What do we mean when we talk of facilitated & inhibited muscles?
October 4, 2009 – 5:57 pmOften in workshops and just yesterday on Facebook, I encounter therapists inquiring about the meaning of muscle facilitation and inhibition. Why is this central nervous system process so important to bodyworkers. I’d like to hear what your take is and how you use it in a therapeutic setting.
5 Responses to “What do we mean when we talk of facilitated & inhibited muscles?”
I don’t know about you but this Facilitated and Inhibited concepts where not covered in massage school and I got great difficulty at finding a good description of what they are and how they are created. I’ve spent many hours searching the web and books through google books and found partial and sometimes contradictory answers, especially between the physios and the osteopaths books. I would like to get an answer from someone who clearly understand how it works. Yes, that would be you Erik
Questions
1. Muscle facilitation and inhibition, what does it really mean? How does that phenomenon occur?
2. What are the symptoms? Is it muscle tightness? Is it jerky motor control? Is it loss of strength?
3. How can the bodyworker find out if a muscle is facilitated or inhibited? Is there a special test?
4. What can we do about it?
Even though I don’t clearly understand the concepts yet, I’ve developed my own theory which I can use practically. I’ve decided to associate a tight muscle (higher tone) with a facilitated motor nerve and a weak muscle (reduced tone) with an inhibited motor nerve. I’m pretty sure that this is not the complete picture but that’s enough to be usable. The second part of the theory would be that a series of impulses from the nervous system would reach the motor neuron. When there is enough impulses to pass the firing “threshold”, the motor neuron would fire and the muscle fiber would start to increase in tone or contract. So there would be two variables here: 1. The amount of impulses going to the motor neuron and 2. The threshold in the motor neuron that could be high or low.Since some of these impulses can be controlled by the bodyworker (decompressing a joint, relaxing the person, shortening a muscle) this allows us to control the amount of input going to the motor neuron and eventually affect the tonicity. Same with spindle work, as mentioned by Erik, this could increase the amount of impulses going to the CNS and it might just make the decision of sending more impulse back to the motor neuron of that same muscle.
Examples:
Shortening muscle -> Decrease firing of receptors (spindles, golgi, etc) -> CNS (decision) -> Decrease firing to motor nerve -> Decrease tone.
Spindle work -> Increase firing of spindles -> CNS (decision) -> Increase firing of motor nerve -> Increased tone.
That’s the way I understand facilitation / inhibition. The problem here is that I don’t understand why, in the upper crossed syndrome, the pecs get facilitated when they should stop pulling and rhomboids inhibited when they should be pulling. I would expect the CNS to make the decision of sending lots of impulses to the motor neurons of the rhomboids so they would contract like mad and bring the shoulders back. Something is wrong somewhere in that principle and I hope it’s my understanding.
I’ll put more comments after your answer.
By Serge on Oct 4, 2009
That’s a start there from Chaitow: http://books.google.com.au/books?id=utJagjr-HuIC&pg=PA70&dq=muscle+facilitation&ei=w2HJSojXHJywkASVk72uAw#v=onepage&q=facilitation&f=false
By Serge on Oct 4, 2009
Thanks for the post Serge:
Rather than further discussing the neurology of how bombardment of afferent stimuli can up-regulate neuron excitability causing facilitation, I think it’s easier to discuss the resultant muscle imbalances, i.e., upper & lower cross syndromes.
Muscular imbalances may result from abnormal afferent information due to (1) faulty posture, (2) joint blockage, (3) CNS malregulation, (4) painful stimuli, (5) excessive physical demands, (6) habitual movement patterns, and (7) psychological stressors.
Overloading the musculoskeletal system seems to facilitate the postural muscles (pecs, upper traps, etc.) causing hypertonicity and shortening…especially when the person is fatigued. Dynamic muscles (rhomboids, lower traps, etc.), become inhibited from overload causing substitution by the postural muscles during principle movement patterns which reinforces and perpetuates the imbalances.
Janda believed our sedentary society’s lack of variety of movement patterns also facilitates the postural muscle system. We’ve all seen how prolonged sitting in flexed positions allows gravity to pull the heavy head forward on the shoulder girdle and the shoulders forward on the rib cage which perpetuates the upper cross syndrome (see http://www.erikdalton.com/articles.htm )
When developing a treatment program, it’s important to know which muscles behave as postural or dynamic muscles and to investigate (via clinical reasoning) the possible causes for abnormal afferent information. This allows the therapist to treat not only the muscular imbalances but also correct the cause of the aberrant stimuli.
Some muscles tighten from fascial adhesions and some from facilitation. It’s important to include techniques that address both the neurologic as well as the fascial contracture issues. But what about fascial myofibroblasts? Are they stretch receptors? How do you treat ‘em?
By Erik Dalton on Oct 5, 2009
How would a flow chart of troubleshooting the facilitation would go?
Referring to “(1) faulty posture, (2) joint blockage, (3) CNS malregulation, (4) painful stimuli, (5) excessive physical demands, (6) habitual movement patterns, and (7) psychological stressors.”
would you:
1. Check the posture, if ok
2. Check the joint (mobilize, decompress, compress, etc), if ok
3. Check for Trigger Points (painful stimuli …)
4. then what? we don’t have any tools to test or treat CNS malregulation, improper movement patterns, psychological stressors… what do I do with my client then? I guess I would refer.
How much time do you spend treating imbalances until you reach the conclusion that it is cause by something else outside your control and refer on to someone else?
By Serge on Oct 7, 2009
Interesting article on resting tone:
http://web.mac.com/stephenlevin1/_StephenLevins_Biotensegrity/Muscles_at_Rest.html
By Serge Rivest on Nov 28, 2009