If you are a sprinter, how you load the forefoot bipod might be a variable for speed or injury. Tendons can change their cross sectional area, if you load them.

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Of course this article is not exclusive for sprinters, it pertains to any running sport, even endurance.

Maximum isometric force had increased by 49% and tendon CSA by 17% !
Tendons can change their cross sectional area, if you load them.

Here I show lateral forefoot loading in a heel raise, and a medial forefoot loading in heel raise. This has to be part of the discovery process outlined below. Forefoot types will play into the loading choice, and unequal strength of the medial or lateral calf compartment will also play into the loading choice made. Where do you need to put your strength ? And is the forefoot competent to take that loading challenge ? Meaning, do they have a forefoot valgus? A forefoot supinatus ? These things matter. If you are a sprinter, how you load the forefoot bipod might be a variable of foot type, asymmetrical posterior compartment strength, or foot strike pattern in the frontal plane (search our blog for cross over gait and glute medius targeting strategies for step width) ,or a combination of several or all of the above. These things matter, and why and where you put your strength matters, if you are even aware of where and how you are putting the loads, and why of course. Of course, then there are people like the recent Outside online article that says how you foot strike doesn’t matter, but it does matter. But of course, if you do not know the things we have just mentioned, it is easy to write such an article.

Isometrics are useful, they have their place. In a recent podcast we discussed the place and time to use isometrics, isotonics, eccentrics and concentrics.
One of the goals in a tendinopathy is to restore the tendon stiffness. Isometrics are a safe way to load the muscle tendon complex without engaging a movement that might have to go through a painful arc of movement. With isometrics here is neurologic overspill into the painful arc without having to actually go there.
The key seems to be load. More load seems to get most people further along. Remember, the tendon is often problematic because it is inflammed and cannot provide a stiffness across its expanse. Heavy isometric loading seems to be a huge key for most cases. But, we have to say it here, not everyone fits this mold. Some tendons, in some people, will respond better to eccentrics, and strangely enough, some cases like stretching (perhaps because this is a subset of an eccentric it seems or because there is a range of motion issue in the joint that is a subset of the problem). Now the literature suggests that stretching is foolish, but each case is unique all in its own way, and finding what works for a client is their medicine, regardless of what the literature and research says.
Finding the right load for a given tendon and a right frequency of loading and duraction of loading is also case by case specific. Part of finding the right loading position is a discovery process as well, as noted in the photos above. Finding the fascicles you want to load, and the ones you do not want to load (painful) can be a challenging discovery process for you and your client. Finding the right slice of the pie to load, and the ones not to load takes experimentation. When it is the achilles complex, finding the safe However, if one is looking for a rough template to build from, brief, often, heavy painfree loads is a good template recipe to start with.

Here, in this Geremia et al article, "ultrasound was used to determine Achilles tendon cross-sectional area (CSA), length and elongation as a function of plantar flexion torque during voluntary plantar flexion."
They discovered that, "At the end of the training program, maximum isometric force had increased by 49% and tendon CSA by 17%, but tendon length, maximal tendon elongation and maximal strain were unchanged. Hence, tendon stiffness had increased by 82%, and so had Young’s modulus, by 86%.

Effects of high loading by eccentric triceps surae training on Achilles tendon properties in humans. Jeam Marcel Geremia, Bruno Manfredini Baroni, Maarten Frank Bobbert, Rodrigo Rico Bini, Fabio Juner Lanferdini, Marco Aurélio Vaz
European Journal of Applied Physiology
August 2018, Volume 118, Issue 8, pp 1725–1736

Podcast 123: The Rear foot: Understanding your RearFoot type

Key tag words:
foot types, rearfoot, forefoot, pronation, supination, shoe fit, forefoot varus, forefoot supinatus, rearfoot inversion, ankle rocker, injuries, rehab, corrective exercises

Rearfoot varus and Rearfoot valgus. Knowing the anatomy of your rear foot and its anatomic and functional posturing can lead to many problems in anyone. If you do not know the rearfoot type and posturing, you will not understand the rest of the foot mechanics. Without this knowledge, you will not know the reason for midfoot or forefoot problems, not understand what shoe you are in, or even why the shoe, footbed, orthotic you have chosen is either not fixing your problems, or causing them.  Join us on a journey down the rearfoot rabbit hole over the next hour.  Plus a few funny stories to lighten the biomechanics-heavy dialogue.
 

Show links:
http://traffic.libsyn.com/thegaitguys/pod_123final_cut.mp3

http://thegaitguys.libsyn.com/podcast-123-the-rear-foot-understanding-your-rearfoot-type

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That is our website, and it is all you need to remember. Everything you want, need and wish for is right there on the site.
Interested in our stuff ? Want to buy some of our lectures or our National Shoe Fit program? Click here (thegaitguys.com or thegaitguys.tumblr.com) and you will come to our websites. In the tabs, you will find tabs for STORE, SEMINARS, BOOK etc. We also lecture every 3rd Wednesday of the month on onlineCE.com. We have an extensive catalogued library of our courses there, you can take them any time for a nominal fee (~$20).
 
Our podcast is on iTunes, Soundcloud, and just about every other podcast harbor site, just google "the gait guys podcast", you will find us.
 
Show Notes:

https://www.ncbi.nlm.nih.gov/pubmed/27134364

https://www.ncbi.nlm.nih.gov/pubmed/25364132

RearFoot positions:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3588658/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3990938/

Powers CM, Maffucci R, Hampton S. Rearfoot posture in subjects with patellofemoral pain. J Orthop Sports Phys Ther. 1995 Oct;22(4):155-60.

Power V, Clifford AM. The Effects of Rearfoot Position on Lower Limb Kinematics during Bilateral Squatting in Asymptomatic Individuals with a Pronated Foot Type. J Hum Kinet. 2012 Mar;31:5-15. doi: 10.2478/v10078-012-0001-0. Epub 2012 Apr 3.

Shultz SP, Song J, Kraszewski AP, Hafer JF, Rao S, Backus , Mootanah R, Hillstrom HJ. An Investigation of Structure, Flexibility and Function Variables that Discriminate Asymptomatic Foot Types. J Appl Biomech. 2016 Dec 19:1-25. [Epub ahead of print]

 

Forefoot valgus: A fixed structural defect in which the plantar aspect of the forefoot is everted on the frontal plane relative to the plantar aspect of the rearfoot; the calcaneum is vertical, the mid tarsal joints are locked and fully pronatedWant…

Forefoot valgus: A fixed structural defect in which the plantar aspect of the forefoot is everted on the frontal plane relative to the plantar aspect of the rearfoot; the calcaneum is vertical, the mid tarsal joints are locked and fully pronated

Want to know more? Join us Wednesday evening: 5 PST, 6 MST, 7 CST, 8 EST for Biomechanics 309: Focus on the forefoot on onlinece.com.

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

Forefoot Varus or Forefoot Supinatus?Forefoot varus is a fixed, frontal plane deformity where the forefoot is inverted with respect to the rearfoot. Forefoot varus is normal in early childhood, but should not persist past 6 years of age (i.e. when d…

Forefoot Varus or Forefoot Supinatus?

Forefoot varus is a fixed, frontal plane deformity where the forefoot is inverted with respect to the rearfoot. Forefoot varus is normal in early childhood, but should not persist past 6 years of age (i.e. when developmental valgus rotation of forefoot on rearfoot is complete, and plantar aspects of fore- and rearfoot become parallel to, and on same plane as, one another (1)

Forefoot supinatus is the supination of the forefoot that develops with adult acquired flatfoot deformity. This is an acquired soft tissue adaptation in which the forefoot is inverted on the rearfoot. Forefoot supinatus is a reducible deformity. Forefoot supinatus can mimic, and often be mistaken for, a forefoot varus. (2)

A forefoot varus differs from forefoot supinatus in that a forefoot varus is a congenital osseous where a forefoot supinatus is acquired and develops because of subtalar joint pronation.

“Interestingly, only internal rotation of the hip was increased in subjects with FV – no differences were present in hip adduction and knee abduction between subjects with and without FV. The authors nevertheless conclude that FV causes significant changes in mechanics of proximal segments in the lower extremity and speculate that during high-speed weight-bearing tasks such as running, the effects of FV on proximal segments in the kinetic chain might be more pronounced.”

We wonder if the folks in this study had a true forefoot varus, or actually a forefoot supinatus (3).


The Gait Guys


1. Illustrated Dictionary of Podiatry and Foot Science by Jean Mooney © 2009 Elsevier Limited.

2. Evans EL1, Catanzariti AR2. Forefoot supinatus.
Clin Podiatr Med Surg. 2014 Jul;31(3):405-13. doi: 10.1016/j.cpm.2014.03.009.

3. Scattone Silva R1, Maciel CD2, Serrão FV3. The effects of forefoot varus on hip and knee kinematics during single-leg squat. Man Ther. 2015 Feb;20(1):79-83. doi: 10.1016/j.math.2014.07.001. Epub 2014 Jul 12.

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Did you see this in our recent blog post here ? a reader made us look closer. Did you catch it ?
The clients right foot appears to have a dropped 1st met head. (we hate this term, because it is not accurate and is a sloppy clinical description). In this still photo it appears plantarflexed.  But in this video, consider the descended 1st met head as due to the disuse or weakness of the EHL muscle (extensor hallucis longus) of the 1st toe. Or, is this in fact a compensated forefoot varus ? Sure looks like it. But with all that anterior compartment weakness (as we discussed in the previous blog post link above) it could just be a mirage. In the photo above, in a normal foot the rearfoot plane (greenline) should parallel the forefoot line (orange line). In this case, in this actively postured foot (thus some inaccuracy here, we are merely making a teaching point from the photo) the upslope of the orange line suggests a forefoot varus. This would be true if the first Metatarsal head also was on this line, but you can see that it has its own idea. This represents, in theory (regarding this photo), a compensated forefoot varus. But remember, this client is  holding the foot actively in this posture. A true hands on assessment is needed to truly define a Forefoot varus, and whether it is anatomic, flexible, rigid or in many cases, just a learned functional posturing from weakness of the flexor/extensor pairing of the 1st metatarsal complex or from other weaknesses of the other forefoot evertors.  It gets complicated as you can see.

As always, knowledge of the anatomy and functional anatomy allows for observation, and observation leads to understanding, which leads to answers and then remedy implementation. Our thoughts, knowing the case, is that this is a functional appearance illusion of a compensated forefoot varus due to the EHL, EDL and tibialis anterior weakness (anterior compartment) and how they play together with the flexors. One must be sure to assess the EHL when examining the foot. Test all of the muscles one by one.  We have been talking about toe extensors for a long time, they can be a paramount steering wheel for the forefoot and arch posture. Podcast 71 talks about this Forefoot varus, and you should care.
In a 2009 study by Reynard et al they concluded: 

  • “The activity of extensor digitorum longus muscle during the swing phase of gait is important to balance the foot in the frontal plane. The activation of that muscle should be included in rehabilitation programs.” (1)

here is the video again.

Have a burning desire to learn more about forefoot varus, here are 25 blog post links from our last few years. And/or you can take our National Shoe Fit program (downloadable links below).

Knowing what you are seeing during your exam and gait analysis can only truly come from coupling your observations with a clinical exam.  Anything less is speculation and guess work.  It is gambling, and this is not Vegas baby, this is someone’s health.

Shawn and Ivo, The Gait Guys

________________

National Shoe Fit Certification Program:

Gait Guys online /download store (National Shoe Fit Certification and more !) :

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1. Foot (Edinb). 2009 Jun;19(2):69-74. Epub 2008 Dec 31. Foot varus in stroke patients: muscular activity of extensor digitorum longus during the swing phase of gait.  Reynard F, Dériaz O, Bergeau J.

Other web based Gait Guys lectures:

www.onlinece.com   type in Dr. Waerlop or Dr. Allen,  ”Biomechanics”Reference

Podcast 71: Forefoot Varus, Big Toe Problems & Charlie Horses"

*Show sponsor: www.newbalancechicago.com

Lems Shoes.  www.lemsshoes.comMention GAIT15 at check out for a 15% discount through August 31st, 2014.

A. Link to our server: 

Direct Download: 

http://traffic.libsyn.com/thegaitguys/pod_72final.mp3

Permalink: http://thegaitguys.libsyn.com/podcast-71

B. iTunes link:

https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

C. Gait Guys online /download store (National Shoe Fit Certification and more !) :

http://store.payloadz.com/results/results.aspx?m=80204

D. other web based Gait Guys lectures:

www.onlinece.com   type in Dr. Waerlop or Dr. Allen,  ”Biomechanics”

______________

Today’s Show notes:

1. American College of Cardiology. Running out your healthy heart. How much exercise is too much ?

Running for 7 minutes a day cuts risk of death by 30%, study says
http://wgntv.com/2014/07/29/running-for-7-minutes-a-day-cuts-risk-of-death-by-30-study-says/
 
2. The history of “Charlie Horses”
 
3. A runner with strange shin bruises.  
from : Joy 
Hi, I’m a great follower of your blog - fascinating stuff! I was wondering if I could ask you a quick question as nobody I’ve spoken to has been able to help:

I’ve been getting bruises that appear on my shin during running. They don’t hurt, I’m just wary of ignoring what could be a warning sign. Have you ever come across this before? (It’s mainly the spot where I had a tibial stress fracture last year, but I also get a few other apparently spontaneous bruises on my lower legs.)
4. Is that a forefoot varus or are you just happy to see me ?
Functional vs Anatomic vs. Compensated forefoot varus foot postures. A loose discussion.
5. A reader’s pet peeve about shoe store “gait analysis”.
6. Thoughts on pronation and the like.
7. Case study:  First toe fusion and implications long and short term.
“I had a patient today with an MTP fusion of his great toe after adverse complications from a bunionectomy.  Do you have any recommendations for gait training when great toe dorsiflexion is no longer an option?  He is currently compensating by externally rotating his foot and overpronating.  I’m thinking through it and  I know he has to gain the motion elsewhere to help normalize his gait as much as possible, so possibly gaining ankle dorsiflexion and hip extension.  Just wondering if you have any tips to share or articles to point me to for further ideas.  Continuing my research now.  I’m a relatively new grad and this is my first patient I’m seeing with this fusion. Many thanks
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Forefoot Valgus or Plantarflexed 1st ray?

Hmmm. That IS the question, isn’t it?

We remember that Forefoot valgus is a condition where the forefoot is everted with respect to the rearfoot.
With a plantar flexed 1st ray, the forefoot is actually in varus (ie inverted) and the the 1st ray is dropped (thus, plantar flexed).

If you look at the picture, you will see the entire forefoot is everted, thus we are  looking at a true forefoot valgus. The question here, is “does the 1st ray move into dorsiflexion”? This would be the difference between a flexible (plastic or rigid deformity and is a function of the rigidity of the subtalar and midtarsal joints as well as the flexibility of the 1st ray.
The literature states that forefoot valgus is the most commonly seen frontal plane deformity of the foot (McPoil 1988, Burns, 1977). We have not found this in clinical practice, but rather forefoot varus. This may be due to most folks seeing us have an issue, and more issues seem to be caused by rigid varus deformities, since they cause the knee to collapse inward.
It’s origin can be multifactorial, ranging from a congenital malformation of the calcaneocuboid joint (more on that joint here) with the absence of a calcanean process, which allows a greater degree of eversion (Bojsen-Moller 1979); over rotation of the talar neck (Sglaraato 1971), or association with a pes cavus foot in compensation to an inverted rearfoot and inflexibilty of the subtalar joint (Lutter 1981). Neuromuscular diseases are believed to cause as many as 95% of these deformities (Dwyer 1975).
The question is, what do we do with it?
  • we insure that the foots mechanics are the best they can be through manipulation and mobilization
  • make sure the joints proximal and distal to the foot are functioning properly
  • muscle test and strengthen weak muscles (think about the poor peroneals in these folks!)
  • make sure they are NOT in a motion control shoe; more flexible is better
  • Make sure their shoe has adequate room in the toe box
  • sometimes, we post the insole of the shoe (or orthotic) in valgus, especially with rigid deformities

A little lost? Take our National Shoe Fit Program, available for instant download 24/7/365 by clicking here.

The Gait Guys. Often a valgus slant on a varus reality. Still bald. Still good looking. Improving your gait competency with each post.

Sometimes, you just need to add a little pressure….

Cyclists are no different than runners; often when the effort is increased (or the conditions reproduced), the compensation (or problem) comes out.

Take a good look at this video of a cyclist that presented with right sided knee pain (patello femoral) that begins at about mile 20, especially after a strong climb (approx 1000 feet of vertical over 6 miles through winding terrain).

The first 7 seconds of him are in the middle chain ring, basically “spinning” ; the last portion of the video are of him in a smaller (harder) gear with much greater effort.

Keep in mind, he has a bilateral forefoot varus, internal tibial torsion, L > R and a right anatomically short leg of approximately 5mm. His left cycling insole is posted with a 3mm forefoot valgus post and he has a 3mm sole lift in the right shoe.

Can you see as his effort is increased how he leans to the right at the top of his pedal stroke of the right foot and his right knee moves toward the center bar more on the downstroke? Go ahead, stop it a few time and step through it frame by frame.  The left knee moves inward toward the center bar during the power stroke from the forefoot valgus post.

So what did we do?

·      Worked on pedal stroke. We gave him drills for gluteal (max and medius) engagement on the down stroke (12 o’clock to 6 o’clock) to assist in controlling the excessive internal spin of the right leg. Simple palpation of the muscle that is supposed to be acting is a great start.

·      Did manual facilitation of the glutes and showed him how to do the same

·      Worked on abdominal engagement during the upstroke (the abs should initiate the movement from 6 o’clock to 12 o’clock)

·      Manually stimulated the external oblique’s

·      Placed a (temporary, hopefully) 5mm varus wedge in his right shoe to slow the internal spin of the right lower extremity

·      Taught him about the foot tripod and appropriate engagement of the long extensors; gave him the standing tripod and lift/spread/reach exercise (again to tame internal spin and maintain arch integrity)

Much of what you have been learning (for as long as you have been following us) can be applied not only to gait, but to whenever the foot contacts anything else.

The Gait Guys. Experts in human movement analysis and providing insight into biomechanical faults and their remediation.

All material copyright 2013 The Gait Guys/The Homunculus Group. Please use your integrity filter and ask before using our stuff. 

Foot “Roll Out” at Toe Off : Do you do this ? And if so, why do YOU do it ?

As we always say, “what you see in someone’s gait is often not the problem, rather a compensatory strategy around the problem”.


What do you see in this case ? We would like to draw your attention at this time to the transition from midfoot stance to toe off on the right foot.  You should watch both feet and note that the right foot tips outward (inverts) as toe off progresses.
What could cause this ?  It is certainly not normal.  Remember, it is highly likely it is not the problem, that something is driving it there or something is not working correctly to drive this client to normal big toe propulsive toe off. Now, there are many other issues in this case, some of which  you can see and many of which you cannot, but do not get distracted here, our point is to talk about that aberrant Right toe off into inversion which prevents the optimal hallux (big toe) toe off. 
A clinical exam will give many answers to joint ranges and what muscles are strong and which are weak and inhibited.  Without the clinical exam and this information about the entire kinetic linkage there is no way to know what is wrong. This thinking should awaken shoe stores when prescribing shoes off of watching clients run or walk on a treadmill.  There is so much to it beyond what one sees. 
So what could be causing this foot to continue its supinatory events from heel strike all the way through lateral toe off ?
The foot could be:
- a rigid high arched cavus foot
- perhaps pronation through the midfoot and forefoot is painful (metatarsal stress pain, painful sesamoiditis, plantar fascitis) so it is an avoidance strategy possibly
- a common one with this gait presentation is perhaps there is a hallux limitus/rigidus (turf toe), painful or non-painful
- weak peronei and/or lateral gastrocsoleus thus failing to drive the foot medially to the big toe during the midstance-to-forefoot loading transition
- contractured medial gastrocsoleus complex (maybe an old achilles tear or reconstruction ?)
-rigid rearfoot deformity not allowing the calcaneus to perform its natural evertion during early stance phases thus maintaining lateral foot pressures the entire time
- presence of a rigid forefoot valgus
- avoidance of the detrimental medial pressures from a forefoot varus

 These and many other issues could be the reason for the aberrant toe off pattern.  This is not an exhaustive list but it should get your brain humming and asking some harder questions, such as (sorry, we have to say it again), “is what you see the problem, or a compensatory strategy to get around the problem ?”

We know you have busy days but we appreciate your time watching our videos and embracing something we are both passionate about.
We are The Gait Guys

Dr. Shawn Allen & Dr. Ivo Waerlop

Podcast #26: Google shoes, shoe tech & indoor track biomechanics

Pod #26: The new Google Shoes, hamstring injuries in short track running and shoe tech.

podcast link: 

http://thegaitguys.libsyn.com/podcast-26-google-shoes-shoe-tech-indoor-track-biomechanics-and-injuries

iTunes link:

https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

Gait Guys online /download store:

http://store.payloadz.com/results/results.aspx?m=80204

other web based Gait Guys lectures:

www.onlinece.com   type in Dr. Waerlop or Dr. Allen  Biomechanics


Today’s show notes:

Two neuroscience pieces today which parlay nicely into last weeks podcast on kurzweils singujlarity

1- Google Shoes

http://www.huffingtonpost.com/2013/03/11/google-shoes_n_2853098.html

http://youtu.be/VcaSwxbRkcE

This weekend, at the annual South by Southwest conference in Austin, Texas, Google unveiled an early prototype of motion-sensing “smart shoes,” with an embedded speaker on the tongue of the shoe that can yell motivation at you when you’re being lazy, or encourage you when you’re being active. Google –which created the talking shoes in collaboration with Adidas,

2- The First Wireless, Implantable Brain-Computer Interface

http://gizmodo.com/5988342/the-first-wireless-implantable-brain+computer-interface-will-help-us-move-things-with-our-minds-on-the-go

3- Problems with small track counterclockwise running

J Mot Behav. 2012;44(1):63-8. doi: 10.1080/00222895.2011.645912. Epub 2012 Jan 13. Asymmetrical neural adaptation in lower leg muscles as a consequence of stereotypical motor training. Ogawa T, Kawashima N, Suzuki S, Nakazawa K.

Clin J Sport Med. 2000 Oct;10(4):245-50. Asymmetrical strength changes and injuries in athletes training on a small radius curve indoor track. Beukeboom C, Birmingham TB, Forwell L, Ohrling D.
4- Puma mobium shoe
http://youtu.be/9cOPMG-TDqw

5- from a Facebook readerI just saw you’re video on hammer toe stretching on tumblr. Great article with it too.
I’ve noticed that on my left foot, my 5th toe doesn’t touch the ground at all when my foot is flat on the ground. It appears not to be doing any work and the pain under the head of my 5th met is getting worse each week now.

6- another facebook question

  • I’ve been doing your shuffle steps and moonwalk to increase my very inflexible ankles. Is there anything else I can do? I read the study and your blog post how stretching doesn’t work. My teammates have literally over twice the dorsiflexion I have and it really shows in my skating. If these two excersises are all that can be done what are the reps/sets/times per week recommendations?

7- Cushioned Heel Running Shoes May Alter Adolescent Biomechanics, Performance
http://www.sciencedaily.com/releases/2013/03/130319091420.htm

Shawn and Ivo

the gait guys

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The Great Myth of Rotating your Shoes : Here are the Actual Facts as we see them.

Everyone has heard the rules, rotate into new shoes about every 400-500 miles.  We disagree, kind of, and we have talked about it on previous blog posts in the past and on our podcasts.  Many shoe reps have agreed with the methods we employ for our runners.

The EVA foam often used in shoe manufacturing has a lifespan, or better put, a given number of compression and shear cycles. It can go through a rather fixed number of compression cycles before it loses its original structural properties, the older the foam gets the faster the degradation process and the more risks it poses for runners.  It is known that EVA foam compressed into a focal vector or area over and over again becomes softer and more giving into that vector/area over time.  Hence, if you have a compensation pattern or a known foot type (forefoot varus, forefoot valgus, rearfoot varus, rearfoot valgus or a combination of these 4) you will break down a certain region or zone of the shoe’s EVA foam. For example a forefoot varus foot type will often drive some heavy focal compression into the foam under the first metatarsal. However, if you combine it with a rear foot valgus it will drive shear forces and compression into the  EVA foam along the entire medial aspect of the shoe (see the 2 pictures attached, you can see the evidence of excessive medial compression and medial shear in a foot that has severe rearfoot valgus and forefoot varus. This is a very poor shoe prescription for the foot type involved).

Here is what you need to do / know:

1- Know your athletes foot type so you can make more informed decisions.

2- Know the type of foam of the shoes you are recommending (ie. Altra uses A-Bound foam instead of EVA just as an example. A-Bound is an environmentally friendly energy-return compound is made of recycled materials. It reduces the impact of hard surfaces while still maintaining ground feedback. Traditional running shoe foam compresses 70-90% while A-Bound™ compresses 2-3x less so it won’t deform over time.).  Cheap shoes use cheap materials.  Altra goes the extra mile for foam quality and many others are beginning to follow suit. If you think you are getting a deal on shoes, know what “the deal” is, it just may be cheaper materials.

3-  500 miles is not the rule for everyone and every shoe.  If you have a relatively neutral forefoot and you are a forefoot or midfoot strike runner you will get far more miles out of a shoe.  If you depend on a stability shoe with dual densities of foam to slow your pronation and control your medial foot because of a rearfoot valgus and/or forefoot varus know that the shoe’s foam will break down less uniformly because of foam interface junctions and whatnot.  This is a science. Engineers call it “the mechanics of material deformation”.  We wonder how many mechanical engineers shoe companies have on board in their R&D divisions ?  We know for a fact that a few do not. There was a reason we snuck quietly into the mechanical engineering departments of our Alma Mater and sat quietly in the “Materials” classes. At the time our roommates just told us it was  cool class, little did we know why it was so interesting to us, until now.

4- Here is what we recommend. Fit the foot type to the right shoe selection. If you are weak in this territory consider taking our intense “National Shoe Fit” program. Fit is everything. Make the wrong choice for your client and the shoes will break down quicker and into poor and risky patterns. Make the right choice and be their hero. If you are looking for a way to improve clientele happiness and store loyalty our Shoe Fit Program is the way. Just read the testimonials here on our blog. Some of the top stores in the Nation have quietly taken the National Shoe Fit Program from us, they have good reason to. They also have good reason to keep it quiet, to get the edge on the competition.

You can email us to get this information and the e-file program download. Why not certify your entire store staff ?

Email us at   thegaitguys@gmail.com.  This program will teach you foot anatomy, functional anatomy, shoe anatomy, foot types and matching foot type to shoe type as well as many other aspects of gait and lower limb biomechanics.

* 5- Try this recommendation.  At 250 miles buy a new shoe to accompany your shoe that already has 250 miles. Now you are rotating 2 shoes. From this 250 mile point moving forward, alternate the newer show with the older shoe. This way you are never in a shoe that is notably more deformed in a specific area of the EVA foam because of your compensations, limitations or foot type. Essentially you are always just a day away from a newer shoe that has less driving force into abnormally compressed EVA foam.  The older the shoe gets the more it accelerates your foot and body into that deformation and hence why many injuries occur as their shoes get older. Continue to alternate shoes on every other run (new, old, new, old).  Once you hit 400-500 miles on the old shoes, ditch them and get a new pair again to restore the cycle once again.  In fact, to be specific here is what we recommend. Monday, old shoe. Tuesday, new shoe. Wednesday do not run, rather, rest or cross train. Thursday go back to the older shoe. Friday new shoe and repeat. This way you are 4 days between runs in the older more deformed shoe. The one day off running in mid week gives tissues that were challenged by the “old shoe run” a bit more time to repair.

6- Dedicate your shoes to running only. Running gait is not the same as walking gait. Why would you want to break down the EVA foam at the rear foot during walking (because heel strike is normal in walking) when in running you are a mid-forefoot striker ?  Keep walking shoes for walking, running shoes for running. Otherwise you are just asking for trouble.

Check out our National Shoe Fit program and certification process here as well as links to our other teaching DVD’s & e-downloads:
 http://store.payloadz.com/results/results.asp?m=80204

Shawn and Ivo. Helping you use your head (and shoe knowledge) better everyday.
The Gait Guys  (have you checked out our RebelMouse page ? https://www.rebelmouse.com/TheGaitGuys/

Keeping up with our awesome informative podcasts ? It is all free stuff ! https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

How about our youtube channel ? http://www.youtube.com/user/thegaitguys

How about our Facebook PAGE ?  https://www.facebook.com/pages/The-Gait-Guys/169366033103080

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READY

The Gait Guys Case of the week: What do you see?

This individual presents with Right achilles tendonitis, bilateral foot pain and a history of plantar fascitis. What do you think?

Take a look at his foot type, particularly the forefoot to rearfoot orientation. Hmmm….Asymmetrical. Notice the dropped 1st metatarsal on the left that is not present on the right. He has a forefoot valgus on the left with a quasi flexible 1st ray (1st ray = medial cuneiform, 1st metatarsal and associated phalanges) which is dropped and an uncompensated forefoot valgus on the right, with an inflexible 1st ray.

He has bilateral external tibial torsion (which you cannot see in these pictures) right greater than left (OK, you can see that), as well as a Left anatomically short leg (tibial) of approximately 7mm.

Now look at the pedographs. BIG difference from left to right. Good tripod on right with clear markings over the calcaneus, the head of 5th metetarsal and the head of 1st metatarsals.  But I thought you said he had an UNCOMPENSATED forefoot valgus ?  Look at the shape of the forefoot print. It is very different from right to left. Remember, with a forefoot valgus, the medial side of the foot hits the ground before the lateral side most of the time,

How about the left? Look at all that metatarsal pressure. Looks like a loss of ankle rocker. Think that might be causing some of that left sided foot pain? Notice the print under the 1st metatarsal is even greater; and look at all that printing of the 5th metatarsal head. Remember, this is the shorter leg side, so this foot will have a tendency to supinate more, thus he increased pressures laterally.

Achilles tendonitis?  Stand on one leg on your foot tripod and rock between the head of your 1st metatrsal and head of the 5th.  Where do you feel the strain? The gastroc/soleus and peroneals. Now put all your weight on the lead of the 1st metatarsal. What do you notice? The foot is everted. What everts the foot? The peroneals. So, if the foot is everted (like in the forefoot valgus), what muscle is left to shoulder the load? Remember also, that the gatroc/soleus group contracts from mid to late stance phase to invert the heel and assist with supination of the foot.

The Gait Guys. Your guiding light to gait literacy and competency.

Want to know more about pedographs? Get a copy of our book here.

All material copyright 2012 The Gait Guys/The Homunculus Group.

Dear Dr. Lieberman : Some vital facts on forefoot running are not being discussed.

A clay pot sitting in the sun will always be a clay pot. It has to go through the white heat of the furnace to become porcelain. -Mildred Wite Stouven.

Today’s blog article is likely to bring flames to our feet, but we are not afraid of the heat.  At the very least we will settle for the heat this article may bring so that our work can get the recognition we feel it deserves and so the truth can be brought to light for the good of all mankind.

“Forefoot strike causes less impact force on the body,” says co-author Daniel Lieberman, Ph.D., a professor of human evolutionary biology at Harvard and scribe of a popular barefoot running manifesto in 2010. “People forget that running is a skill, and if you don’t run properly, you’ll get injured.”

Amen to that; we have been saying that for years before this all became popular talk …

We recently read this article in Men’s Health, yet another one supportive of minimalism running. And once again some of the most important facts are being left out. We just cannot sit here and watch the inaccuracies of minimalism and forefoot running continue to root themselves without policing. So, let us once again set foot into the raging battle.

According to the article (LINK) Sturtz says, “Landing on your forefoot, the way humans have run for thousands of years, produces almost zero impact on joints and bones, according to Lieberman’s 2010 study. But 75 percent of us now land heel first—cushioned running shoes made that possible (and comfortable)—which slams up to 3 times the body’s weight in impact force on your knees and legs.”

Our question is, “ Why is no one paying attention to foot types?” In every lecture we do, to clinicians or everyday runners, about “forefoot type” variants (valgus and varus to be precise) we comment that this is something that should be talked about during Running Form Clinics where forefoot landing is promoted. 

“… forefoot running is not the whole answer to injury prevention, just a component”, says Lieberman. “This is not a simple solution to a complex problem—you can’t change one thing and have everything be fine. You can still forefoot strike with poor form.”

And we would add to that quote that “you can get a resultant compensatory running form if you forefoot strike with a forefoot varus or forefoot valgus”. Not everyone has that pristine neutral forefoot bipod architecture that the internet articles are assuming exists in everyone, and thus there is no way that everyone has fully competent pristine forefoot biomechanics that will not eventually trigger injury. This is a fact, not our opinion. 

Dr Lieberman then goes on to say: “ If it ain’t broke, don’t fix it.”

We respectfully disagree. We do this on a daily basis (as do many of you).  If the check engine light on your dashboard is flashing at you every day for a week you would be remiss not to consider the repercussions.  “The car ain’t broken… YET” is a more precise comment. You would be wise not to go on a long distance car trip knowing this fact.  Translating this to forefoot load/strike running, ignoring a potential injury because of flawed forefoot anatomy and biomechanics is a recipe for injury.  Just because it isn’t broken YET doesn’t mean ignoring the issues will make them go away or make you immune. A few hundred or thousand miles on a forefoot variant can be an issue clinically and injury wise.

Just because the body isn’t broken YET doesn’t mean it cannot work better and prevent a problem down the road. Dr Lieberman then goes on to quote, “Remember, almost every distance runner gets injured".  Why is he batting from both sides of the plate here? If “Landing on your forefoot, the way humans have run for thousands of years, produces almost zero impact on joints and bones”, according to Lieberman’s 2010 study then why would he go on to say “Almost every distance runner gets injured”?  There has to be a reason !  Forefoot running is either the answer or it isn’t.  Our valid and ignored proposal above, and our repeated comments throughout our 500+ blog posts on this topic on foot types, is a valid answer to his injury assumption.  It is quite possible that these inevitable injuries occur because people take the advice of “if it ain’t broken, don’t fix it”.  It is also most likely that ignorance of the deeper facts is bliss for most people. .Had they spent the time to find out about their forefoot type and learn to modify subtle biomechanical flaws of forefoot loading strategies of their foot type, perhaps we wouldn’t hear “Remember, almost every distance runner gets injured".   Maybe that is why you SHOULD look into fixing things that are not YET broken and at the very least learn about foot types, particularly which one you have and the potential risks it exposes you to. Our blog here has done this in depth over the last year. 

“An ounce of prevention is worth a pound of cure” -Benjamin Franklin.  Anyone is medicine knows this is true (or should).

We prefer midfoot strike when possible, for many reasons but mainly because it takes into account a tripod contact loading response.  A tripod load is more stable than a rear foot unipod load and more stable than a forefoot bipod load, particularly when there are rear or forefoot variants (rearfoot valgus, rearfoot varus, forefoot valgus, forefoot varus) from the pristine normal that is always assumed in many articles.   A tripod loading response (midfoot strike) can dampen some of the mechanical flaws of either heel or forefoot strike patterns and of the foot type variants that are the norm, not the exception.

We see this stuff everyday in our practices. We are the guys that get the injury cases that are driven by the inaccuracies, or better put “overlooked facts”, of articles on the internet. To be fair, we have also written a fair number of articles for magazines and we know how they can get so chopped down that truth, honesty and full disclosure can be lost for the sake of publication limitations. None the less, our strong opinion, this article could have been far more complete had it talked about the issues we have brought to light here.  We love and respect the work of Lieberman and his colleagues.  He and his colleagues have done a huge service to the runners of the world and we have learned from them. Learning is a lifelong journey for us all and we just think that there is a huge information gap that is being missed and we feel it is time that the runners of the world hear the whole truth. We believe our work is filling that gap.

“First they ignore you, then they laugh at you, then they fight you, then you win.”

- Mahatma Gandhi

For the past year, we have been feeling a bit like Gandhi must have felt. We realize that some of our work is complicated, difficult to understand, and tough to digest. We know we are laughed at by some who prefer to seek the safety of ignorance. And yes, despite 600 blog posts on these very topics (yes, we have one of the most informative blogs and YouTube Channels on the web for runners and athletes looking for answers) we feel somewhat ignored. None the less, we continue to stick our necks out far and long to set the record straight to make sure that everyone knows the facts they deserve to know.   We hope you will forward, link, Facebook and tweet the hell out of our blog post today, for the good of every runner and athlete you know and for the whole of mankind.  We are in this for the long haul. Stick and stones … .       - Drs. Shawn and Ivo …  The Gait Guys

here is the article that spurred our post:

http://news.menshealth.com/fix-your-running-form/2012/01/24/

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What’s your foot type: Part 4

Forefoot valgus.

In this foot type, the fore foot is everted with respect to the rear foot and the little toe side of the tripod cannot gain purchase on the ground. This foot is a poor lever. The problem here is that in normal ambulation we progress our body mass lateral to medial, which engages normal biomechanics.  In this foot, the body moves from medial to lateral, so we are unable to toe off  from the bog toe side of the tripod. Lack of optimal toe off means poor propulsion strategies from the calf and gluteals. Consequently, patellar tracking is challenged, the limb is in a more relative external rotation, and the peroneal muscles are typically overburdened in an attempt to stabilize the lateral ankle area.

Missing something? Check out the last 3 weeks posts on foot types. Our shoe fit program is launching soon. You too can become certified and become “all that you can be” in shoe fitting.

Ivo and Shawn: Bald…Middle aged…Geeky…Good Looking….promoting foot and gait literacy here on a daily basis

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Forefoot Valgus: What you need to know

Hi Shawn and Ivo,

With Forefoot valgus problems do you find it useful to mobilise the calcaneus? Also any other forms of manual therapy worth addressing before doing the arch strengthening exercises as decribed on youtube?

Also whens your professional presentation on shoes available and also any other ones beside the ones available on wannabefast. I bought all the ones available on wannabefast.

Thanks for your time,
D

Dear D

Appropriate physiological ROM’s are ALWAYS important prior to ANY rehabilitative procedure. So, if you are referring to any of the articulations with the calcaneus (talo-calcaneal (any or all of the 3) and calcaneio-cuboid), yes. The calcanueus needs to evert 4-6 degrees beginning at initial contact through midstance and pathomechanics here would limit subtalar pronation and reduce the shock absorbtion that these joints provide. This could result in a functional forefoot varus. Likewise, if there were no inversion, you would not be able to supinate and the foot would remain in an “unlocked”” position, being a poor lever arm.

It would be prudent to assure all ROM’s are within physiological ranges (or subluxation free) before proceeding with exercises.

Watch for our Show fit program, which is in the final editing stages. Stay tuned here or on our Facebook page for details.

The Gait Geeks

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The Risks for Forefoot Strike running. YOU NEED TO READ THIS ! YES, YOU !

OK, we are going to go on a rant here…… it is time.

We have been talking about problems of forefoot strike for some time now. We like a midfoot strike, and we have research-based, well founded logic to our opinion.  A Forefoot strike reduces the amount of pronation possible for shock absorption because  when the foot is plantarflexed it is in a supinated state which is reserved for a rigid propulsive mechanism.  At impact some degree of pronation is necessary otherwise force attenuation must occur elsewhere in the kinetic chain otherwise it creates bone, joint or soft tissue pathology/injury somewhere in the chain.  However, one of the major issues we have been pounding our fists on the table about, for years, are forefoot orientation anomalies.  A significant portion of the population have forefoot types of varus or valgus, some flexible and some more rigid, some compensated and some uncompenated (yes, this is difficult stuff……but if you are going to make orthotics or if you are going to be a runner or sell or make shoes or coach or even speak about running form styles…… you had better know this stuff or we will call you out on it). 

No one is talking about this stuff except The Gait Guys. 

Is this because no one knows about it ? Maybe.

It is because those in the running fields do not understand it well ? Likely. 

It is because it creates fear and anxiety about selling shoes ? Probably.

Is it because it complicates shoe fabrication? Likely. 

Does that make it right to just ignore it all together ? No ! 

With a forefoot strike into one of these “pathologic” forefoot types the anatomical variance is accentuated.  In this scenario, a varus foot type that lands and subsequently has not choice but to drive hyperpronation strain not only suffers from the increased pronatory collapse but they are unable to acquire a subsequent rigid toe off which in itself can drive further pathology.  And a valgus forefoot strike is even more rigid than a neutral forefoot strike impact and they are also at risk for inversion strain on the lateral foot.  A midfoot strike can reduce some of these consequences by setting the foot up for a preparatory transition. We know this, we see this everyday, it is what we do. These runners need to be categorized and educated as to why their injury is present or chronically persists, and why we insist a program to reteach a midfoot strike. 

As always, if the doctor knows what anatomy presents itself with the client, and adequately educates the athlete……..then a good relationship and outcome will ensue. Additionally, a change in shoe is not  uncommon when their strike mechanics change.


Here is what spurred our soapbox rant today…….. thanks Lower Extremity Review for bringing the June ASCM to light early !!!
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from LER, Link is above:

“The frequency content of vertical ground reaction forces generated during running differ among forefoot strikers and rearfoot strikers, and this may have implications for injury risk, according to findings from the University of Massachusetts presented in June at the ACSM meeting.

Researchers assessed frequency amplitude and power in 10 natural rearfoot strikers and 10 natural forefoot strikers as they ran across a force platform.

At frequencies above 9 Hz, rearfoot strikers’ amplitude exceeded that of forefoot strikers. Similarly, above 22 Hz, power was significantly greater in rearfoot strikers. This is consistent with previous reports that only rearfoot strikers have an impact peak, which occurs between 10 Hz and 20 Hz.

But between 4 Hz and 7 Hz, amplitudes were higher in forefoot strikers. And for frequencies less than 6 Hz and between 9 Hz and 11 Hz, power was greater in forefoot strikers.

Because the body attenuates shock differently at different frequencies, the findings could suggest that even forefoot strikers (including most barefoot runners) may be at risk for certain injuries despite lacking an impact peak.”

Advanced Gait and Running Topics: Biomechanics, Details of Foot types, Multiple Case Studies

another course offering is now available for your viewing.

The course by The Gait Guys, Biomechanics 203: Advanced Gait and Running Topics: Biomechanics, Details of Foot types, Multiple Case Studies.  3 hour lecture, segemented.  This is one of our long awaited courses.  Tons of detailed materials in this course.  (available for 3 hours continuing education).

Whether  you are looking for continuing education credits, or just looking to learn more about true foot function and how it integrates with the rest of the body…….this is a great lecture.

  • More discussion on the walking and running gait cycles
  • Apply the biomechanics of the pelvis and lower kinetic chain during walking to clinical practice
  • Predict and discuss problems and clinical strategies that can arise from altered lower extremity biomechanics
  • Apply visual analysis skills
  • Evaluate case studies in gait analysis
  • Clinically apply solutions for gait abnormalities
  • video case studies mingled into each topic

Click the link above, when you get to the website, choose CONTINUING EDUCATION COURSES, and from the pull down menu select CHIROPRACTIC DOCTOR.  Look under BIOMECHANCS, select course 203.

Enjoy