SR Stance Posts

WHY THE OPTIMAL STANCE FOR SKIING STARTS IN THE FEET

In this post, I am going to discuss why the optimal stance for skiing is dependent on the loading sequence of the new outside foot of turn, how this must start in the transition phase and why it is critical to the rocker impulse loading mechanism that engages the shovel and inside edge of the outside ski at edge change. This issue was introduced in THE MECHANICS OF BALANCE ON THE OUTSIDE SKI: TIMING OF EDGE CHANGE. The rocker impulse loading mechanism and the ability to balance on and control the outside ski is dependent on the ability to rapidly tension the biokinetic chain that stiffens the forefoot and torsionally stiffens the ankle and knee joints. This process enables top down, whole leg rotational force, into the turn, to be effectively applied to the foot and ski from the pelvis.

A Middle Ground on Stance

Although there is much discussion in skiing on the subject of stance, it is rare for discussions to include, let alone focus on, the foot.

The red rectangle in the graphic below shows the mid stance phase in the 8 component Gait Cycle.

A common position amongst the various authorities in skiing on stance, is that it is represented by the mid stance phase of the Gait Cycle. The 8 component Gait Cycle is the universal standard for discussion and analysis of gait in human movement. During the turn phase, the sole the outside foot or stance foot is in substantially constant contact with the zeppa or boot board. Since the ski stance does not involve initial heel contact or terminal phases, it was reasonable to conclude that skiing must be a mid stance activity.

Assuming that stance skiing is a mid stance activity also meant that the joints of the foot are mobile and the foot is still pronating and dissipating the shock of impact. The fact that the foot is not yet fully tensioned in mid stance, while still pronating, appears to have led to the conclusion that the foot is unstable and in need of support. Towards this end, form fitting footbeds, liners and, more recently, form-fitted shells were introduced and soon became standard. I described what has become known as the Holy Grail of skiing; a perfect fit of the boot with the foot and leg; one that completely immobilizes the joints of the foot in my post, A CINDERELLA STORY: THE ‘MYTH’ OF THE PERFECT FIT.  This objective, precipitated the premise that forces are best applied to the ski using the shaft of the ski boot as a handle with the leg acting as a lever. In this paradigm, the foot was relegated to a useless appendage.

The Missing Ninth Component – Late Stance

The problem with the assumption that mid stance is the defacto ski stance is that it has only recently been suggested that a critical ninth component, Late Stance, is missing from 8 components of the Gait Cycle.

Although it has been known for decades that the foot undergoes a sequential loading/tensioning process that transforms it from what has been described at initial contact as a loose sack of bones, into a rigid lever in terminal stance for propulsion, the effect of fascial tensioning on late stance has remained largely unexplored until recently when the exclusive focus on the rearfoot began to shift to the forefoot. I discuss this in BOOT-FITTING 101: THE ESSENTIALS – SHELL FIT.

As recently as 2004, Achilles/PA loading of the forefoot was poorly understood. Under Background, a 2004 study (2.) on the role of the plantar aponeurosis in transferring Achilles tendon loads to the forefoot states:

The plantar aponeurosis is known to be a major contributor to arch support, but its role in transferring Achilles tendon loads to the forefoot remains poorly understood.

The study found:

  • Plantar aponeurosis forces gradually increased during stance and peaked in late stance.
  • There was a good correlation between plantar aponeurosis tension and Achilles tendon force.
  • The plantar aponeurosis transmits large forces between the hindfoot and forefoot during the stance phase of gait.
  • The varying pattern of plantar aponeurosis force and its relationship to Achilles tendon force demonstrates the importance of analyzing the function of the plantar aponeurosis throughout the stance phase of the gait cycle rather than in a static standing position.

Changes in Muscle-tendon unit (MTU) and peak EMG increased significantly with increasing gait velocity for all muscles. This is the first in vivo evidence that the plantar intrinsic foot muscles function in parallel to the plantar aponeurosis, actively regulating the stiffness of the foot in response to the magnitude of forces encountered during locomotion. These muscles may therefore contribute to power absorption and generation at the foot, limit strain on the plantar aponeurosis and facilitate efficient foot to ground force transmission.

Transmits large forces and foot to ground force transmission means large downward forces directed at the ground or to a ski and from there to the snow.

Although I did not understand the esoteric details of fascial tensioning back in 1993, I was sufficiently aware of the relationship between peak tension in the plantar aponeurosis (PA), to be able to construct a simple model that illustrates how peak PA tension results in peak Achilles tension and how this causes the soleus muscle to go into isometric contraction, arresting further forward movement of the shank. I discuss this in detail in my series of posts on the SR Stance.

The photos below shows the simple model I made in 1993. Simple models of this nature are finding increasing use today to model what are called Anatomy Trains.

In late stance, the foot gets shorter in length and the arch gets higher and tighter as intrinsic tension transforms the foot from a mobile adapter in early stance into a rigid lever in late stance so it can apply the high force to the ground necessary for propulsion in the terminal stance phase that occurs at heel separation. The graphic below shows how the arch height h to foot length L ratio increases as the foot is getting shorter and the arch gets higher in late stance.

What has only recently being recognized is that the fascial tension that occurs in stance maximizes balance responses, neuromuscular efficiency and protection of the lower limbs through a process of  foot to core sequencing; one that stiffens the forefoot and torsionally stiffens the joints of the ankle and knee.

Loading/Fascial Tensioning Speed

A 2010 study (4.) found:

Early-stance tension in the PA increased with speed, whereas maximum tension during late stance did not seem to be significantly affected by walking speed. Although, on the one hand, these results give evidence for the existence of a pre-heel-strike, speed-dependent, arch-stiffening mechanism, on the other hand they suggest that augmentation of arch height in late stance is enhanced by higher forces exerted by the intrinsic muscles on the plantar aspect of the foot when walking at faster speeds.

…… or, by more rapid, forceful impulse loading at ski flat – see SUPER PETRA VLHOVA’S EXPLOSIVE IMPULSE LOADING IN ASPEN SLALOM

A 2013 study (3.) found:

Although often showing minimal activity in simple stance, the intrinsic foot muscles are more strongly recruited when additional loads are added to the participant.

A 2015 study (5.) found:

Changes in Muscle-tendon unit (MTU) and peak EMG increased significantly with increasing gait velocity for all muscles. This is the first in vivo evidence that the plantar intrinsic foot muscles function in parallel to the plantar aponeurosis, actively regulating the stiffness of the foot in response to the magnitude of forces encountered during locomotion.

These muscles may therefore contribute to power absorption and generation at the foot, limit strain on the plantar aponeurosis and facilitate efficient (vertical) foot to ground force transmission.

…….. or foot to ski to snow force transmission.

The Optimal Ski Stance is Unique

While the optimal stance for skiing has the greatest similarity to the late phase of stance, I am not aware of any stance that has requirements similar to the ski the stance where a specific loading sequence precedes rocker impulse loading as the outside ski changes edges in the top of a turn.

As with the gait cycle, the movement pattern associated with a turn cycle also involves loading and swing phases.

Time To Cascade

There are two intertwined rocker mechanisms that impulse load the forefoot at ski flat between edge change. These rocker mechanisms rely on what the 3 components of what I refer to as the Time To Cascade which is only possible when the plantar aponeurosis is rapidly fascially tensioned.

  1. Time to Fascial Tension which affects,
  2. Time to Stabilization which affects
  3. Time to Protection which protects the lower limbs 

In my next post, we will Meet the Rockers and continue with the discussion of the mechanics of balance on the outside ski.


  1. http://musculoskeletalkey.com/gait-and-gait-aids/
  2. Dynamic loading of the plantar aponeurosis in walking –Erdemir A1, Hamel AJFauth ARPiazza SJSharkey NA. J Bone Joint Surg Am. 2004 Mar;86-A(3):546-52.
  3. Dynamics of longitudinal arch support in relation to walking speed: contribution of the plantar aponeurosis – Paolo Caravaggi, Todd Pataky, Michael Gu¨ nther, Russell Savage and Robin Crompton – Human Anatomy and Cell Biology, School of Biomedical Sciences, University of Liverpool, Liverpool, UK – J. Anat. (2010) 217, pp254–261
  4. The foot core system: a new paradigm for understanding intrinsic foot muscle function – Patrick O McKeon1Jay Hertel2Dennis Bramble3Irene Davis4 Br J Sports Med doi:10.1136/bjsports-2013-092690
  5. Active regulation of longitudinal arch compression and recoil during walking and running Kelly LA, Lichtwark G, Cresswell AG – J R Soc Interface. 2015 Jan 6;12(102):20141076.

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)

IMG_1767

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

 

 

 

THE MECHANICS OF BALANCE ON THE OUTSIDE SKI: FIRST STEP

In this post, I am going to begin the first of what I expect to be a series of posts on the Two Step Process to Balance on the Outside Ski.

Prelude

Before I start, I am going to caution the reader that they should not expect that the ability to learn and engage the processes responsible for balance on the outside ski to be easy to understand or quick to learn.  Many obstacles stand in the way of the ability to balance on the outside ski. As Benno Nigg’s experiments in the early ’90s at the Human Performance Laboratory at the University of Calgary demonstrated, the human body is highly adaptable. If a person puts their feet in footwear that prevents natural barefoot function, the body will find a best case work around compromise.

This is what happens to skiers when they put their feet in ski boots. As the Polish study showed, over time, the body will adapt. But adaptation always comes at a price.  Some skiers may adapt to constraints of a ski boot to the point where they are considered expert skiers by the prevailing standards. But they typically reach a point where they can no longer advance. Given same ability, the least compromised skiers become the best.

The problem faced by skiers who wish to learn balance on their outside ski (foot) is that the ingrained motor patterns their brain has created as a work around to address the limitations caused by their ski boots can be exceedingly difficult to erase. A skier will typically make some progress only to have their brain revert to motor patterns that have worked in the past when it senses danger. When this happens, the odds are great that even the most athletically gifted skier may have to relearn skiing to some extent. I have seen many graphic examples of this pattern over the past several years in skiers and racers I have worked with.

WARNING: The Mechanics of Balance on the Outside Ski is Not Simple

About the simplest way I can describe the mechanics is that the First Step involves a heel to 1st MPJ rocker loading mechanism while and the Second Step involves an intertia-driven turntable, over-centre mechanism. The mechanics is unified sequence of events. The reason I have broken it two steps is to make it easy to understand the critical nature of the first part of the sequence.

More than 25 years ago, I tried to make the First Step simple and easy to understand with the model I fabricated shown in the photo below and that graphic illustration that follows that shows how the Achilles tendon tensions the Plantar Aponeurosis (aka the Plantar Fascia) and enables foot to pelvic core sequencing. Note the annotation in graphic to Late Stance and (SR) Ski Stance Zone.

In my demonsrations, I  would drop the model on a table from a height of a few inches.  The rotation of the leg of the model would be quickly arrested by simulated isometric contraction of the Achiles. The model and the demonstration failed to garner attention or interest because the importance of the forefoot to foot function was not on the radar screen. Instead, the focus was on the hindfoot and addressing the known looseness of the forefoot associated with the mid stance phase of gait. A late stance phase was not yet part of the gait cycle narrative. The importance of late stance and fascial tensioning of the forefoot to foot function and foot to core sequencing has only recently been recognized.

sr-tripod-demo

Plantar Apo Dynamics

First Step

The First Step is to tension the biokinetic chain that extends from the MPJs of the foot to the pelvis. The timing of this event, which is critical, will be discussed in a later post.

The key move is the loading of the outside foot. This should happen in the top of the turn as the fall line is approached. This is the point where a skier should become the tallest in relation to the snow. At the end of a turn (in the bottom) is where a skier should be lowest.

It is not possible to replicate the loading move except when skiing because of the dynamic nature of the 3-dimensional forces associated with ski maneuvers. But the forefoot loading move that creates fascial tension the forefoot is essentially the same move we make when we move forward on the stance foot in walking in preparation to take a step. Once the foot has adapted to the ground, forward rotation of the shank (ankle flexion) is arrested by isometric contraction of the calf muscle. At this point, further forward movement of the torso occurs through knee extension in what amounts to a heel to ball of the foot rocker mechanism; i.e. a forward and downward action that applies force to the ground to prime the energy return foot spring in preparation to propel the body forward.
One way to get a feel for this mechanism is to stand sideways across the bottom of a stair and place one foot on the first tread about a whole foot length ahead of the foot on the floor. The knee of the leg on the floor should have slight bend so the calf muscle is in isometric contraction (SR Stance). The angle of the shank of the foot on the tread should be a little less than 90 degrees in terms of dorsiflexion. From this base position, the torso is projected forward in order to achieve a position of balance over the foot on the first tread. This is roughly what the loading move should feel like in skiing that is made as the fall line is approached. Once a feel for this has been acquired I can discuss how this integrates with rotation of the leg.
It is important to not have the ankle flexed for the above exercise because the ski boot limits ankle flexion. At the start of the transition at the end of a turn, the weight will be under the heel of the inside (uphill) foot. It is also important that the calf muscle of the foot on the stair tread go into isometric contraction so that further forward movement of the torso occurs through knee extension.
In a ski turn, the forefoot loading move is one of a quick heel to 1st MPJ forward rocker knee extension pulse that loads the ball of the foot (1st MPJ). Loading of the 1st MPJ (ball of the foot) is caused by forward movement of the torso (CoM), not plantarflexion. This loading move is made in the top of a turn as the fall line (aka rise line) is approached. The window in which to make this move is narrow and the time required  to complete the move, brief.
If you watch video of Shiffrin slowed to 0.25 normal speed or step the video in frame-by-frame, you will clearly see her make this loading pulse which usually involves a lifting of the fore-body of the old outside ski due to swing leg reaction force.
In my next post, I will discuss Step Two.

 

 

 

 

 

 

 

 

 

 

 

WHY YOUNG TALENTED SKI RACERS FAIL AND EVENTUALLY QUIT RACING

The impetus for the subject of this post came from interest in my post FEATURE POST: MIKAELA SHIFFRIN: THE POWER OF SHEAR FORCE and an article (1.) in the  February 14, 2017 edition of Ski Racing by sports psychologist, Dr. Jim Taylor.

Taylor’s article, aimed at U14 and younger ski racers, points out that this is the age where the foundations are laid which often determine how well a racer does and especially how long they will remain in ski racing. Taylor cites statistics that show that qualifying for Topolino or the Whistler Cup (international competitions for 13-15 year olds) isn’t highly predictive of success even five years later. Specifically, only 25% of those who qualified for those race series later earned a spot on the USST. Moreover, 35% were off the elite ski racing radar within four years; some before their 18th birthday. The problem, that is the focus of Taylor’s article, is that parents enter what he calls the “too” zone, where the parents of kids, who are 11 years old or younger, have become “too” important to the parents who have become “too” invested in how their kids do (or don’t do).

The question I have is what events preceded parents getting to the “too” zone? I have seen more than one situation where a child who started ski racing at a very young age and who was considered to be a child ski racing prodigy, had a promising racing career unravel soon after reaching their teens. Why? What, changes happened that could have caused such a tectonic shift?

Let’s go back to beginning when a racer first showed promise. Many racers demonstrate prowess when they are only 4 or 5 years old. Often, one or both parents are elite skiers and one or both may have raced. In such a situation a young racer would have had an excellent role model that would have helped them  become comfortable by following one or both of their parents down the ski hill. But there are also other important factors in a young racer’s favour:

  • They are usually light weight.
  • They are usually short in stature.
  • Their muscles and skeleton are not yet fully developed.
  • Their feet are usually small.
  • They may lack fear.

A significant factor is that young racers often learn to ski in their mother’s ski boots or boots that would be considered too big for their feet if they were older. The implications? Young racers acquire a kinesthetic sense of how to stand in their boots in what I call the SR (stretch relfex) Stance (3. to 10.). As a consequence, they acquire dynamic stability that provides superior edge and ski control while enabling the myotatic stretch reflex balance response.

The authors of a Polish study on skier balance (2.) cite three types of postural reactions to external forces that disturb equilibrium and can cause the body to lose balance can be observed.

  1. The first reaction is the myotatic stretch reflex, which appears in response to changes in the position of the ankle joints, and is recorded in the triceps surae muscles. This is the earliest mechanism, which increases the activity of the muscles surrounding a joint that is subject to destabilization. Spinal  reflex triggered by the myotatic stretch reflex response causes the muscle to contract resulting in the stiffening of the surrounding joints as a response to the stimulus that has disturbed the balance. For example, changes in the angle of the joints of the lower limbs are followed by a reflexive (fascial) tensioning of adjacent muscles. The subsequent release of the reaction prevents excessive mobility of the joints and stabilises the posture once again.
  2. The next reflex in the process of balancing is the balance-correcting response, which is evoked in response to a strongly destabilising stimulus. This reactive response has a multi-muscle range, and occurs almost simultaneously in the muscles of the lower limbs, torso and neck, while the mechanisms that initiate the reaction are centrally coordinated.
  3. The last of the three types of muscular reaction is the balance-stabilising response. In a situation of a sudden loss of balance, a myotatic stretch reflex first occurs and is then is followed by a balance correcting response, which prevents or attempts to prevent a fall.

I call these balance responses green (postural reaction 1), orange (postural reaction 2) and red (postural reaction 3).

As young racers enter their teens, a number of significant changes have occurred.

  1. They are much heavier.
  2. They have grown in height
  3. Their muscles and skeleton are more developed.
  4. Their feet have grown larger and are more defined.

It is about this time in what is appearing to be a child’s promising racing career, that parents turn to the experts in a well intended effort to maximize their child’s chances of success. One of the key things parents often do is to get race boots for their child and have them customized with footbeds, form-fit liners and increasingly, heat molded shells. The process typically involves what is called race fit wherein ski boots are downsized to the smallest possible shell that the feet can be squeezed into. Custom footbeds or orthotics are considered an essential integral component of race fit because they prevent the foot from spreading and elongating. But this actually interferes with or even prevents the fascial tensioning process that enables dynamic stability and the myotatic reflex associated with the ultra high speed spinal reflex balance response (11).

No longer able to use the myotatic reflex (Green = Normal) balance response, the CNS shifts to Level 2 (Orange = Caution) or even Level 3 (Red = DANGER).

What happens next? The young racer starts to become intimidated by courses and conditions they were previously comfortable with. When this happens, their brain senses imminent danger of serious injury or worse and resorts to what I call the Survival Technique. Survival becomes the priority of the CNS at the expense of speed. Racers start losing ground to lesser racers. Not understanding the cause, parents and coaches can start pushing the child in an effort to get results. The more the child tries, the worse things get. When this happens, frustration sets in. Eventually, the child no longer wants to race. Defeated by their boots, the child eventually quits ski racing and takes up some other sport.

Unfortunately, this story is all “too” common. This is also one of the “toos”.


  1. What Young Ski Racers Need – http://www.drjimtaylor.com/4.0/young-ski-racers-need-dont-need/
  2. Influence of a nine-day alpine ski training programme on the postural stability of people with different levels of skills  (April 2016, Biomedical Human Kinetics (DOI: 10.1515/bhk-2016-0004) – Michał Staniszewski, Przemysław Zybko and  Ida Wiszomirska,  Józef Piłsudski University, Warsaw, Poland.
  3. THE SR STANCE: SURFACE EFFECTS,
  4. THE SR STANCE AND TOTAL BODY CORE INTEGRATION
  5. SR STANCE: ROUNDING THE BACK AND SHOULDERS
  6. THE SR STANCE: AFFECT OF JOINT ANGLES ON COM
  7. LEARN THE SR STANCE IN 3 EASY STEPS
  8. SR: ACHILLES-ARCH TENSION
  9. SR STANCE BASICS: ECCENTRIC MUSCLE POWER AND THE STRETCH REFLEX
  10. I-C-E: SR
  11. INNATE FLOW BALANCE

TRANSITIONING THE SR STANCE TO THE SKI BOOT

In this post, I will describe the sequence of events required to successfully transition the SR Stance learned barefoot out of the ski boot, into the ski boot.

Learning and rehearsing the SR Stance in bare feet on the same hard, flat surface provides a kinesthetic sense or reference with which to assess the effect of external influences. By following a specific sequence of events, the effects of individual components such as boot board (zeppa) surface and ramp angle, clearances of the foot to the inner shell wall, footbeds and liners can be identified.

A preliminary step is to measure the boot board (zeppa) and binding (delta) ramp angles. Although the effect of ramp angle on stance and skier balance should be studied in a laboratory setting and in actual ski maneuvers, through subjective assessment in working with skiers and racers, I have arrived at a range of 2.5 to 2.7 degrees of total ramp angle (zeppa + delta) that supports the SR Stance. A combination of approximately 0.2 degrees of delta in combination with 2.3 to 2.5 degrees of zeppa seems to give the best results. The window of the total ramp angle that supports an SR Stance appears to be narrow and falls off rapidly on either end of the range.

Steps to Transition the SR Stance to the ski boot

  1. In bare feet, learn and rehearse the SR Stance as described in my posts on the subject on 2 feet until the SR Stance is familiar. Try and maintain the spacing of your feet every time you rehearse the SR Stance.
  2. In bare feet, learn and rehearse the SR Stance as described in the posts on the subject on 1 foot until is familiar.
  3. Add a ramp board with the same combined zeppa + delta ramp angle as your ski boots and skis and repeat exercises 1 and 2.
  4. Try the same exercises above while wearing your ski socks. You might be surprised.
  5. Repeat the exercises 1, 2 and 3 with the insoles or footbeds (if you are using them) from your ski boots in place under your feet.
  6. Repeat exercises 1, 2 and 3 while standing in the liners from your ski boots with no insoles in them. Check for areas of tightness. Are your toes crunched up? Do the liners feel too short? Can you sense significant pressure around the ankle bones or on your Achilles? If yes to any of the preceding, flag the liner as a potential problem in terms of the ability to assume the SR Stance in your ski boots.
  7. Repeat the above exercise while standing in the liners with the insoles or footbeds (if you are using them) in place under your feet. If you feel significant pressure under the arches of your feet, flag the liner as a potential problem in terms the ability to assume the SR Stance in your ski boots.
  8. With your ski boots spaced approximately the same distance apart as your feet in exercises 1. and 3., stand in the ski boot shells (no liners). Try and assume the SR Stance. Check the shell wall for interference with structures of your feet such as ankle bones, width across the balls of your feet and the alignment of your big toe. The big toe should be able to sit straight, in its natural alignment.
  9. If there are no issues with the shell, insert the liners and repeat the above exercise.

If you have made it this far with no significant issues, congratulations. You are among the world’s elite skiers, the top guns, the best of the best. But the odds are overwhelming that most who try the above sequence of exercises will have identified more than one issue that prevented them from conforming to the SR Stance barefoot reference.

In my next post, I will discuss the types of modifications typically needed to remove the impediments to the SR Stance identified in the above series of exercises.


See posts on the SR STANCE under the drop down menu under the heading INDEX OF POSTS on the Home page.

 

 

THE SR STANCE: SURFACE EFFECTS

A good segue to continuing my discussion of the SR Stance is to provide a tool that will enable the assessment of the effect of different surface densities and textures and footwear, orthotics and generic insoles on the small nerve proprioceptors in the plantar foot.

Most people assume that cushioning under the plantar foot is a good thing; that it provides comfort and helps protect the foot from shocks. Who needs footbeds? Everyone. It’s only common sense. Everyone knows the foot is weak. It needs support. Except, that none of this is true.

“With thousands of plantar receptors, the foot is also a proprioceptive-rich structure, containing thousands of small nerves that are sensitive to every subtle movement we make. Our ability to walk, run or jump is all initiated through stimulation of these nerves on the bottom of the foot (aka the plantar foot).

“Because of the smaller diameter these plantar nerves are able to send signals faster to the Central Nervous System, creating faster response times”.

– Barefoot Strong by Dr. Emily Splichal

“80% of our plantar proprioceptors are sensitive to vibration”    – Nigg et al

“With small nerve receptors sensitive to stimuli such as texture, vibration, pressure and skin stretch, the skin on the bottom of the foot is unique when compared to the skin on the top of the foot or the lower leg.

“As soon as we put on socks, orthotics  or shoes we block these highly sensitive small nerves on the bottom of the foot.”

– Barefoot Strong by Dr. Emily Splichal

What Dr. Splichal says is true of any form of arch support. Ski boots are arguably the worst form of footwear for blocking the highly sensitive small nerves on the bottom of the foot.

As Dr. Splichal explains, the power of neuromuscular activation that enables precise balance and movement originates from the ground and moves upward through the plantar foot.

An easy way to impart an appreciation of how the stability, density and texture of surfaces under the plantar foot or structures such as insoles, orthotics, ski boots, liners or any form of footwear, affect stance, balance and movement patterns is by doing a series exercises on one foot starting barefoot on a hard level, stable surface, then adding different materials between the plantar foot and the supporting surface and assessing their effect on balance.

Dr. Splichal demonstrates a series of exercises in her EBFA YouTube Fitness group called Best Surfaces for Barefoot Training – https://youtu.be/gvJjIi3h1Bs

There are some issues with the quality of this particular video, especially as it ends and the volume increases dramatically. So use caution, especially if you are wearing earbuds or headphones. This issue aside, Dr. Splichal’s demonstration is spot on.

Reference Surface

The reference surface for establishing a baseline should be solid, stable, level and uniform. Texture is important. The worst surfaces for small nerve stimulation are smooth and glass like. Through experimentation, I have found that the best surface in my home is the concrete floor in the mechanical room which is coated with an epoxy paint with fine sand imbedded in it. The worst surface is the smooth laminate in the main living area. Tile in the entry hall with a slight texture is somewhere in between.

The photo below shows textured surface concrete on the left, smooth laminate on the right.

textures

Balancing on One Foot

Although balancing on one foot in a process of alternating single limb support is our basic mode of locomotion, most people seldom engage in prolonged balance on one foot. In order to ensure accurate assessment of surface effect, the move from balance on two feet to balance on one foot should be rehearsed. In my patents, I refer to these two states as bipedal and monopedal support.

Start by standing relaxed on both feet in an upright stance. Start moving the pelvis towards one foot. The movement of the pelvis should be in an arc that is sideways and forward as if the side of the pelvis on the support leg is moving diagonally towards the little toe.

As the pelvis moves forward, relax the ankle and allow the weight (pressure) to move to the ball of the foot. Keep a small bend in the knee as Dr. Splichal advises in her video.

Move back to balancing on two feet. Then repeat the balance exercise on the other side.

Repeat the exercise until you can quickly find stable balance on each foot and maintain it with minimal effort for at least 20 seconds. This may take time if the muscles that are being recruited are weak and/or unbalanced.

When you are comfortable balancing on either foot, try the exercise on different stable, hard surfaces and compare the effect of the different surface textures on balance.

You may want to try the same exercise on carpet if it is available.

A Word about Pronation

A campaign of misinformation has created a widespread perception that any amount of pronation is unnatural, even dangerous and should be prevented with a supportive insole or orthotic. Some experts have taken the position that a small amount of pronation is desirable but that it should be restricted to a specific amount controlled by an orthotic.

In a future post, I will expand on my earlier discussions of the 3 foot types. While it is correct that both pronation and supination are abnormal, the context of abnormal is in bipedal stance. From a perspective of basic trigonometry, the leg must adduct (move towards center of the body) about 6 to 7 degrees in order for the foot to be positioned under the centre of gravity. The foot must rotate an equivalent 6 to 7 degrees about its long axis in order for its tripod points to become compliant with the supporting surface.  STJ joint coupling produces an equivalent amount of internal rotation of the tibia about its vertical axis. Eversion/internal rotation is called pronation.

The absurdity of what amounts to an all out war on pronation should become apparent from viewing the stick man figure below from my patents.

FIG 23A - 23BSystematic efforts aimed at immobilizing the joints of the foot and leg in the ski boot, usually in neutral STJ, prevent skiers from assuming a balanced (read: pronated) position on the outside foot and ski ski thus ensuring the existence of an unbalanced moment of inversion/external rotation force. In addition, studies have shown that restraining the ankle in a tightly fitting ski boot increases laxity of the knee under closed chain whole leg rotation by approximately 30% over lesser forms of ankle constraint.

In my next post, I will discuss a series of exercises for assessing the effect of the components of the ski boot, including different liner components and interventions that support the arch of the foot.


Dr Emily Splichal is a Podiatrist and Human Movement Specialist.

She is the Founder of the Evidence Based Fitness Academy (EBFA) and Creator of the Barefoot Training Specialist, Barefoot Rehab Specialist and Bare Workout Certifications for health and wellness professionals.

Her book, Barefoot Strong is available in print and ebook formats.

http://evidencebasedfitnessacademy.com/faculty.html