We’ve got an angle….. The Progression Angle

1st of a non sequential series

The progression angle is the angle to foot makes with the ground at initial contact of gait to loading response, and it is often carried through the gait cycle to toe off (see left image above). It is something we often look at to see how a patient may be compensating. It often represents how forces are traveling through the foot (see right image above).

The normal line of force through the foot during a gait cycle should begin at the lateral aspect of the heel, travel up the lateral column of the foot, across the metatarsal heads from the 5th to the 1st, and then through the hallux (see L part of right picture above.

We remember that the foot strikes the ground in a supinated posture, then pronates from initial contact through the middle of midstance (to provide shock absorption and initiate medial spin of the lower extremity: see picture bottom left); the foot should then supinate, to make the foot into a rigid lever, with this being initiated by the opposite limb going into swing and externally rotating the stance phase lower extremity (se picture bottom right)

The progression angle is determined by many factors, both anatomical and functional, and is often a blend of the 2.

Anatomical factors include:

• subtalar joint positioning
• tibial torsion
• femoral torsion
• acetabular dysplasia

and functional causes can include:

• compensation for a hallux limitus or rigidus
• weak glutes (of course we wouldn’t leave our favorite muscle out)
• loss of ankle rocker
• over or under pronation
• and the list goes on….

Next time we begin breaking this down into bite sized chunks to aid digestion.

Ivo and Shawn. Bald. Good Looking. Middle Aged. Definitive Foot and Gait Geeks : )

The Gluteus Maximus: Part 2. More talk on gluteal function & its place in the gait and running cycle.

The gluteus maximus controls:

Flexion / Extension: The Sagittal Plane
- the rate and extent of limb flexion at term swing: this is eccentrically controlled
- hip extension: this is concentrically controlled
- hip flexion rate during loading response (eccentric at foot loading): this will help to control the vertical loading response as the body mass loads the limb there must be enough eccentric strength of the glute maximus to control-stop this loading so that hip extension can occur. This will indirectly assist in control some of knee flexion.

Rotation:
- external rotation of the limb: this is concentrically controlled
- assists in controlling the rate of internal rotation: this is eccentrically controlled

Pelvic Posturing:

- controls rate of Anterior Pelvic Tilt (APT): this is eccentrically controlled (this is relative hip extension as discussed in Part 1 last week)

- assists in Posterior Pelvic Tilt (PPT): this is concentrically driven

- controls sacroiliac joint mobility through FORCE CLOSURE (force closure is a compression of the joint surfaces by the contraction of muscles that cross the joint)

Divisions:

- the sacral division of the gluteus maximus is mostly a pure sagittal plane driver at the hip joint
- the coccygeal division is more of an adductor and internal rotator at the hip joint
- the iliac division is more of an abductor and external rotator at the hip joint

The gluteus maximus also has some fascial attachments into the posterior aspect of the TFL-ITBand. Remember, this TFL-ITB complex is an internal rotator of the limb in the gait cycle. You will recall that internal rotation is a precursor to hip extension. The hip must first, and adequately, internally rotate in the gait cycle before hip extension can occur. This means that for correct and complete gluteus maximus contraction to occur in the second half of the stance phase we must have adequate internal hip rotation. Without it, all of the things we talked about last week in our glut maximus blog post cannot occur properly. Now, back to our attachment disucssion of the gluteus maximus to the ITB-TFL mechanism. This attachment allows the gluteus maximus to produce posterior tension on the ITB-TFL mechanism so that it can be anchored to provide it’s internal rotation function on the limb. So, here we have a powerful hip extensor and external rotator providing assisted effects on an internal rotator of the limb. Isn’t the body a beautiful and amazing thing ! (Well it is. But if you will recall from the detailed layout above that the gluteus maximus in the eccentric phase of contraction functions to control the rate of internal hip rotation you will not be surprised or enlightened. Rather you will enjoy the brilliance of how an anchoring muscle is eccentrically giving up length while an agonist muscle is concentrically taking up length). The gluteus maximus-TFL relationship….. it is beautiful teamwork in helping, not exclusively of course, control limb rotation during loading responses.

Next time you see a client’s knee drift too far inwards during a lunge, or walking or running we hope this whole discussion will spring a light bulb moment for you. You must look at the complex function above in controlling the limb during pronation and supination. Merely inserting an orthotic is not going to fix a proximal deficiency, it could modulate it however. But wouldn’t you want to fix it ? Who wants an orthotic if you don’t need one ? Some people do, don’t get us wrong, but many do not. And then some just need them temporarily to gain the awareness and skill of posturing and function and once that is achieved the device and be weaned.

Just some more functional anatomy talk on a Monday morning…….from us, The Gait Guys

Shawn & Ivo

Gait and Foot pain in a 30 year runner. A possible Forefoot varus.

Hi Gait Guys:

I could use some help. I’ve been running/cycling for 30 years. Three years ago, I had surgery on my left knee that realigned my patella (lateral release.) Until recently, I lived in custom orthotics and motion control shoes. I’ve been reading chi-running and natural running and bought a pair of shoes for which I’m transitioning a little a day. My left foot is the problem: it severly overpronates and I have a neuroma. I’ve been walking barefoot and in five-fingers for a while and my feet a definitely getting much better. The natural running style feels much better on my ankles,knees and hips, which used to hurt a lot. Also, cycling hurts only when I get off my bike, my knee is killing me for a while.

My left forefront seems to move too much even with this new style of walking/running. I’m wondering if I have forefront varus that could be helped with a wedge. My real problem is that I currently live in Las Cruces, NM, where there is no running store and no experts on this stuff. Most podiatrists do the same, generic thing for all patients. Is there a little wedge I could try without having it inserted into a custom orthotic? Is there a place to go to analyze my gait/running that would be worth my time and expense to visit? Any advice would be gratefully received.

Thanks for your time, …. AT

_____________________________________

Thanks for the note AT.

We are glad that the natural style running is helping. remember to go slowly and follow the rules of Skill, Endurance, Strength as you progress into less supportive shoes.

The forefoot motion you are sensing MAY indeed be a forefoot varus; we would need to see and examine your foot to know for sure. The fact that you have had a neuroma and needed a lateral release are suspect for a forefoot varus.  With that 1st metatarsal head (the medial tripod) unstable and allowing more forefoot pronation your control of internal rotation of that limb is going to be difficult and drag patellar tracking off line. If it is a rigid deformity, it may never totally be gone, though you may be able to increase the range of motion of your foot sufficiently to compensate elsewhere. We have attached a photo of a prefabricated forefoot varus post (note its thickness on the outside edge and tapering as it moves inwards to the pre-fab it is attached to. It is a wedge.). In our in-house labs we make them custom to the client to get perfect control. We make them out of thermo-rubber-infused cork so we can grind them down as clients earn better ability to anchor the metatarsal tripod with intrinsic muscle strength through our specific exercise programs. It is also used for Rothbart Foot types which has some similarities to a forefoot varus. Make sure you do not have a Rothbart variant. We did a blog post on Rothbart many years ago. Search for in the search box from our archives.

Getting a thorough evaluation is paramount. We are not aware of any gait labs in Las Cruces, but Jaqueline Perry’s Pathokinesiology lab is in Rancho Los Amigos (click here for more info). Dr Waerlop is located about 70 miles west of Denver and Dr Allen is in the Chicago suburbs. Only after an evaluation, could exercise suggestions or an orthotic or other device recommendation could be made.

Thanks for your inquiry

Ivo and Shawn

Redoing your gait analysis?

Gait Guys:

How often do you need to get a gait analysis done when buying new runners? Started running one year ago and bought my first “real” pair of runners last spring. I have a ‘neutral’ foot or gait. Do I need to get it done now again when buying new ones or should I just go with the neutral runner gain? Does it change much over time with all that mileage?

Name Removed

Our Response:
Your running style will evolve (for better or worse) as you evolve as a runner. If you have had an adequate gait analysis initially, you should probably have a new one done every 6-12 months, depending on your training (style and mileage) and what your ultimate goals may be, especially if you are working at improving your running gait (which we hope you are!).

Ivo and Shawn

READY

Great Gait: You don’t see this that often

Great gait brought to our attention by one our readers; one his questions was how he had such great “kick back” traveling at the speed he was traveling at. 

 

Here is an efficient gait:  note he mid foot strikes (you may need to watch it a few times to see it) close to under body and does not over stride; he has great hip extension, and a forward lean at the ankles; even arm swing (note elbows do not go forward of and wrists do not go behind body). It all adds up!

So what causes such great hip extension? Largely 2 factors: forward momentum and glute (all 3; max, med and min) activation. From the last post and EMG studies, we know the glute max contracts at initial contact (foot stance) through loading response (beginning of mid support) and then again at toe off to give a last “burst”; the gluteus medius and minimus contract during most of stance phase. initially to initiate internal rotation of the femur (a requisite for hip extension);  the former to keep the pelvis level and assist in extension and external rotation during the last half of stance phase to assist in supination and creating a rigid lever to push off of. This is, of course, assisted by the opposite leg in swing phase.

Forward lean and momentum move the axis of rotation of the hip behind the center of gravity, assisting the glute max to extend and prepare the lower limb for the bust at push off. The stance limb, now in external rotation, makes it easier to access the sacral (especially) and iliac fibers of the glute max and the posterior fibers of the gluteus medius.

What a orchestration of biomechanics resulting here, in a symphony of beautiful movement.

The Gait Guys. Bringing you great gait, when available…..

A little something for our triathletes today on Friday Follies.

:-)

S & I (thx Les)

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Gait: When is the last time you used the swear words “closed kinetic chain” ? How well do you understand your Gluteus Maximus ?

These are just some fragmented, early morning, mental ramblings about the genius of the body. We are sure to follow up with more glute talk in time.

When the foot is engaged with the ground one of the major functions of the gluteus maximus is to draw the pelvis into posterior rotation (with some assistance of some other regional muscles of course). The pelvis is extending on the femur through the hip joint axis. If the foot is off the ground one would call this hip extension. But when the foot is on the ground, it is still hip extension, however our mental reference must change. This motion we have described, when the foot has purchase on the ground, is what happens when we return upwards from a squatted position (see ! it is still hip extension). You may find it a brain twister to look at the qluteus maximus also as a rotator of the pelvis away from your foot progression direction. Meaning, we think of the gluteus maximus also as an external rotation generator but when the foot is ground engaged contraction of the G. Max spins our pelvis (and connected torso) away.

Go ahead, stand on your right foot and contract your glute maximus. Which way does your body rotate ?

So, when contracted, if the right foot is on the ground the body pelvis-torso will spin to the left.

So, how do we use our glutes to help us move forward ?

Well, this is a complicated chain of events and this was not the purpose of our ramblings today. This muscle does not work in isolation. Might we just say that there is an opposite swing leg moving forward into flexion which helps to redirect that spin into a sagital progression. Go ahead, stand on that right foot again, contract the glute maximus and note the left rotation, but now add the left forward hip flexion placing the left foot into forward progression. Do you feel that torque and compression through the right hip, core and spine ? Do you have enough core strength to not prostitute the pelvic neutral posturing ? Did you drop into an anterior pelvis tilt (APT) ? Go ahead now, add the anti-phasic motion of contralateral arm swing just to add some more complex rotation to the picture. Are bells and whistles going off about some of your clients problems ? You might want to go back and re-read our work on Arm-Leg swing now. (click here). We plan to build on these concepts in the very near future ….. keep up with us, be ready !

There was alot going on here in what we just did. More on this another day, time to go put this gait stuff to our Friday patients. That is right, we just don’t talk about this stuff, we live it. Remember, unless your patients, clients and athletes wheeled themselves into your facility …… they walked in via the gait cycle. Know your stuff.

Have a great weekend peeps

Shawn & Ivo

“Learn a clean motor skill slowly, add endurance to that slow clean skill, add strength to that skill. Rinse and repeat.
Layering progressive skills and eventual speed to the prior skill achievements … until, like any high end movement endeavor, the task is unconsciously competent. Skipping any step in this logical neurophysiologically based ladder will result in a compensation pattern.”

—

The Gait Guys

Shawn & Ivo

“Form is dictated by Function.”

—

Excerpts from, “Building the Elite Efficient Injury free Athlete”. The topic at this years ITCCCA lecture.

It’s been said “Form follows Function” , to be clear……Form is dictated by Function.

For example, If you do not have good ankle rocker function your Form will:

1- not be optimal
2- require compensation / cheating
3- change, be limited, and prevent desirable Form
(Inefficiency + increased workload = eventual injury or system failure)

Your Form can only be as good as the Functioning of your physical parts.
If you or your athlete has bad Form….. Spending weeks on “running FORM clinics” or training hard to improve a loss of Form may only force new compensations. The solution to better “Form” is often sitting right in front of you in the form of biomechanical dysfunction. When you see bad Form you should ask yourself if that person lacks the functional parts to give you good Form. What you see in someone’s Form are their capabilities with the parts they have that work.

Mind you, some athletes or patients have all normal functioning parts available to them and all they need is Skill coaching or first level skill rehabilitation exercises … the first part of S.E.S. (*Skill, Endurance, Strength). Just always be on the look out for bad function.

Said another way, forcing what you think is good Form will quite often not work on someone with limitations; It will only develop further strength into a compensation pattern that you do not want. Instead, do the necessary initial work to resolve the function limitation so that you can begin to engrain skill Form patterns.

An elite and efficient athlete is one who:
1- has the parts ( sport is matched for body type),
2- presents with no dysfunction … . thus clean FORM,
3- understands that “more is not always better”
4- and has a coach, trainer or medical professional that can teach progressing levels of S.E.S. into that individual.

From this years lecture on “Building the Elite Efficient Injury free Athlete” presented January 14th at the ITCCCA (Illinois Track & Cross Country Coaches Association. This was a standing room only event. We look forward to presenting what we learn in 2012 at next years event. Thanks to all those who endured 2 hours sitting in the stairwells, on the floors and in the seats. Good luck this season everyone !

Shawn, Ivo & Coach Chris Korfist

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Imagine a World Without Free Knowledge

For well over a year now, we have spent thousands of hours building the most honest and reputable free online gait blog that we are aware of. We wish to continue this process and share our years of hard fought knowledge with you. We have a new project that will take us to the next level. We have begun the long arduous process of starting WikiGait, another free gait related website. 

Right now, the U.S. Congress is considering legislation that could fatally damage the free and open Internet. Blogs and websites like ours (Wikipedia (english) is blacked out today and thousands of other sites are as well) are at risk by our current government. For 24 hours, to raise awareness, we are refraining from posting and sharing our free information to make a stand with others. Contact your representatives to take a stand.

Educate yourself here (click). SOPA PIPA

Watch this girl walk. What is the most striking feature of her gait?

Is it the genu valgus? Is it her progression angle (or lack of?) Her Left sided increased arm swing? Her body shift to the left in Left stance phase?

We would like to discuss her progression angle. We remember that the progression angle is the angle the foot makes with the ground at heel strike and through stance phase (another way of describing it is, Are your feet turned out or turned in?). It is determined by many factors (forefoot position, subtalar joint angle, tibial abnormalities, femoral torsions, etc). In this case it is highly suspect that it is due to subtalar varum and internal tibial torsion, at least from what we can see and what we now without the advantages of an exam and clinical information.  Lets now make this assumption and talk about it from this angle.

Tibial torsion is due to the development of the tibial shaft. It begins in utero, where most of us have tibial varum (due to intrauterine positioning), usually Left sided more than right (because most babies are carried on their back on the Left side of the mother and the Left leg overlies the Right in an externally rotated and abducted position.

At birth, we usually have a 5 degree toe in due to a 30 degree angle between the talar dome and head, which slowly decreases to approximately 18 degrees as we grow into adulthood, leaving us with a 4 degree toe out (still a fairly narrow progression angle). Meanwhile, the tibial plateau and malleoli are parallel at birth and the distal tibia “untwists” externally as we age (at a rate of about 1-1.5 degrees per year) till it reaches an ideal of 22 degrees in adulthood.

Over rotation of the distal tibia (relative to the proximal) results in external tibial torsion with a “toe out” or as it is referred to as, increased progression angle. Under rotation results in internal tibial torsion, or a “toe in”, also referred to as a decreased progression angle.

Some sources say that the development of the talus (angle between the dome and head) is largely responsible for foot position and progression angle. We think that careful measurement (looking at the transmalleolar angle, a topic for another post) reveals which it is, and in our experience, it is usually a combination of both (ie tibial torsion and talar development).

This video is an excellent clinical example of an in toed gait, a negative progression angle.

Ivo and Shawn…The Gait Guys….Yes, we are torsioned (or twisted as some may argue)….straightening out the facts so you don’t have to.

More constructive dialogue on The Cross Over Gait: Q & A Session with a Mid-Distance Coach.

Dear Dr. Allen,

I attended your sessions yesterday at the ITCCCA Clinic, which I appreciated very much.  I am a retired middle/long distance runner who is now getting into coaching.  I have always been fascinated by this kind of research and spotting warnings [things presented at the conference this year ] before they become injuries.  I think that the attention you are bringing to video analysis, form, and SES is the most significant change happening in the sport of running.  Applying this analysis to young runners will help countless numbers of them, both by identifying weaknesses to strengthen and by alerting coaches to an athlete’s propensity for certain overuse injuries. 

As your work gains much deserved attention, I do have a concern with your approach to the “cross-over gait."  I spoke with you briefly about it yesterday, and I have been thinking about it since then.  From my experience and amateur research, it seems as though a distance runner does well to strike both feet along a single line.  Here is a little of my reasoning:

Distance running is largely about efficiency.  While a sprinter gets more power and speed by pushing in a zig zag pattern from foot to foot, that does not mean it is an efficient action.  A distance runner does want some power in his/her stride, but cannot afford to waste any energy like a sprinter can.  I would argue that the difference between a sprinter’s ideal stride and a distance runner’s ideal stride should reflect this. 

It seems logical that a runner’s most efficient push-off point is directly beneath his/her center of gravity.  If we strike the ground to the left or right of this point, some energy goes into sideways motion or adjusting for the asymmetrical force with more glute action.  To your point, this off-center stepping pattern almost certainly yields more power than a straight-line pattern, as the best short-sprinters all use it.  I found this video of Carl Lewis’ beautiful stride demonstrating your point.

However, if you look at the best distance runners in the world, and even middle distance runners, you’ll see much more "cross-over."  The other two videos I list below aren’t great, because they’re in real time, but you can still discern the in-line foot strike of most of the athletes.  These runners may be getting less power out of their glutes, but they’re taking advantage of the gluteus maximus’ natural design to rotate the pelvis forward efficiently.  For most of the race, I’m not convinced that altering that pattern would be productive.
 
I am far less knowledgeable than you in physiology and biomechanics, and I have not performed the necessary research to substantively contradict you, but I write to request that you investigate this issue further.  I may also have misunderstood the nature of your form adjustment work with middle- and long-distance runners; kicking at the end of the race or surging in the middle could very well take more of a sprinter’s form.  The general stride of a distance runner, however, is likely specific to the particular demands of the race and the body’s aerobic limitations. 

I think that coaches should be very careful to adjust a runner’s natural stride unless there is significant evidence supporting the change.  When the evidence is clear, I like that your approach is as deep as possible: finding the root cause of the weakness and working on it gradually.  I fully support your efforts to prevent injuries in this way.  I urge you to continue expanding the body of research and striving to improve the experiences of budding runners.

Thank you for considering my observations.  Please feel free to contact me anytime.

A.

______________________________

Our response:

Dear A.:

I appreciate your inquiry in the most cordial manner, the coaching world is blessed to have attentive and curious coaches like yourself. Great insight comes from great questions like this. 
I certainly do appreciate your concerns.  But your personal opinion needs some backing. I fully respect and understand your thoughts and although they are well thought out, there is nothing i have found in the literature to support it.  Mind you, there is not alot to support mine either however results do have a voice and when we make these changes, even in our mid distance runners, their injuries resolve and do not recur and their times drop.  So, there is some strength to the crossover correction it seems. More research would be nice but no one is doing it so we must base our thinking on some logic as laid out below.

Keep in mind efficiency comes with using each muscle optimally and quite often in
"line running” (crossing over) the gluteus medius and foot do not work correctly. Look at the terrible foot function in the video above. Please watch and read our 2 part series on the blog on Lauren Fleshman(links below). She is fraught with injuries and her hip and foot biomechanics are terrible as we point out in both of those blog posts.  Improving her muscle efficency in using them correctly will improve her overall kinetic chain efficiency, certainly make her less injury prone, and probably make her faster. 
As for putting one’s foot under their body mass,  I challenge your thought merely because when you are on one foot your center of mass is shifted over to the stance leg not directly under your sacrum (watch my 2 part series on youtube “hip biomechanics”,  here I explain the accepted biophysics of the kinetic limb).
The foot should be under the knee and hip, where the body mass has shifted in the single leg position.  The only person who will not shift their mass is one who doesn’t use their gluteus medius to draw the mass over the hip (again, it is in the hip mechanics videos) and that person will likely have hip problems in time because the compressive load on the femoral head is excessively abnormal plus they are often fraught with trochanteric bursitis and chronic ITB issues (let alone knee and foot issues).

Please digest what I have said here and lets keep a constructive and productive dialogue going, nothing I said here was meant to upset you, merely to try to give you my stance.
I am never afraid to have my theories challenged. I am humble enough to know I do not know everything and admit when I am wrong. I want to learn and get smarter so I can help more athletes and coaches become better.  So, if you can refute my dialogue above, particularly with science and research, I am happy to continue this learning experience for us both.  But please watch the videos I have mentioned first so we can base our discussions on solid functional anatomy and biomechanics (save us time, so we can get down to a good dialogue).
So, to this point, although i see your logic, I respectfully must disagree from sheer fact on anatomy, physics of body mass shift, and biomechanics.  I think you will find the 2 brief lectures on hip biomechanics exciting and helpful.
Remember, the swing leg is a pendulum, the most effective pendulum is one that never shifts its center of pivot (energy change),  the cross over gait shifts with every step. A centrated joint is one that pivots freely allowing the attached musculature to function as they were designed.
 I look forward to future constructive dialogue. I would like our relationship to be an asset for us both.

Below are the videos, in logical order, to support my response.

http://thegaitguys.tumblr.com/post/10239421449/dr-shawn-allen-discusses-gait-biomechanics-again

http://thegaitguys.tumblr.com/post/10400372557/in-this-part-2-installment-of-applied-hip-gait

http://thegaitguys.tumblr.com/post/13158702554/the-cross-over-gait-in-a-professional-runner

http://thegaitguys.tumblr.com/post/13298030775/how-a-really-fast-runner-could-potentially-be

http://thegaitguys.tumblr.com/post/13205227823/gait-video-analysis-olympian-carl-lewis-carl

Then of course there is the 3 part crossover gait series we did on August 24th & 25th (you can access our archives by clicking on the clock in the upper right corner of the blog page).

respectfully……. and fully appreciating your passion
shawn and ivo……. The Gait Guys

Foot Strength: Some Clinical Q & A.→

A Few question (and answers) about Foot Problems, from our Blog.

Dr. Ivo Waerlop and Dr. Shawn Allen,

I have had the pleasure of reading much of the content of your website and I have gained many valuable insights into the fascinating world of gait. I have a number of questions that I would love to get your perspective on though. First question: What exercises or techniques do you use to strengthen the intrinsic foot musculature? I gleaned that you are not particularly fond of flexor dominant exercises like towel scrunches so how do you functionally improve the strength, muscular balance and neuromuscular control over those little muscles? Second question: What strategies do you use when treating runners with plantar fasciitis? Would you move them into a less supportive or minimalist shoe or would you bump them up temporarily into a stiffer shoe or use a rigid orthotic?

I would like to also take the time to thank you guys for posting volumes of valuable information on your website. I have found that your website has a remarkable amount of solid, scientifically based information on topics that typically are rife with misinformation when discussed on other websites. Keep up the excellent work and I greatly look forwards to hearing your response to my questions.

Thanks,

JD

____________________

The Gait Guys Response:

JD:

Thanks for the support and the kudos. In answer to your inquiries:

“First question: What exercises or techniques do you use to strengthen the intrinsic foot musculature? I gleaned that you are not particularly fond of flexor dominant exercises like towel scrunches so how do you functionally improve the strength, muscular balance and neuromuscular control over those little muscles?”

Exercises are prescribed very specific to muscle weakness. There are no “swiss army knife” exercises. Each case is on an individual basis, based on physical exam and muscle testing. For the most part, there are really no bad exercises just bad choices for a specific case and poor execution (although one can easily find on YouTube a plethora of ridiculous examples of foolishness worthy of only The Darwin Award).

The small, intrinsic muscles of the foot have many functions, but flexion of the distal toes is not one of them (this is all afforded via the long flexors, FDL). Proprioception from the feet is very important and information from these muscles, as well as the articulations they traverse, provide the brain with much information about the environment, as well as the landscape they are traversing. Increasing proprioception from the feet (through gradual introduction of more minimalistic footwear and going barefoot) is as paramount, if not more important, as increasing strength. Skill, endurance, strength (S.E.S.) in that order (larger diameter, medium diameter and smaller diameter neurons respectively) is the rule for progressing exercise.    S.E.S. is an abbreviation we coined, but it is based purely on neurophysiology principles …  all of our information is science based. You will find no ‘internet forum’ assumptions here, as  you have so accurately gleaned. As for an example of some of our exercises, we are currently trying to find time to create some new videos of our current exercise protocols. As we mentioned however, it is a difficult projected since each case has different needs and differing orders of protocol. None the less, here is an “oldie but a goodie” from two years ago. Click here.

“Second question: What strategies do you use when treating runners with plantar fasciitis? Would you move them into a less supportive or minimalist shoe or would you bump them up temporarily into a stiffer shoe or use a rigid orthotic?”

A: The causes of plantar fascitis are multifactorial, but I think we all agree that overpronation of the rearfoot, midfoot, forefoot (or a combination) all play a frequent role. Following that assumption as a possible cause, the question is, What is causing the overpronation? Is it due to muscular incompetence? Is it due to loss of ankle rocker? Is it due to a loss of hip extension? Is it due to….. (fill in the blank).

The treatment depends on the etiology. As we just eluded, the cause is not always a foot issue, there can be top-down kinetic chain causes. Progressing them to more minimalistic footwear is a great idea (provided they have earned their right to be in it and have muscular competency and appropriate foot structure). The problem is that not everyone does have the necessary structure to drop into minimalism, some never and some need help with a logical progression.  Modalities like acupuncture, ultrasound and EMS, to reduce inflammation certainly help in pain management and can expedite the healing process. At times, if the case calls for it, using an orthotic to temporarily give them the mechanics they do not have, and relieve some of the tension of the fascia is appropriate. Sometimes the orthotic makes things worse (too much support, not enough support). Sometimes, albeit rare, the orthotic is suspect as the causal mechanism.  The root cause needs to be identified and then the appropriate therapy can be initiated.

We get questions like these all the time. They are great questions but they are often fraught with so many open ended subsequent questions and parameters that we often feel our answers are never good enough.  But, if solving things like plantar fascitis were easy in every case, we would not see clients in our practices who arrive with a bag of orthotics, a long  history of therapy, and multiple failed interventions. There are no easy answers or magic bullets. If there were, there would be no need for The Gait Guys.

Providing answers to difficult questions.

Ivo and Shawn

Robotic Gait Retraining→

People who have had a stroke and have difficulty walking often develop improved gaits when they add robotic assistance systems to conventional rehabilitation. A study funded by the Italian Ministry of Health and Santa Lucia Foundation compared the walks of 48 severely impaired stroke survivors. Half the group received conventional rehabilitation and the other half received conventional rehab plus robotic gait training. The study, published in Stroke: Journal of the American Heart Association, showed the added robotic gait training worked for people with severe impairments, but did not significantly help patients with higher mobility.

The robotic devices are electromechanical platforms attached to a patient’s feet. A physical therapist sets progressive bearing weights and walking paces and measures how the patient is doing.

So, the question is WHY? The simple answer is that we are much smarter than a computer or device. The brain makes millions of calculations per second to perform the concert we call gait. A computer cannot approximate all the variables; only the ones that are programmed. The folks with more mobility (less morbidity) were “smarter” and more than likely, the computer slowed them down. The less fortunate ones needed more help.

The Gait Guys: sifting through the literature and bringing you the highlights.

Yup. We thought we had seen it all. Make sure to wear your evening formal neoprene. Coming soon: Underwater Gait Analysis.

Have a great Friday

Ivo and Shawn

photo credit: xcitefun.net

Foot Landing Mechanics→

Foot Landing Mechanics, Part 1 of 2

This dialogue is likely going to open up a storm of controversy and dialogue,  …  good !

In a very recent article in LER (Lower Extremity Review) Katie Bell wrote a nice article about foot “Orthotics and Landing Mechanics”.  Her article, and the research she referenced, suggests foot orthoses can affect frontal and transverse plane motion in proximal joints during landing from a jump. It was postulated from the research that orthotics could therefore help reduce the risk of anterior cruciate ligament injury, particularly in females.

In the May issue of the Journal of Applied Biomechanics, it was determined that gender differences as well as foot orthotics affect frontal plane hip motion during landing after a vertical jump. This is really nothing new or mindblowing. Heck, putting a pebble in someone’s shoe will change their landing and gait mechanics, but it is nice to see more talk in the research. Any observant and educated clinician can see that from a vertical jump, if the client does not have enough gluteal function to slow the internal spin of the limb (the glute is a powerful external rotator and thus also a powerful eccentric controller of internal rotation) that the knee will valgus medially. Furthermore, if the foot is not strong and stable, the downward weight will collapse (to varying degrees) the arch and thus also drag the knee medial. Thus, it is critical to discuss both components of knee stability, meniscal issues and ACL issues.  Any study omitting observations of gluteal function and only commenting on the effect and merits of the orthotic to control the knee is only telling half the story. Admittedly, research articles can look at isolated issues like this study did if it pleases them, but it is our mission not to let tunnel visioned biases enter into things. Tunnel vision leads to assumptions that some problems have simple solutions. Our clients get evaluated through the entire kinetic chain when looking at foot and knee issues. Heck, even arm swing and opposite leg swing impact the function of the stance phase knee (look at the mechanics behind the Abductory Twist for example or read our blog posts from early December on arm swing impacting lower limb mechanics).

We are not dismissing these research findings however, yes orthotics can help reduce risk at the ACL …  IN SOME CLIENTS, but it could enable risk in others if the correction at the foot is not the proper intervention. What if the entire risk scenario is from a dysfunctional hip ? Now you have changed the foot’s dynamic compensation for the hip dysfunction. Couldn’t that increase ACL risk ? You bet it can. Thankfully, as we read on, the LER article quoted Walter Jenkins PT, DHS, associate professor and chair of ECU’s Department of Physical Therapy. “Dysfunctional hip motion is commonly observed in patients with knee pathology.” It was nice to see that, sadly we felt the articles angle was to mediate the dysfunctional hip motion via correction at the bottom. We all should be reminded that the organism must be evaluated and thus treated as a whole.

Modifying dysfunctional hip motion locally, if there are local issues, can reduce knee risk and may modify the necessity or degree of intervention at the foot level. So, landing mechanics are about the foot, the hip and the knee mechanics pending the mechanical forces from those other two joints above and below. Merely adding an orthotic is going to change the landing mechanics but, as we mentioned earlier, putting a pebble in someone’s shoe is going to change their foot dynamics and how they load, so is a pebble a reasonable answer too ? The question is are they the mechanics you want for your client ? Are the foot changes with an orthotic locally prostituting the normal hip mechanics ? Orthotics are not the Holy Grail. In some cases they are the Devil’s pitchfork. It takes a very educated and skilled practitioner to know the difference.

The Journal of Applied Biomechanics researchers analyzed the 3D motion of the lower extremities in 36 study participants (18 women, 18 men) during a vertical jump with and without prefabricated foot orthoses. In the women researchers found significantly less hip adduction with foot orthoses compared with no orthoses (p< .05). The men showed no differences between foot orthoses conditions. So, does this mean that the women need orthotics ? Or does it mean that their Q angle is a participant ? Does the study necessarily mean that the answer to these ladies issues is an orthotic ? Or does it mean that they could need more hip stability and loading skills to dampen internal limb rotation and valgus knee drift ? The article (thankfully) does suggest that the apparent gender-specific proximal reactions to foot orthoses during landing may be related to kinematic landing strategies which is a good observation, but do not think that orthoses are the take away answer from this article.

The study also showed things we have talked about previously, that being that men actually land in knee varus and use hip adduction and knee valgus as a strategy to accelerate during the jump after the deceleration phase of landing. Where as women tend to land more valgus and but seem to be more challenged to control this force.  But for an article to suggest that “A foot orthotic may be a simple solution—and quicker than neuromuscular retraining—to control motion.” is a scary conclusion. They go on to say “Ultimately, orthoses may be an excellent adjunct to a neuromuscular training program.” we agree with in part.

Nothing is more valuable than a limb that can support and control itself with optimal neuromuscular function. If you do not have it, take time away from risky sport challenges until you have achieved it. Do not take a short cut and depend on an external device, unless of course the client has a fixed anatomical compensation or issues (ie. forefoot varus) OR you are using it as a training aid, to TEMPORARILY offer mechanics that the client does not have, working toward helping them to eventually get them. In those cases, a device is often helpful and recommended, but IT IS IMPERATIVE  to retrain neuromuscular protective reflexes and function.

We are going to do a Part 2 on this very important topic this weekend. If you are in a sport where you are jumping and landing you absolutely need to read Part 2. We will be offering up a hopeful epiphany for you on why so many people sprain their ankles. It is a landing mechanics problem…… not discussed anywhere else in the research or on the web….. until now !

We are The Gait Guys …. two guys who always finding themselves standing outside some strange box everybody is talking about.

Have a good Friday everyone !

Shawn and Ivo

A 30 second workout has similar results as a 90 minute one ?→

McMaster University (Canada) studies on the effectiveness of high intensity interval workouts. 

Sprint Results Set the Stage

The 2005 study and others (links provided above), published in the Journal of Applied Physiology and , showed that three to seven all-out sprints on a stationary bicycle (250% of VO2 max), 30-seconds each, with four-minute rest periods, six times over two weeks, are as effective as 90 to 120 minutes of cycling at moderate intensity (65% of VO2 max) six times over two weeks. Both workouts improved endurance capacity by almost 100%, increasing time to fatigue at 80% effort from 26 minutes to 51 minutes. In short, about 15 minutes of hard sprints spread over two weeks produced the same results as nine to 12 hours of moderate intensity effort.

Both the sprinters and the traditional riders showed a substantial increase in citrate synthase, a mitochondrial enzyme that indicates the power to use oxygen, along with increased glycogen (muscle sugar) content. Neither group, however, showed a change in maximum oxygen uptake (VO2 Max, or the ability to utilize oxygen per kg of body weight in liters per minute; it can be approximated to % max heart rate with the formula %MHR = 0.64 × %VO2max + 37) or anaerobic work capacity (ability to produce lactate, a byproduct of anaerobic metabolism).

The interesting thing about this study, is that the high intensity exercise group should have produced more anaerobic work (ie more lactate) and probably did BUT were able to clear it faster because of the short duration of the exercise. Remember that the 1st few seconds of the 30 second sprint would have been using creatine phosphate stores, before tapping into the glycogen stores.

The lower intensity exercise at 65% VO2 Max works predominantly the aerobic system (incidently, 65% of VO2 Max is probably a “moderate exercise” and is probably less demanding); thus these folks would be better able to recycle lactic acid, should the levels rise to levels requiring it. Changes in VO2Max would be able to be changed much less (3-5%) in trained individuals than untrained (up to 20%), so the findings are not that surprising.

The bottom line is that high intensity training offers some gains that are similar to traditional aerobic training with less time, and should probably be included in your training regimen.

Shawn and Ivo……..Striving to increase your knowledge base more efficiently

Does stretching make a difference? Does it enhance or inhibit performance?

Today’s discussion is not fiction or merely our opinion, you should know by now that The Gait Guys are not about presenting misinformation, we are about presenting the facts. Today’s dialogue is based on hard, solid, peer-reviewed research and neurophysiology principles. If you feel you disagree with us, please present your research papers so we can begin a productive dialogue amongst us.

Join Dr Ivo in this weeks neuromechanics to explore these questions and more. Also check out past episodes of neuromechanics weekly on our Youtube channel: “The Gait Guys”

Have a great day!

A few minutes in our Brains.

We were over at a book store on the weekend and picked up a book called Incognito written by neuroscientist David Eagleman.

The gist of the book was that the majority of brain activity is largely subconscious. That the brain is continuously processing information and working algorithms to questions and problems that we have inquired about either consciously or subconsciously. A conscious example might be pondering which new computer to buy, factoring in price, model, manufacturer, specs, hard drive size, peripherals desired, etc. Over a period of minutes, hours or days you bounce around the issues until you rationalize a best decision for your needs and wallet. On the other end, a subconscious example might be learning a new motor skill in your gait pattern. For example perhaps, a pathologic pattern is the one being learned. In one case the brain may be subconsciously learning to reduce gluteus medius muscle in an attempt reduce hip joint compression forces and thus hip pain due to a degenerative joint cartilage surface (see Dr. Allen’s recent video, Applied Hip Gait Biomechanics, Sept 15). In this scenario the brain was working out the algorithm to solve for the pain. The brain is continuously subconsciously processing to solve these problems, it is always working in the background, in sleep or in a wakeful state. We have all had these epiphany moments where the solution to a problem comes to you seemingly out of the blue. However, it is not the case. The brain had been at it for some time.

Eagleman describes the conscious brain as a CEO who is handed a final product that has been worked on by hundreds of employees for weeks, those employees being the subconscious brain parts. The CEO is the last to know, they only get to see the end success of hundreds of hours of work by the employees, and they often take full credit because they are the CEO afterall. It is a long process to achieve solutions to complicated problems. Afterall, do you really think Steve Jobs made the iPad all by himself ? Some might.

Where are we going with this ?

Unconscious incompetence: you do not know the right foot has turned out during gait.

Conscious Incompetence : someone has brought it to your attention.

Conscious Competence: you find a reasonable motor pattern to turn the foot in, but you must stay conscious of this pattern for the correction to be maintained.

Unconscious Competence: eventually unknowingly achieving the foot alignment correction. Give the brain the correct information … then give it time and the correct supportive exercise and let the brain figure it out. It will bring that foot inline eventually as long as there are not other impeding factors. The key is making sure that the pattern you teach your client , or that you institute yourself, is not a compensation. That’s the hard part ! You have to know what is right before you know what is wrong. Pick the wrong pattern and you find yourself down a fork in the road that is full of potholes and problems. Don’t guess. See someone who KNOWS. We had a guy fly in to see us yesterday and this was exactly the case. Therapy has been prescribed in-part off of a video gait analysis and incorrect physical evaluation. You can’t guess at this stuff. You gotta study!

Coming directly from our temporal lobes, we are…The Gait Guys