From Traditional trainers to minimalism…… so, what is the “earth shoe” then ? Will the fad return ? Will we see running shoes go this far ? Afterall, we are at zero drop now ?

So, we all have seen the trend……. minimalism is here and it is not a fad, it is a trend and it is here to stay. It is here to stay because it is not a fad like this shoe above.  The Earth shoe has made 2 resurgences in the last 4 decades. We are likely to see another very soon since this minimalism trend has occurred. Make no mistake though, the minimalism is not a fad, it is a trend and it will be staying. 

So, what is wrong with this shoe ?

Minimalism will remain because we are finally restoring the normal rear foot : forefoot parameters to what we were born with. We were born with the rear and forefoot on the same plane, flat on the ground.  This even playing field, or at least a return to it for many shoe manufacturers, allows the anatomy (both bone and soft tissues such as muscles) to again operate in the fashion it was designed.  Sure the “running form” changes everyone is promoting is important. It is critical to get into good form. But unless the foot’s parts are normalized to the optimal mechanics we were born with even running form changes will not correct 100% of a person’s mechanical issues. 

The minimalism is allowing the rear foot to drop down to the same level of the forefoot, the same operating plane.  This necessitates length in the posterior compartment (calf and achillies mechanism) which will enable the anterior compartment (tibialis anterior and toe extensors) to see more function and thus gain more strength.  This plays well into our long standing theories that stretching of the calf, albeit sometimes necessary to a point, is not the answer for tightness in the calf…..rather putting the foot in a posture to enable the anterior compartment will earn length in the posterior compartment.  Here comes another mantra we use in our offices……. “Gain Anterior strength to achieve Posterior Length”.  Merely stretching the posterior compartment to gain length does not afford anterior strength.  So, it depends if you want a temporary bandaid or a long term fix.  We opt for the fix which is why it is a rarity that you ever hear from us “Mrs. Jones, you need to stretch your calf”.  Instead we teach the solution.

What else comes to mind about minimalism.  Well, again take the shoe above to give an extreme example of what dropping the heel will do.  It will shift your weight bearing posture posteriorly. Go ahead…..stand on the ball of your feet….. your body mass shifts forwards, your low back might arch if you do not have enough abdominals.  IF you then drop the heel you will feel your body posture shift backward and you will feel more glute and more abdominal and neutral pelvis-core posturing. You will also feel a more balanced weightbearing between the forefoot and rearfoot. This is good. These are just some of the things that minimialism does.  There is alot more.  But those are for another time.

In the meantime. The earth shoe. It drops you into rearfoot negative. The rearfoot is lower than your forefoot.  Remind you of anything ? Yup, walking in the sand. The heel sinks more if you load it first.  This will create a drastic change in length-tension relationships between the calf and anterior compartment. It will load the anterior ankle (mortise joint) and can really challenge the shin muscles.  Ever get shin splints or soreness the next day after a long beach walk ?  There is your reason.  So, the Earth Shoe. It is not natural. It puts your rearfoot and forefoot on two separate planes of operation. Or think of it this way…..it raises your forefoot onto a higher plane.  Walk around on your heels with the ball of your foot off the ground.  Feel your anterior muscles challenge ? You might even feel the posterior compartment stretch load a little. And we know that when you put a stretch through a loaded muscle the golgi tendon organ fires to inhibit that muscle….. yup, right when you are about to need it to push off.  Pretty messed up huh ?

If you want to see some messed up mechanics buy your favorite enemy some earth shoes. Look for the knees to hyperextend backwards a little, look for a bouncy vertical gait, look for toe gripping/hammer toe development among other things.  They can be a sneaky vengeful gift. 

Shawn and Ivo….. rediscovering the old groovy trends and hoping everyone stops at zero-drop.  Otherwise watch out for our vengence …   “V” is for Vendetta ! 

Stretching out Plantar Fasciitis→

Neuromechanics Weekly: Look to the hammy’s???

“These findings show that while we always consider the tightness of the gastrocnemius/soleus complex and the subsequent restricted ankle motion from this equinus, we also need to consider the role of the hamstrings,” said Jonathan Labovitz, DPM, lead author and associate professor at Western University of Health Sciences, Pomona, CA.

this article from Lower Extremity Review, concludes “After controlling for covariates, participants (86 of 210 feet) with hamstring tightness were 8.7 times as likely to experience plantar fasciitis (p < .0001) as participants without hamstring tightness. Patients with a BMI >35 were 2.4 times as likely as those with a BMI <35 to have plantar fasciitis.”

The question is why?

They go on to say “ If you can’t get dorsiflexion at your talo-crural joint, this often drives dorsiflexion at other joints and that is going to cause collapse of the longitudinal arch of the foot, loading the plantar fascia with increased tensile stress.”

So, loss of ankle rocker leads to increased midfoot pronation, which loads the plantar fascia. That sounds pretty logical to us. We are sure you are thinking a loss of hip extension may do the same thing. Correct. Or you may say ” The calves may be tight so the medial gastroc can invert the rearfoot to correct for too much midfoot pronation and the foot can be supinated"…and you would be correct again.

So why are the tight hammys driving the bus? Or are they?

We remember the hams are a 2 joint muscle, and with the foot in a closed chain position (ie, on the ground); they flex the thigh on the lower leg and tilt the pelvis posteriorly (ie reduce the lordosis). They are FLEXORS which are active from late swing phase, just prior to heelstrike (initial contact) and a little nudge just prior to toe off (preswing) to help extend the thigh. 

The tricep surae are FLEXORS and are supposed to be active from loading response till almost pre swing, with a burst of activity at heel lift (terminal stance). 

So they take turns, and are not firing (normally) at the same time (or maybe have a small overlap). Going from heel strike to heel strike, the hammys fire 1st.

So IF the two are related, it could be a neurological sequencing issue. How often does that happen? The literature says (and there aren’t many studies) that you can change the order of recruitment of motor units ( the nerve and the muscle fibers it innervates), but not (usually) individual muscles. So probably not.

OK, how about plan B?

The hams and tricep surae are all flexors, correct? What is the innervation to the hamstrings and tricep surae? Hmm….Hamstrings, mostly tibial branch of the sciatic nerve, short head of biceps femoris is the common peroneal: L5-S2. How about the tricep surae? Tibial nerve, mostly S1-S2. I think I see a trend here. Common neurological overlap of FLEXOR muscles.

So are the hams driving the bus? Probably not, but neither are the gastroc/ soleus. The FLEXORS are driving the bus, and excitation of that common neuronal pool is probably causing the tightness

Ivo and Shawn….Uber footgeeks of the web. Dicing and slicing through the literature so you don’t have to.

Proof that women are not unstable at the time of menstruation.

On the subject of proprioception, here is something we found interesting while on a quest for another article. 1st, we had found an article in the NY Times blog, talking about training considerations of women during their monthly cycle.

They state: “There may, however, still be reasons a woman to consider her period when planning training. A study published this year by scientists at the University of Melbourne in Australia, for instance, found that when women’s estrogen levels were at their highest, around the time of ovulation, they landed subtly differently while hopping than at other times of the month. Their feet splayed, the arch collapsing just a little bit more than it did when their estrogen levels were lower. The women also seemed, to a small degree, wobblier. “We contend that the changes in foot biomechanics may be due to the effects of estrogen on soft tissue and/or the brain,” said Adam Leigh Bryant, a senior lecturer at the University of Melbourne and lead author of the study.”

This says, in a nutshell, that women are not unstable around the time of menstruation (dispelling many common myths to the contrary) but rather, they are unstable around the time of their ovulation (proprioceptively speaking, of course). Women on monophasic contraceptives showed less variability (greater stability) and therefore may be more less injury prone.

Of course we pulled the study (abstract below). We found it interesting that it may actually be a neurological/cortical phenomenon, rather that muscle estrogen receptor based. What is the advantage of less proprioceptive awareness with increased estrogen levels? Maybe (in a bit of a stretch), it was for propagation of the species. If the women can’t get away, then they are more likely to be caught (or less likely to be able to run…)

The Gait Guys….Sifting through the literature and sometimes poking a little fun at it.

Ivo and Shawn.

http://www.ncbi.nlm.nih.gov/pubmed/20857138

Eur J Appl Physiol. 2011 Feb;111(2):245-52. Epub 2010 Sep 21.

Estrogen-induced effects on the neuro-mechanics of hopping in humans.

Bryant AL, Crossley KM, Bartold S, Hohmann E, Clark RA.

Source

Centre for Health, Exercise and Sports Medicine, School of Physiotherapy, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, VIC, 3010, Australia. albryant@unimelb.edu.au

Abstract

Estrogen receptors in skeletal muscle suggest a tissue-based mechanism for influencing neuromuscular control. This has important physiological implications for both eumenorrheic women with fluctuating estrogen levels and those with constant and attenuated estrogen levels, i.e., women using the monophasic oral contraceptive pill (MOCP). This study examined the effects of endogenous plasma estrogen levels on leg stiffness (K (LEG)) and foot center of pressure (COP) during hopping. Nineteen females (Age = 28.0 ± 4.2 years, Ht = 1.67 ± 0.07 m, Mass = 61.6 ± 6.8 kg) who had been using the MOCP for at least 12 months together with 19 matched, female, non-MOCP users (Age = 31.9 ± 7.3 years, Ht = 1.63 ± 0.05 m, Mass = 62.5 ± 5.9 kg) participated. Non-MOCP users were tested at the time of lowest (menstruation) and highest (≈ ovulation) estrogen whilst MOCP users were tested at Day 1 and Day 14 of their cycle. At each test session, K (LEG) (N m(-1) kg(-1)) and foot COP path length (mm) and path velocity (mm s(-1)) were determined from ground reaction force data as participants hopped at 2.2 Hz on a force plate. Statistical analysis revealed no significant (p < 0.05) differences for K (LEG). In contrast, significantly higher COP path length (30%) and COP path velocity (25%) were identified at ≈ ovulation compared to menstruation in the non-MOCP users. Whilst there was no evidence of an estrogen-induced effect on K (LEG); significantly elevated estrogen at ≈ ovulation presumably increased extensibility of connective tissue and/or diminished neuromuscular control. Consistent lower limb dynamics of MOCP users demands less reliance on acutely modified neuromuscular control strategies during dynamic tasks and may explain the lower rate of lower limb musculoskeletal injuries in this population compared to non-MOCP users.

“There may, however, still be reasons a woman to consider her period when planning training. A study published this year by scientists at the University of Melbourne in Australia, for instance, found that when women’s estrogen levels were at their highest, around the time of ovulation, they landed subtly differently while hopping than at other times of the month. Their feet splayed, the arch collapsing just a little bit more than it did when their estrogen levels were lower. The women also seemed, to a small degree, wobblier. “We contend that the changes in foot biomechanics may be due to the effects of estrogen on soft tissue and/or the brain,” said Adam Leigh Bryant, a senior lecturer at the University of Melbourne and lead author of the study.”

Last week an article popped up on Men’s Health online. It was an article written by McDougall called A Wild Workout for the Real World. The article was about this chap Erwan LeCorre and the system of natural movement that he created.  Here is a sampling video. Enjoy. 

http://www.menshealth.com/fitness/fitness-survive-wild

The Confusion of Shoe Science (Part 5 of 5): Narrowing the Gap Between Science, Manufacturer, Retail and Consumer

This is an important series of lectures / debate.  This event occurred on December 6th, 2011 at The Running Event which we also lectured at.  The result of this series of talks, which we will post 2-5 sequentially daily here on our blog, was an underground heated dialogue between some of the speakers. 

We have come to greatly respect Blaise Dubois for his vast wealth of knowledge and his unbiased standpoint. Blaise is a physicial therapist with worldwide respect for his knowledge and experience.  Unlike some of the other speakers you will hear in the coming days, he had no vested interest other than sharing the facts and myths in this field.  This is why we have enjoyed our growing relationship with Blaise, because we too have no vested interest with any company other than the truth. 

Watch these videos and learn, and make your own conclusions.  But, if you are a runner or shoe store owner or staff, you need to watch these and open your mind and consider that what you are being told by your shoe vendors might not always be the truth.  Educate yourself, ask the hard questions of your shoe vendors and companies and make your own conclusions. 

Shawn and Ivo  ……. bringing this stuff to you so you do not have to find it on your own.

Thinking about throwing away those old running shoes? Think again. A recent study looking at plantar pressures in new vs old shoes reveled that newer shoes had higher perssures, assumedly due to increased stiffness of the shoe.

This definitely is a fly in the ointment about changing your shoes every 500 miles and supports a slow break in for any shoe.

Ivo and Shawn. Yes, we are shoe geeks…even on a Sunday

The Confusion of Shoe Science (Part 4 of 5): Narrowing the Gap Between Science, Manufacturer, Retail and Consumer

This is an important series of lectures / debate.  This event occurred on December 6th, 2011 at The Running Event which we also lectured at.  The result of this series of talks, which we will post 2-5 sequentially daily here on our blog, was an underground heated dialogue between some of the speakers. 

* Here is the problem. Shoes are not designed around the extreme foot types at either end of the Bell Curve.  They are designed for the foot in a normative range. Simon says here that we can manipulate the shoe to determine of the foot can pronate or supinate.  That is what shoes have been doing all along ! This is what the dual density is used for. This is what the crash zone is used for, etc etc.  This was a pretty commercialized closing by Simon, he spent alot of time talking about Asics. There was little “narrowing of the gap” for us.

Watch these videos and learn, and make your own conclusions.  But, if you are a runner or shoe store owner or staff, you need to watch these and open your mind and consider that what you are being told by your shoe vendors might not always be the truth.  Educate yourself, ask the hard questions of your shoe vendors and companies and make your own conclusions. 

Shawn and Ivo  ……. bringing this stuff to you so you do not have to find it on your own.

The Sole Truth and Nothing but the Truth

Thicker soles mean more muscle activity. Nothing new here. We have posted on the fallacy of increased cushioning and decreased impact many times. Here is another supporting study.

Here are part of the results: “Compared to the barefoot condition, there is an increase in the magnitude of muscle contraction on wearing shoes, which further increases with thickening shoe soles.”

and the conclusion...“Footwear with increasing shoe sole thickness evokes a correspondingly stronger protective eversion response from the peroneus longus to counter the increasing moment at the ankle-subtalar joint complex following sudden foot inversion. Hence, fashion footwear with thicker sole is likely to increase the risk of lateral ligament injury of the ankle when such protective response is overwhelmed. Similarly, the clinicians need to be cautious regarding the amount of shoe raise that they could provide for patients with limb length discrepancy without any detrimental untoward side effects.”

We remember the peroneus longus attaches from the upper, lateral fibula, traveling down the fibular shaft, around the lateral malleolus and attaching to the base of the 1st  1st metatarsal and lateral cunieform. It fires from just prior to heel strike to terminal stance, assisting in eversion of the foot and cuboid,  locking the lateral column of the foot during supination, and plantar flexes the 1st ray (brings the medial tripod down to the ground). More sole = More activity = More potential for injury

more on peroneus here

The Gait Guys. Bringing you the science of shoes and the impact on gait, every day.

http://www.ncbi.nlm.nih.gov/pubmed/22017890

Foot Ankle Surg. 2011 Dec;17(4):218-23. Epub 2010 Sep 17.

The influence of shoe sole’s varying thickness on lower limb muscle activity.

Ramanathan AK, Parish EJ, Arnold GP, Drew TS, Wang W, Abboud RJ.

Source

Institute of Motion Analysis & Research, Department of Orthopaedic & Trauma Surgery, TORT Centre, Ninewells Hospital & Medical School, University of Dundee, Dundee, DD1 9SY, Scotland, UK.

Abstract

BACKGROUND:

The lateral ligament injury of the ankle is acknowledged to be the most common ankle injury sustained in sport. Increased peroneus longus muscle contraction in the shod population has already been documented. This study aimed to quantify the effect of shoe sole’s varying thickness on peroneus longus muscle activity.

METHODS:

Electromyographic recordings of the peroneus longus muscle activity following unanticipated inversion of the foot from 0° to 20° in a two-footplate tilting platform were collected from 38 healthy participants. The four test conditions were: barefoot, standard shoe, and shoes with 2.5 cm and 5 cm sole adaptation respectively.

RESULTS:

Compared to the barefoot condition, there is an increase in the magnitude of muscle contraction on wearing shoes, which further increases with thickening shoe soles. The peroneus longus was responding earlier in the shod conditions when compared to the barefoot, although the results were variable within the three shod conditions.

CONCLUSION:

Footwear with increasing shoe sole thickness evokes a correspondingly stronger protective eversion response from the peroneus longus to counter the increasing moment at the ankle-subtalar joint complex following sudden foot inversion. Hence, fashion footwear with thicker sole is likely to increase the risk of lateral ligament injury of the ankle when such protective response is overwhelmed. Similarly, the clinicians need to be cautious regarding the amount of shoe raise that they could provide for patients with limb length discrepancy without any detrimental untoward side effects.

Copyright © 2010. Published by Elsevier Ltd.

The Confusion of Shoe Science (Part 3 of 5): Narrowing the Gap Between Science, Manufacturer, Retail and Consumer

* note, if you rushed ahead and watched PART 3 on the IRRC youtube page,  you will now want to watch this critiqued version by Blaise Dubois. This is important that you watch this version so you can get a clearer truth and less of a commerical bias, in our opinion.

This is an important series of lectures / debate.  This event occurred on December 6th, 2011 at The Running Event which we also lectured at.  The result of this series of talks, which we will post 2-5 sequentially daily here on our blog, was an underground heated dialogue between some of the speakers. 

The Gait Guys have no vested interest with any company other than the truth. In our opinion Simon Bartold’s lecture here is very biased towards the company he works for, Asics.

Watch these videos and learn, and make your own conclusions.  But, if you are a runner or shoe store owner or staff, you need to watch these and open your mind and consider that what you are being told by your shoe vendors might not always be the truth.  Educate yourself, ask the hard questions of your shoe vendors and companies and make your own conclusions. 

* If you wish to watch this version without the important additions added by Blaise, you can go here and which Simon’s commercially biased lecture unabridged. click here

Shawn and Ivo  ……. bringing this stuff to you so you do not have to find it on your own.

The Confusion of Shoe Science (Part 2 of 5): Narrowing the Gap Between Science, Manufacturer, Retail and Consumer

This is an important series of lectures / debate.  This event occurred on December 6th, 2011 at The Running Event which we also lectured at.  The result of this series of talks, which we will post 2-5 sequentially daily here on our blog, was an underground heated dialogue between some of the speakers. 

We have come to greatly respect Blaise Dubois for his vast wealth of knowledge and his unbiased standpoint. Blaise is a physicial therapist with worldwide respect for his knowledge and experience.  Unlike some of the other speakers you will hear in the coming days, he had no vested interest other than sharing the facts and myths in this field.  This is why we have enjoyed our growing relationship with Blaise, because we too have no vested interest with any company other than the truth. 

Watch these videos and learn, and make your own conclusions.  But, if you are a runner or shoe store owner or staff, you need to watch these and open your mind and consider that what you are being told by your shoe vendors might not always be the truth.  Educate yourself, ask the hard questions of your shoe vendors and companies and make your own conclusions. 

Shawn and Ivo  ……. bringing this stuff to you so you do not have to find it on your own.

Boots make the Man (or the Woman)

If you had any doubts about shoes changing ground reaction forces (GRF’s), then read no further.GRF’s are one of the factors considered by some sources as being injurious.

Tennis shoes had the most ground reaction forces

Army boots came in a narrow second

Bare feet had the least forces by a significant amount

Incidently, the amount of the valgus in the knees on landing was not significantly different among the 3 cases.

Hmmm. We need to think before recommending a shoe.

Ivo and Shawn. The Gait Guys. Sifting through the literature so you don’t have to. Yes, we are still bald, middle aged and good looking….

J R Army Med Corps. 2011 Sep;157(3):218-21.

A kinematic and kinetic analysis of drop landings in military boots.

Oliver GD, Stone AJ, Booker JM, Plummer HA.

Abstract

OBJECTIVE:

The purpose of this study was to examine knee valgus in drop landings during three different footwear conditions and to examine the ground reaction forces exhibited during the drop landing in the three different footwear conditions.

METHODS:

Sixteen male and female Reserve Officer Training Corps (ROTC) university undergraduate cadets (21 +/- 3 yrs, 79 +/- 12 kg, and 172 +/- 10 cm) volunteered to participate in the study. Kinematic data were collected while participants performed drop landings in three conditions: bare feet, tennis shoes, and issued military boots.

RESULTS:

Significant differences among footwear for ground reaction forces (bare feet: 1646 +/- 359%, tennis shoe: 1880 +/- 379%, boot: 1833 +/- 438%; p < 0.05) were found, while there was no significant difference in knee valgus among footwear.

CONCLUSIONS:

Though footwear conditions did not affect knee valgus, they did affect ground reaction forces. Participants in this study had yet to receive any military training on how to land properly from a specified height. Further research should be completed to analyze the kinematics and kinetics of the lower extremity during different landing strategies implemented by trained military personnel in order to better understand injury mechanisms of drop landings in this population. It is likely that injury prevention landing techniques would be beneficial if these were employed by the military and not just in the sporting community.

Shoe News You Can Use

Pronation is dorsiflexion, eversion and abduction, It is a term usually used to refer to midfoot motion. It occurs as the friction of the heel with the ground causes the talus to slide anteriorly on the calcaneus, as it does so, it plantar flexes, adducts and everts. this motion causes a medial spin of the talus, which, in turn, causes an internal spin of the tibia (see above).

Pronation is a natural motion which  is one of the 4 shock absorbing mechanisms we have to attenuate force (pronation, ankle dorsiflexion,knee flexion and thigh flexion). Some pronation is necessary for normal gait. Over or under pronation appear linked to increased likelihood of injury. Of the 2, over pronation is the most treated (possibly wrongly so) and one intervention is motion control shoes.

Motion control shoes usually have a feature (medial posting, varus positioning, dual density midsoles, increased lateral flare, etc) which attenuates or delays pronation.

Along those lines, an in light of our latest series of posts, we thought you may find this study interesting. Results were as follows: “A one-tailed paired t-test indicated a statistically significant decrease in the total range of proximal tibial rotation when a motion control shoe was worn (mean difference 1.38°, 95% confidence interval 0.03 to 2.73, P=0.04).”

So, motion control shoes decreased motion about 1-1.5 degrees. The average amount of midfoot motion is 4-8 degrees. Our question to you is “Is that enough, or is that significant?”

We think so, especially in some cases. A few degrees can make all the difference. There appears a time and place for motion control shoes, but on our opinion, they are grossly over prescribed for problems that are usually able to be treated more conservatively.

The Gait Guys. Promoting Gait and Foot literacy…everywhere

Physiotherapy. 2011 Sep;97(3):250-5. Epub 2011 Feb 2.

Effect of motion control running shoes compared with neutral shoes on tibial rotation during running.

Rose A, Birch I, Kuisma R.

Abstract

OBJECTIVE: To determine whether a motion control running shoe reduces tibial rotation in the transverse plane during treadmill running.

DESIGN: An experimental study measuring tibial rotation in volunteer participants using a repeated measures design.

SETTING: Human Movement Laboratory, School of Health Professions, University of Brighton.

PARTICIPANTS: Twenty-four healthy participants were tested. The group comprised males and females with size 6, 7, 9 and 11 feet. The age range for participants was 19 to 31 years.

MAIN OUTCOME MEASURES: The total range of proximal tibial rotation was measured using the Codamotion 3-D Movement Analysis System.

RESULTS: A one-tailed paired t-test indicated a statistically significant decrease in the total range of proximal tibial rotation when a motion control shoe was worn (mean difference 1.38°, 95% confidence interval 0.03 to 2.73, P=0.04).

CONCLUSIONS: There is a difference in tibial rotation in the transverse plane between a motion control running shoe and a neutral running shoe. The results from this study have implications for the use of supportive running shoes as a form of injury prevention.

Copyright © 2010 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

The Confusion of Shoe Science (Part 1 of 5): Narrowing the Gap Between Science, Manufacturer, Retail and Consumer

This is an important series of lectures / debate.  This event occurred on December 6th, 2011 at The Running Event which we also lectured at.  The result of this series of talks, which we will post 2-5 sequentially daily here on our blog, was an underground heated dialogue between some of the speakers. 

We have come to greatly respect Blaise Dubois for his vast wealth of knowledge and his unbiased standpoint. Blaise is a physicial therapist with worldwide respect for his knowledge and experience.  Unlike some of the other speakers you will hear in the coming days, he had no vested interest other than sharing the facts and myths in this field.  This is why we have enjoyed our growing relationship with Blaise, because we too have no vested interest with any company other than the truth. 

Watch these videos and learn, and make your own conclusions.  But, if you are a runner or shoe store owner or staff, you need to watch these and open your mind and consider that what you are being told by your shoe vendors might not always be the truth.  Educate yourself, ask the hard questions of your shoe vendors and companies and make your own conclusions. 

Shawn and Ivo  ……. bringing this stuff to you so you do not have to find it on your own.

A beautiful and informative video on natural running by our friend Dr. Mark Cucuzzella.  If you run, you better watch this !  Thanks for including us in the credits at the end Doc !

Neuromechanics Weekly: Pain Matters

We know that joint swelling (and thus inflammation) inhibits the contraction of the muscle which crosses the joint from the landmark work of Iles and Stokes back in the late 80’s. Now here is a paper stating that pain does the same thing. 

This tells us that there is an axon collateral from the primary pain neuron (the “C” fiber) that somehow inhibits the alpha moto neuron, similar to a flexor reflex, as pictured. his is most likely through affecting the gamma moto neuron (which goes to the spindles) rather than the alpha motoneuron; so the “sensitivity” of the muscle is changed (remember, spindles detect length changes, golgi’s tension).

So what does this mean to us and gait? It tells us that pain will inhibit the activity (voluntary and involuntary) of the ability for one to use their muscles, especially those crossing the joint in questions. Be aware of inflammation (painful or non painful) or the painful joint, which can contribute to a compensation pattern.

Ivo and Shawn…The Gait Guys. Making your life less painful and more functional….

Muscle Nerve. 2000 Aug;23(8):1219-26.

Inhibition of motor unit firing during experimental muscle pain in humans.

Sohn MK, Graven-Nielsen T, Arendt-Nielsen L, Svensson P.

Source

Center for Sensory-Motor Interaction, Orofacial Pain Laboratory, Aalborg University, Denmark.

Abstract

Electromyographic activity was recorded in the masseter muscle to investigate whether the firing characteristics of single motor units (SMUs) were affected by muscle pain. Capsaicin was injected into the masseter to induce pain. The interspike interval (ISI) and recruitment threshold of SMUs were measured while subjects performed isometric contractions at 5, 7.5, 10, 15, and 20% of maximum voluntary contraction. All subjects were able to maintain a stable isometric force during pain, but the mean ISI was significantly increased without changing the recruitment threshold. In all the experimental conditions, the firing frequency increased with increasing force, and SMUs recruited at low force fired at higher rates for all force levels. These results suggest that acute stimulation of nociceptive muscle afferents inhibits SMU activity without changing recruitment order in the homonymous muscle.

Copyright 2000 John Wiley & Sons, Inc.

Sorry for the late post, folks…We both had pretty crazy days at our clinics…

Yup, you saw it here 1st. We couldn’t believe it either. Look what we found in the Harvard archives.

Sport féminin : saut sur échasses. Korean women on stilts jumping hurdles in a chase, for fun. Advert for Liebig’s Extract of Meat Company. 1904. Via Harvard U.

What does meat extract have to do with women on stilts, jumping hurdles? We could use some help on this one. Anyone have any suggestions?

The Gait Guys. Not on stilts, but teetering while jumping hurdles sometimes….

A case of severe mechanical gait challenges.

This is a unique case. This is a complicated case, there is so much going on. If your eye is getting good at this gait analysis stuff you will know that just from the first pass this gait is very troubled.

This young middle distance runner who came to see us with complaints of chronic anterior and posterior shin splints. This is unusual because usually only one of the lower limb compartments are strained, either the anterior (tibialis anterior mostly) or the posterior compartment (tibialis posterior mostly). Admittedly this is not a fast runner but they love to run none the less, so you do what you can to help.

Please watch this video again and note the following:

1. crossing over of the knees at the midline (this indicates a scissored gait / circumductory motion of the limbs)
2. slightly wider based gait compared to knee postioning but neutral compared to hip spacing
3. client starts heavily on the outer edge of the feet and moves medially
4. client over strides (step length is increased) which is particularly evident when they are walking towards the camera
5. early bunion formation and troubles engaging the big toe during stance phase
6. the knees / patella also appear medially positioned in an environment of a neutral foot progression angle
7. if you look carefully you can see that they rear foot immediately moves into a valgus posturing (this is rearfoot pronation) and they are also pronating into the forefoot heavily. Interestingly they have decent arch height.

Wow ! So much going on ! This is a gait from hell in some respects. So, what is driving so much of the terrible gait mechanics ? The answer is a congenital loss of ankle rocker (dorsiflexion) bilaterally. This client can barely squat because the ankles just do not dorsiflex. There was clear osseous lock at barely 90 degrees.

Lets break each one down.

1. Crossing over of the knees at the midline (this indicates a scissored gait / circumductory motion of the limbs). * This is occuring due to some genu valgum of the knees (slightly “knock-knee”). When the knees are valgum they are at risk for brushing together during gait. The client has no choice but to circumduct the limbs to avoid this behavior. Unfortunately they cannot abduct the thighs far enough during many of the gait cycles and so a “Scissored” appearance occurs where the thighs brush and cross over in appearance.
2. Slightly wider based gait compared to knee positioning but neutral compared to hip spacing. * This is closely related to our answer in #1. Valgus knees will widen the foot spacing side to side because the feet are not under the knee joints. Then couple this with the necessity to circumduct to avoid knees from contacting and the foot posturing is that of an even wider based gait. This can also occur from many hip problems. However as in this case with a congenital loss of ankle rocker, the client uses more foot pronation to progress the tibia over the talus (allowing the tibia to get past 90degrees) and allow them to move forward. This added pronation does magnify and likely progress the knee valgum but there are few other options for this client. This is often a destructive vicious cycle with few good outcomes decades down the road.
3. Client starts heavily on the outer edge of the feet and moves medially. *This may be to avoid the immediate rear foot pronation that is seen here.
4. Client over strides (step length is increased) which is particularly evident when they are walking towards the camera. * This may be a conscious attempt to lengthen the shortened stride that occurs because of the limited ankle dorsiflexion ranges. It appears at many moments however to be a result of the extra effort to circumduct the legs sufficiently. A longer stride does play into #3 above, a larger stride usually leads to a heavier lateral heel strike but it also means that the rearfoot pronation will be more aggressive, this is a negative resultant outcome.
5. Early bunion formation and troubles engaging the big toe during stance phase. *We are not surprised here. Whenever pronation is excessive the first metatarsal (medial foot tripod) is unstable and this changes the mechanics of the hallux muscles to pull towards the 5th metatarsal anchor generating the bunion. Look at the origin and insertion of the adductor hallucis muscle particularly the transverse head, if the 1st MET is anchored the 5th MET is pulled to the 1st and the transverse arch is formed. However, if the 1st MET is unstable and the 5th is the only anchor, the adductor hallucis will pull the toe laterally and form a bunion and hallux valgus and compromise the transverse arch. (particularly look at the left big toe at the :09 to :11 second mark, the big toe and first MET are clearly not anchored to the ground).
6. The knees / patella also appear medially positioned in an environment of a neutral foot progression angle. * Answers for #1-#5 clearly will medial patellar deviation and drive patellar tracking problems.
7. If you look carefully you can see that they rear foot immediately moves into a valgus posturing (this is rearfoot pronation) and they are also pronating into the forefoot heavily. Interestingly they have decent arch height, but remember, that does not mean that pronation is not occurring. * This is a result of the loss of ankle rocker mechanics. If they start pronation early at the rear foot it will drive more pronation. When pronation is driven excessively the arch can drop, and with more arch height drop the tibial will pitch forward past the magical 90 degree mark and allow forward motion to occur.

So, how can they run with all this going on ? Well, the answer is quite simple. They avoid most of these issues as best they can. How you ask ? Forefoot strike; they run avoiding heel strike and midfoot strike. By staying on the forefoot all of these rear and midfoot mechanical limitations as well as ankle rocker loss can be avoided by remaining on the forefoot. This makes distance running difficult but anything below the two mile mark is tolerable and the 100-800 distances are probably best suited for their feet. Incidentally they enjoy the 400 the best, no wonder. Also, moving at increased speed will necessitate a forward lean, and a forward lean makes the tibia progression over the talus easier taking out some of the ankle rocker limitations.

This is a foot type, with complications, that is really beyond much of what anyone can do conservatively. We would even argue that surgery is not an option, just a change in activity choice. This is simply a client that should not run beyond distances where they can stay on the forefoot. The foot, ankle and lower limb mechanics just suffer far to much from having to compensate (as discussed in #1-7) to enable pain and problem free running with anything other than forefoot loading. This means that walking is going to be difficult and problematic, as you can see from this video above.

Our only solution in this case ? ……… utilizing a rocker based footwear. Easy Spirit Get UP and Go (link) was our recommendation and it worked very well for this client for walking. Here is a link to this shoe and pictures of the huge forefoot rocker that helps (somewhat) to dampen the mid-forefoot rocker issues but there is not much that can be done for the rear foot rocker issues as discussed. If you use an orthotic to block the rearfoot valgus motion and rearfoot pronation you will pass more challenges to the midfoot-arch and forefoot. Sadly.

This was a very tough case. Getting every aspect of the case in your head during an evaluation is sometimes a challenge. Sometimes you need to see them a 2nd or 3rd time to digest it all. But be patient with yourself, it takes time to get decent at this stuff. This is a perfect case for “getting a feeling and flow” of the persons gait, at their speed. A case evaluation like this on a treadmill or via video analysis can make things tougher because the treadmill can change the dynamics (did you read our Treadmill article in last months Triathlete magazine ? It was linked on the blog 2 weeks ago) and make the client move at its speed and not their speed inhibiting and promoting different mechanics. There are times for a treadmill and times to avoid them. This is an art, in time you will know when to use and when not to use.

Happy Monday Gait Gang………. welcome to The Gaits of Hell !

Shawn and Ivo ……….two gnarly lookin dudes with pitchforks and a toothy grin.

see the previous  blog post for the Lower Body Drivers and our dialogue. 

Just scroll down to the next blog post.

Rolling patterns and their use in body assessment.

First a brief review from yesterday where we talked about the stabilizing function of the diaphragm possibly being an etiological factor in spinal disorders.  Yesterday we included a link to an abstract by the great Dr. P. Kolar.  It considered the correlation between the dynamics of the diaphragm in posture and chronic spinal disorders.  In review of that paper what they found seemed to indicate that poor diaphragm positioning, posturing and control correlated well in their sampling of chronic low back pain clients. The study found smaller diaphragm movements and a higher diaphragm positioning/posturing.  The study found maximum changes in the rib (costal) intervals and middle areas of the diaphragm which asks one to consider the absolute critical importance of thoracic mobility. Extension, lateral flexion and rotation are frequently reduced in chronic back pain clients but we find it rampant in many clients and athletes.  We also find and encourage you to look for, assess, and normalize your clients abdominal oblique, transverse abdominus and rectus abdominus control.  Failure to properly and adequately anchor the lower rib cage to the pelvis via the abdominal wall (the whole wall, circumferentially around the entire torso to the spine) will result in asymmetrical breathing patterns.  And abnormal breathing patterns lead to abnormal spine motion and mobility.

Yesterday we spoke about the need to assess, and if necessary treat, anything that impairs the diaphragm, breathing patterns, thoracic spine mobility and rib cage movement and flexibility.  Rolling patterns as seen above, and here is the Rolling Pattern for Upper Body Drivers (link), are helpful in determining some loss of coordination of the upper or lower body drivers, impaired thoracic spine mobility as well as loss of symmetrical abdominal skill and strength.  Remember, impairment of a primitive movement pattern like rolling is important to be aware of.  The last thing you want to do is drive your training or treatments therapies and rehab efforts into an asymmetrical pattern. These rolling patterns are first developed as a child to learn to turn over. It is a precursor to pressing up the torso like in a push up, which is of course a precursor to crawling, then cruising and then walking.

  Just like yesterday, we come full circle !  From breathing and the diaphragm to rolling and gait…… it is all connected.  Any faulty strategy or pattern driven into the body, even breathing, can impair gait.  And remember, because with gait we have to attach anti-phasic arm swinging with leg swinging. Anything that disturbs this anti-phasic patterning, such as low back pain or loss of thoracic mobility, will drive contralateral arm-leg swing to phasic patterning.

These are nice, simple assessments.  Hope you enjoyed another window into what we do every day when dealing with athletes, patients and runners.  It is all a part of restoring the symmetrical function to a body.

Shawn and Ivo ……. Rock and Rollers.

The Roll of Breathing and Diaphragm Control in Gait, Running and Human Locomotion

In this video you will see many great things. This video of Rickson Gracie is a testament to free fluid movement and body control.  Great athletes do not just practice one thing.  There is some great demonstrations of breathing and diaphragm control at the 3 minute mark, and we will try to parlay this nicely into today’s brief discussion on the Diaphragm.

Abnormal stabilizing function of the diaphragm may be one etiological factor in spinal disorders.  Today we have included a link to an abstract by the great and brilliant Dr. P. Kolar who we have studied under.  It considers the correlation between the dynamics of the diaphragm in posture and chronic spinal disorders.  What they found seemed to indicate that poor diaphragm positioning, posturing and control correlated well in their sampling of chronic low back pain clients. The study found smaller diaphragm movements and a higher diaphragm positioning/posturing.  The study found maximum changes in the rib (costal) intervals and middle areas of the diaphragm which asks one to consider the absolute critical importance of thoracic mobility. Extension, lateral flexion and rotation are frequently reduced in chronic back pain clients but we find it rampant in many clients and athletes.  We also find and encourage you to look for, assess, and normalize your clients abdominal oblique, transverse abdominus and rectus abdominus control.  Failure to properly and adequately anchor the lower rib cage to the pelvis via the abdominal wall (the whole wall, circumferentially around the entire torso to the spine) will result in asymmetrical breathing patterns.  And abnormal breathing patterns lead to abnormal spine motion and mobility. We frequently have to treat and instruct proper breathing patterns to help normalize lateral and posterior rib cage expansion and decent in athletes and clients, particularly those with low back issues but that is not an exclusive group to this problem. Tomorrow we will show you some simple but great videos showing rolling patterns and we will want you to think back to today’s blog post here on how loss of thoracic mobility in extension, rotation and lateral bend as well as loss of symmetrical abdominal skill and strength can impair a primitive movement pattern like rolling. This is a pattern that is first developed as a child to learn to turn over. It is a precursor to pressing up the torso like in a push up, which is of course a precursor to crawling, then cruising and then walking.

See, we were finally able to come full circle !  From breathing and the diaphragm to gait…… it is all connected.  Any faulty strategy or pattern driven into the body, even breathing, can impair gait.  Because with gait we have to attach anti-phasic arm swinging with leg swinging. Anything that disturbs this anti-phasic patterning, such as low back pain, will drive contralateral arm-leg swing to phasic patterning. Don’t think this is important to athletes and humans ? Well, you must have missed our 2 part blog series on Arm Swing.  We provide those links here. Part 1 link and Part 2 link. 

If you are an athlete, coach, or in the medical movement assessment or gait analysis field……heck, if you study the human body at all and you are not looking at or into arm swing you are not doing what we are doing. And you are missing the bigger boat. So many “gait specialists” and “gait analysis” programs are not even capturing the arm swing let alone looking at it and discovering its critical importance. Did you miss our dialogue on frozen shoulder and impaired contralateral hip dysfunction ?  If you look for it, which many in the therapy world are not, you will see why we treat that opposite lower limb.  Maybe the rest of the folks around the world will catch on in time.  We are slowly getting there, we now have readership in 23 countries, and growing.  If only we had more time, the apocalypse of December 21, 2012 is coming on fast !

The article also found maximal changes in the middle diaphragm areas which suggests looking at the psoas, quadratus lumborum and crus because of their fascial blending into the diaphragm from below.  Thus, investigation of many muscles from below must also be a part of your assessment or training.  But we will save this discussion for another blog post.

We hope you can see that after a year of blog posts (over 500) that you can begin to see the method of our obvious madness.  That being that everything is important for human gait. Remember, we will blend this blog post into the roll assessments you will see on tomorrows post.  So ya’ll come back now……. ya hear ? 

In closing, it is blog posts like this one that we always hope will go viral on the internet. Especially because it has links to two previous articles we wrote on arm swing which we feel are so very important and commonly overlooked.  And we have more arm swing stuff to share, we just need more time.  Consider linking this article to your website, sending it to friends in the fields we discussed. This information is important. It is why we take the time every day to write and share our 40+ years of clinical experience for free. Because the world needs to know this stuff so more people can be helped all over the world.  Consider sharing this with someone or linking it to your Facebook page or website or slap it up on someones forum to create dialogue. Thanks.

The leg bone is connected to the thigh bone…. as the song goes…….

Shawn and Ivo

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here is Kolar’s abstract……

J Orthop Sports Phys Ther. 2011 Dec 21. [Epub ahead of print]

Postural Function of the Diaphragm in Persons With and Without Chronic Low Back Pain.

Kolar P, Sulc J, Kyncl M, Sanda J, Cakrt O, Andel R, Kumagai K, Kobesova A.

Abstract

OBJECTIVES:To examine the function of the diaphragm during postural limb activities in patients with chronic low back pain and healthy controls.

BACKGROUND: Abnormal stabilizing function of the diaphragm may be one etiological factor in spinal disorders, but a study designed specifically to test the dynamics of the diaphragm in chronic spinal disorders is lacking.

METHODS: Eighteen patients with chronic low back pain due to chronic overloading, ascertained via clinical assessment and MRI examination, and 29 healthy subjects were examined. Both groups presented with normal pulmonary function test results. A dynamic MRI system and specialized spirometric readings with subjects in the supine position were used. Measurements during tidal breathing (TB), isometric flexion of the upper or lower extremities against external resistance together with TB (LETB and UETB) were performed. Standard pulmonary function tests (PFT) including respiratory muscles drive (PImax and PEmax) were also assessed.

RESULTS: Using multivariate analysis of covariance, smaller diaphragm excursions (DEs) and higher diaphragm position were found in the patient group (p’s<.05) during the UETB and LETB conditions. Maximum changes were found in costal and middle points of the diaphragm. In one-way analysis of covariance, a steeper slope in the middle-posterior diaphragm in the patient group was found both in the UETB and LETB conditions (p´s<0.05).

CONCLUSION: Patients with chronic low back pain appear to have both abnormal position and a steeper slope of the diaphragm, which may contribute to the etiology of the disorder. J Orthop Sports Phys Ther, Epub 21 December 2011. doi:10.2519/jospt.2012.3830.