Having a tight muscle almost always translates into joint stiffness. Back in the days, Osteopaths developed a clever technique of restoring a muscle’s ‘normal’ length to prepare clients for joint manipulation. Once the surrounding soft tissues are sufficiently released, the chances of comfortable and successful joint manipulation are much higher.
The Muscle Energy Technique (MET) affects beneficial change for the client by using the energy of their own contracting muscles. It “targets the soft tissues primarily, although it also makes a major contribution toward joint mobilisation” (Chaitow, 1996, p1).
MET can be used as a standalone technique or intelligently integrated into a complete soft tissue session that includes other techniques as well. Muscles tend to respond far better to MET once they’ve been warmed up with massage. Additionally, this would have allowed the therapist to identify tight areas that are likely to need more attention.
MET aims to restore the ‘normal’ length of tight, hypertonic muscles and address areas of scarring or adhesions. As such, it does not attempt to increase muscle length beyond what is normal and functional for the individual but merely to restore. This means that they only work where there is a real and noticeable restriction in the tissues.
MET helps restore the tone of the muscle by using its innate capacity to contract and relax. It also helps strengthen the treated muscle by restoring its normal length and thus increasing its contractile potential. By normalising muscle length, it is an effective preparation for further stretching. MET increases joint mobility by normalising the length and tone of the surrounding soft tissues. It also boosts local circulation and improves musculoskeletal functioning in general.
Although the effects of MET are quick and dramatic, it is recommended to maintain and/or continue the progress by incorporating regular stretching.
How MET works
All muscle energy techniques are based on two different phenomena occurring in the neuromuscular system that promote a temporary relaxation response.
Post Isometric Relaxation is the first key phenomena enabling MET. “Following a [6-8 second] isometric contraction … there is a refractory, or latency period of approximately 15 seconds during which there can be an easier movement (lengthening) towards the new position of a joint or muscle” (Chaitow, 1996, p5). After the isometric contraction, the muscle becomes inhibited and more relaxed and can be more easily stretched to a new resting length.
Experience shows that a very mild contraction with 5-20% of one’s strength is absolutely sufficient and more effective than a stronger one at achieving the desired outcome.
The PIR manoeuvre involves the following steps:
This manoeuvre is possible due to the inverse stretch reflex which causes the muscle to relax. It is mediated by the Golgi Tendon Organs (GTOs) that monitor the load on the tendon. They would cause the muscle to relax through neurological inhibition once a certain load threshold is reached. This reduces the risk of muscle tear during contraction.
It is worth noting and remembering that the PIR technique is not to be used with muscles that are recovering from a recent trauma. It can be overwhelming for the recovering fibres and cause them to re-tear.
Reciprocal Inhibition (RI) is based on the agonist/antagonist muscle relationship. When a muscle contracts, the one opposing it will relax through an automatic inhibition. This effect enables the comfortable lengthening of a tight hypertonic muscle by contracting the one opposing it.
Unlike, PIR, in RI the lengthening needs to occur simultaneously with the contraction of the opposing muscle because as soon as it stops the effect is lost.
There are two basic methods of using RI to good effect.
RI is triggered by using the body’s stretch reflexes. A myotatic stretch reflex, for example, prevents lengthening the muscle too quickly or too far. Proprioceptors in the muscles known as muscle spindle cells monitor the rate of change in length and tension in the muscle. When a threshold is reached, they will cause a spontaneous contraction in the muscle to prevent over stretching.
Especially the active RI is safer in treating gentler areas like the neck or when working with clients after recent injuries. This is because the client has greater control and the body’s natural preservation reflexes are likely to stop them before causing any damage.
A healthy antagonist can be contracted in a reasonably shortened position to enable the stretch of the target muscle. Care is needed here to avoid a spasm when contracting an already shortened muscle. This is one of the potential limitations of the active RI method.
Combining PIR with RI
The two methods can be combined in order to produce a very quick and effective muscle lengthening. When used jointly they usually yield the maximum achievable result for the session with just one repetition.
This combined approach is hugely effective but it requires a very clear and precise communication so that the client can comply with the instructions.
MET can be an invaluable tool in the arsenal of a soft tissue therapist relieving clients' discomfort safely and effectively.