The Tarhumara and Masai      Part 2

Setting things straight:  MBT (Masai Barefoot Technology) Shoes: Are they really “the Anti-shoe” ?  

In the past, many of you have read our articles and opinions on barefoot walking and running As time has gone on you have seen the results of the work we have done for Vibram on their product the Five Fingers (http://www.vibramfivefingers.com/technology/faqs_board.cfm).  This Vibram device is the closest to true barefoot walking or running. There are now products in the stores such as the Nike Free and the MBT shoe that over the last few years are gaining popularity. Our job, as we see it, is to report the facts, so here they are.

In 2008 in Outside magazine there appeared an ad for the MBT shoes claiming they are the “anti-shoe, anti-boot, anti-sandal etc”.  They imply on their training videos, website and advertisements that this shoe improves posture, protects your knees and tones your muscles, apparently from just standing in them.  We think this must be a pretty amazing shoe if it can do all that!  However, if your radar is up and working, you should be asking some hard questions before you spend over $230 for a pair of shoes that challenge you each moment not to roll your ankle in the parking lot outside the very store you bought them in. And now, they are available in similar form from Sketchers as “Shape Up’s”, usually for under $100. We say…save your money and invest it in something else, unless you are one of the select few that could benefit from this technology.

Here are some of our major concerns, questions and reasoning for our harsh but sound skepticism. 

If you pick up this rather hefty shoe you will notice two things immediately, both of which have concerns.  First, the shoe has a rigid last, meaning the shoe does not bend. It has a beveled bottom design called a rocker designed to rock on the ground both forward and backward like a rocking chair.  We think Perry put it best: progression of gait over the supporting foot depends on 3 functional rockers. 

heel rocker: the heel is the fulcrum as the foot rolls into plantar flexion. The pretibial muscles eccentrically contract to decelerate the foot drop and pull the tibia forward.

ankle rocker: the ankle is the fulcrum and the tibia rolls forward due to forward momentum. The soleus eccentrically contracts to decelerate the forward progression of the tibia over the talus. Ankle and forefoot rocker can be compromised by imbalances in strength and length of the gastroc/soleus group and anterior compartment muscles.

forefoot rocker: tibial progression continues and the gastroc/soleus groups contract to decelerate the rate of forward limb movement. This, along with forward momentum, passive tension in the posterior compartment muscles, active contraction of the posterior compartment and the windlass effect of the plantar fascia  results in heel lift.

This shoe takes away from the 3 natural rockers of the foot and means that the foot is not required to do much work other than stand on the platform and let the shoe do the work. In essence, taking it to an extreme, this shoe is really no different than the rocker boot (CAM walker) you might wear on your foot after a fracture, foot surgery or if you have a Hallux rigidus.  They are designed to limit mechanical forces traveling through the foot by making the foot quiet, protected and unchallenged by external forces.  The rocker boots are designed to reduce heel impact load, and thus induce a more gently rockered mid-foot impact loading, “softening” pronation, which reduces force into the foot. The MBT, at least according to 1 study, lessens heel strike pressure by 11%, but it also diminishes midfoot pressures by 21% and increased forefoot pressures by 76% ! If there is a forefoot deformity, such as a vlagus or varus, this may actualy accentuate pathology, since you are in essence limiting pronation, one of the shock absorbing mechanisms of the foot.

As the studies cite, we agree that they are altering muscle forces through the foot,  but is this a good biomechanical change for the the particular foot or foot type involved and should not depend on a shoe to do it for you.  More importantly, these changes may have a concerning detrimental side effect; the rigidity of the shoe’s last and its rocker will, in time we believe, weaken the foot intrinsics which are critical for joint protection and stability.  The best example we can give are the progressive deformities of hammer toes, bunions and “falling arches” all that result from progressive weakening of the foot intrinsics . This works on the principle of “if you don’t use it, you lose it”. 

The second thing you will notice when you pick up an MBT shoe is that the heel “crash zone” (the area that is first impacted at heel strike) is filled with an exceptionally spongy EVA foam, almost as soft as a wet sponge.  This “crash zone” is extensive and reaches all the way into the beginning of the mid-foot impact zone.  Being the shoe nerds that we are, we can say with confidence that we have never see a shoe with such a soft and expansive rear heel crash zone (not even the Nike Cesium’s (of several years ago) crash zone can compete with this MBT heel zone… and that is saying alot). From what we can tell, this aspect of the MBT shoe was designed to reduce heel strike weight bearing which has some merits, albeit few, particularly in running. When walking, by avoiding heel strike, you are forced to shorten your stride, keep your body mass over the feet and hence reduce the challenges on the pelvis and core in the sagittal plane (these are some of the postural benefits that the shoe claims). 

The Masai tribesman (whom the shoe is apparently named after) are a pastoral people who are herders and walk long distances. They ARE NOT runners and often wear simple sandals adorned with beads or sometimes, go barefoot.

If one walks or runs in shoes with a traditional “heel strike” type gait, the cushioning of the EVA heel sole affords a pillow effect, enabling one to “stride out” and achieve heel strike. This is an undesirable trait. At heel strike, there is a deceleration moment of your body mass, this means a shear force on the ground which is why your brain will not allow you to barefoot heel strike when running on a hard, rough surface.

So the question remains: Is the MBT shoe really promoting barefoot biomechanics or is it just using the exceptionally spongy rear crash zone of the shoe which help one to avoid heel strike ?  We think the latter.  Forcing someone to avoid heel impact/strike naturally forces you to make contact at mid-foot or forefoot (the latter which is bad). For the most part, a midfoot strike is desirable if you have the core stability to withstand this sudden change in gait and posture. Do you really need an expensive shoe to force you to do that when you can make that conscious choice on your own ?

Posture is earned, not forced.  Putting a cervical collar around your neck does not earn you posture, it borrows that posture from an external device.  The MBT shoes does much the same. 

On a positive note, a good use for the MBT shoe is for persons suffering from big toe pain from anatomic (as opposed to functioal), Hallux rigidus/limitus (aka. turf toe) People with limited dorsiflexion of the 1st mmetatarsal-phalangeal joint do well in this shoe since the last of the shoe is rigid and rockered; so the toe does not bend and this reduces pain at the joint. Because of its mass and size, it also makes an excellent doorstop.

The bottom line, if you want to walk or run barefoot, you want to mico-progress into a more minimalistic shoe that bends and gives to motion rather than one which restricts or induces any motion.  If trained properly (and there is an exercise progression for the feet, which is specific for each individual) many feet can become stronger and more competent and necessitate less of a shoe. In our experience, inhibiting joint motion and muscular functions over time leads to bigger muscular incompetences, weaknesses and problems that foot intrinsic weaknesses have been known to lead to such as bunions, hammer and claw toes, neuromas and the like. 

Parts of this article are from an article we wrote years ago when the MBT’s first became available. As far as we know, we were one of the first on the block to write about them and the above issues.  Tomorrow we hope to dig up our podcast we did back then, regarding some of these and other issues….. a little blast from the past, with still great relevance today.

We remain….The Gait Guys…Telling it like it is….

The Tarahumara and Masai             Part 1.

Were they really barefoot? Dr Ivo Waerlop of the Gait Guys dispels some myths.

Here is the same video of the Cyborg Gait, slowed down and looped twice (for your viewing pleasure!). This guy sure has strong hip flexors and most certainly a sore low back! He is probably on his way to the the chiropractor!

Continuing Education courses we have on the web.

Goto:  www.onlineCE.com or www.chirocredit.com

Biomechanics 201: Basics of Gait (4 hours)
Biomechanics 202: Foot Function and the Effects on the Core and Body Dynamics (1 hour)

Biomechanics 310: Advanced Gait and Running Topics (  3 hours)

Rehab 117: Lunges, Squats, advanced Squats and Gluteal Exercises (2 hours)
Rehab 116: Advanced Core Stabilization Concepts (1 hour)
Rehab 115: Core activation Training (1 hour)
Rehab 114: Performance Theories and Core Training Concepts (1 hour)

Acupuncture 211: Qi and The Pertinent Pericardium  (1 hour)
Acupuncture 210: The San Jiao: a closer look (3 hours)
Acupuncture 209: Points and Acupuncture Points You Should Know (1 hour)
Acupuncture 208: Needle Manipulation Technique (1 hour)
Acupuncture 207: Effects on pain modulation and musculoskeletal function (2 hours)
Acupuncture 206: Homeostatic Points (3 hours)
Acupuncture 205: Needles manipulation, Most common points, and Tongue (1 hour)

Dr Waerlop of The Gait Guys discusses the often little known history of the Marathon.

Give us your tired, your poor, your huddled….feet!

We are introducing “Footloose Fridays” or “The Ministry of Silly Gaits”. Each Friday we will publish one of YOUR pictures or videos of feet, shoes or gait that YOU send US! They can can funny, entertaining, strange, happy, you name it. Cartoon feet, dirty feet, sexy feet, big feet, the choice is yours. Keep ‘em coming!!

Gait lecture

Today we are giving a 3 hour advanced gait lecture in a live webinar format.

It is being recorded so that  you can watch the lecture anytime you want.  Goto onlineCE.com or  chirocredit.com

*TeleSeminar Biomechanics 310

Educational Objectives. Following this course, the participant will be able to:

• Discuss the normal walking gait cycle
• 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

Not all that glitters is gold… Or The Black Plague Revisited

Yesterdays post discussed our subungual/friction differential of the phalanyx and sock liner theory.  A word of caution is warranted, as there is a small chance that the lesion could be something more serious. It turns out that a small percentage represent malignant lesions. http://www.ncbi.nlm.nih.gov/pubmed/21554050.

Know the ABC(DEF)’s of a melanoma. Age (50-70), Black or Brown lesion with 3mm or greater breadth, Change (or lack of) in nail or nail bed despite treatment, Digit most involved, Extension of pigment into the lateral nail fold, Family or personal history.

Don’t believe us, read it here: http://www.ncbi.nlm.nih.gov/pubmed/10642684.

Yup, Black Plague or not, we remain The Gait Guys,

The Black Plague (ok, kinda sort of)……Subungal Hematomas in Runners. Blood under the toe nail.  Not what you think it is from !

There are two pictures here, cursor to the right and see the slider that will toggle between the two photos. The photo with bandaid credit given to www.healthandrunning.com the other photo……is a runner client of ours with both a callus pattern on the tip of the 2nd toe and an early small subungal hematoma (read on !)

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We get inquiries about the black toe nail “Syndrome”……aka…..blood under the toe nails in our runners, and how to avoid them. Lets look at this phenomenon as it pertains to the foot.

This problem has a clinical name, “subungual hematoma”. It means a collection of blood under the finger or toe nail.  There are many causes of the subungal hematoma (SH for short as we move forward here).  Here are a few, but we have yet to find any good journal articles for one cause that we are seeing as a possible cause…one we will discuss here shortly. 

One cause is obvious, the crush injury where someone steps on your toe, you drop something onto it or smash it into something.  This is something we have all done at some time. 

 The most commonly theory of cause is repetitive trauma, thought to be that of repeated impact of the toe into the top or end of the shoe.  Heim et al  noted this in 2000.  This really got us to thinking.  Why, when we see these SH’s, do the runners never seem to have shoes that are too short / small or shoe signs of friction (wear patterning) of the toe nail into the top of the shoe’s upper ?  Often the runners insist there has been no such contact within the shoe.  So we started our own investigation making sure to ask all our runners what they thought and felt as they ramped up their miles in prep for marathons and 20 mile runs or daily doubles, particularly those who seemed regularly susceptible to SH’s.  We will discuss our findings and thoughts momentarily, but lets get back to some of the more well known information on SH’s.

The medical literature is full of other types of causes or clues of SH’s that must be investigated, such as medication reactions, autoimmune skin disorders, melanoma, blood disorders (dyscracias or clotting problems). These certainly are not the norm.

It is important to know the anatomy of the area because the nail bed is very rich in vasculature (hence the hematoma creation) and nerve endings (hence the pain) when blood collects in the confined area or it gets torn off from trauma.  The nail bed is a derivative of the epidermis containing keratin which gives it its hard nature. The nail grows from a nail root in front of the cuticle and grows distally at a slow but (usually) steady rate.  This area is frequently susceptible to fungal infections which destroy the tissue in the area and possibly make SH’s more common.

We will not get into the aggressive treatment of things here because that is 1) not our purpose here and 2) we do not want to be accountable for people getting infections  from boring a hole into the nail bed (trephine) to release the blood or the consequences of using plyers to yank it off.  We just tend to recommend they be left alone and let nature take its course.  (For those bold and tough gang, who chose the plyers method, you should know that there is no fatty tissue beneath the nail and the underlying bone to cushion the area, the nail is the only protection; furthermore you should know that the extensor tendon attachment is awfully close to the proximal nail bed root area !).  But when pain it too much, we have our people we refer these cases to.  Rather, we tend to look for a cause of the problem. 

In a limited number of cases we do see a shallow toe box where there is little room for toe extension, thus the nail can get rubbed on the roof of the toe box repeatedly causing a lifting action of the nail from its vascular bed.  This a more plausable cause in our opinion over the “toes hitting the end of the shoe” phenomenon put out there by many sources.  Particularly when most people size their shoes sufficiently long enough for the distal foot slip migration that occurs at mid-foot load within the shoe.  In  these cases a close cropping of the toe nail shoe stop the lifting/friction phenomena on the toe box roof. 

However, we seem to be seeing a more frequent trend that we wanted to share  here.  It seems to go hand in hand with the plague of flexor dominance in our society these days.  What we are seeing is a predominance of toe flexion (either a gentle or marked toe flexion ….we sometimes refer to it as toe hammering) in our runners.  This just makes sense because of the posterior compartment dominance in runners.  (The posterior compartment is made up of the gastroc-soleus complex, long toe flexors and tibialis posterior).  So if this compartment is dominant, and there is not sufficient home work to off set the flexor dominance with extensor exercises, then this flexion dominance will continue and possibly worsen.  As you will see either in yourself, our photo here, or on the feet of many of your co-runners is a distal “tip of the toe” callus development (usually most on the second toe, and less moving into the more lateral toes) immediately below the leading edge of the toe nail.  This callus coincides well with a distal gripping phenomenon of the long flexors (Flexor digitorum longus). So, now imagine, to get the callus there must be repeated friction and since the toe is not hitting the end of the shoe it must be friction into the sock liner bed of the shoe. And if this is the case, the skin is pulled at a differential rate over the distal phalange than the nail bed there will be a net lifting response of the nail from its bed as the skin is drawn forward of the backward drawn phalange  (put another way, the callused toe tip is fixed to the sock liner for grip, and then the phalange is drawn backwards from this contact point creating a NET movement of skin forward thus lifting the nail from its bedding).  [For an at-home example of this, put your hand flat on a table top. Now activate your distal long finger flexors so that only the tip of the fingers are in contact with the table top.  Now, without letting the finger tip-skin contact point move at all, go ahead and increase your long flexor tone/pull fairly aggressively. I defy you to not feel some  pressure building under the distal tip of the finger nail as the skin is RELATIVELY drawn forward.]   And with the nail bed being so vascular, micro bleeding can occur.  This bleeding is slow and takes time.  Which brings the big question to light, SH’s seem to mostly occur on very long runs, and never on short runs (where there is not enough nail bed separation repeatedly to create enough damage to bleed, not to mention fatigue of the other toe/foot intrinsic muscles thus necessitating more use of the more powerful long toe flexors.)

There  does not seem to be anything out there in the information on this supposition.  Maybe we are crazy…….but we do see alot of runners.  And once we bring the awareness of the problem to our runners and show them  how to reduce the flexion dominance with exercises to gain more extension balance, do we see an arrest of any further Subungal hematomas. 

We would love to hear your thoughts and experiences with them, both clinically and as a runner. Let us know what you think about our plausable cause. 

we remain……The Gait Guys

Do you know how you run?

If the answer is yes, then the second question is ”How would your running technique change if you were bare foot?” 

The reason these questions are important is straightforward.  We think your body was designed to do its job best without shoes.

Stepping backwards in time a little, in the caveman days things were different.  The foot was unshod (without shoes) from the moment of the first step until one’s dying day, and thus the foot developed and looked different.  The sole of the foot was thicker and callused due to the constant contact with rough and offending surfaces thus preventing skin penetration. The foot proper was more muscular and it was often wider in the forefoot and the toes were likely slightly separated due to the demands of gripping, which would necessitate increased muscular strength and bulk to the foot intrinsic muscles. 

It was the constant input of uneven and offending surfaces such as rocks, twigs, mud, foliage and debris that stimulated the bottom of the foot, and thus the intrinsic muscles, sensing joint positions and relaying those variations to the brain for corresponding descending motor changes and adaptations to maintain protection and balance.  The foot simply worked different, it worked better, and it worked more like the engineering marvel that it truly is. 

Most animals on this planet run on their toes or forefoot. This allows for a more active control of the impact that will be placed on the lower leg, which in turn will decrease the rate of  injury. If you have a large heel cushion and you land on your heel you are asking the cushion to take the place of your brain. The last time we checked, air filled foam couldn’t think all that well.  In the last few years  there has been a return to bare foot running. But it is not necessary to go barefoot to gain the benefits. You can just change your running style. 

When running either shod or unshod, to minimize injury, try and remember the following points:

Where does your foot strike the ground? Your point of contact or strike should be somewhere between the mid foot and the ball of the foot.

Where is your center of gravity relative to your point of contact with the ground? Your center of gravity, which is located in about 2 inches below your belly button and in the center of your abdomen, should be directly over or slightly forward of your point of contact.  This is accomplished by leaning forward at the ankle.

Make sure you activate your core muscles, including your abdominals and glutes. Your abdominals should be active when your foot is in the air and your gluteals when your foot is on the ground.

This is how you would run if you were bare foot and it is how you should run in shoes. If you do nothing but apply these to changes to your running you will be well on your way to becoming a more effective runner. 

The Gait Guys give special thanks to Dr John Asthalter, who contributed to this article

Beautiful Glutes: Part 3

Here is the part you have been waiting for…

Functional Perspectives

It would logically follow that the gluteus medius is important for generating both forward progression and support, especially during single-limb stance suggesting that walking dynamics are influenced by non-sagittal muscles, such as the gluteus medius, even though walking is primarily a sagittal-plane task. After midstance, but before contralateral preswing, support is generated primarily by gluteus maximus, vasti, and posterior gluteus medius/minimus; these muscles are responsible for the first peak seen in the vertical ground-reaction force. The majority of support in midstance was provided by gluteus medius/minimus, with gravity assisting significantly as well.

Seemingly, the gluteals appear important for extension of the thigh during gait. One of the most common scenarios appears to be a loss of ankle rocker and resultant weakness of the gluteals (personal observations). Lets look at an example.

Have you ever sat at the airport and watched people walk? We all travel a great deal and often find ourselves passing the time by observing others gait. It provides clues to a plethora of biomechanical faults in the lower kinetic chain, like a loss of ankle rocker with people who wear flip flops or any other open backed shoes.

What is ankle rocker, anyway? According to Jaqueline Perry (THE Matriarch of Gait Analysis) during normal gait, the stance phase (weight bearing) foot depends on 3 functional rockers (pivots or fulcrums) for forward progression.

· heel rocker: at heel strike, the calacaneus acts as the fulcrum as the foot rolls about the heel into plantar flexion of about 10 degrees . The pretibial muscles must contract eccentrically to slowly lower the foot and help, along with forward momentum, pull the tibia forward

· ankle rocker: next, the ankle acts as at fulcrum and the tibia rolls forward due to forward momentum, with a maximum excursion of approximately 15 degrees. The gastroc and soleus should eccentrically contract to decelerate the forward progression of the lower leg.

· forefoot rocker: the metatarso-phalangeal joints act at the final fulcrum in the stance phase of gait. Note that the 1st metatrso-phalangeal joint must dorsiflex 65 degrees for normal forward progression, otherwise the individual will usually roll off he inside of the great toe. Tibial progression continues forward and the gastroc/soleus groups concentrically contract to decelerate the rate of forward limb movement. This, along with passive tension in the posterior compartment muscles, forward momentum , and the windlass effect of the plantar fascia result in heel lift.

Now watch someone walking in flip flops or open back shoes. There is no pivot past 90 degrees at the ankle (i.e. the tibia never goes beyond 90 degrees vertical). At this point the heel comes up (premature heel rise) and the motion must occur at the metatarso-phalalgeal joint. The only problem is that this joint usually has a maximum of 65 degrees extension. Since more is now needed, the body borrows from an adjacent joints, namely the knee (which increases flexion) and the interphalangeal joints (which should be remaining flat and now must claw to “create” more available extension at the middle joint, as the proximal is nearly fully extended, through overactivity of the flexor digitorum longus. The tibialis posterior, flexor hallicus longus, and gastroc soleus groups also contract in an attempt to help stabilize the foot . Overactivity of these groups causes reciprocal inhibition of the long toe extensors and ankle dorsiflexors (tibialis anterior for example), causing the toes to buckle further and a loss of ankle dorsiflexion; in short, diminished ankle rocker function.

So there you have it. Glutes. They are a beautiful thing! Isn’t it great to be a gait nerd?

We remain..Gait Nerds and ….The Gait Guys….

Beautiful Glutes: Part 2

We are going to get a little techie here. Hang in there!

EMG data

There are a paucity of studies on gluteal function during gait, but here is what is out there.

The upper and lower portions of the glute max shows activity at initial contact and near the end of swing phase, the middle portion additionally just before and after pre-swing.  The glute max does not appear to be a postural control muscle, nor is it utilized in static one leg standing, except when a large load is imposed  When the center of gravity of the whole body is grossly shifted, the gluteus maximus becomes engaged. The glute max, along with the vasti also assist in deceleration of the body during the first half of stance.

The gluteus medius and minimus appear to play a much more substantial role in propulsion and stabilization during normal gait, contracting from terminal swing to preswing, maximally during early midstance, to prevent contralateral drop of the pelvis. The anterior fibers of both appear important for gait, as they assist the external obliques in forward progression of the pelvis on the side oppposite the stance phase leg, in addition to supplying coronal plane stabilization. A brief burst of activity in midswing assists in medial rotation of the thigh. Gluteus maximus fuction can be affected by  altered biomechanics and the g luteus medius commonly affected by postural faults.

Wow, betcha didn’t know that! Stay tuned for part 3!

We remain…The Gait Guys.

Beautiful Glutes!     Part 1

Place your hands on your buttocks and stand up from a seated position. Did you feel them fire? Now walk with your hands in your back pockets. Do you feel them active at the end of your stride? No? Maybe you should be in rehab. You should!

The glutes have been the fascination of many, including Michaelangelo (Ever seen the sculpture of David?). Perhaps if you have a patient with recalcitrant back or hip problems, you should consider looking closer at their gluteal group.

anatomical perspectives

The gluteus maximus, the most superficial of the 3 gluteii, is the largest, coarsest fibered muscle in the body. It attaches proximally on the ilia, sacrum, coccyx and sacrotuberous ligament and slopes 45 degrees inferolaterally to attach distally, predominantly to the iliotibial tract with a smaller contribution attaching to the gluteal tuberosity of the femur. In open chain, it is an extender and lateral rotator of the thigh, as well as the upper fibers acting as abductors and lower fibers adductors of the hip.

The superior fibers of the gluteus maximus are part of the lateral line of musculature (as described by Myers in “Anatomy Trains”) as it diverges at the hip, along with the gluteus medius and tenor fascia lata. This lateral line helps provide stabilization in the saggital plane, beginning at the peroneus longus and traveling ultimately to the splenius and sternocleidomastoid. From this perspective, we can view gluteal function during gait (ie closed chain) as rotators and abductors/adductors of the pelvis and an extensor of the torso

The gluteus medius and minimus attach proximally between the anterior and posterior gluteal lines and distally at the lateral surface of the greater trochanter for the former and anteriorly for the latter . They act as abductors and medial rotators of the thigh in open chain, and abductors and external rotators of the pelvis in closed chain,  the anterior fibers of the minimus and medius probably assisting in forward motion of he contralateral pelvis. Sahrmann states “the posterior portions of the medius act as abductors, external rotator and extenders of the thigh, with the anterior portion also assisting in hip flexion”.

The Glutes; they’re more than just another pretty muscle….

We are…The Gait Guys

There are 2 photos here (move your cursor over to the little triangle on the right to highlight the bar to toggle between photos)

Can you believe that an experienced runner would let a pair of shoes get this far on both sides.  This person does a few marathons a year and has been a patient of our for years…..he tends to milk out every last step in a pair of shoes but we had to hog-tie him and flog him repeatedly for going overboard this time. I bet there had to be 2000 miles on these puppies !  And get this…..he had no foot or knee pain ! (his response was, i saw the wear but i was not having any issues).

Can you imagine how far out side the contact line the knees had to be ? This has the old Nike Cesium beat by a long shot (they were rear foot posted varus by about 3degrees). Heck, this could be 20-25degrees varus !  There is no question that he is avoiding and rear or mid foot pronation……the dude is fixed in supination. 

OF clinical note, he has a fixed right hallux limtus (turf toe) so this likely helps him to avoid medial toe off and forcing dorsiflexion through the big toe joint……however, there are better strategies than this to avoid a hearty toe off !

It is amazing what the body can endure !  Take this as a lesson of what NOT TO DO !  keep the miles between 400-500 miles gang……there are only so many compression cycles in EVA foam before deformation occurs.  In this case there was both deformation and just pure and simple friction wear !

PS: this was an easy pick up clinically……he sat in the waiting room with the 55 gallon barrel set beside him ….the one that he had been carrying around between his knees to force this much rear foot varus !

Short discussion on the toe extensor muscles

We received a great question from a doctor active on our Facebook page (Thegaitguys PAGE, not our user portfolio, make sure you are on the “PAGE”)
Here was the comment:I do like the crouch gaits to help with proximal muscle activation. However I am still not sold on the long toe extensor activation. It would seem to me that the function of this muscle in close chain (ie gait) would be more to aid in pulli…ng the body over the talus (while keeping the toes fully anchored and wide) as opposed to extending the distal phalanx in an open chain fashion. While open chain exercises may ‘strengthen’ this muscle the neurological processing would seem to be different than closed chain and therefore the transfer to more dynamic exercises would be difficult.? I would think that it would not necessarily change the gait but instead allow for better compensatory strength and durability. Although I still have yet to develop a great exercise for this closed chain control. Any ideas?See More

10 hours ago · LikeUnlike

The Gait Guys when you activate the toe extensors the arch is increased from the windlass mechanism across the metatarsophalangeal joints. Raising the arch will help bring it to neutral since the crouched gait is a pronation challenge. give it a try…..…….try the crouch shuffles with toes down and toes up…..you will feel the increased demand on the anterior leg compartment, the greater awareness of the foot tripod esp the first metatarsal head anchor point and the improved ability to control the internal tibial spin (and pronation challenge( that occurs with shuffling with toes down. Remember, closed chain is not any more important that open chain activities……arm swing it gait is open chain but it is necessary…..leg swing is open chain but it is necessary for normal progression and pelvic/core use. also remember……we are a flexor dominant society…..look at how many of your clients toes have either a gentle flexion to them or significant…..the balance of the function across the metatarsophalangeal joint is necessary on balance of extensors and flexors……the shuffle gait with toes up is a huge challenge to the toe extensors……that feeling of the strain on the top of the foot and into the shin is confirmatory. OF course, you are right in what you said……but to get the toes optimally anchored you have to have enough long toe extensor strength to override the long flexor dominance…..otherwise you being hammering the toes and enter into the spiraling vortex of flexor dominance, lumbrical inhibition, short extensor overactivation, proximal fat pad drag etc.

Good Form video from Newton→

Great little video from Danny at Newton…….it doesnt matter what shoe you have if your technique is crummy. Here he demonstrates very well what good contact form is……..we like to say…..“land so subtle on the forefoot that it is a hair distance to kiss your heel to the ground before you push off…..if you remain high on your forefoot at contact you lose your shock absorption because the foot mechanics are more close to supination.”

Shoe Anatomy 101:

If you are truly to be a shoe geek, then you must be familiar with some “shoe anatomy.” Simply put, there is the sole ( the part that contacts the ground), the midsole (the part right between the sole and the last), the shank (the stiff rear part of the midsole), the last (the part on top of the midsole and where the insert or orthotic will sit), the insole (the removable insert), the upper (the part above the last that has the sides, laces, etc)the heel counter (the part that holds the heel in place), and the toe box.

Lets discuss each in turn

The Sole (also called the outsole)

This is the part of the shoe that comes in contact with the ground. It is usually made of rubber and provides for some degree of shock absorption and traction. For running shoes, it is usually cemented to the midsole.

Remember that the heel strikes the ground at approximately a 16° angle lateral from the center of the heel  (in a heel strike gait, no we aren’t condoning this, this is how shoes are designed).  The force is then transmitted from the sole of the shoe, up the lateral column of the foot and across to the first metatarsal for propulsion.  This can be assisted by a “rocker” which is a “drop” put into the front portion of some stiffer trail shoes, to ease walking and assist in toe off.  (This is good for people with Morton’s toes or hallux rigidus).

A flare to the sole of the shoe, particularly lateral can be important for stability on uneven surfaces.  A lateral flare provides extra stability upon heel strike, but it speeds up the rate of pronation.  This may be a bad thing, depending on your feet. This flare must extend the length of the sole, otherwise injury can occur at the mid tarsal joint as the foot comes through mid stance. A medial flare can help to prevent overpronation, as the foot comes through mid stance. Again, it must run the length of the shoe.

Look at the lugs on the sole. Are they beveled or straight? A straight lug or cleat will hold on to mud, whereas a beveled one will shed it. This is an important consideration if running off road. How about the cleat pattern (front vs. back and side to side)? Are they symmetrical or opposing? Opposing patterns will enable you to ascend and descend easier at the expense of a slight amount of speed.

The Midsole (sandwiched between the sole and upper)

Midsole material is very important, as it will accommodate to the load imposed on it from the person and their body weight. It serves as the intermediary for load transfer between the ground and the person.  Softer density material in the heel of the shoe softens the forces acting at heel strike and is good for impact and shock absorption. The stiffer the material, the more motion control.  Air is an excellent shock absorber, however it does not deform, it displaces. This creates and unstable surface for the foot, promoting ankle injuries. Foam and gel are much better as they transduce the force and dissipate it. Often midsoles are made with something called “dual density”.  This means that the midsole is softer on its lateral aspect, to absorb force and decrease the velocity of pronation during heel strike and midstance, with a firmer material medially that protects against overpronation as you come through mid stance and go through toe off.

The Shank (this can be within the midsole)

The shank is the stiff area of the shoe between the heel to the transverse tarsal joint. It corresponds to the medial longitudinal arch of the foot, provides torsional rigidity to this shoe and helps to limit the amount of pronation and motion at the subtalar and mid tarsal joints.

The Last (the part between the midsole and insole)

The last (look inside the shoe on top of the shank) is the surface that the insole of the shoe lays on, where the sole and upper are attached).    Shoes are board lasted, slip lasted or combination lasted. A board lasted shoe is very stiff and has a piece of cardboard or fiber overlying the shank and sole (sometimes the shank is incorporated into the midsole or last) .  It is very effective for motion control (pronation) but can be uncomfortable for somebody who does not have this problem.  A slip lasted shoe is made like a slipper and is sewn up the middle.  It allows great amounts of flexibility, which is better for people with more rigid feet.  A combination lasted shoe has a board lasted heel and slip lasted front portion, giving you the best of both worlds.

When evaluating a shoe, you want to look at the shape of the last (or sole).   Bisecting the heel and drawing an imaginary line along the sole of the shoe determines the last shape.  This line should pass between the second and third metatarsal.  Drawing this imaginary line, you are looking for equal amounts of shoe to be on either side of this line. Shoes have either a straight or curved last.  The original idea of a curved last (banana shaped shoe) was to help with pronation.  A curved last puts more motion into the foot and may force the foot through mechanics that is not accustomed to. Most people should have a straight last shoe. 

The Upper (the sides and top of the shoe)

This is the part above the midsole that holds your foot on the sole. It is usually made of nylon, Gore-Tex or some other man made material. Pick something light and breathable.

The Heel Counter (the back of the upper)

This is part of the upper. A strong, deep heel counter with medial and lateral support is also important for motion control; lateral support especially for people who invert a great deal or when you’re going to place an orthotic in the shoe which inverts the foot a great deal.  The lateral counter provides the foot something to give resistance against.  This needs to extend at least to the base of the fifth metatarsal, otherwise it can affect the foot during propulsion. A deep heel pocket helps to limit the motion of the calcaneus and will also allow space for an orthotic. The heel counter should grip right above the calcaneus, hugging the Achilles tendon.

The Toe Box

The toe box should be generous enough to prevent crowding and pressure on the metatarsal heads.  The widest portion of the shoe should parallel a line bisecting the metatarsal heads.  Excessive pressure can result in bunions and/or hammertoes.  The shoe may soften and break down laterally, but it will not increase in length.

When measuring feet and determining shoe sizes, do it both sitting and standing, because the laxity of ligaments can become very evident, especially when the foot is weight bearing or you have the weight of a pack on your back.  If the person has greater than one size of splaying in both length and width when going from one position to the other, go for the bigger size.  Always use ball length rather than sole length. People usually buy smaller shoes because when you pronate, there is less volume in the mid foot and a smaller size shoe will feel better.

The Insole (the removable inner footbed)

This is the part of the shoe that most people remove to put in an orthotic. They have come a long way in construction and make a big difference in shoe fit. They are usually made of some type of foam or EVA material. Some of the newer ones are even dual density foam.

Well, if you made it through this, you are officially as nerdy as us. We’ll see you in the shoe isle…..

 We remain, The Gait guys….

horse: walk, trot, canter, gallop
man: walk, jog, run, sprint….very similar
….amble…..well that is another story……horse “ambling” gaits, a collection of several other smooth footfall patterns that may appear naturally in some individuals but which usually occur only in certain breeds, and often require special training…….as for humans? hummm. time for some homework

" target="_blank">Why I run......amazing video→

thanks Kyle and Jason and Newton…….this one is what it is really all about……. “in life we dont have it all figure out, there are key moments that change your life forever”.

So…..to close out the week…..we put aside anatomy, biomechanics, physics, neurology, orthopedics, research etc……we put it all aside……..and give you the big picture…..

“why i run”………don’t miss this one……it just might pull a tear from your eye……Thanks Kyle and Jason…….

Today’s post is a very nice follow up to the one earlier in the week entitled “Materials: do soft soles improve running shoes?”……which also commented on client perceptions of the footwear.  We hope the shoe and R&D companies are paying close attention to the work were are making available here. 

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Today…..

Perceiving is believing

What you think matters! Perception of shoe cushioning seems congruent with what you believe.  If you THINK the cushioned shoe will be softer, you will probably perceive it as so, even though there may be little to no change in ground reaction forces. Most studies show cushioned shoes actually INCREASE impact forces.

McCAW, STEVEN T.; HEIL, MARK E.; HAMILL, JOSEPH: The effect of comments about shoe construction on impact forces during walking

Medicine & Science in Sports & Exercise: July 2000 - Volume 32 - Issue 7 - pp 1258-1264

journal link:

http://journals.lww.com/acsm-msse/Abstract/2000/07000/The_effect_of_comments_about_shoe_construction_on.12.aspx

conclusions as quoted in their article:

“Footwear designers incorporate a variety of midsole materials and mechanical systems to cushion shock while controlling rearfoot motion. To market shoes, advertising copy and the claims of salespeople often extol the benefits of the materials and design incorporated in a shoe. This marketing strategy is common, as evident from a perusal of a fitness magazine, in spite of a paucity of unbiased biomechanical testing of the validity of many of these claims, and a lack of understanding of how such claims may influence the gait behavior of a purchaser of a pair of shoes.”

It is vital to understand their next research finding from this study,

“The results indicated the impact ground reaction force varied as a function of the advertising message. When subjects were informed that a particular surface provided additional cushioning, impact ground reaction force data were higher (121% of body weight) than when subjects were provided with a warning message (110% of body weight). The results were interpreted as suggestive of subjects moderating impact in accordance with the expected cushioning of the material. That is, subjects were less inclined to use a landing strategy that would reduce impact force if they had been told that cushioning would be provided by the surface material. The study raises the question of how subjects would respond if the cushioning characteristics of a shoe, rather than a landing surface, were altered, because a shoe represents a more personalized aspect of the foot/ground interface.”

From their study they referenced Robbins and Waked:

“Robbins and Waked (15) demonstrated that subjects may be deceived into accepting higher forces during landing if provided with misleading information regarding the energy absorbing characteristics of the landing. Because of research suggesting a possible cause of lower impact peaks in harder shoes to be an intrinsic avoidance mechanism (1), it may be theorized based on expectancy theory that influencing someone to believe that one shoe can absorb more energy than another may result in different ground reaction force values. Contrary and sometimes confusing findings in the literature emphasize the need for further study in the area of perception and energy absorption. The purpose of this study was, therefore, to determine the effect of investigator comments regarding shoe construction on the ground reaction force measured during walking.”

This is an excellent article that seems to suggest that there is far more to it than the engeneering that goes into the shoe. That marketing and consumer assumptions are a part of how a shoe is used and works. 

Very interesting !  We hightly recommend you purchase this article here…..

http://journals.lww.com/acsm-msse/Abstract/2000/07000/The_effect_of_comments_about_shoe_construction_on.12.aspx