The Vault

Recent Physiological Research

Into The Alexander Technique
 

Dr David Garlick,
School of Physiology & Pharmacology University of New South Wales, Sydney.

 

In developing an appreciation of wine, it is said that the person is 'educating' her/his palate. The senses of taste and smell are being trained or educated to be able to discern the characteristics of wine. While the analogy is only a passing one, it can be said that the Alexander Technique (AT) is partly about training or educating the proprioceptive sense to become more sensitive and discerning to proprioceptive or kinaesthetic inputs.

I think it has been a wise approach to describe the Technique as an educative one, in terms of educating the senses. It means the Technique is not setting out primarily to be a therapy for people with health problems with all the implications this can mean for the Technique and the teaching of it. It is an education, or more precisely a re-education, of the proprioceptive sense associated with changes to motor programs for muscle control in the individual person. Therapeutic benefits may well flow from such re-education, as a by-product.

Overall, the Technique can be described as psychomotor re-education of the individual person. It is essentially a physiological technique associated with important psychological effects. This is why the AT has attracted me over the years, not only for its very useful effects on my own psychomotor functioning, but also because it can be related to many physiological mechanisms. It also, as with other empirically based observations, suggests connections and hypotheses that would otherwise not have been considered.

These are two areas I want to deal with; namely, some interesting (known) physiological mechanisms and some hypotheses I have developed to be tested in relation to the AT.

Parenthetically, can I make the plea that more time be given to teaching physiology, and not just anatomy, in the theory sessions of training programs. Structure is important but function is what the AT is about and function is physiology. Function may be quite different to what structure may lead one to expect. Consideration of building materials does not really give one a good idea about the functions of a building.

Physiological Mechanisms

The sense of body position is a function of the saccule and utricle of the inner ear, which sense the position of the head with respect to gravity, and the inputs from receptors of the body (skin and muscle); receptors such as skin pressure receptors which indicate there is pressure on the soles of the feet, or pressure on the buttocks when sitting.

One's position, however, is never static (even when asleep). When sitting, a person shifts to relieve pressure on the buttocks and ischial tuberosities; when standing, one sways in a rhythmic fashion.

To detect movement there are receptors that respond dynamically. Those in the inner ear are located in the semicircular canals where movement of the head, particularly rotatory movement, results in movement of the fluid in the canals which stimulates receptors there. Sway of the body means transient stretching of muscles and this, of course, stimulates those complex receptors of the muscle spindles which are so sensitive to stretch and which activate a simple reflex to contract muscles to counteract the stretch. Muscle spindles are complex because they contain at least three different receptors responding to different stimuli and they have their own motor nerve which can make the spindle more or less sensitive to stretch.

This last observation is quite intriguing in relation to the AT. Muscle spindles can be made more or less sensitive by their own motor nerves (gamma motor nerve fibres), because muscle spindles have their own tiny muscle fibres which can shorten or relax depending on the activity of their gamma motor fibres. Interestingly, spindles seem to be located in relation to red muscle fibres, part of which are the postural fibres which are located in calf, thigh, back and neck muscles. Is the 'energising'—or making more 'alive' or getting the muscles to 'work' appropriately—of a person's muscles, during AT lessons, so that the person's 'use' improves, related to activating the gamma fibres which sensitise the spindles which then become more active so that postural muscle fibres undertake more of their anti-gravity, supporting function and relieve other muscles of having to do this? This is an hypothesis that will have to wait to be tested.

How are the inputs from these receptors handled by the brain? A fair generalisation of the brain (that is, the conscious part, which is what is of most concern to us in everyday matters) is to say that it is designed to be free of inputs from the body. These are handled at sub-conscious levels. So, unless something extreme happens, such as when we really tilt over, we are not aware of proprioceptive inputs, so that the conscious brain (mind) is freed. The problem with this is that a person's program for posture may be an inadequate one (habitually stooped or 'pulled down' or using over-contraction of muscles in various regions or 'collapsed') but, for that person, it is perfectly normal and accepted by the subconscious centres as the norm. The muscle contractions for a person's posture may, and usually are, inappropriate, but the sensory or proprioceptive inputs say everything is normal.

Hence F.M. Alexander's dictum that the sense of a person's 'use' of her/his muscles is debauched or it cannot be trusted. The sensory inputs for the person's normal posture and movements are taken as normal for that person. It takes conscious attention to get these subconscious inputs to consciousness for the person to begin to realise that muscles are overcontracted or, as with the back muscles, may not be contracting or 'working' enough.

Muscle Fibres

One standard description of muscle fibres is that there are three types; namely, red, intermediate and white. A classification I have suggested is more a functional one; namely, red postural fibres, intermediate rhythmic fibres, and white strength fibres.

The red postural fibres are the lowest in strength and are the ones first to be activated when a person changes from a resting supine position to an upright position. Intermediate rhythmic fibres are, as the term implies, the ones used for rhythmic activity as in walking, jogging, cycling, swimming. Both of these fibre types are, theoretically, non-fatigable provided there is a constant supply of oxygen supplied by the circulation and from which the muscles' waste products are carbon dioxide and water. The white fibres are called upon when one has to exert oneself, when a sense of effort is required. They are fatigable; one can't keep on holding or lifting the weight or sprinting, etc. They are fatigable because they do not use oxygen but use a lot of glycogen (muscle storage form of glucose) and produce lactic acid with which is associated a sense of fatigue and tiredness.

An important feature of these two types of red fibres is that "if you don't use them you lose them". For instance, for the red rhythmic fibres if they are not used sufficiently and frequently enough in rhythmic activity, then they lose some of their metabolic features. Red fibres are an important locus for the uptake of blood sugar. A sedentary individual will have poor sensitivity to insulin's action on her/his rhythmic red fibres; hence a poor uptake of blood sugar. If the person has an hereditary tendency towards diabetes, then the effect of insufficient activity of their rhythmic red fibres will lead to the development of diabetes. Rhythmic red fibres are also important for using fatty acids from the fat stores. This is how fat is burnt. If these fibres are under-used, fat will not be burnt up so much and fat accumulates. Another interesting effect that adequate rhythmic activity can have is on decreasing the activity of the sympathetic nervous system (part of the autonomic nervous system or the 'automatic' nervous system that maintains the functioning of the circulation, respiration and digestion.)

Adequate activity for the postural red fibres is also essential. A striking feature of an effect of space flight with its absence of gravitational effect is that red postural fibres lose their ability to maintain a person upright on return to earth's gravity (although preventative exercise can mitigate some of this effect). These red fibres lose some of their mechanisms and actually become more like white fibres.

Here is another hypothesis to be tested; that the person with poor 'use', with poor posture, with inadequate activation of back muscles to support the trunk will have red fibres no longer capable of adequately subserving postural support of the trunk so that other trunk muscles, including those normally used for respiration, will have to be brought into play. Testing a sample of these former postural red fibres should reveal that they have changed their characteristics.

This is an experiment I hope I and others can carry out since we have already taken small samples of athletes' muscles to look at their muscle fibre types.

Brain Control of Muscle

F.M. Alexander's twin diagnosis of the postural problem of the human condition was that of faulty awareness (subconscious sensory inputs accepted into the person's subcortical programs as normal despite these being inappropriate) and poor 'use'.

'Use', of course, refers to how a person uses her/his muscles for posture and movement. The brain controls muscles in posture and movement in very complex mechanisms, but it is possible to make several generalisations. Normal posture is based on reflexes and these are subcortical and hence subconscious. Repetitive and skilled movements are laid down as subconscious, subcortical programs. The conscious mind is involved only when the movement is unusual or is being learnt.

A feature of these programs for muscle activity for posture and movement is that it must be carried out in definite patterns and sequences, of which muscles and in what sequence muscle activity is to occur. Red postural fibres, the easiest to activate, must be engaged to set the body for whatever the action is going to be. The action (sitting, standing, moving a limb) requires activating muscles in a definite order. If a muscle or a muscle group is not functioning properly (for instance, it is over- or under-contracted) then the pattern, as well as the sequence, will be affected. For instance, if the red postural fibres of the back have been under-used and become altered or atrophied, then the program for sitting or standing will be altered to compensate for this and it will need to activate other trunk muscles, abdominal and chest, to assist.

It is pertinent to refer to FM's insistence on looking at the whole person and not a part. As he would put it, if a person's use was defective in one part then her/his use overall would be defective. This is certainly borne out in the subcortical programs for motor control.

The left side indicates that the environment can provide a lot of 'bits' of information (billions per second) via the eyes, ears and touch. Only a very small proportion of these (10 to 100 bits per second) are recognised in terms of entering consciousness. The billions not entering consciousness are processed subconsciously. From this input is generated a lot (billions of bits of responses per second) of outputs in the form of speech, facial and bodily expression and actions such as with the hands.

(From Colour Atlas of Physiology, by A. Despopolous & S. Silbernagl, 4th edition, Georg Thieme Stuttgart: 1991.)

Experiments

This brings me to experiments that we have carried out in regard to trunk muscles and which I have described before. Standing subjects had the electrical activity of their back muscles measured and, at the same time, their respiratory abdominal movements were measured.

Abdominal respiratory movements are a useful measure of abdominal muscular tension, with which is associated chest muscle tension. The greater the tension of the abdominal muscles, the less the abdominal respiratory movements. The respiratory movements become less and become more frequent; that is, the person breathes more shallowly and more frequently.

We found that a person with higher back muscle activity had greater abdominal respiratory movements and these were at a lower frequency; the person with lower back muscle activity had conversely less abdominal respiratory movements and frequency was higher.

Thus, inadequate use of the red postural fibres of the back muscles leads to their 'atrophy'. The patterning of the subcortical programs then must compensate by bringing trunk support from other trunk muscles which normally subserve respiration. When these trunk respiratory muscles are engaged in supporting the trunk then their respiratory function is compromised and their respiratory movements are diminished.

A further set of experiments I hope we can undertake is to use a technique we have developed of inserting very fine wires into muscles to record the electrical activity of individual muscle fibres. We want to observe the electrical activity in deep back muscles (multifidus) and in other back and abdominal muscles in both Alexander-naive and Alexander-experienced subjects when they are sitting or standing when slumped or pulled down and when 'going up' or extending during an Alexander lesson.

BIOGRAPHY

David Garlick is a medical practitioner, Senior Lecturer in physiology and Director of Sporting Medicine Programmes at the University of New South Wales. He recently completed training as a teacher of the Alexander Technique.

 

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