the mechanism of muscle energy techniques

Picked this up from out discussion forum.

Hope this proves useful.

We're also hoping we could share more with you on the 22nd of February, in PASIG. The posting for that sharing session (some call them workshops) appears on this site as well. for registration, Harold can be reached at 09274515589 and via this site.

Back to the that discussion -

Re: Osteopathy For All RE: MET

> David
The terms Post isometric relaxation (PIR) and reciprocal inhibition (RI) are no longer valid in the strictest sense, since these mechanisms have been shown to not be responsible for the effects of MET.
In the 3rd edition of my MET book (Elsevier 2006) Gary Fryer PhD Bsc(Osteopathy) ND has a chapter on the research evidence relative to MET which explains why PIR and RI, while valid concepts in themselves, are not involved in MET's efficacy - but that the increased tolerance to stretch that follows an isometric contraction (of agonist or antagonist) results from some other process(es).

One suggestion that has emerged from the background of research into endocannabinoids (Mcpartland et al) suggests that these endogenous hormones, which are up-regulated following MET (and a variety of other bodywork modalities including myofascial release) and which are analgesic and anti-inflammatory in their actions (along with producing a mild euphoria) may offer a partial explanation.
Other possible mechanisms involve the effect on associate muscles of either compression or light stretching on ligaments, which offers possible explanations for the efficacy of both MET and indirect methods such as strain counterstrain. (Solomonow 2009)

To answer your actual query:
In the sense that contraction involving agonist or antagonist muscles relative to a joint restriction will induce changes that allow easy mobilisation, it doesn't really matter which you use, or whether you induce a co-contraction, or indeed whether you don't use a contraction at all but employ rhythmic pulsating contractions (Ruddy's approach) - which is my preferred method since it also has the benefit of helping encourage enhanced proprioceptive function in the joint while simultaneously improving local circulatory and drainage features.
I hope this clarifies the issues you were asking about.

It simply means that the explanation for how MET works is in need of updating.

It does not change the practicality of its' application a jot
They after all built some of their original work (or Mitchell senior did at least) on Ruddy's pulsed approach ('rapid resisted duction' he called it)

Ruddy's approach (originally developed to treat the intrinsic eye muscles! but that's another story), was to engage the restriction barrier, and to then have the patient produce 20 or so minute rhythmic contractions (in the space of 10 seconds), towards the barrier, against practitioner resistance.
After which the new barrier would be engaged and so on....or the joint would be free.
In my own work I use Ruddy's directions as a starting point but do not restrict the directions of the pulsed effort to his 'towards the barrier' - injunction.. ..some very odd directions sometimes work brilliantly.
The pulsed efforts are the barest initiation of effort, no actual movement taking place.
His strong directive was 'no wobble, no bounce'

Leon

REF:
Fryer G 2000 Muscle Energy Concepts –A Need for a Change. Journal of Osteopathic Medicine. 3(2): 54 – 59
Fryer G 2006 MET: Efficacy & Research IN: Chaitow L (Ed) Muscle Energy Techniques (3rd edition) Elsevier, Edinburgh

Ruddy T 1961 Osteopathic rhythmic resistive duction therapy. Yearbook of Academy of Applied Osteopathy 1961, Indianapolis, p 58

Solomonow M 2009 Ligaments: A source of musculoskeletal disorders.J Bodywork & Movement Therapies 13(2): IN PRESS

Smith, M., Fryer, G. 2008 A comparison of two muscle energy techniques for increasing flexibility of the hamstring muscle group Journal of Bodywork and Movement Therapies 12 (4), pp. 312-317

McPartland, J.M. 2004 Travel trigger points - Molecular and osteopathic perspectives Journal of the American Osteopathic Association 104 (6), pp. 244-249

Hamilton, L., Boswell, C., Fryer, G. 2007 The effects of high-velocity, low-amplitude manipulation and muscle energy technique on suboccipital tenderness International Journal of Osteopathic Medicine 10 (2-3), pp. 42-49

McPartland, J.M. 2008 The endocannabinoid system: An osteopathic perspective Journal of the American Osteopathic Association 108 (10), pp. 586-600
Magnusson M Simonsen E Aagaard P et al 1996a Mechanical and physiological responses to stretching with and without pre-isometric contraction in human skeletal muscle Archives of Physical Medicine & Rehabilitation 77:373-377

Magnusson M Simonsen E Aagaard P et al 1996b A mechanism for altered flexibility in human skeletal muscle. Journal of Physiology 497(Part 1):293-298