posture and sport
of Prof.. Francesco Perrotta
The posture is represented by the positions of all the joints of the body in a certain time "(Kendall).
"With posture is any attitude, defined by the relationships established between the different body segments, we can take in space" (Boccardi).
"The posture can be seen all the existing relations between the whole body, the various parts of the body and the environment that surrounds him"
"The posture is somatic expression of emotions and impulses regressions ..... unconscious nell'atteggiamento outward reflection of his inner
condition, their personality" (Cailliet).
"The posture is a comprehensive settlement of a certain environment, a correlation between the physical and mental aspects of behavior"
"It sets the posture that the body, or a component, thanks to assume ownership of passive ligaments and joints of the bonds and properties of active
muscles tonic, in harmony with the force of gravity" (Caradonna).
The posture then is the result of three fundamental aspects:
Then the three components of posture, generally integrated and overlapping, are:
1 posture mechanics
2 posture neurophysiological
3, the psychomotor posture.
It 'good to clarify that there is a posture but an infinite number of postures: they correspond to any position in balance. " When we talk about posture
we refer to an "idea", representing the structural and functional condition of the human body that allows the purchase of each "position" for the
performance of motor, static or dynamic, with the maximum balance (stability ), The largest economy (minimum energy consumption), the maximum
comfort (minimum stress on the anatomical structures).
In practice the posture is the way to stay in balance of the human body is that it stopped moving and that balance is the outcome of various structures
of the body: SNC, column, limbs and their interconnections with the outside world.
"Everyone has to take the body that has and use it as best he can. For each individual the best posture is one in which the body segments are
balanced in the position of minimum effort and maximum stability" (Metheny)
POSTURA: MATCHING AND BALANCE muscular.
The station built, which is characteristic of the human species, is one of those endless posture, characterized dall'allineamento in the vertical and
dall'appoggio two feet on the ground. It 'a posture entirely artificial, very rarely used in everyday life but there is nevertheless useful as a reference
position from which to derive more natural posture with its symmetry and some biomechanical properties easily definable (Boccardi).
Indeed sides skeletal rely on foot and supported by tension in balance "passive" of the ligaments from aponeurosi and elastic properties of muscles,
as well as a small contraction "active" drive motor in particular stabilizing muscles. (Daniels)
"...... among mammals is that the man who owns the mechanisms antigravitari cheaper, upon reaching the station built. On the energy muscle for
what seems a rather clumsy is actually very economic "( Basmajan).
The station erected symmetrical relaxed, also of the joints, as well as those of the knees, take a position as full extension must bear the weight above.
In the ankle there is no limit to the bone or legamentoso movement, as happens at the knee, however the passive tension of biarticolarità muscle
gastrocnemial is an important factor for stability until the knee is extended and body tilted slightly forward of the ankles.
1 - Posture standard
In the standard posture, this column presents curves in standard and the bones of the lower limbs have a perfect alignment to support the weight
leading to a small amount of tension and contracture and running at maximum efficiency of the body.
The thorax and the dorsal region are in a position that promotes optimal function of the organs of respiration.
The head is erect in a position well balanced, so that allowed the slightest tension borne by the muscles of the neck.
a-normal curves of the column.
The normal curve of the column consist of:
A - Lordos cervical: convex curve before cervical level of about 35 °
B - dorsal kyphosis: convex curve in the region after the upper back (thoracic region) of about 36 °
C - Lordos lumbar: convex curve before the bottom of the back (lumbar region) of about 50 degrees. (Boccardi)
The upright can be regarded as the alignment of the subject composite of four sides: front, rear, right side and left side. It appears unlikely that a
person meets every aspect of the standard.
b-Developing physiological curvature of the spine.
The curvature of the spine has been significant changes in the process of adaptation and phylogenetic ontogenetico in humans and primates.
Phylogeny in the transition from a walking from four to two supports is inevitably accompanied a change in the initial lumbar kyphosis, the first in a
straightening and proceed with the development, in achieving a true reversal of the curvature of departure ( Lordos lumbar).
The balance of full erection of the trunk has happened over time thanks all'inclinazione back of the pelvis which in turn affects the severity of the
Regarding the ontogeny is known that the position of intrauterine fetal body is characterized by a decline of the whole spine (kyphosis strong).
This posture is maintained for a certain period of time after birth, but from the 6 ^ ^ -8 week of extra-uterine life, the child begins to extend the neck
lying in the prone position and, in so doing, put in operation the back of the neck muscles that, in doing so, contrasts the action of the force of gravity.
In a later period, the child, assuming a sitting position, always a great lumbar kyphosis associated with cervical Lordos. In this situation he learns to
control the weight of the head with the musculature is placed above the girdle.
Only then will form the lumbar Lordos, that is when it starts to make the first attempts to stay upright and then to walk. It reaches the final position
orthostatic occurs when the curvature of the foot.
The concept of the "orthopedic" implies, in fact, a straight posture of the body that is the result of proper performance of the three physiological
curve of the spine and adding the right curvature of the plant foot. (Rocabado)
2 - skeletal alignment (Boccardi).
In station erected segments are aligned almost like anatomical position, with his head high and walk supported on the ground. The segments are
attitude by the major axis vertical, two horizontal feet. The palms of the hands look inward.
The joints are almost all in position 0 or departure and are thus defined nell'atteggiamento station standing with arms aligned to the sides and palms
of hands facing forward (anatomical location). The tibio Tarsicio are lightweight dorsal flexion (2 ° -4 °), even in light of the extension. The medial
rotation at 90 ° upper bearing the palm of the hand to look inwards, is divided between internal rotation of the arm, (about 30 °) and the return of
supine dell'avambraccio (about 60 ° ).
a-Alignment ideal to lead: side-view.
Examining the upright posture in the station you use a plumb line as reference (plumb line). You use this tool because it represents a standard that is
based on the natural law of gravity and allows us simply to appreciate the effects of this force. The point at which it is placed in the wire must be a
fixed standard and seen this side of reference is slightly earlier than the external malleolus and represents the point at the base of the coronal plane
of the body in perfect alignment.
Kendall 90 'upright posture describes as ideal one in which the plumb line through the following points (points of reference surface and brackets
anatomical structures that coincide with the reference line):
• 1 slightly earlier than the lateral malleolus (through the articulation calcaneo cuboide)
• 2 slightly earlier than the midline of the knee (slightly relative to the front of the knee)
• 3 about through the great trochanter of the femur (slightly back to the center of the articulation joints)
• 4 about halfway through the trunk (the bodies of lumbar vertebrae)
• 5 through the articulation of the shoulder
• 6 bodies of most cervical vertebrae (through the process of the odontoide)
• 7 through the earlobe (external auditory meatus)
• 8 (slightly later than at the height of coronal suture) in adults arrow lumbar must be 4 to 6 cm, and the arrow cervical 6 to 8 cm. (Bricot)
b-Alignment segmental ideal: side-view.
We look for segments of the alignment in a side-view. The head is in neutral position, not tilted forward or back. The column presents a cervical curve
in accordance slightly convex before (about 35 °).
The blades are flat against the back and well aligned.
The thoracic curve is normal after slightly convex.
The basin is in neutral position that is the spine anterior-upper on the same vertical plane of the symphysis pubis.
The hip implants is in neutral position, namely the longitudinal axis of the basin (conventionally referred to as the perpendicular drawn from the
great trochanter, apex, the line connecting anterior iliac spine-top, SIAS, iliac spine and upper posters, SIPS) should form an angle of 170 ° forward
with the long axis of the thigh. Neither flesse or extended.
The joints of the knees are in neutral position, nor flesse or hyperesthesia. The leg is extended directly to the thigh. In this position, there is no
possibility to change the relations of the two body segments in both frontal plane than in the horizontal.
The ankle joints are in neutral position, ie the longitudinal leg form an angle of 90 degrees with the plan of support.
c-Alignment ideal to lead: rear vision.
Looking at the station built, rear view, the fixed point of reference is located halfway between the heels and represents the point of the medium-
sagittal plane of the body in perfect alignment which has the second Kendall, when the line extends lead in starting a half distance between the two
beads, up to half way between the legs and across the midline of the basin, the column, sternum and skull.
Half right and left of the skeletal structure are essentially symmetrical and it is assumed that the two halves of the body balance is so precise.
More precisely aligned in perfect view to the rear is when a plumb line passes exactly:
1 between the Calcagni
• 2 crosses the remaining inter-gluteal
• 3 the sacred
• 4 VII cervical (C7)
• 5 the occipital protuberance
d-Alignment segmental perfect vision back.
We observe alignment for segments in a rear vision.
The head is in neutral position, neither inclined nor rotated
The cervical column is straight.
The blades are staying neutral media margins are substantially parallel and spaced about 7-10 cm.
The thoracic and lumbar spine are straight.
The hip joints are in neutral position, neither invoked nor abdotte.
The legs are straight, not arcuati or with valgismo.
The feet are parallel or slightly divaricata. The beads are spaced about 7 cm. The external malleolus and the outer edge of the foot are on the same
plane so that the foot is neither in nor pronazione in supine. The Achilles tendon should be vertical. The basin is horizontal, both iliac spine poster
above are on the same horizontal plane.
e-Alignment Ideal frontal vision.
In this vision should be different horizontal lines:
• 1 line bi-pupillare
• 2 line bi-tragalica
• 3-line bi mamillare
• 4 line bi-stiloidea
• 5 line bi-scapular
• 6 pelvic belt line bi-SIAS
In addition, the rotule are addressed directly forward and feet are neither Proni or supine
3 - Balance muscle.
We said that good posture is that state of muscular and skeletal balance that protects the structures of the body from an injury or a progressive
deformity despite the position (standing, lying, accovacciata, china) in which these structures are working or oppose resistance.
Under these conditions the muscles work more effectively.
So a good muscle balance must ensure proper alignment and avoiding excessive contractures of joints, ligaments and muscles.
E 'necessary for this purpose that:
1, the muscle length of individual muscles allow a normal range of motion for each articulation;
2, the muscular, expressed by individual muscles or muscle groups, is the right (like intensity) in motor task before us, providing stability and support.
(Kendall) These two elements together are behind the preservation of good body mechanics in posture and movement.
The station built is cheaper in other mammals, which must always based on four limbs, joints but have more or less flesse that require an ongoing
effort muscle. (Basmajian)
E 'own arrangement of segments in humans, however, which makes the station built a highly effective mechanical and extreme economy.
a-vis muscle balance perfect alignment seen opposite.
Viewed from the side, the front and rear muscles inserted to maintain the basin in perfect alignment.
Before the abdominal muscles (m.obliquo outside of your m.retto) pull up and flexor implants (m. ileum-psoas, m. of tensor fascia lata, m. right
femoral) down; after pulling muscles back up and extenders implants (m.grande buttock, m. Biceps femoral, m. semimembranoso, semitendinoso
Consequently, the front abdominal and extenders implants work together after tilting the pelvis, the muscles of the lumbar region and the flexor
implants act together before tilting the pelvis.
The rear leg muscles are affected as the line of gravity moves to the front of tibiotarsica So the weight of the body applied at the center of gravity is
balanced by the strength of plantar flexor, although on the role of the sun and the gastrocnemial Opinions are not yet agree. (Boccardi)
"....... it can be said that the position of the basin is a key to postural alignment correct or incorrect. The muscles that maintain a proper alignment of
the basin, both in direction anterolateral rear side that are very important in Maintaining a good general alignment. An imbalance between the
muscles carrying an antagonist upright, changing the alignment of the basin and has a negative impact on the posture of the body parts above or
below. " (Kendall)
b-balance muscle ratio in perfect alignment seen from behind.
For the attitude of symmetry in the upright posture of the conservation plan on the front and less expensive than on sagittal plane.
The gravity tends to be divaricata limbs to bring down the center of gravity.
The friction offered by the land and its usual coatings is sufficient to prevent the abduction of the thighs.
Then walk to set the movement side of the basin, which involve even a modest lowering of the center of gravity, involving four simultaneous angular
1, the external rotation of the foot and the implants adducting side to which the basin moves
2, the internal rotation of the foot and the abduction of implants side.
E 'and then just alternate the game and cross the four opposing muscle groups (tibial and buttocks side of the first side, and peronei adductor of the
second) to correct the fluctuations in this sense. (Boccardi)
Let's see what are the stabilizing muscles to the right and left. (Kendall)
Stabilizing muscles to the right
• 1 flexor side of the trunk right-m. loins of square-m. internal oblique-m. external oblique
• 2 implants right adductor
• 3 abduttori implants claims-m. buttock medium-m.tensore fascia lata of stretch-ileum tibial fascia lata of
• 4-m.tibiale internal rotators rear right-m.flessore long dell'alluce right-m.flessore long fingers of right hand
• 5-m.peroneo external rotators long and short of the left
Stabilizing muscles to the left.
• 1 flexor side of the trunk of the left-m. loins of square-m. external oblique-m. internal oblique
• 2 adductor implants claims
• 3 abduttori implants right-m. buttock medium-m. of tensor fascia lata-section of the ileum tibial fascia lata
• 4-m internal rotators. tibial posterire left-m. Flexor dell'alluce along the left-m.flessore long fingers of the left
• 5-m.peroneo external rotators long and short of right
4 - Posture and CG
Each mass or body is composed of a multitude of small particles attracted to the earth as describing the force of gravity.
This attraction, which are particles of the body, produces a system of forces and virtually parallel the result of these forces acting vertically
downward, is the weight of the body. E 'can locate a point where you can apply a single force that is equivalent to intensity, the weight of the body
and acting vertically upward, so as to give the body balance in any position.
This point is the center of gravity and center of gravity and can be described as the point where you think it is concentrated around the weight of the
The CG is the exact center of mass of a subject, namely its "geometric center" when that object has a mass symmetrically distributed and is
homogeneous. If the mass as in the human body, is asymmetrically distributed in relation to the horizontal plane, the CG will be placed in proportion
to the area nearest larger and heavier.
With a posture in which the alignment is ideal and in an adult medium size, the center of gravity is to be placed in a slightly earlier than the spine at
the L3 (Wirhed) and about 56% of the total of 'individual from the ground. (Pirola)
However, the center of gravity can vary from person to person based on the distribution of weight to his height, age and sex: the woman is the lowest,
while the infant is higher. The position of center of gravity varies with shifts of body position.
If anatomical position in the center of gravity is about 100 cm above the ground, the lifting of the arm lifts of about 4 cm, to both arms of 8 cm, the
stand on tiptoe to 8 cm, and so forth. ..... so we have "several" centers of gravity.
Wirhed describes the position of center of gravity in the different body segments and its distance from the two ends of each segment as a percentage
of the total length.
For example, the center of gravity measured upper shoulders low, is at a point distant from the proximal about 40% of the total length dell'arto same.
Recall also that the center of gravity of two segments is always on the line joining the centers of gravity of these segments, namely at a point which is
in a position compared to centers of gravity of the two segments but proportionately closer to the center seriousness of the segment most heavy.
In erect posture, if it prolongs the vertical line, line of gravity, from the center of gravity to the base of support is going to put in the middle of the
base of support (given by a polygon almost trapezoidal shape formed by the side profile of the feet and the two lines which are respectively the front
and rear feet), 3 cm in front articles of the ankle.
Then the line of gravity passes on the sagittal plane about halfway between the tibio-Tarsicio and metatarsal-falangea and at front in supporting
well-distributed between both feet.
Around the seriousness of the body is hypothetically in a position of balance that involves a uniform distribution of body weight and a stable position
of each articulation.
For some principles of static learn that there are two types of balance:
- A static equilibrium
- A dynamic balance
The static balance is the ability of an object or a segment of the body or body as a whole, to maintain a static position.
The dynamic balance is the ability to maintain, during the various activities of life, the body segments in a stable condition.
The stability of a body is determined by several factors that divide in primary and secondary (Pirola).
The main factors are:
-height of center of gravity
-scale and form the base of support
-position on the line between seriousness and the cradle
-momentum of the body (mass x velocity).
The secondary factors are:
Guidance base of support compared to the line of force
conditions of the bond -
state of physical and emotional subject.
Then the body will be much more stable because the lower the height of its center of gravity compared to the subject.
Furthermore as the line of gravity will be put inside the polygon support the more stable will be the subject: in fact there are automatic postural
allowing the line of gravity always fall within the base of support in the event create movements of body segments after pe, to support loads.
5 - Mechanism of regulation of posture
The posture is registered in inner engine in the form of model and attitude from this scheme, once became conscious and internalized, you depart
adjustments of posture.
The s.n.c. regulates the movement patterns through engines or patterns in which the bones, joints muscles play the role of mechanical performers in
an all governed by laws of neurophysiology.
The patterns, patterns engines considered genetically determined and therefore innate heritage of the subject, because typical of the species listed in
its cells or groups of cells snow are intrinsic properties of the brain machine then in itself devoid of function.
But when the individual moves interacts with the outside world, offers its schemes engines and performs a continuous modulation afferences
esterocettive proprioceptive and organizing in the structuring of new schemes engines with functional features.
The development consists of normal motor learning patterns of engines increasingly selective and functional and this is possible thanks to the great
amount of information tactile, kinesthetic, sensory arriving at SNC during the execution of engines.
The s.n.c. controls posture and movement through a mechanism able to select from among the many possible combinations, a combination of muscles.
The posture can be considered as the risultane of a large number of sensory-motor reflexes integrated at various levels of neuraxis, with an automatic
adjustment extremely complex.
At this point we describe, in toto, the mechanism that regulates the posture and then analyze in greater detail the individual components.
The complex machinery that controls the attitude posture, both static and dynamic conditions, it can be shown under a system of automatic control
BLOCK 1 - are grouped centers superiors, including the brain, the cerebellum and the brainstem.
They get the information coming mainly from neuromuscular cast, bodies of Golgi tendon, and the retina from the skin and the labyrinth.
BLOCK 2 - is represented by interneurons, the motor alpha and gamma, in the spinal cord.
The signals direct to the motor, changing the length of the muscle may begin to move.
BLOCK 3 - includes muscle, but there may also be contained factors that affect its response contractility, namely the strength and load.
BLOCK 4 - includes propriocettori (merged neuromuscular, the Golgi tendon organs, the maze) and esterocettori (retina, skin receptors) because
they are all receptors that can affect posture.
The integration of impulses, from these different systems, is at the level of the brainstem.
The impaired functioning of a block or a connection between two blocks of the system causes a change in posture.
a-What the literature says?
In support of the descitto above, the literature we learn that:
....." Static positions are those in which the forces controlled by the central nervous system, forces muscle, are able to object to changes of relations
between the segments that external forces are trying to create, namely those where it is satisfied the necessary condition to maintain the balance: the
sum of the moments of forces is equal to 0. " (Scott)
"The upright posture is characteristic of man. It is integrated by a series of coordinated reflexes that determine the maintain the reconnect."
"The station built is a reflection (response) and postural large container in which was crucial to the contraction of muscles that antigravitari contrast
to the action of gravity that otherwise would cause the decline of the joints and the collapse of the body." (Sherrington, 1940)
Again, the posture can be interpreted as the result of the sum of reflections vestibule and cervical-spinal through the perception of the force of gravity
and the position of the head in space, activate the extensor muscles antigravitaria column and lower limbs to allow l 'attitude you want. (Gagey)
From a cybernetic, where the system is a set of structures between them and which interact to achieve a result, the posture is not a sum of reflexes,
but a 'interaction polisensoriale whose goal is the creation of a position In this case, the upright posture. (Gagey)
The neuromuscular system is involved in maintaining the station erected by intervening with corrective mechanisms because, in a relaxed, skeletal
segments are kept in balance by the symmetrical passive tension of the ligaments from aponeurosi and dall'elasticità muscle.
The function of the central nervous system, in maintaining the posture, is essentially to transfer pulses of different origin who are on spinal motor
nuclei and encefalici from which originate the efferenze that control the activity of the muscles responsible for maintaining posture.
The motor is capable of operating this integration already a segmental level.
The core of nuclear engines segmental level necessary to maintain the posture depends on the nerve impulses from different types of sensory
1) S. Boccardi, A. Lissoni, "Kinesiology" vol, II, III. Universe Publishing Company, Rome 1998
2) Bricot B., "The Reprogramming global posture," Statipro 1998
3) L. Bousquet, "The kinetic chain" vol. I Marrapese edition, Rome 1994
4) Daniels, Worthingham, "therapeutic exercises for the function and alignment of the body" Verducci Editor
5) Fleischmann, R. Linc, "Human Anatomy applied physical education and sport" vol.I, Sports Society Press, Roma 1981
6) Gagey p.m.. B. Weber, "Posturologia" Marrapese Editore, Rome 1988
7) J. Grieve, B. Tyldesley, muscles, nerves and movement, "Raphael Cortina Editore, Milan, 1991
8) A. Guyton, "Treaty of medical physiology," Piccin Editor, Padova 1978
9) Kapandji I. A., "Physiology articulate", vol. II, III, Marrapese Editore, Rome
10) Kendall, McCreary, Provanco, "The muscles," Verducci Editor, fourth edition, Rome 1997
11) V. Pirola, "The human movement," Edi Hermes, Milano 1998
12) Pivetta S., Pivetta M., "The foundations of medical gymnastics," Sperling & Kupfer Editori, Milano 1991
13) Testut L., Laterjeta. "Treaty of human anatomy," vol.I, UTET 1959
14) Tribastone F., "Compendium of corrective gymnastics," SSS, Rome 1985
15) D. Walter, "Applied Kinesiology," Systems DC 1988 Magazines and publications:
16) Proceedings of the first refresher course SIOS. Acts of Congress X Italian Academy of Kinesiology and electromyography Skull jaw, Alexandria
15-17 n0vembre 1996
17) P. Bracco, Deregibus A., Piscetta R., G. Ferrario, "Observation on the correlation between jow posture and position: a pilot study", Journal of
Craniomandibular Practice, vol. 6, No.4 October 1998
18) Bernkopf E., Broia V., Bertarini A., "Approach gnathology attitudes incorrect spine," The Modern Dental 4, 1996P.
19) Esposito G. M., J. Meersseman P., "Evaluation of the relationship between occlusion and posture," The Modern No Dentist 5, 923-941, 1988
20) Ferrario P., Sforza C., Schmitz JH, Taroni A., "Occlusion and center of foot pressure variation: is there a relationship?", J Prosther Dent 1996,
21) Naretto S.:corso di specializzazione Scienze Motorie,Torino; lezioni.
22) Pasteur F., "Scoliosi, squilibri posturali, piede: meccanismi di regolazione e loro correlazioni", XXXVIII Congresso Italiano della Società
Italiana di Ginnastica Medica, Albano Terme 23, 24 aprile 1994.
23) Rocabado M., "Quaderni del corso di aggionamento in odontoiatria", a cura di M. Bronchin, E. Brugnolo, Edizioni P.F.A.; Padova, 1989
24) Van Tichelen, D. Rousie Baudry" Cervicalgies secondaries aux desorders posturaux", La revue de Medecine Orthopedique n.42, dicembre 1995