Evastar
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Muscle energy techniques (MET) have been used for almost 50 years to reduce abnormal muscle tension and to improve mobility. MET is a versatile intervention that may be employed to treat clients with neuromusculoskeletal conditions. MET was initially described within the osteopathic profession by Drs. T.J. Ruddy and Fred Mitchell. During the same period, Knott and Voss were developing the Proprioceptive Neuromuscular Facilitation (PNF) Technique in physical therapy. MET was later refined by several practitioners.
Massage clients often present with muscle spasm, painful trigger points, and limited range of motion (ROM). MET may be used during a massage session to enhance outcomes of improved mobility and comfort for clients.
Evidence-based research indicates the value of MET in improving flexibility in clients of all ages, including rehab clients and the fragile elderly. Schiowitz reported that subjects with neck motion restrictions had a significant increase in cervical ROM after treatment with MET, as compared to a sham control group. Wilson et al. reported a significant improvement in function and decrease in disability in patients with low back pain treated with MET compared to those treated with traditional exercise and neuromuscular re-education alone. Contemporary muscle energy techniques are a part of interdisciplinary patient care, usually combined with manual therapy, massage and exercise.
There are various stretching approaches described by MET practitioners. Each approach has its benefits. Most utilize the effect of post-isometric stretching, in which the involved short muscle (the agonist) is isometrically resisted, followed by passive or active stretching of the agonist by activation of the antagonist and/or passive movement by the practitioner. In PNF, this is known as contract-relax and hold-relax. Two types of MET have been described: post-isometric relaxation (PIR) and reciprocal inhibition (RI).
In PIR, the short agonist muscle is activated with a gentle resisted isometric contraction for up to 10 seconds, followed by relaxation and passive stretching into the motion barrier within the tolerance of the client. The isometric contraction of the short agonist loads the proprioceptive Golgi tendon organ (GTO) within the agonist, causing a reflexive relaxation of the muscle. (GTOs inhibit contraction via the Ib afferent fibers to the spinal cord and efferent motor neuron.) After an active contraction, there is a short latency period within which the short agonist is inhibited. In physiology, this is called the refractory period, which lasts about 15 seconds.
Activation of the long antagonist also inhibits the short agonist by reciprocal inhibition. For example: When the flexors are activated, there is an automatic inhibition of the extensors by reflex action at the spinal cord level. It is useful to activate the antagonist during the stretch to take advantage of the relaxation response of reciprocal inhibition. Exhalation is often used during the stretching period to enhance the relaxation effect. If the client activates the long antagonist, the effect of the short agonist's stretch reflex will also be reduced. The combination yields a significant increase in the length of the agonist.
Key features of effective MET stretches are the use of precise control of the joint being moved, specific resistance intensity to avoid damaging the muscle being stretched, and accurate timing of the stretch to begin after the short muscle has relaxed. MET has been shown to be effective in reducing hypertonicity, increasing ROM, and decreasing disability and pain.
The literature reflects that experts use different variations of MET. McAtee and Charland described the use of strong resisted isometric contractions, followed by active stretching by the client, typically in diagonal patterns.
One must be cautious when using strong contractions to avoid damaging the muscle, especially after an injury. Gentler contraction forces are considered safer. PNF uses varying intensities of contraction followed by passive or assisted stretching, using both diagonal and straight arc patterns of motion. AIS uses breathing with repeated (1-2 seconds) isotonic contractions of the antagonist followed by patient-assisted stretching, exhaling while moving the joint through the barrier for 1-2 seconds and returning to neutral. Caution must be used to avoid stretching too rapidly when using short-duration contractions in severely involved individuals.
Goodridge and Kuchera recommend using low-intensity isometric contraction followed by passive stretching to minimize muscle guarding and delayed onset muscle soreness.
Each practitioner must determine the best method for their client based on the clinical presentation, type of restriction, tolerance of the client and desired outcome. With muscle guarding, simple PIR is effective to reduce contractile hypertonicity. With myofascial restrictions, additional passive stretching through the motion barrier is used and held for 90 seconds to allow the noncontractile tissue to lengthen. In most cases, forceful or ballistic stretching is avoided to reduce the incidence of microtrauma in the involved muscle.
To summarize, the steps to perform basic post-isometric relaxation MET with reciprocal inhibition are as follows:
1. Position short muscle into a stretch or point of motion barrier.
2. Ask client to use 10 percent to 30 percent intensity isometric contraction of the short muscle against your resistance.
3. Hold isometric contraction 3-10 seconds with a brief rest period of 2-3 seconds.
4. Provide passive or active assistive stretch, a bit beyond the resistance barrier within the tolerance of the client.
5. Practitioner may then ask client to activate the antagonist to move beyond the barrier into the greater ROM.
6. Perform three to five repetitions of the activity and reassess the ROM, pain level and function.
Massage clients often present with muscle spasm, painful trigger points, and limited range of motion (ROM). MET may be used during a massage session to enhance outcomes of improved mobility and comfort for clients.
Evidence-based research indicates the value of MET in improving flexibility in clients of all ages, including rehab clients and the fragile elderly. Schiowitz reported that subjects with neck motion restrictions had a significant increase in cervical ROM after treatment with MET, as compared to a sham control group. Wilson et al. reported a significant improvement in function and decrease in disability in patients with low back pain treated with MET compared to those treated with traditional exercise and neuromuscular re-education alone. Contemporary muscle energy techniques are a part of interdisciplinary patient care, usually combined with manual therapy, massage and exercise.
There are various stretching approaches described by MET practitioners. Each approach has its benefits. Most utilize the effect of post-isometric stretching, in which the involved short muscle (the agonist) is isometrically resisted, followed by passive or active stretching of the agonist by activation of the antagonist and/or passive movement by the practitioner. In PNF, this is known as contract-relax and hold-relax. Two types of MET have been described: post-isometric relaxation (PIR) and reciprocal inhibition (RI).
In PIR, the short agonist muscle is activated with a gentle resisted isometric contraction for up to 10 seconds, followed by relaxation and passive stretching into the motion barrier within the tolerance of the client. The isometric contraction of the short agonist loads the proprioceptive Golgi tendon organ (GTO) within the agonist, causing a reflexive relaxation of the muscle. (GTOs inhibit contraction via the Ib afferent fibers to the spinal cord and efferent motor neuron.) After an active contraction, there is a short latency period within which the short agonist is inhibited. In physiology, this is called the refractory period, which lasts about 15 seconds.
Activation of the long antagonist also inhibits the short agonist by reciprocal inhibition. For example: When the flexors are activated, there is an automatic inhibition of the extensors by reflex action at the spinal cord level. It is useful to activate the antagonist during the stretch to take advantage of the relaxation response of reciprocal inhibition. Exhalation is often used during the stretching period to enhance the relaxation effect. If the client activates the long antagonist, the effect of the short agonist's stretch reflex will also be reduced. The combination yields a significant increase in the length of the agonist.
Key features of effective MET stretches are the use of precise control of the joint being moved, specific resistance intensity to avoid damaging the muscle being stretched, and accurate timing of the stretch to begin after the short muscle has relaxed. MET has been shown to be effective in reducing hypertonicity, increasing ROM, and decreasing disability and pain.
The literature reflects that experts use different variations of MET. McAtee and Charland described the use of strong resisted isometric contractions, followed by active stretching by the client, typically in diagonal patterns.
One must be cautious when using strong contractions to avoid damaging the muscle, especially after an injury. Gentler contraction forces are considered safer. PNF uses varying intensities of contraction followed by passive or assisted stretching, using both diagonal and straight arc patterns of motion. AIS uses breathing with repeated (1-2 seconds) isotonic contractions of the antagonist followed by patient-assisted stretching, exhaling while moving the joint through the barrier for 1-2 seconds and returning to neutral. Caution must be used to avoid stretching too rapidly when using short-duration contractions in severely involved individuals.
Goodridge and Kuchera recommend using low-intensity isometric contraction followed by passive stretching to minimize muscle guarding and delayed onset muscle soreness.
Each practitioner must determine the best method for their client based on the clinical presentation, type of restriction, tolerance of the client and desired outcome. With muscle guarding, simple PIR is effective to reduce contractile hypertonicity. With myofascial restrictions, additional passive stretching through the motion barrier is used and held for 90 seconds to allow the noncontractile tissue to lengthen. In most cases, forceful or ballistic stretching is avoided to reduce the incidence of microtrauma in the involved muscle.
To summarize, the steps to perform basic post-isometric relaxation MET with reciprocal inhibition are as follows:
1. Position short muscle into a stretch or point of motion barrier.
2. Ask client to use 10 percent to 30 percent intensity isometric contraction of the short muscle against your resistance.
3. Hold isometric contraction 3-10 seconds with a brief rest period of 2-3 seconds.
4. Provide passive or active assistive stretch, a bit beyond the resistance barrier within the tolerance of the client.
5. Practitioner may then ask client to activate the antagonist to move beyond the barrier into the greater ROM.
6. Perform three to five repetitions of the activity and reassess the ROM, pain level and function.
