What is meant by posture?
There have been many definitions and meanings attributed to the term posture including:
- "Posture is represented by theset of positions of all joints of the body at a certain time' (Kendall).
- "Posture means any attitude, defined by the relationships established between the various body segments, that we can assume in the space"(Boccardi).
- "Posture is somatic expression of emotions, impulses and regressions... unconscious reflection in the outward attitude of one's inner condition, one's personality' (Cailliet).
- "The upright posture is characteristic of man; it depends on the integrated activity of a whole series of coordinated reflex mechanisms that determine it, maintain it, restore it" (Houssay).
From all these statements it is possible to extrapolate the various aspects attributed to posture:
- Anatomical: as a structural expression of the postural attitude.
- Neurophysiological: as a purely neurological expression.
- Psycho-motor: as a somato-emotional expression.
Posture and applied kinesiology
It is easy, in fact, in common parlance, to associate posture with an exclusively anatomical-biomechanical meaning, which, undoubtedly, always has its importance, but we must also consider other aspects that in many cases represent the cause of that given postural attitude.
It is therefore necessary to consider the organism in its entirety, which can be represented, following the concept of the kinesiology trianglefrom the union of three fundamental components:
- morphological-structural
- biochemical-functional
- psychic-mental
Balance - imbalance / order - disorder: how posture works
Posture' therefore represents a delicate balancing act between a rigid structure (the skeleton), the stays (muscles and tendons) that support this structure and a control and regulation system (nervous system). The whole always represents a continuous change of shapes and positionsin connection with the biochemical-functional and psychological-mental component and in relation to environmental stimuli, in particular gravity.
The postural system, therefore, allows the body to maintain an upright position in relation to the force of gravity. The body, however, is in constant motion not only during walking, but also when stationaryas it is still subject to breathing, heartbeat and cranio-sacral movement.
What are postural muscles?
The upright position is maintained by a continuous alternation of contraction and relaxation of the so-called 'postural muscles', which allow one's centre of gravity to be kept within a space contained between the feet, defined 'support polygon'. The postural muscles are linked together in chains from the feet to the head and are controlled and regulated by the Postural Toning System.
The latter is constituted not only by the closed kinematic chains formed by the postural muscles, but also by the peripheral receptors and control mechanisms of the reticular system deputed to act as a filter for the body's automatic functions. This system is not under the control of the will, but reacts autonomously to the stimuli received. Subsequently, processing takes place in the higher centres (vestibular nuclei) and the cerebellum, to receive a finer and more complete response. Let us remember that the receptors that allow the control of posture are numerous. These include the skin receptors, the vestibular apparatus and the visual apparatus.
