EBFA

THE ORIGINS OF KNEE ANGULATION

A recent post on the Foot Collective Facebook page titled, Are you stable on 1 leg?, advises that if  you stand on one leg and look like the top row of pictures in the graphic below (red X), you have a foot & hip that are dysfunctional. This test is best done barefoot on a hard, flat, level surface.

Graphic with permission of Correct Toes

The lower photo (green checkmark) shows the alignment of a leg that is torsionally balanced (stiffened) in the ankle and knee joints. The foot and knee cap align straight ahead and square with the pelvis while the alignment of the knee with the foot, leg and thigh is substantially linear. If you can move to single limb support from two feet, easily achieve this alignment with minimal effort, sustain it for 30 seconds or more, and achieve similar alignment on both left and right legs, you probably have good stability in single limb support.

If you look like the upper photo (red x), it indicates dysfunction and especially a lack of torsional stability in the support limb. The problem is usually caused by constrictive, supportive, cushioned footwear and/or arch supports that, over time, deform feet and weaken the arches. Ski boots are one of the worst offenders in this regard.

If you and when you can achieve good stability in single limb support, you are ready to test the effect of footwear, especially your ski boots. Start by putting on your day to day footwear. Then do the same test on the same surface with each pair of shoes. Work your way up to your ski boots. Adjust the closures of your ski boots to the tension you normally set for skiing. If you are not able to quickly and easily assume the stable position shown in the lower photo (green checkmark), then you know that cause  is the footwear. You can then test the effects of insoles, including ski boot footbeds by removing them from the footwear, placing them on the test surface and moving to single leg support. While not perfect, these tests will help determine the cause of single support limb instability.

In skiing, an unstable outside support leg is characteristics of most skiers and even racers at the World Cup level. It is typically caused by ski boots interfering with the physiological processes that fascially tension the arches and forefoot that create the triplanar torsional stability of the ankle and knee joints of the biokinetic chain necessary to set up a platform under the outside ski to stand and balance on. But instead of addressing the underlying cause, the ski industry invented the term, knee angulation. Knee angulation is indicative of unbalanced torques acting about the uphill edges of the skis, especially the outside ski. When unbalanced torques are present about the edges of a skis or skis, unbalanced torques will also be present across the joints of the lower limb; not a good thing.

The alignment of the knee illustrated in the lower image (green checkmark) is seem as skier or racer enters the fall or rise line with outside leg extended, confirms the existence of a platform under the outside foot on which the skier or racer is balancing on with dynamic balance of torques across the joints of the ankle foot complex and knee. See my post MIKAELA SHIFFRIN AND THE SIDECUT FACTOR – http://wp.me/p3vZhu-1Uu

There is an abundance of information on programs to correct foot deformities,  muscle weakness and imbalances on web sites, YouTube and FaceBook groups such as The Foot Collective, Correct Toes, Feet Freex and the Evidence Based Fitness Academy – EBFA (Dr. Emily Splichal).

The Foot Collective web site has a series of posts on An Introduction to Feet and Footwear (1.) as well as a series of Foot-Casts (2.)

Meantime, a post on a web site called Rewire Me (3.) has an interview with Dr. Emily Splichal called No Shoes Allowed in which she discusses the importance of sensory information entering the body and the need to be able to process this information and handle the load and impact. Dr. Splichal suggests starting the process by getting the body and foot accustomed to sensory information without shoes acting as a barrier.

An excellent free paper with great graphics is The foot core system: a new paradigm for understanding intrinsic foot muscle function (4.)


  1. http://www.thefootcollective.com/an-introduction-to-feet-and-footwear/
  2. http://www.thefootcollective.com/footcast/
  3. https://www.rewireme.com/roses-blog/shoes-allowed/
  4. http://bjsm.bmj.com/content/49/5/290.full#xref-ref-39-1

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