the Neuromuscularskeletal System. This has been known for decades. Elevating the heel in relation to the forefoot, will cause the ankle joint to plantarflex (reduce dorsiflexion) in relation to the support surface under the foot in order to maintain COM within the limits of the base of support.

Ramp Angle Rules

Due to the unstructured nature of the indiscriminate envelopment characteristic of the fit of the majority of conventional ski boots, it is extremely difficult, if not impossible, to determine the effect of constraint of this nature on the Neuromusculoskeletal System. So I’ll focus on the one aspect of the ski boot that has consistent and profound implications on skier human performance, especially motor control and balance; boot board ramp angle or zeppa. Binding ramp angle or delta compounds any effect of zeppa. For the sake of simplicity we’ll assume zero delta.

Contrary to the widely help perception, raising the heel of a skier in a ski boot does not cause CoM to move forward. In fact, it usually has the exact opposite effect. It puts a skier in the back seat with the weight on their heels. Worse, it can disrupt the competence of the biokinetic chain that dynamically stabilizes and protects the joints of the lower limbs. Excessive heel elevation can render a skier static and cause the balance system to resort to using the back of the shaft as a security blanket.

As of this writing, I am unaware of any standard within the ski industry for zeppa. It appears to be all over the map with some boots having as much as 6.5 or more degrees. The default zeppa for the human foot on a hard, flat level surface, is zero.

Through subjective experiments in 1978, I arbitrarily determined that zeppas in excess 3° had a detrimental affect on skier balance. In 1991, zeppas of 2.3° and 2.5° were chosen for the large (US 8-12) and small (US 4-8) Birdcages based on an analysis of the effect of ramp angle on COM and neuromuscular activity. This range appears to work for a majority of recreational skiers. But recent tests with a dynamic ramp angle assessment device that I designed and fabricated is finding the stance of elite skiers optimizes at much lower zeppa angles, with some skiers below 1.5°. Interestingly, when NABOSO insoles are introduced for the assessment, zeppas decrease even further. With minimal training, most skiers are sensitive to dynamic changes in zeppa of 0.1 degrees.

Implications for the future of skiing

A tectonic shift is underway on a number of fronts (see A Revolution) that is challenging the mechanical and static premises that form the underpinnings of the key positions in ski teaching and the design of equipment such as ski boots and the fit process. In my next post I will post recent material by Dr. Emily Splichal, functional podiatrist and inventor the revolutionary NABOSO small proprioceptive stimulating insole.


  1. https://wp.me/p3vZhu-UB
  2. https://talkingfeet.online/2018/01/18/question-3-foot-biomechanics-is-dead-discuss/
  3. https://www.correcttoes.com/foot-help/footwears-impact-musculoskeletal-system/

HIRSCHER AND SHIFFRIN WIN BY CROSSING THE LINE

When a World Cup racer wins a GS by a commanding margin, it’s a sure sign they’ve crossed the line and the gravity of the situation is significant. But I’m not talking about  breaking any rules. Instead, I’m referring to Hirscher and Shiffrin mobilizing the force of gravity by jumping across the rise line above the gate and/or minimizing pressure while rotating their skis across the rise line towards the gate so the edges of their outside ski progressively engage and lock up as they extend and incline closing the kinetic chain. Knee extension, in combination with ankle extension, uses the momentum of COM in conjunction with the force of gravity to progressively engage and apply force to the outside ski.

Reilly McGlashan has an excellent YouTube analysis of Marcel Hirscher using this technique in the 2017 Alta Badia GS (1.) The technique Hirscher and now Mikaela Shiffrin are using relates directly to the second rocker/internal rotation, impulse loading mechanism I described in a series of posts. The text below is excerpted from a comment I posted on McGlashan’s YouTube video analysis of Hirscher.

Hirscher progressively engages his edges, especially on his outside ski then hooks a tight arc close to the gate to establish his line. Once he has established his line, he no longer needs his outside ski. He gets off it in milliseconds and uses the rebound energy to project forward with only enough pressure on his uphill (new outside) ski to influence his trajectory of inertia so his COM enters the rise line at a low angle of intersection. He gets rebound energy from the loading  of his outside ski and from what amounts to a plyometric release of muscle tension from the biokinetic chain of muscles extending from the balls of his outside foot to his pelvis. The energy is created by the vertical drop from above the gate to below the gate similar to jumping off a box, landing and then making a plyometric rebound. Hirscher is skiing the optimal way and it shows on the clock and leader board.

Replicating the mechanism in a static environment is not possible because there is no inertia. But a device I have designed and constructed enables the mechanism to be rehearsed with the same feeling as in skiing.

The key is loading the forebody of the outside ski with a shovel down position as the leg is rotating the ski into the turn. This sets up the second rocker impulse loading mechanism that tips the ski onto its inside edge. Extending the knee and ankle uses momentum to exert a force on the snow with the ski.

The photo below shows the training mechanism head on. The white horizontal arms represent the sidecut of the ski. The platform under the foot can be adjusted transversely to change the sensitivity. Vertical plates set beside the ball of the foot and on the outer corner and behind the heel transfer turntable rotation torque to the ski created by rotating the leg internally with the glutes. The platform will only tilt under impulse loading if the second rocker can engage. Few skiers can use this mechanism because their ski boots do not accommodate second rocker biomechanics.

The link below is to a video that shows the effect of extending the knee and ankle while moving the hips forward and over the support foot (monopedal function). The stack height and minimum profile width of are FIS 93 mm/63 mm. Rotation in itself will not cause the device to tip onto its inside edge if centre of pressure is on the anatomic centre of the foot (through the centre of the heel and ball of the second toe).

Dr. Emily Splichal’s recent webinar on the Science of Sensory Sequencing and Afferent Stimulation (2.) is relevant to motor control and cognitive development associated with high performance skiing. Pay careful attention to Dr. Splichal’s discussion of the role of mechanoceptors and the fact there are none on the inner (medial) aspect of the arches of the feet which is why footbeds or anything that impinges on the inner arch is a bad thing. I will discuss the implications of Dr. Splichal’s webinar in a future post.

In my next post, I will provide detailed information on the training device.


  1. https://youtu.be/OxqEp7LS_24
  2. https://www.youtube.com/watch?v=2qPnrQ85uec&feature=youtu.be

 

 

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.

 

THE MECHANICS OF BALANCE ON THE OUTSIDE SKI: TIMING OF EDGE CHANGE

In my US Patent 5,265,350 (November 30, 1993), I stressed the importance of avoiding any structures in the ski boot that would delay or especially prevent, the loading sequence that enables a skier to rapidly assume a position of balance in monopedal stance on the outside ski at ski flat that occurs between edge change. The 2 paragraphs of text below are excerpted from the patent.

The avoidance of any obstruction (in the ski boot) is required in order to ensure that a monopedal stance will be attained without interference or delay. Such interference would be deleterious to the user and is, therefore, undesirable.

In order for the user to enjoy maximum control of the ski, it is important that these forces be transferred as directly as possible and without delay. As previously stated, this is an object of the invention. It is also important that forces exerted by the ski on rigid base 2100 be transferred as directly as possible and without delay to the foot of the user so that appropriate muscle action can be accurately and quickly stimulated which would act to make corrections which influence the relative position of the joints in order to maintain the user’s state of balance.

What I was really referring to is what Dr. Emily Splichal describes as Time to Stabilization.

The window for stabilization for optimal loading and energy transfer is very narrow and occurs as a skier approaches the fall or rise line at the point where a turn will start. The graphic below shows the Stabilization Zone for optimal loading and energy transfer to the outside ski shown circled in pink.

The timing of impulse loading is critical. The loading impulse is applied by a short, rapid knee extension made just as the ski is about to go flat on the snow between edge change in combination with forward movement of CoM in relation to the outside foot. Extending the knee tensions the hamstrings and gastrocnemius. This will cause the ankle extend slightly creating rocker-action impulse loading of the forefoot, especially the 1st MPJ or ball of the foot.

Dr. Splichal has graciously given me permission to republish her recent post. This may well be one of the most important articles ever written pertaining to skiing and ski technique.


 Time To Stabilization & Athlete Injury Risk

by Dr Emily Splichal – Evidence Based Fitness Academy

A majority of my podiatry practice is built around treating athletes and chronic athletic injuries.   From professional dancers to marathon runners all athletes – regardless of sport or art – require the same thing – rapid stabilization for optimal loading and energy transfer.  

dancer

Why is rapid stabilization so important? 

During dynamic movement such as walking, running or jumping (or skiing – my addition), the ability to rapidly load and unload impact forces requires a baseline of stabilization.   With a rate of impact forces coming in at < 50 ms during walking and < 20 ms during running it is no wonder the rate of stabilization must be fast!

To put this a little bit more in perspective.   Our fast twitch muscle fibers don’t reach their  peak contraction till about 50 – 70ms.   So if impact is coming in at rate < 20 ms during running and your hip / knee / ankle and foot are not already stable before you strike the ground – it is too late!     It physiologically is not possible to react to impact and stabilize fast enough.

A client or athlete who is reacting to impact forces will often present with ITB syndrome, runner’s knee, peroneal tendinitis, stress fractures, shin splints – and that’s just naming a few!

Considering Time to Stabilization (TTS)

In my workshops I often say that “we are only as strong as we are stable” or that “stability is the foundation through which strength, force and energy is generated or transferred”.

acle

The precision, accuracy and anticipation of stabilization must be so well programmed into the nervous system that peak stability is happening before contact with the ground.   This is referred to pre-activation and is associated with a faster TTS.

The opposite of pre-activation stabilization is reactive stabilization and is how many – if not most – of my patients or people in general are moving.   When we think of the rate of neuromuscular coordination even a small delay (think milliseconds) will result in tonic (exaggerated) muscle contractions, micro-instability and inefficient loading responses eventually leading to neuromuscular and connective tissue fatigue and injury.

So how can you improve client and athlete TTS?

1. Pre-activate base to center stabilization pathways aka foot to core sequencing

This is THE basis to EBFA Certifications Barefoot Training Specialist and BarefootRx.   With our feet as our base, the activation and engagement of our feet to the ground is key to center or core stabilization.    Fascially, the feet and core are connected through the Deep Front Line and must be integrated and sequenced as part of a proper warm-up or movement prep.

To learn more about foot to core sequencing please view HERE

2. Consider surface science to optimize foot feedback

All surfaces are designed differently with certain surfaces actually blocking and damping the critical proprioceptive input between foot and ground.    When we think of softer surfaces and mats, research has shown a direct correlation between softer surfaces and delayed / prolonged loading responses.

IMG_1753

Harder surfaces.  Surfaces that allow the transmission of vibration.  And surfaces with textures allow more accurate and precise proprioceptive input.   Thus led to the innovation of Naboso Technology by EBFA Founder Dr Emily Splichal

Ideally if Step 1 – pre-activation of our stabilization pathway could be done on a Naboso surface this would be ideal.    More information can be found at www.nabosotechnology.com

3. Footwear to allows optimal feedback and foot function

If we follow Steps 1 & 2  and activate the neuromuscular system barefoot and from the ground up we then want to ensure this carries over as soon as we put on our shoes (or ski boots – my addition) and begin our sport or activity.

Imagine if you activate the proper neuro pathways but then put your client into a thick cushioned shoe (or ski boots – my addition).  This essentially shuts off and defeats the purpose of Step 1 & 2.   We need to ensure a proper shoe is worn to allow this carry over into sport.    So think flexible, minimal cushioning. possible textured insoles (check out Naboso Insoles launching Spring 2017)

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The textured insole in the shoe above is NABOSO technology.


Dr. Emily Splichal, Podiatrist and Human Movement Specialist, is the Founder of the Evidence Based Fitness Academy and Creator of the Barefoot Training Specialist®, BarefootRx® and BARE® Workout Certifications for health and wellness professionals. With over 15 years in the fitness industry, Dr Splichal has dedicated her medical career towards studying postural alignment and human movement as it relates to foot function and barefoot training.

Dr Splichal actively sees patients out of her office in Manhattan, NY with a specialty in sports medicine, biomechanics and forefoot surgery. Dr Splichal takes great pride in approaching all patients through a functional approach with the integration of full biomechanical assessments and movement screens.

Dr Splichal is actively involved in barefoot training research and barefoot education as it relates to athletic performance, injury prevention and movement longevity. Dr Splichal has presented her research and barefoot education both nationally and internationally, with her Barefoot Training Specialist® Program in over 28 countries worldwide and translated into 9 languages.

Due to her unique background Dr Splichal is able to serve as a Consultant for some of the top fitness, footwear and orthotic companies including NIKE Innovations, Trigger Point Performance Therapy, Aetrex Worldwide, Crunch Fitness and Sols.

Degrees/Certifications: Doctor of Podiatric Medicine (DPM), Master’s Human Movement (MS), NASM-CES, NASM-PES, NSCA-CPT