On the subject of manual muscle work…There is more to it than meets the eye….

Following with our last few posts, here is an article that may seem verbose, but has interesting implications for practitioners who do manual muscle work with their clients. We would invite you to work your way through the entire article, a little at a time, to fully grasp it’s implications.

Plowing through the neurophysiology, here is a synopsis for you:

Tactile and muscle afferent (or sensory) information travels into the dorsal (or posterior) part of the spinal cord called the “dorsal horn”. This “dorsal horn” is divided into 4 layers; 2 superficial and 2 deep. The superficial layers get their info from the A delta and C fibers (cold, warm, light touch and pain) and the deeper layers get their info from the A alpha and A beta fibers (ie: joint, skin and muscle mechanoreceptors).

So what you may say.

The superficial layers are involved with pain and tissue damage modulation, both at the spinal cord level and from descending inhibition from the brain. The deeper layers are involved with apprising the central nervous system about information relating directly to movement (of the skin, joints and muscles).

Information in this deeper layer is much more specific that that entering the more superficial layers. This happens because of 3 reasons:

  1. there are more one to one connections of neurons (30% as opposed to 10%) with the information distributed to many pathways in the CNS, instead of just a dedicated few in the more superficial layers
  2. the connections in the deeper layers are largely unidirectional and 69% are inhibitory connections (ie they modulate output, rather than input)
  3. the connections in the deeper layers use both GABA and Glycine as neurotransmitters (Glycine is a more specific neurotransmitter).

Ok, this is getting long and complex, tell me something useful...

This supports that much of what we do when we do manual therapy on a patient or client is we stimulate inhibitory neurons or interneurons which can either (directly or indirectly)

  1. inhibit a muscle
  2. excite a muscle because we inhibited the inhibitory neuron or interneuron acting on it (you see, 2 negatives can be positive)

So, much of what we do is inhibit muscle function, even though the muscle may be testing stronger. Are we inhibiting the antagonist and thus strengthening the agonist? Are we removing the inhibition of the agonist by inhibiting the inhibitory action on it? Whichever it may be, keep in mind we are probably modulating inhibition, rather than creating excitation.

Semantics? Maybe…But we constantly talk about being specific for a fix, not just cover up the compensation. Is it easier to keep filling up the tire (facilitating) or patching the hole (inhibiting). It’s your call

The Gait Guys. Telling it like it is and shedding light on complex ideas, so you can be all you can be.

link: http://jn.physiology.org/content/99/3/1051

On the subject of manual muscle work…There is more to it than meets the eye….

Following with our last few posts, here is an article that may seem verbose, but has interesting implications for practitioners who do manual muscle work with their clients. We would invite you to work your way through the entire article, a little at a time, to fully grasp it’s implications.

Plowing through the neurophysiology, here is a synopsis for you:

Tactile and muscle afferent (or sensory) information travels into the dorsal (or posterior) part of the spinal cord called the “dorsal horn”. This “dorsal horn” is divided into 4 layers; 2 superficial and 2 deep. The superficial layers get their info from the A delta and C fibers (cold, warm, light touch and pain) and the deeper layers get their info from the A alpha and A beta fibers (ie: joint, skin and muscle mechanoreceptors).

So what you may say.

The superficial layers are involved with pain and tissue damage modulation, both at the spinal cord level and from descending inhibition from the brain. The deeper layers are involved with apprising the central nervous system about information relating directly to movement (of the skin, joints and muscles).

Information in this deeper layer is much more specific that that entering the more superficial layers. This happens because of 3 reasons:

  1. there are more one to one connections of neurons (30% as opposed to 10%) with the information distributed to many pathways in the CNS, instead of just a dedicated few in the more superficial layers
  2. the connections in the deeper layers are largely unidirectional and 69% are inhibitory connections (ie they modulate output, rather than input)
  3. the connections in the deeper layers use both GABA and Glycine as neurotransmitters (Glycine is a more specific neurotransmitter).

Ok, this is getting long and complex, tell me something useful...

This supports that much of what we do when we do manual therapy on a patient or client is we stimulate inhibitory neurons or interneurons which can either (directly or indirectly)

  1. inhibit a muscle
  2. excite a muscle because we inhibited the inhibitory neuron or interneuron acting on it (you see, 2 negatives can be positive)

So, much of what we do is inhibit muscle function, even though the muscle may be testing stronger. Are we inhibiting the antagonist and thus strengthening the agonist? Are we removing the inhibition of the agonist by inhibiting the inhibitory action on it? Whichever it may be, keep in mind we are probably modulating inhibition, rather than creating excitation.

Semantics? Maybe…But we constantly talk about being specific for a fix, not just cover up the compensation. Is it easier to keep filling up the tire (facilitating) or patching the hole (inhibiting). It’s your call

The Gait Guys. Telling it like it is and shedding light on complex ideas, so you can be all you can be.

link: http://jn.physiology.org/content/99/3/1051

Muscle Activation Concerns

We are concerned about some things that are showing up in our clinics lately. Strange injury patterns we have not seen before. We know you are all very busy, because you are the best what you do, but we hope that by sharing these 2 articles with you we can all further raise this team of practitioners, coaches, physical therapists, trainers, pilates and yoga instructors, surgeons etc and work even more effectively as a team.  
This issue is about muscle activation or facilitation.
As you are all learning, this game is more than just turning muscles on, and there are risks to turning something on when the central nervous system has decided it is not safe to turn something on. We are all treating people who are slouched over all day either as students or at desk jobs and thus everyone (seeing as they are all dropped into hip, knee and cervical, thoracic and lumbar spine flexion) will have some degree of inhibited glutes (and thus reciprocal neuro-protective hip flexor tightness) that appear to need activated when the truth is that they need more central extension facillitation. Activating the glutes when there is a central flexion inhibition driver overrides the nervous system’s protective inhibition response. Hence the near-epidemic of hamstring and hip flexor/groin/labrum tear problems we are seeing !   There are logical reasons why something is not activated. Sometimes it is a 
1. muscle skill pattern (large diameter nerve, all muscle fiber diameters), 
2. sometimes it is an endurance problem (large diameter nerve, small muscle fiber diameter),
3.  sometimes it is a strength problem (largest diameter nerve, largest diameter muscle fibers). 
Knowing a problem is driven by 2 or 3 will tell the practitioner that activation will not solve the problem and that activation can force a compensation pattern that can lead to a future injury. Also, sometimes it has nothing to do with the muscles motor nerve activity, it may in fact be about the reciprocal inhibitory neurosensory input (see our post on reciprocal inhibition here). 
Hence we wanted to share 2 articles we wrote. These articles were spurred by the magnified influx in the last year of injuries that appear compensatory, meaning they seem to have occurred because alternative compensatory motor patterns were encouraged where there appear to be clear signs that they should not have been encouraged.  In other words, sorry to say this, people with a weaker understanding of how and why the nervous system works are using muscular activation as a tool when it is the wrong tool. When you are pounding a nail, using a screwdriver won’t get you good results, and might get you the wrong results. But, if all you have is a screwdriver … . .
The blog posts are below. We strongly believe that many of these injuries we are seeing are not necessary. We always ask ourselves when a person who we have been working on says to us “honest doc, I really did not do anything, I was just running comfortably and the hamstring grabbed at me for no apparent reason.”  These stories always make us look in wards and ask “is this injury my fault ?” “Did this occur because I was activating the wrong muscles and wrong patterns thus forcing them into a less worth protective pattern because I thought I knew better than their nervous system did ?” When we want to learn we judge ourselves and our actions  harshly, for we know we make mistakes and we know we are still students. We know that if it appears simple, it might be a good time to step back and think it through a little more. 
Don’t just be an muscle “activator”, be a thinker who occasionally activates when it is appropriate.  The nervous system knows better than you do, accept this and try to figure out why it is shutting things down.
Shawn and Ivo

image from : http://www.emeraldinsight.com/books.htm?chapterid=1775219&show=html

Podcast 49: Winter Running Biomechanical Problems

A. Link to our server:

http://thegaitguys.libsyn.com/podcast-49-winter-running-biomechanical-problems

B. iTunes link:

https://itunes.apple.com/us/podcast/the-gait-guys-podcast/id559864138

C. Gait Guys online /download store (National Shoe Fit Certification and more !) :

http://store.payloadz.com/results/results.aspx?m=80204

D. other web based Gait Guys lectures:

www.onlinece.com   type in Dr. Waerlop or Dr. Allen,  ”Biomechanics”

________________________________________

* Today’s show notes:

Neuroscience 

1. Skulpt Aim: World’s First Device to Measure Muscle Fitness with One Touch | Indiegogo

http://www.indiegogo.com/projects/skulpt-aim-world-s-first-device-to-measure-muscle-fitness-with-one-touch/

3. Something to consider when it comes to injuries, whether they are closed injuries and certainly when they are open injuries !
 
Bacteria directly activate sensory nerves
http://www.bodyinmind.org/bacteria-directly-activate-sensory-nerves/

Gait Talk:
4. walking on ice vs on slipper hardwood floors with socks.
what are the gait changes that need to be adapted
are their neurologic effects ?

5. The Pros and Cons of Stride Variability

Our Disclaimer !  
6. From a blog reader:
Hi Gait Guys – amazing wealth of info you’ve provided! I’ve been suffering from severe foot pain (peroneal tendonitis and general top/side foot pain) for about a year now which has turned me from very active to completely sedentary since I can hardly walk. My ortho gave up on me after 9 months of treatment incl. countless oral and injected steroids and 2 months in a boot. Then this morning I found your site – and the “The Gaits of Hell” video. That’s my walk!! Is it really all in my back?
7. From a blog reader
Question: when my feet point straight my knees point outward from my body. I’ve heard it called external femoral torsion …

8 . Effects of Nonslip Socks on the Gait Patterns of Older People When Walking on a Slippery Surface

9 . National Shoe Fit Program
10. Running Form: Recognizing Patterns and Posture

http://www.engagingmuscles.com/2013/12/03/running-form-recognizing-patterns-and-posture/

And what have we here?

The above is a pedograph, a simple, effective pressure map of the foot as someone is walking across an inked grid. For more info on pedographs, click here.

Did you note the increased ink present under the great toe bilaterally? What could be causing this? If you look carefully, you will note that it is at the base of the proximal phalynx of the great toe. This could be none other than the tendon of the flexor hallucis brevis!

This bad boy arises from the medial part of the under surface of the cuoid and the adjacent 3rd cunieform, with a small slip from the tendon of the tibialis posterior. As it travels forward it splits into two parts, which are inserted into the medial and lateral sides of the base of the proximal phalanyx of the great toe. There is a sesamoid bone present in each tendon, which offers the FHB a mechanical advantage when flexing the toe.  The medial portion is blends with the abductor hallucis and the lateral portion blends with the adductor hallucis.

Had the increased printing on the pedograph been more distal, it most likely would have been due to increased action of the flexor hallucis longus.   Had it been more proximal (under the head of the 1st metatarsal) it would have been due to the peroneus longus.

Cool, eh?

Reading pedographs and making you a sharper clinician/coach/trainer/sales person is just one of the many skills we try to teach here on the blog. Keep up the great work!

The Gait Guys

“And the Grinch, with his Grinch-feet ice cold in the snow, stood puzzling and puzzling, how could it be so? It came without ribbons. It came without tags. It came without packages, boxes or bags. And he puzzled and puzzled ‘till his puzzler was sore. Then the Grinch thought of something he hadn’t before. What if Christmas, he thought, doesn’t come from a store? What if Christmas, perhaps, means a little bit more?”

Wishing you a safe and blessed holiday! Keep your glutes engaged and your toes up!

The Gait Guys