Bone marrow lesions in runners.

"More than half of the lesions (bone marrow edema) (58%; 26/45) fluctuated during the season, with new lesions occurring (20%; 9/45) and old lesions disappearing (22%; 10/45)."

Stuff happens to your bones during a marathon, or on that long weekend training run. Make sure you give yourself time to recover adequately before you pound out that next run.
The incidental finding of bone marrow edema (BME) on MRI in professional runners is not well understood. Bone takes on load, as it should. In this study, it is suggested that many asymptomatic athletes show BME lesions, many of which will come and go with training. It is most like proper and ample recovery that allows athletes to heal and not let these lesions turn into greater stress responses, or stress fractures. It is when the load comes too often, to long, heavy and hard that things might mount.

Sixteen athletes (13 men and 3 women; mean age, 22.9 ± 2.7 years) were recruited from the Dutch National Committee middle-distance and long-distance running selection. All athletes had been injury free for the year before the study. Magnetic resonance imaging scans were obtained before the start of the season and at the end of the season.

14 of the 16 athletes had BME lesions before the start of the season (45 BME lesions in total). Most BME lesions (69%; 31/45) were located in the ankle joint and foot. More than half of the lesions (58%; 26/45) fluctuated during the season, with new lesions occurring (20%; 9/45) and old lesions disappearing (22%; 10/45). The few clinical complaints that occurred throughout the season were not related to the presence of BME lesions.

Am J Sports Med. 2014 May;42(5):1242-6. doi: 10.1177/0363546514521990. Epub 2014 Feb 20.
Bone marrow edema lesions in the professional runner.
Kornaat PR1, Van de Velde SK.

Pod 144: Grounded running, Glute fatigue & Stress Fractures

Topics: Grounded running, Glute fatigue, Stress Fractures, Duty Factor, Ankle stiffness & Gait and Concussions

Keywords: gait, gait analysis, gait problems, running, ankle, band, concussions, fatigue, fracture, gait, glutes, grounded, gait guys, glute medius, problems, stiffness, stress, syndrome, time under tension

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Interested in our stuff ? Want to buy some of our lectures or our National Shoe Fit program? Click here ( or and you will come to our websites. In the tabs, you will find tabs for STORE, SEMINARS, BOOK etc. We also lecture every 3rd Wednesday of the month on We have an extensive catalogued library of our courses there, you can take them any time for a nominal fee (~$20).

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Hip muscle response to a fatiguing run in females with iliotibial band syndrome.
Brown AM1, Zifchock RA2, Lenhoff M3, Song J4, Hillstrom HJ3.
Hum Mov Sci. 2019 Feb 8;64:181-190. doi: 10.1016/j.humov.2019.02.002. [Epub ahead of print]

Balance and Gait Alternations Observed More than 2 Weeks after Concussion: A Systematic Review and Meta-analysis.
Wood TA1, Hsieh KL1, An R1, Ballard RA2, Sonoff JJ1.
Am J Phys Med Rehabil. 2019 Feb 5. doi: 10.1097/PHM.0000000000001152. [Epub ahead of print]

Does Running Faster Put You at Greater Risk of a Stress Fracture?
New research finds that speed might not cause as much strain on the shins as we thought
By Hailey Middlebrook
Feb 12, 2019

Fast Running Does Not Contribute More to Cumulative Load than Slow Running\
Hunter, Jessica G.1; Garcia, Gina L.1; Shim, Jae Kun1,2,3; Miller, Ross H.1,2
Medicine & Science in Sports & Exercise: January 25, 2019

Grounded running Reduces Musculoskeletal Loading.
Med Sci Sports Exerc. 2018 Nov 21
Bonnaerens S1, Fiers P1, Galle S1, Aerts P1,2, Frederick EC3, Kaneko Y4, Derave W1, De Clercq D1.

Duty factor:
duty-factor. The duration of a gait cycle where each foot is on the ground

Ankle intrinsic stiffness changes with postural sway
PouyaAmiri, Robert E.Kearney

Podcast 87: Podcast 87: The Kenyan's Running Brain & "The" Anterior Compartment.

Plus, Some unknown facts about going minimalism and barefoot. We POUND anterior compartment strength today gang ! Hope you enjoy !

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Show notes:

On high heels and short muscles: A multiscale model for sarcomere loss in the gastrocnemius muscle

The Brain Needs Oxygen

Maintained cerebral oxygenation during maximal self-paced exercise in elite Kenyan runners.
J Appl Physiol (1985). 2014 Nov 20:jap.00909.2014. doi: 10.1152/japplphysiol.00909.2014. [Epub ahead of print]

The texting lane in China

Dialogue on endurance training,
NeuroRehabilitation. 2006;21(1):43-50.

Effects of dorsiflexor endurance exercises on foot drop secondary to multiple sclerosis.  Mount J1, Dacko S.

APOS Therapy
we were asked out opinion on this

Foot instrinsic dialogue
Motor Control. 2014 Jul 15. [Epub ahead of print]

Quantifying the Contributions of a Flexor Digitorum Brevis Muscle on Postural Stability.
Okai LA1, Kohn AF.

There are many factors in adults that impair gait. It is not all biomechanical. This is part of our ongoing dialogue on the aging population and why gait impairments and falls are so prevalent.
Acta Bioeng Biomech. 2014;16(1):3-9.
Differences in gait pattern between the elderly and the young during level walking under low illumination.
Choi JS, Kang DW, Shin YH, Tack GR.

Podcast 78: Step Width Gait, Training Asymmetries & more

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Today’s Show notes:

24-year-old woman missing entire cerebellum exemplifies the amazing power of brain plasticity

Brain scans reveal ‘gray matter’ differences in media multitaskers

Who are we: Ivo talk a bit about yourself and your educational history and what is your website ?
Shawn… the same
and……lets keep each interesting but to just a few minutes
Effect of step width manipulation on tibial stress during running
Does Limited Internal Femoral Rotation Increase Peak Anterior Cruciate Ligament Strain During a Simulated Pivot Landing?
Quadriceps Muscle Function After Exercise in Men and Women With a History of Anterior Cruciate Ligament Reconstruction
Steppage gait ? Or just a runway model ?  Take the thinking farther.
Today we have a short blog post for you. You may take the topic simply on the surface or cogitate over it and find some deeper epiphanies from the well of knowledge we have tried to present here on our blog for the past 4+ years.  
It is clear that in this video that the model has a consciously driven steppage gait. Meaning, she is lifting her limb/foot via exaggerated hip flexion and knee flexion to clear the foot.  This is often seen unilaterally in a foot drop case where the client has a neurologic lesion that for one reason or another has impaired the client’s ability to extend the toes or dorsiflex the ankle sufficiently to clear the foot (so they do not drag toes and trip/fall).  
But, why is she doing this steppage gait ? It is highly unlikely that she has bilateral lesions.  Sure, she was asked to walk this way by her mentor but again, take it further.  Is there a factor making this gait necessary regardless of the coaching ? 
Obviously the answer is yes or we wouldn’t be doing a blog post on this topic.  She is wearing ridiculously high heels. This is forcing her into an extreme plantarflexed foot and ankle posture. IF she were to swing her leg normally during the swing phase she would drive the foot and ankle into dorsiflexion (a normal gait event) and the long pointed heel would be made more prominent as it was driven forward and downward. This would surely catch on the ground, immediately driving the foot into sudden violent forefoot loading and pitch her into a forward fall.  Yes, you have seen this on the run way videos on youtube, and yes we know you laughed too ! You see, when wearing heels this high, one must deploy a certain degree of steppage gait to clear the heel because ankle plantarflexion is fraught with the risk we just discussed above, the heel is too prominent and will catch. How much steppage (knee flexion and hip flexion to clear the foot) is necessary ? Well, to a large degree it depends on how much of a heel is present.  If you are wearing a small heeled shoe, lets say 1 inch, then a small steppage is necessary.
None the less, there is a bigger problem lurking and brewing underneath when heels are a regular occurrence. Slowly and gradually the disuse of the anterior compartment muscles (Extensor dig., Ext. hallucis, peroneus tertius, tibialis anterior) will weaken and the posterior compartment will shorten respectively. IF left too long, it will result in tightness (yes, there is a difference between tightness and shortness, one is a neurlogical protective mechanism, the other is a more permanent change.) We have said this many times here and in our videos, much of posterior compartment problems (ie achilles tendonitis, Sever’s, Hagglunds etc) are related to a degree of anterior compartment weakness, skill deficits or endurance challenges.  Wearing high heels often will often, but not always, increase this risk. 
If you are an athlete, but someone who wears high heels often, you may have to do extra work to keep your anterior compartment competent on several levels.  Eccentric strength is just as important as concentric in this region. Remember, many gait problems come on slowly, a slow simmering smoldering fire. And remember this last point about heeled shoes, your forefoot is always being loaded initially in ankle plantarflexion, this is not normal and in time this will have a cost in many people.  
One last thing. We are not necessarily talking about dress shoes, although they are a greater culprit.  Many running shoes still have accentuated rear foot stack heights where the heel will be many millimeters above the plane of the forefoot.  Do not discount these shoes as a possible contributor of your problem, remember, physiological adaptation takes time to express into a biomechanical symptom creating problem, and it may take quite some time to resolve your compensations and adaptations.
PS: drive that “cross over gait” lady.  Fools.
Shawn and Ivo
the gait guys

Podcast 32: "Shorts"- Stress Fracture Buddies

Today we have a 4 minute short clinical story on a case we saw in the recent weeks. We have searched the medical literature and have not found a study on what we attempted, but we hope that one of our listeners will have found one or had similar experiences and be willing to share their story or a client’s story.

This is a story of a high school middle distance runner who cut her toe, and ended up developing a stress fracture in her metatarsal.  And … . what we attempted to offer immediate change, some theories as to how it worked and how we saved her season (we hope).

Enjoy our short story. 

Imagine, think, ponder, explore and experiment.  Sometimes, you might be surprised what you can come up with, even when it is as simple as something as reaching for a roll of tape.

The Gait Guys


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Gait Guys, can I wear my racing flats during regular weekly base runs ?

Perhaps the better question is “should you wear your racing flats for regular base building runs ?"  Most injuries are based on a volume of impact miles across anatomy structures that are not appropriately protected or which have been encouraged into biomechanically challenged positions because of surrounding weakness or functional asymmetry.

In previous blog posts we have talked about the theory that more EVA foam is not always better and supported these ideas with research.  However, the pendulum can swing to the opposite as well. It is also plausible that a tipping point of less foam also increases risk because of a lack of shock attenuation.  The results of the study below demonstrated significant differences in peak pressure, maximum force, and contact area between the two shoe conditions of racing flat and regular training shoes (see study for specifics). There was a significantly higher maximum force measured in the lateral midfoot in the racing flats while an increased maximum force was observed beneath the rearfoot in the training shoe, 

What the study did not go into was the foot type and the running form from what we could tell. Heck, it is even possible that the small "n” of the study could have included a bolus of cross over runners with forefoot varus for all we know. the study did not delve that deep. We have all learned that often it is not what you do but how you do it and additionally, although not entirely pertinent here, that what we see is often not the problem (translation: just because the peak pressures measured high in an area does not necessarily mean that the adjacent anatomical structure to the peak pressure will suffer the impact and trauma of said pressures. This is a dynamic load sharing organism, where things break down is rarely where the problem exists)

Bottom line from our standpoint, and this does not hold true for everyone but it is a fairly safe statement, if your foot type is not pristine and your running form could stand some perfecting then perhaps running flats for anything than race day is not the most sane and cerebral decision.  This may be especially true if you are milking some subtle injuries or asymmetries that speak to you from time to time on a run.  But to each his own.  Human’s are inherently risk takers and subject to cognitive dissonance, especially when things are going well. And who knows, runners may fall even deeper into this profile for all we know.

Here is the study for your perusal. 

If you want to get better at this game of assessment, shoe fitting and foot type matching you might want to consider our National Shoe Fit Program.  Email us at if you want us to send you some information on our program.

Shawn and Ivo, The Gait Guys

Differences in plantar loading between training shoes and racing flats at a self-selected running speed.

 Wiegerinck JI et al.  Gait Posture. 2009 Apr;29(3):514-9. Epub 2009 Jan 14.

Summarized Abstract:

The purpose of this study was to examine the difference in plantar loading between two different running shoe types. We hypothesized that a higher maximum force, peak pressure, and contact area would exist beneath the entire foot while running in a racing flat when compared to a training shoe. Peak pressure, maximum force, and contact area beneath eight different anatomical regions of the foot as well as beneath the total foot were obtained. The results of this study demonstrated a significant difference between training shoes and racing flats in terms of peak pressure, maximum force, and contact area. The significant differences measured between the two shoes can be of importance when examining the influence of shoe type on the occurrence of stress fractures in runners.