Neuro-adaptation, motor skills and strength. Does it come

We have discussed on recent podcasts about the concept of neuro-adaptation.
Neuro-adaptation is the initial strength gains we see in the first few weeks of corrective exercise homework, often it is more so better "coordination" of the motor patterns taught, and less so brute strength. But, it applies to strength training as well.

This strength increase is usually attributed to changes in the neural drive to muscle as a result of adaptations at the cortical or spinal level. This study investigated the change in the discharge characteristics of large populations of longitudinally tracked motor units in tibialis anterior before and after 4 weeks of strength training the ankle‐dorsiflexor muscles with isometric contractions. “

"We show for the first time that the discharge characteristics of motor units in the tibialis anterior muscle tracked across the intervention are changed by 4 weeks of strength training with isometric voluntary contractions.”
”The specific adaptations included significant increases in motor unit discharge rate, decreases in the recruitment‐threshold force of motor units and a similar input–output gain of the motor neurons.
The findings suggest that the adaptations in motor unit function may be attributable to changes in synaptic input to the motor neuron pool or to adaptations in intrinsic motor neuron properties." -Alessandro Del Vecchio et al

“These results demonstrate for the first time that the increase in muscle force after 4 weeks of strength training is the result of an increase in motor neuron output from the spinal cord to the muscle. “

The increase in muscle force after 4 weeks of strength training is mediated by adaptations in motor unit recruitment and rate coding
Alessandro Del Vecchio et al
Journal of physiology 06 February 2019

https://doi.org/10.1113/JP277250

Loss of terminal knee extension: How quickly can you process the facts ?

Some quick thoughts that must go through your mind on your examination. These thoughts must be ingrained, so that you can quickly juggle the other issues you client is coming in with that may very likely be related to the loss of left knee terminal extension.

more knee flexion may likely mean more ankle dorsiflexion , and that means more more anterior shin compartment strength is necessary to stop a quick progression to the forefoot (consider their clinical symptoms), this may mean pronation occurs more quickly (consider their clinical symptoms), it may mean more abrupt quadriceps loading since the loading does not start in more reasonable knee extension which means the quad is short now and that means increased patellofemoral compression possibilities (consider their clinical symptoms), this may mean more hip flexion on initiation of stance phase (consider their clinical symptoms), this may lead to more anterior pelvis tilt posturing and thus increased lordosis (consider their clinical symptoms), this flexed knee means that the leg is shorter which will through off pelvis symmetry (consider their clinical symptoms), this may mean more work for the contralateral hip abductors (consider their clinical symptoms), this may mean more frontal plane pelvis drift to the short leg side (consider their clinical symptoms), it will also mean 2 different step lengths which means 2 different hip extension patterns which means 2 different heel rises, and it will likely mean altered arm swing on both sides which can create changes into thoracic rotation (and of course the cervical spine sits on top of that) etc etc etc, so consider their clinical symptoms . . .

just wanted to quickly rattle off how fast your brain must juggle things, otherwise your exam is going to be knee-centered and tunnel visioned. Keep in mind, your client may not even have knee complaints, perhaps one or more of the above. But this is a perfect example of why you must examine the WHOLE client.

Perhaps this gives you even deeper understanding (combined with yesterdays "parallax binocular vision 2D post" as to why we will not give online corrective homework or consultations. There is just no way all of these things can be considered over video, Skype, Zoom or anything of the sort. Gait analysis must be done in person and encompass a hands on exam, if you do not want to miss something possible critically important, in our opinion, for what that is worth.

Shawn Allen, the other gait guy

#kneeextension, #gait, #gaitanalysis, #gaitproblems, #gaitanalysis, #gaitcompensations, #correctiveexercises, #thegaitguys

Crawling patterns and the Bird Dog look alike, but they are clearly not. Do you understand this ?

Crawling and Bird Dog, a subtle but important difference.

Can you see it ?
When we crawl, as in the photo, we use the following pattern:
- the right shoulder is in extension (but it is fixed on the ground, it is the body that is moving forward/extending over this fixated point, it is approximating the flexing right hip as the knee moves up towards the hand)
- the left hip is in extension, pairing appropriately with the right shoulder extension.
- similarly, the left shoulder is in flexion (it is over head in this photo, just like in the other photo of the runner similarly doing the same patterning but standing up, meanwhile the right hip is in flexion.
* take the photo of the runner in the green shirt, and put him in a quadruped crawling pattern as you will see that it is the same pattern as the one of me in the crawling posture.
* This is not bird dog, as seen in the photo, do not confuse them.

The Bird Dog exercise is not neurologically correct for the reason of training the proper crossed patterning from a neuro perspective. Note that in the 2nd photo, the bird dog, the same left arm is in flexion, but his left leg is in EXTENSION ! If you want to use the bird dog to teach core engagement, that is one thing, but do not think you are coordinating normal gait patterns or the proper crossed response. This is why we do not use the Bird Dog with our patients, it goes against training fundamental gait patterns.

This first photo of me in the black shirt is normal, natural, neurologically correct, cross crawling. Don't believe us ? Get on the floor and crawl like an infant, it is no where near the bird dog exercise, in crawling the coupled crossed extension and flexion responses are NOT conflicting. So, just because the Bird Dog "sort of looks like crawling" do not get it confused with crawling, because it is not. It is a mere balance exercise, some use it for the core stability, but it is one based on UN-fundamental neurologic patterning we use every day.......something called gait, and running, things we do in our sports. So understand what message you are sending to the CNS.
We are not saying the Bird Dog does not have value, not at all, but if you are not thinking about what it actually is doing, you might be driving patterns you do not want.

The Bird Dog rehab exercise is neurologically incorrect. Know what you are asking your client to do, and why..

Runners, athletes . . . Even in your drills, do it correctly !
Is this Bird Dog standing up? No, look more closely.

Photo #1: pull that right swing leg outwards with your abductors/external rotators. Do not let the knee drift inwards, it will lead to that foot targeting the midline. Plus, because of the neurologic links, it will encourage the left arm to cross the mid line (see yesterdays FB blog post). The upper limb movement can shape lower limb movement. An aggressively narrow cross over gait is undesirable in many aspects, it might be more economical, but it has a wallet full of potential liabilities.
IF you train your machine in a lazy manner, it is not unlikely it will perform as such. Get that knee under the shoulder, not under your head.

Aside from that, this is a good drill. It is neurologically correct. Note that:
- the right arm is in extension and the left hip is in extension
- the left arm is in flexion and the left knee is in flexion.
This is neurologically correct cross crawling.

* VERY important point:
the Bird Dog exercise is not neurologically correct for the reason of training the proper crossed patterning from a neuro perspective. Note that in the 2nd photo, the bird dog, the same left arm is in flexion, but his left leg is in EXTENSION ! If you want to use the bird dog to teach core engagement, that is one thing, but do not think you are coordinating normal gait patterns or the proper crossed response. This is why we do not use the Bird Dog with our patients, it goes against training fundamental gait patterns.
When we crawl, we use the following pattern:
- the right arm is in extension and the left hip is in extension
- the left arm is in flexion and the left knee is in flexion.

This is neurologically correct cross crawling. Don't believe us ? Get on the floor and crawl like an infant, it is no where near the bird dog exercise, in crawling the coupled crossed extension and flexion responses are NOT conflicting. So, just because the Bird Dog "sort of looks like crawling" do not get it confused with crawling, because it is not. It is a mere balance exercise, some use it for the core stability, but it is one based on UN-fundamental neurologic patterning we use every day.......something called gait, and running, things we do in our sports. So understand what message you are sending to the CNS.
We are not saying the Bird Dog does not have value, not at all, but if you are not thinking about what it actually is doing, you might be driving patterns you do not want.

What do the hip flexors have to do with the knee extensors ?

"It is not about your test, it is what your client displays in your test that matters. They will try to find a way. The load has to go somewhere, and they will find a place to put it, they always do. Finding out how your client cheats, compensates, recruits and fails is the value of the assessment."

This is just a small example of how I approach a client through small assessment window.
As best as I am able, knowing the absolute limitations of a supine examinations translation to vertical loading, I will approach a client's ability to stabilize in all 3 planes of movement. Today, i will micro-dissect a thought process.

The straight leg resistance test (SLR):
just a few incomplete thoughts on a SAGITTAL perspective (so as to avoid writing a book).
I will do it looking at **pelvis posture (anterior, posterior, oblique), lumbar spine posture (incr/decr lordosis), if they can keep their knee locked in a position, does the pelvis rotate, do they want to deviate into internal or external rotation at the hip, do they plantar or dorsiflex their ankle or toes. Lots to see here in how a client will recruit, and this is just a small snapshot of things they might do. Yes, head position, arm position were left out , again, to avoid a longer post today.
I will add consistent (as best as possible) resistance in the SLR test , with full locked knee, at hip 30, 45 and then full straight leg SLR (at the client's hamstring tension limit), then again at 45 degree knee lock with partial hip flexion, 90 degree hip and knee. I am changing loading vectors frequently to see if their is a directional loading failure. I am looking for their ability to provide ample resistance, and how they might cheat (see above).
But here is how my mind works through the test on the most basic level, which will give me insight on the above cheats** the client may employ.
* In the MOST SIMPLEST thought of the assessment, can they EFFECTIVELY stabilize the pelvis to the lumbar spine, can they stabilize the femur into the pelvis, can they stabilize the tibia onto the femur? It is how they choose to engage the system that matters, and that might be partly why their "Screen" shows up shoddy and may be a window into their pain.
The question is, if they fail, where are they failing and what tissues are overburdened or over protecting ? Where is the load, and where NOT is the load, going ?

"It is not about your test, it is what your client displays in your test that matters. They will try to find a way. The load has to go somewhere, and they will find a place to put it, they always do. Finding out how your client cheats, compensates, recruits and fails is the value of the assessment. This is how you need to be thinking when you perform many of the mostly useless orthopedic tests in the textbooks.

This is key,
a SLR screen will not show you any of this, it will just show you their range of motion, nothing more, not how they did it, what parts worked harder than other parts, and which parts are weak, injured or inhibited, for example. It is not what a client does, it is how they go about it that has the most value to you in helping them.

Today's article below is what spurred my rant today. It gives light that most already know, that everything is connected. And perhaps we can translate it into deeper thoughts for our clients, namely, what part is not doing its job, and where are they not connecting the parts, and where are they putting the loads ?

From the Ema study:
"Our findings indicate that hip flexion training results in substantial neuromuscular adaptations during knee extensions similar to those induced by knee extension training."-Ema et al.

We need a stable and strong core-spine-pelvis connection to display powerful knee extension, and, we need a stable and strong femur-pelvis connection as well. So, where is your client doing more or less of the work, and is it related to their hip, low back or knee pain? Or are they tossing it into the ankle perhaps? This is the beauty of the game we all play every day, if we are actually paying attention.

Now, remember my discussion last week about "adding strength to dysfunction" ? Where is your client going to put the load?, the answer, where they can/able. And that doesn't exactly mean where they should be putting it. Mindless prescription of corrective exercises is a real problem in my opinion.

Shawn Allen, the other gait guy.

#gait, #gaitproblems, #gaitanalysis, #correctiveexercises, #running, #hipflexors, #kneeextension, #SLR, #corestrength, #thegaitguys

Scand J Med Sci Sports. 2018 Mar;28(3):947-960. doi: 10.1111/sms.13008. Epub 2017 Nov 22.
Neuromuscular adaptations induced by adjacent joint training.
Ema R1,2, Saito I3, Akagi R1,3.

"Four puckered anuses and a heel strike."

So you say you do "gait analysis" and "movement screens" huh ?
If you glaze past this post, well, that would be sad to us, we put a lot of time into sharing what we feel are important (and not necessarily right) thought experiments and thoughts.

In our opinion, and this upsets some folks, screens do not tell you much of anything beyond how someone is moving. They do not tell you why they are moving that way. They do not tell you what is wrong, or right, about a person's body or why they move, or why they screen the way they do. We could even put up a darn good debate of why they could be a waste of time, when uncoupled with a clinical examination.

Much like the excessive wear on this left heel (see photo) it merely tells you that the person is, FOR SOME REASON, impacting/scuffing that heel too much. It too does not tell you why they are moving that way. (The shoe case explained in a moment).

Giving someone a "corrective homework exercise or stretch" or new movement because you "think" they are failing a screening procedure is nothing more than confirmation bias on your existing knowledge base (which for ALL of us is limited, yet hopefully expanding). Your confirmation bias might be, "I know what this screen should look like, I know what my gurus have told me it should tell me, and this client just failed the screen, so here is what you need to do to make the screen look and test better and here is what will make the client "better" (whatever that is)."

It just cannot, and is not, that simple.

Similarly, it would be like telling this person not to heel strike so hard, "Stop heel striking, stop scuffing your heel !". It is just not that simple and it is foolish to think so. We need to get to the bottom of the problem, the root cause. This means we need to hands-on examine our client, and correlate said findings to the screens. Collectively, we are just gathering information to put together a cause effect for any of our patient's problems. But you cannot just make assumptions that stroke your confirmation bias. There is logical process in place, for a good reason.

Now, why is this guy scuffing his left heel? He has no left heel pain, no left leg pain, clean foot, ankle and hip mechanics on that left side (from detailed coupled screens correlated with a detailed hands on exam including neuromuscular strength, length, skill, length-tension relationships, endurance assessments etc).

And if you think we are not guilty or above all of these mistakes we are calling out, you are mistaken. WE are on the same bus as everyone else. WE are human, we have biases, so we have to check them everyday. Just the other day I told a patient he wasn't getting better because i made and assumption based off of what i saw in his gait, and i assumed he wasn't going to fail my hop test, that it was a different problem, so i looked elsewhere, found something that confirmed my bias, and they came back 2 weeks later saying "i did my homework, i am no better." I took them into the hallway, had them go through my hop screen, and damn if i wasn't ashamed of myself, i followed with some hands on exam, and dang if I wasn't a confirmed moron. So, we screw up too, more than we like to. Some people will say "that is why we call it a medical practice". That is a soft let down. Sure, it happens, but laziness and confirmation bias happens way more often in all of us we believe.

Look at the cartoon below, the parents think the kid loves the animal mobile. From their perspective, from their limited experience lying under an animal mobile, how could they know the kid was smiling because he/she was looking up at 4 anuses? Four puckered anuses (yes, the plural is not ani. We had to look it up, too !). Go ahead, laugh, we did.
*And so, if you do make corrective exercise recommendations off of a screen, without clinical hands-on exam correlation, may your kids paint animal anuses on your bedroom ceiling to remind you of their tortured infant years.
Perspective, like this infant here staring at buttholes of stuffed animals, is amazing. It is all too often how you approach things, and with the limited (or expansive) knowledge and experience you approach it with, as to what confirmation biases you lay on things, and how you go about solving things.

*Oh, as promised, this dude in the shoes, has markedly weak RIGHT hip abductors and RIGHT lateral core (from our hands on exam and then specific loaded screens to assess and help confirm these things). This means, right lateral pelvis drift. This confirmed the visual drop of the left hemipelvis during swing phase, which allowed the left foot to have challenged clearance (he could hear the heel scuff when walking). Yes, slight left cross over gait too. The corrective exercise is to improve the right hip and lateral core stability, and establish gait awareness homework to learn how to reengage those areas. The corrective exercises were not to force more LEFT hip flexion and knee flexion to gain more clearance and stop the heel scuff. A monkey could figure that out. But that would seem logical if no examination had been done.

PS: There is no need to check his pelvic floor (see infant mobile cartoon above to extrapolate that joke). But, if you made assumptions of what homework to give him based only off of a bunch of screens, heck, you might as well check his sphincter. What do you have to lose?

WE would LOVE, love love love to give credit to whoever drew this cartoon. There is no name on it, we NEED to give them credit. It is more than brilliant. IT is an entire lecture on perspective. Send us this genius person's contact if you know who it was ! Please !!!!!!

Shawn Allen, the other gait guy

#gait, #gaitproblems, #gaitanalysis, #movementscreens, #correctiveexercises, #thegaitguys, #heelstrike

You cannot make gait corrections based on "visual assessment and oral instructions"

our Christmas #facepalm of the day

These clients changed their gait habits with visual and verbal cues. We can only hope that for the rest of their lives they have this software and someone walking beside them to give them the visual and verbal cues for the rest of their lives so that they can continue to walk "normally" again, which is likely a compensation to their compensatory deficits (instead of earning the changes through championing their way through their deficits.)

Uggg. We have said this over and over again, and will say it again here.
You cannot make gait corrections based on "visual assessment and oral instructions" (as this paper mentions). This is borderline foolish. A person's gait has changed for a reason, they did not do it consciously. Thus, they should not lean towards a simple conscious correction. Their body made the adaptive changes one can see on gait evaluation because of an adaptive deficit, weakness, pain, compensatory motor strategy etc. There is a reason their gait has changed. Thus, the fix must come from addressing these causes, not merely from a visual cue or a verbal instruction. This is foolish. This is what is wrong with the gait assessment world. This is why you cannot and should not give corrective exercises from a gait analysis, not until you examine your client clinically for deficits, weakness, faulty motor patterns, sensory deficits, etc. This is just not prudent work without the clinical evaluation, hands on stuff, smart stuff.
These clients changed their gait habits with visual and verbal cues. We can only hope that for the rest of their lives they have this software and someone near by to give them the visual and verbal cues for the rest of their lives so that they can walk normally again (instead of earning the changes through championing their way through their deficits.)
#facepalm of the day

http://www.jbiomech.com/article/S0021-9290(17)30570-5/abstract

A gait retraining system using augmented-reality to modify footprint parameters: Effects on lower-limb sagittal-plane kinematics . Sami Bennour, Baptiste Ulrich, Thomas Legrand, Brigitte M. Jolles, Julien Favre

You won't read this. So send it to a colleague who will.

Beating a point to near-death. Consider this our Thursday Rant.

Yes, we won't let this go, and, you should not either.

We highlight the word ADAPTIVE below, because it is the key to all of this.

"The observed postural responses could be viewed as an ADAPTIVE process to cope with an unilateral alteration in the hip neuromuscular function induced by the fatiguing exercise for controlling bipedal stance. The increase in CoP displacements observed under the non-fatigued leg in the fatigue condition could reflect enhanced exploratory "testing of the ground" movements with sensors of the non-fatigued leg's feet, providing supplementary somatosensory inputs to the central nervous system to preserve/facilitate postural control in condition of altered neuromuscular function of the dominant leg's hip abductors induced by the fatiguing exercise."-*Vuillerme N1, Sporbert C, Pinsault N.

When one prescribes or chooses a corrective exercise for a client, one based sheerly on what is visualized as an "apparently" faulty movement pattern or aberrant screen, one is making many assumptions. Assumptions that are likely not entirely correct (we are being kind, most assumptions made based on partial fragmented information are incorrect to a high degree).

Here is comes again, . . . . what you SEE and TEST in your client's movement is not what is wrong with them most of the time. What you see is how your client is ADAPTING to the variables they can engage, avoiding the ones that are painful or perceived as unstable, or finding ways around immobility and as the article as quote above suggests. This was a basic tenet of Karel Lewit's and Janda's work to not focusing on the area of pain, rather to seek out the root cause, we are just saying it in a different manner.

Continuing, we also adapt around fatigue which can take place even in everyday tasks and how we move around our world, yes, even in our gait. Yes, you are seeing a client's best attempts, ones that are likely deeply rooted and now their new norm, their baseline to base all other patterns off of. Their attempts can be based off of immobility, instability (true or functional), lack of skill, proprioceptive deficits, fatigue (lack of baseline endurance), lack of strength or power. For some clients, forget challenging screens that really test them, heck, we find some athletes do not even have the requisite baseline endurance or strength in a few primary fundamental patterns of which they have built more robust patterns atop of. We all to often read about "robustness" of a skill and pattern and interpret it as a good thing. Robustness can also be build atop of a bad pattern of movement, atop of poor stability patterns.

Thus, asking a client to change that ADAPTIVE norm, based off of what you visualize, based on the working parts available to them, without rooting out the cause, is asking them to compensate around their new norm base of compensation. When done this way, we are merely giving our client armor to their dysfunction, faulty robustness if you will. We are in fact moving further from the remedy. To correctly play this multi-layered game of helping people, one has to examine the client, not just put them through screens and assessments that show us (and them) what they can and cannot do.

There is an awful lot of armchair doctoring going on out there, thankfully it all comes from a good place in the heart's of many good folk. We have so many people come in to see us who have problems and a list of corrective exercises that have been prescribed to them, exercises that clearly have been based off of correcting what is seen in their screens and movements. We discuss their workout patterns, their activities, and hear about how they are attempting to build up their bodies for the apparent good. But all to often, with a client in front of us in pain, we hear the clues that the problem is being exercised around. Meaning, building robustness on top of a dysfunctional base somewhere in their system. Many of these people have been given these exercises as part of their corrective work and strengthening programs at their place (gym, box, trainer, coach etc). Many times there was no in depth hands on examination coupled with screens and gait to root out the cause of why they are moving the aberrant way that they are. We all must commit ourselves to a complete process for our clients. Screens and tests and exercises are not enough. Please read yesterdays post if you have not already, we make our point once again in a video case.

To close this post, we fully acknowledge regularly that we are on the same bus to the same temple of higher wisdom as everyone else that reads these kinds of posts. We write to share, but we write to learn, to dive deeper into our thoughts, to challenge our biases and rooted assumptions through thought experiments, challenging thoughts and old ways that get us into troubled automated patterns of approaching all things. Again, we write to learn. And, part of that learning is accepting our limitations and hearing from others who are wiser in other areas than us, so, please comment and add insight below if you wish. Debates are good, for us all.  Pull up a chair, grab a pint, join us around the hearth for some gab.

Shawn Allen, . . .  the other gait guy.    www.doctorallen.co    &    www.shawnallen.net

"One of the few ways I can almost be certain I'll understand something is by sitting down and writing about it. Because by forcing yourself to write about it and putting it down in words, you can't avoid having to come to grips with it. You might be wrong, but you have to think about it very intensely to write about it. So I use writing as a learning tool. " - Hunter S. Thompson

*Postural adaptation to unilateral hip muscle fatigue during human bipedal standing.

Gait Posture. 2009 Jul;30(1):122-5. doi: 10.1016/j.gaitpost.2009.03.004. Epub 2009 Apr 28.

Vuillerme N1, Sporbert C, Pinsault N.

Is this a gluteus medius foot targeting problem in swing phase or is this a loss of internal hip rotation? Or . . . .

Is this a gluteus medius foot targeting problem in swing phase or is this a loss of internal hip rotation? Or . . . .

You have to examine your client to know what to treat, a gait analysis or a series of screens is not enough. The saying "an exercise is a test and a test is an exercise" has some sharp edges around it. A screen doesn't tell you what exercise a client necessarily needs or should be prescribed.
This stuff really does matter.
What you see is not the problem , it is their compensatory strategy in coping with a problem. When someone has a pebble in their shoe and they walk on the outside edge of their shoe to avoid the pebble the solution is not to tell them to stop walking on the outside of the shoe, the solution is the de-pebble the shoe. Corrective exercises can be a similar path to this pebble analogy. One must look deeper and beyond what we see in our clients, we merely see how they have adapted, not the problem. A Trendelenburg leaning gait is not met with a solution to prescribe a corrective exercise to correct the lean, the solution is to see why the client is reducing the compressive loading across the hip. Stop giving corrective exercises if you are not examining your client. Yes, that means you need to have hands on diagnostic skills. Sorry.

Loading the wrong pattern drives a compensation, and maybe another problem or a compensation to the compensation deeper.

Loading the pattern that is corrective, the one that solves the deficit leading to the gait you see should be your target. Corrective exercises are supposed to be corrective to the problem, not to the gait aberation you see. Without the exam to solidify proper path, corrective exercises often are directed at the things we see, not the aberation that drove what we see. Be part of your clients solution.
If you aren't examining your client, you don't know for certain what you are actually doing.

This is me, Dr. Allen, i am walking in a matter to prove my point.
Do i have a loss of right internal hip rotation (thus the externally rotated limb?). Do i have a swing leg gluteus medius weakness that is allowing me to adduct the limb rendering a mere foot targeting problem? Do i have weak peronei ? A weak glute max ? A right frontal plane drift that i am avoiding by turning my leg out so i can use my quads to help the deficient glutes better block the frontal plane drift ? I could go on an on as to possible causes.
Or do i merely have a pebble in my shoe?
Mic drop.

To give a corrective exercise you have to know what is wrong. That means you have to have the knowledge and the hands on skills to diagnose the "why". So you can prescribe the correct "how".

Shawn Allen, one of the gait guys

A few minutes with Shawn, Episode 1

Pruning, Baking, & Corrective Exercise.

Just a few thoughts, rants, pearls, analogies and stories, once or twice a month . . . mostly leading towards a clinical point of view and things I find myself thinking about.

Where to download:

http://traffic.libsyn.com/thegaitguys/Minutes_with_Shawn_1.mp3

http://thegaitguys.libsyn.com/a-few-minutes-with-shawn-1

http://directory.libsyn.com/episode/index/id/5910367

More foot exercise studies to confuse you.

Don't necessarily believe all that you read. Please to not take away from this study that these 4 exercises: short-foot exercise, toes spread out, first-toe extension, second- to fifth-toes extension are golden goose exercises to rehab your athlete. On first glance if one is not thinking, that could be a mistake in translation.

"The intrinsic foot muscles maintain the medial longitudinal arch and aid in force distribution and postural control during gait."  That is a pretty bold statement by the study's authors. We would argue that a far less misleading statement would be that "the intrinsic foot muscles are a piece of the puzzle, just a piece, and to dismiss the powerhouse tibialis anterior, tibialis posterior, long and short toe flexors and particularly the extensors is a glaring oversight".  Yes, I know, the authors just wanted to study the intrinsics, I get it, -- one just has to be careful of the conclusions made when the study is so microscopic compared to the global perspective at hand.  Please, read on.

This study tried to correlate the effects of these 4 exercises: short-foot exercise, toes spread out, first-toe extension, second- to fifth-toes extension on activation of the foot intrinsics muscles they chose to observe (abductor hallucis, flexor digitorum brevis, abductor digiti minimi, quadratus plantae, flexor digiti minimi, adductor hallucis oblique, flexor hallucis brevis, the interossei, and lumbricals).

They looked at the activation before and after exercise in just 8 athletes. They did not look at non-athletes and yes, this is a terribly small N sampling and the study only used T2 weighted MRI to make these conclusions.

The study's conclusion was "Each of the 4 exercises was associated with increased activation in all of the plantar intrinsic foot muscles evaluated.".  

Here is my concern*. 
Did they consider the various foot typings ? (*Caveat, I have not read the entire study, I am trying to get it). There are many variables to consider including arch integrity, forefoot type, rearfoot type, foot flexibility, step width, step length, client weight amongst other things. Yes, that makes for a near impossible study, I get it. And, it does not appear they had a control study that looked at what happened right after walking. Wouldn't it be fair, and wise,  to see what the study showed after barefoot walking for 1-2 minutes ? I bet many of these muscles show significant activation there as well, after all, they were weight bearing and stepping down on the foot which requires the muscles to be activated and utilized.  So, does that then mean these 4 exercises are any better than walking ? Does that mean they will suffice for homework for your client ? Does that mean they will strengthen these muscles ? And, does activation mean proper pattern utilization of these muscles, meaning, is there functional translation over to functional use ? Yes, that is not what the study was looking at, but for darn sure that would have been nice info to know. Just take the study for what it found, and do not step beyond those tiny boundaries. We hope that is what they will go for in the next stage of study.  To be fair, they also concluded, "These results MAY have clinical implications for the prescription of specific exercises to target individual intrinsic foot muscles."  Safe words. Yes, I capitalized the word MAY.

- Dr. Shawn Allen, one of the gait guys.

Thomas M. Gooding, Mark A. Feger, Joseph M. Hart, and Jay Hertel (2016) Intrinsic Foot Muscle Activation During Specific Exercises: A T2 Time Magnetic Resonance Imaging Study. Journal of Athletic Training In-Press. 
http://natajournals.com/doi/abs/10.4085/1062-6050-51.10.07
http://dx.doi.org/10.4085/1062-6050-51.10.07

Screens are valuable. But, only if they screen all the pertinent areas, only if the screener knows what to look for, and only if one realizes they are just a screen and not a platform for corrective exercise prescription. Guys like us and Gray Cook have been saying this for years.

“Is your client feeling better because they are truly fixed, or have your prescribed corrective exercises merely raised the capacity and durability of their compensation ?  Welcome to a global industry problem.”  -Dr. Allen

Which hip will have troubles extending ?

Remember this quiz question from 2 weeks ago ? I talked about how the body will compensate to level the pelvis (and eyes and vestibular apparatus).

Lets go further down the rabbit hole.  Here is your question of the week (you may have to go back and review the prior blog post if you are unsure of how the body will cope with the slope.  Here is that first blog post.

Question: Which hip will have troubles getting into hip extension and thus terminal glute-hip-pelvis stabilization ?

Answer:  scroll down (at least think about it for a second)

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Answer:

The leg on the up slope of the beach, the non-water side leg will have to be in a modest degree of knee flexion to shorten and accommodate to the slope. A Flexed knee is not an extended one and it will be far more difficult to extend the hip and get into the glutes. Propulsion will also be compromised.  For you indoor small track runners this will happen to you on the inside leg on the curves of the track. This is why we see so many hamstring injuries during indoor track.  Think about it ! It is not just bad luck.  Go ahead, tally up  your teams history of hamstring injuries, you should find more on the left leg for track runners. It is simple applied biomechanics.   Also, imagine the altered demand on the quadriceps on that flexed knee (the right knee in the picture above, and the left knee in circle track runners). Furthermore, what is the likelihood that the right pelvis will deviate into an anterior tilted posture ? You bet ya, a greater tendency, and thus a possibly shortened quadriceps/hip flexor mechanism.  Do you think this could inhibit hip extension and gluteal function ? You bet ya.  Oh, and one more thing, if you are true gait nerd, you should have asked yourself one more question, what about ankle rocker ?  Yes, you will need more ankle rocker on the beach side foot (flexed knee side). When the knee flexes, there must be more ankle rocker for this to occur, if not, you may implode into some unwelcome arch collapse, because arch collapse offers more false ankle rocker. What a mess huh !   Now, do not be shocked EVER again when your client’s come back from a sunny beach vacation from walking the beaches for hours every day, and find themselves a stark raving mad mess.  It is not the salty ocean air or the tequila, it is the slope. One could make a case that walking up and down the beach should balance things out, but that is only if we are balanced and symmetrical when we start out. Gravity always wins.

One final rant. If you are offering “corrective exercises” to your clients, you had better know at least the basics of movement and biomechanics. And further more, you had better know how to examine for them, and that means hands on assessment of the body, not just looking at how your client moves through a battery of tests. If the prior blog post (here) and today’s blog post principles are not remedial principles of knowledge for you, offering corrective exercises without this knowledge and a physical exam to confirm your assumptions is fraught with disaster, or at least helping your client to build deeper compensations on their prior compensations. Is your client feeling better because they are truly fixed, or have your prescribed corrective exercises merely raised the capacity and durability of their compensation ?  This is the kind of stuff that keeps my new patient scheduling booked at 4-8 weeks out … . .  frustrated clients.

This is why we do not offer online consultations like some do. Because, we have not figured out how to obtain the third dimension needed in our gait and movement observation (thank you Oculus Rift, the future is near) but more so, we cannot take that information and put it together with our own physical examination to determine whether if what we are seeing is the actual problem, or a compensation. Here in lies the pot of gold.

Another clinical pearl from Dr. Allen