Instructions for completing theoretical and methodological tasks
Quests are presented in the form of incomplete statements that may be either true or false when completed.
The statements are presented in:
Records must be legible.
Read the tasks and suggested answer options carefully. Try not to guess, but to logically justify your choice. Skip unfamiliar tasks instead of completing them by guessing. This will save time for other tasks. You can later return to the missed task.
Be careful when making notes on your answer sheet. Corrections and erasures are scored as an incorrect answer.
Each correct answer is worth 1 point.
THEORETICAL AND METHODOLOGICAL TASKS
Closed form assignments
1. The first All-Russian Olympiad was held in…
A. ... Nizhny Novgorod in 1907
b. ...Kyiv in 1913
V. ...Riga in 1914
...All-Russian Olympiads are not held
Answer: b
2. The supreme body of the Russian Olympic Committee (ROC) is...
A. ...ROC Bureau
b. …Executive committee
V. …Council of Species Federations
...Olympic Assembly
Answer: G
3. The main achievement of the First World Youth Games under the patronage of the International Olympic Committee, held in Moscow in July 1988, was that...
and...their medals went to 68 countries around the world
b. ...162 sets of awards were awarded at the games
V. ..young Russian athletes won 124 medals
...the program of the games included competitions in 15 Olympic sports
Answer: A
4. The theoretical material of the academic subject “Physical Education” in a comprehensive school includes...
A. …fundamental knowledge of a general theoretical nature
b. ...instructional and methodological knowledge
V. …knowledge about the rules for performing motor actions
g. ...all of the above
Answer: G
5. The specific subject of training in the process of physical education is...
A. …physical exercise
b. …facts, concepts, terms
V. ..regularities of biomechanics
d..motor actions
Answer: G
6. The ultimate goal of acquiring knowledge in the field of physical education is...
and….awareness of the need for physical improvement
b….forming readiness to use training samples
d..mastering physical exercises
d..applying them in practice
Answer: G
7. The specificity of physical education in relation to other types of education is...
A. …creating conditions for the processes of human physical development to take place
b. …teaching motor actions and developing physical qualities
V. …increasing human physical performance
g. …health promotion and disease prevention
Answer: b
8. The need to improve the physical capabilities of the human community has historically determined the formation...
A. …exercise
b. …physical education
V. …physical culture
...types of sports
Answer: V
9. Motor activity that stimulates the physical development of a person is designated as...
A. …improvement
b. …Physical Culture
V. …exercise
g. ...physical education
Answer: V
10. The “continuity” of physical education is characterized by...
A. …alternating activities of different directions
b. …by the interaction of exercise effects
V. ...a combination of physical exercises
g. ...lack of rest intervals
Answer: b
11. The healing effect of physical education is achieved as a result...
A. …ensuring full physical development
b. ...hardening and physiotherapeutic procedures
V. …formation of motor skills
g. ...improving the physique
Answer: A
12. The form of physical exercise is represented by...
A. …physiological and other changes in the body
b. ...kinematic characteristics
V. …internal and external structure
g. ...content
Answer: V
13. It is advisable to combine speed exercises with exercises “for...
A. ...coordination"
b. ...strength"
V. …endurance"
g. ...flexibility"
Answer: G
14. The basis of motor abilities is...
A. ...methods of teaching and education
b. …functional capabilities of the body
V. …strength, speed, endurance and flexibility
Answer: G
15. The basis for improving coordination abilities are methods...
A. ...development of physical qualities
b. …learning motor actions
V. ...strictly regulated exercises
d. ...use of contrasting and converging tasks
Answer: b
16. The applied orientation of physical education is emphasized in the concept...
A. … "physical training"
b. ... "physical culture"
V. ... "physical perfection"
G. …. "physical education"
Answer: A
17. The values created in the field of physical culture are not...
A. ...physical
b. ...intelligent
V. ...national
g. ...material
Answer: V
18. Basic physical education is most fully represented in...
A. …professional applied physical culture
b. ...the education system
V. ...adaptive physical education
...in school physical education
Answer: b
19. A healthy lifestyle is forms and methods of life aimed at...
A. …development of physical qualities of people
b. …optimization of physical condition
V. …preparation for professional activity
g. …maintaining high performance of people
Answer: b
20. A healthy lifestyle is...
A. … fulfillment of social, professional and biological functions by a person
b. ... “personal core”, which is the motivation for behavior
V. …activities to achieve a healthy lifestyle
g. ... an incentive for a healthy lifestyle
Answer: V
21. Functional changes in the body, recorded at the end of physical exercise, are usually referred to as...
A. ...training effect
b. …fatigue
V. ...under-recovery
g. ...operational status
Answer: A
22. Leading exercises used in the process of physical education are mainly aimed at…
A. …change in operational status
b. …formation of motor skills
V. …improving motor skills
d. ...achieving a certain level of development
Answer: b
23. To improve speed abilities, exercises are ineffective...
A. …helping to reduce body weight
b. …combined in the form of circuit training
V. …helping to increase frequency of movement
d. ...improving coordination abilities
Answer: A
24. At the stage of improving motor actions, methods are predominantly used...
A. ...standard-variable exercise
b. …standard-repetition exercise
V. …holistic-analytical impact
g. ...selective and conjugate influence
Answer: G
25. The basis of the methodology for teaching motor actions is to ensure...
A. …cyclicity of exercises
b. ...age adequacy of the load
V. …availability and individualization of the proposed tasks
d. ...gradually increasing the force of impact
Answer: V
26. The basis of the methodology for developing physical qualities is to ensure...
A. ...age adequacy of the load
b. …cyclicity of exercises
V. …gradually increasing the impact force
d. ...availability and individualization of the proposed tasks
Answer: V
27. When cultivating absolute strength, the most popular method is...
A. … repeated efforts
b. ...variable exercise
V. …circuit training
g. ... electrical stimulation
Answer: A
28. The amount of physical activity is a derivative of...
A. ...the number of repetitions of exercises and their duration
b. …speed, tempo and power of movements
V. ...its concentration over time
g. ...its volume and intensity
Answer: G
29. The number of repetitions at the stage of initial learning of movements...
A. ...usually approaching a re-maximum
b. ...should cause noticeable fatigue
V. …stimulates increased energy consumption
g. ...relatively small
Answer: G
30. Strength abilities themselves are characterized by...
A. ...the ratio of absolute strength to body weight
b. …the duration of the phases of tension and relaxation
V. ...the amount of maximum effort in an activity
g. ...by an impulse of force
Answer: A
31. People who systematically engage in physical exercise in combination with the use of the healing powers of nature are distinguished by... resilience.
A. ...phagocytic...
b......specific...
V. ...non-specific...
g. ...bactericidal...
Answer: V
32. The factor that primarily determines the manifestation of special endurance is the level of development...
A. …speed-strength abilities
b. …personal and mental qualities
V. …functional efficiency
g. ...anaerobic capacity
Answer: G
Open-ended tasks
Complete the statement by writing the appropriate word on the answer sheet
33. The system of measurements and research in anthropology of linear dimensions and other physical characteristics of the human body (height, mass, density, circumference, etc.) is designated as ...
Answer: Anthropometry
34. Maintaining the balance of the body by changing the position of its individual links is designated as...
Answer: Balancing (balancing)
35. The science of the manifestations of health, the patterns and mechanisms of its formation, preservation and strengthening is designated as...
Answer: Valeology
36. The red respiratory pigment of erythrocytes, which is involved in the transfer of oxygen from the respiratory organs to the tissues and carbon dioxide from the tissues to the respiratory organs, is designated as ...
Answer: Hemoglobin
37. The initial stage of a chess and checkers game, during which the opponents develop pieces (checkers) from the original position so as to give the desired character to the further course of the game, is designated as ...
Answer: Debut
38. All types of wrestling, boxing, fencing, characterized by contact confrontation between two opponents in a battle or duel regulated by the rules of the competition, are designated as ...
Answer: Martial arts
39. Organic substances that are part of biological membranes, forming an energy reserve, creating protective and thermal insulation covers, performing hormonal functions, participating in the mechanism of muscle contractions, are designated as ...
Answer: Fats (lipids)
40. The passage of a distance by a group of athletes selected from the total number of participants by drawing lots or according to preliminary data and starting at the same time is designated as ...
Answer: Race
In contact with
Equilibrium of a body is a state of rest of a body relative to any frame of reference, in a particular case, the immobility of a body relative to its environment. Body balance can be static or dynamic. When the body is in static equilibrium, the projection of the general center of gravity of the body is located inside the support area (Fig. 1). When walking, running, etc., dynamic balance of the body is achieved by balancing, i.e., by bringing the support area under the shifted projection of the body’s center of gravity (Fig. 2).
Rice. 1. The plane of body support during free standing: S is the point corresponding to the projection of the general center of gravity. Rice. 2. Restoring body balance by compensating changes in the activity of the leg muscles when bending the body forward. The projection of the center of gravity (vertical line) is returned to its previous position on the support plane.
A number of complex systems are involved in maintaining the body's state of balance. The vestibular apparatus plays an important role. Its receptor part is located in the inner ear and consists of the vestibular sacs and three semicircular canals. When the vestibular apparatus is excited, the sensitive hairs are irritated. The resulting impulses are transmitted along the vestibular nerve to the brain. In the process of maintaining body balance, the vestibular system interacts closely with the visual apparatus. Both of these apparatuses (vestibular and visual) have extensive bilateral connections with the cerebellum. It is also a very important innervation link in maintaining body balance. Numerous muscles, tendons, joints and skin play an important role, and above all muscle mechanisms, as well as proprioceptive reflexes. The coordination of all these mechanisms that ensure the balance of the body occurs at different levels of the nervous system - in the spinal cord, brain stem and in the cerebral cortex.
Body balance is studied using numerous methods. Among them is the method of stabilography - registration of movements of the projection of the general center of gravity over the area of support. The balance of the body is disturbed in a variety of diseases: lesions of the vestibular apparatus, cerebellum, lesions, etc.
The balance of the body is its immobility relative to the environment; in a narrow sense - maintaining a certain (for example, vertical) position.
According to the provisions of statics, the balance of the human body in a vertical stance is of an unstable type, since the overall center of gravity of the body lies above the area of support. When standing, the area of support is enclosed within the surface formed by the outer contours of both feet and the lines connecting their anterior and posterior extreme points. The balance of the body is maintained until the vertical (projection), lowered from the general center of gravity of the body, does not go beyond the support area (static balance of the body). If the projection of the general center of gravity has gone beyond the area of support, then restoring the balance of the body is possible only by balancing, i.e., bringing the area of support under the shifted projection of the general center of gravity (dynamic balance of the body). This type of body balance occurs during all types of movements - walking, running, skating, cycling, etc. When standing quietly, the vertical through the general center of gravity of the body (Fig. 1, bottom arrow) passes in front of the ankle joints (4 -5 cm) and the axis of the knee joints (by 0.5-1.5 cm) and behind the axis of the hip joints (by 1-3 cm), and the vertical through the center of gravity of the upper half of the body (Fig. 1, top arrow), located above the axis of the hip joints, passes in front of the spinal column (1-2 cm anterior to the IV lumbar vertebra). Thus, the body weight creates static (overturning) moments of forces relative to a number of joints: the action of the force of gravity of the body is aimed at extension at the hip and knee joints, flexion at the ankle joints and forward flexion of the torso, etc.
Maintaining static balance of the body is possible if the total overturning moment created by the force of gravity of the body and other external forces is counteracted by a balancing (fixing) moment of equal magnitude and opposite in direction created by internal (muscular) forces. The greater the static (overturning) moment acts on a given joint, the greater the force the muscles of this joint must develop to fix the position. As the registration of electrical activity of the muscles shows, the distribution of muscle efforts while maintaining a vertical posture corresponds to the biomechanical features of this body position, that is, it corresponds to the magnitudes and direction of the moments of gravity acting on the joints. Thus, the greatest activity is found in the muscles - extensors of the ankle joints, in which the static moment of gravity has the greatest value. Along with a decrease in static moments in the higher knee and hip joints, the degree of electrical activity of the muscles also decreases (Fig. 2).
Even with a deliberately motionless posture, constant mutual displacements of the body parts relative to each other occur (for example, due to the act of breathing and other reasons), changing the static overturning moments, which leads to the need for continuous dynamic adaptation of the corresponding balancing muscle moments. This dynamic process is reflected in body vibrations, which can be recorded directly (cephalography) or indirectly by moving the projection of the general center of gravity along the support platform (stabilography). The complex nature of the stabilogram (Fig. 3) reflects the activity of a multi-level system for regulating a person’s vertical posture, which includes various parts of the nervous system.
The main working mechanism for maintaining posture is the spinal system of the proprioceptive stretch reflex, which determines postural tone. The receptors for this reflex are muscle spindles located in the muscles, the impulse of which increases when the muscle is stretched. The impulse from the muscle spindles has a reflex stimulating effect on the motor neurons of both the intrinsic muscle and the synergist muscles. In reflex postural tone, two components can be distinguished: static, which determines the background activity of the postural muscles, and dynamic, which determines the continuous correction of the slightest violations of posture. In accordance with this, the stretch reflex system includes two types of receptors - primary (dynamic) and secondary (static) endings of muscle spindles and two types of motor neurons - fast (phasic) and slow (tonic), associated with fast and slow muscle fibers. The level of activity of the stretch reflex system and its sensitivity to changes in posture is adjusted and regulated by the higher parts of the central nervous system in accordance with the information that these parts receive from the motor, cutaneous, vestibular, and visual analyzers.
In the motor analyzer system (see Movements) to maintain body balance, in addition to afferentation from muscle receptors, afferentation from receptors of the articular-ligamentous apparatus also plays a significant role, signaling the direction and rate of change in the joint angle. Of particular importance is afferentation from the receptors of the articular-ligamentous apparatus of the cervical spine, which affects the redistribution of the reflex tone of the muscles of the limbs and torso in accordance with changes in the position of the head [cervical-tonic reflexes (see Magnus-Klein reflexes)]. A similar role is played by afferentation from the receptors of the vestibular apparatus (see), providing analysis of the position and movement of the head in space and the implementation in response to the action of adequate stimuli (acceleration, change in gravity) of tonic reflexes, including static ones, including posture reflexes from the labyrinth to limbs, neck and torso, and statokinetic as well as autonomic reactions. Disturbances in body balance, which are observed in the clinic with lesions of the cerebellum (see), are apparently associated with the importance of the latter in the coordination of proprioceptive and vestibular postural reflexes.
The participation of the visual analyzer in maintaining body balance is associated, on the one hand, with ensuring visual orientation of the body’s position in relation to surrounding objects, and on the other, with the general effect of light as one of the most important factors determining the level of central nervous system activity. In this regard, closing the eyes leads to an increase in the amplitude of body vibrations, which also increases when wearing opaque glasses or when examining in a darkened room (V.S. Gurfinkel). When the subject is in the Romberg position (see Romberg symptom) - with the feet shifted, the area of support decreases, and the arms extended forward create a large overturning moment, which places increased demands on the posture regulation system. Under these conditions, closing the eyes, causing additional vibrations of the body, can lead to a clear imbalance of the body and even a fall.
We are amazed at the exceptional ability of gymnasts to maintain balance in the most risky positions. Remember, for example, tightrope walkers on a swinging rope. Many of them perform acrobatic tricks, turning over in the air, and then returning to the rope again, while maintaining their balance.
Admiring the art of gymnasts, acrobats, tightrope walkers, and figure skating masters, we do not think about the fact that the ability to maintain a certain pose while performing any movement is not limited to athletes and circus performers. Every practically healthy person possesses it to a certain extent. If the function of the organs that ensure balance is sharply disrupted, the person cannot walk, he is forced only to lie down.
Our body is affected by various physical factors. The most important of them is the force of attraction of the Earth or gravity. Therefore, controlling balance and performing any movement are mainly subordinated to overcoming this force.
The human locomotor system has more than 200 bones. From a mechanical point of view, it is a system of various levers, the balance of which, and therefore the balance of the entire body, is possible when the sum of the moments of forces acting on it relative to the axis of rotation is equal to zero. If the equality of the moments of forces is violated, then the system of levers begins to rotate in the direction of the force whose moment is greater, and the person loses balance.
The main regulators of balance are the muscular and vestibular apparatus. However, without the participation of the senses, the balance regulation system becomes unstable. Try, for example, standing on your toes and closing your eyes, and you will feel that turning off your vision leads to instability of your balance.
Regulation of postures and movements in everyday life is carried out reflexively - automatically. As you know, all our organs and tissues have sensitive nerve endings - receptors. The main regulators of balance are muscle and vestibular receptors.
Stretching and contracting muscle fibers irritate muscle receptors. And changes in the position of the head and the entire body in space are sensitively captured by the receptors of the vestibular apparatus, located in the area of the inner ear. From the receptors, excitation is transmitted along nerve fibers to the central nervous system. Signals constantly entering the brain bring information about changes in the position of our body. The cerebral cortex processes it and immediately sends impulses in the opposite direction - to the muscles, which restore the balance of the body. Without such excitations, says I.P. Pavlov, “the movement cannot be performed, because it is not regulated at each moment. In this case, a person can say to himself that he does not feel his movements at every moment and therefore cannot control them.” A similar phenomenon can be observed, for example, in a state of weightlessness, when information from muscle receptors and the vestibular apparatus stops and a person does not feel the balance of his body. Therefore, he has to visually navigate in relation to the objects around him.
Balance is a dynamic process: in any position, the human body does not remain absolutely motionless. We seem to lose our balance for a moment and restore it again. Running, walking and other actions, even standing in one place, require constant effort to maintain body balance in the desired position. This is a familiar and invisible process for us. But as soon as we stumble while walking or running, we make so-called safety movements: we jump, thereby resisting the force of inertia, we deflect the body, as if bringing the center of gravity under the fulcrum, falling, we put our hand in, etc. In the subway, take a closer look at the people who get on and off the escalator: for greater stability, they move, figuratively speaking, with a “duck walk,” with their legs spread wide apart and with frequent movements transferring the weight of their body from one leg to the other.
Another example. To maintain balance in place when the vehicle suddenly stops, the passenger involuntarily leans in the direction opposite to the direction of movement.
Who hasn’t had to watch a person walking next to you slip and fall clumsily without even making an attempt to stand up? What would an athlete with a fairly developed sense of balance do? He will instantly determine the direction and speed of his body's deviation in order to immediately restore it, making several deft movements, and thereby avoid falling.
The higher the training, the easier a person adapts his movements and body position to changing conditions. The optimal level of development of the ability to control body balance allows us to perform various household and industrial movements most clearly and economically.
A good athlete never complains of dizziness or discomfort while riding on amusement rides, swings, or traveling in public transport. And for physically “retarded” people this is sometimes a real scourge. Often they have to refuse to travel by air or sea. This is explained by the fact that an insufficiently trained vestibular apparatus, under the influence of changing speed, jerking, rocking, comes into a state of irritation: the pulse quickens, nausea appears, dizziness - the state of health worsens. Weak vestibular stability may also be congenital. However - and this has been proven by practice - in any case, the vestibular apparatus can be trained. Of course, before you start training, you should definitely consult your doctor to see if there are any contraindications to training.
It is recommended to perform various gymnastic elements (somersaults, turns, coups) and special, so-called rotational exercises: circular movements of the head, turns in place in a circle (turning the entire body and stepping from foot to foot). You should start with 6-8 rotational exercises, and then gradually increase the number of repetitions by 1-2 movements every week. It is advisable to study for 3-4 months. It is during this period that with systematic training that the vestibular apparatus can be developed quite well.
Swinging on a swing is a good way to develop the vestibular apparatus. Therefore, do not miss the opportunity to swing, even if it is unpleasant for you. At first, swing with a small amplitude, then gradually swing more and more. The vestibular apparatus develops very well when jumping on a trampoline. As a rule, systematic training will make “seasickness” recede.
High stability of the vestibular system is inherent in gymnasts, acrobats, pilots and astronauts. This is to a large extent a consequence of regular training and systematic training on special simulators.
If you're wondering how well you can balance, try the exercises below. This will be a kind of test of your vestibular apparatus.
For someone who overcomes the entire complex, the balance function deserves an excellent rating. Those who can complete the first ten exercises or less need to develop the vestibular apparatus. If desired, these simple exercises can be included in your training complex. Start with the first two; Having mastered them, move on to the next, more complex ones. When performing exercises, try to maintain balance as long as possible.
| Heels and toes together, hands on waist, eyes closed. We stand in this position for 20-30 seconds. | |
| Feet on the same line (right in front of left or vice versa), hands on the belt; We stand in this position for 20-30 seconds. The same, but with eyes closed; stand for 15-20 seconds. |
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| Feet together, hands on the belt, rise on your toes; stand for 15-20 seconds. The same, but with eyes closed; stand for 10-15 seconds. |
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| Hands on the belt, bend your left leg, lifting it off the floor, rise on the toe of your right leg; stand for 15-20 seconds. Same with the other leg. Then we do the same, but with our eyes closed. |
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Standing on your toes (feet together), bend your torso forward 5-8 times to a horizontal position (pendulum-like movements); one tilt per second. The same, but with eyes closed. |
| Feet on the same line (right in front of the left or vice versa), hands on the belt, perform 8-10 body bends to the left and to the right (pendulum-like movements); one tilt per second. Same thing, but with eyes closed |
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| Standing on your toes (feet together), tilt your head as far back as possible; hold this position for 15-20 seconds. The same, but with your eyes closed, stand for 10-15 seconds. |
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| Standing on your toes, perform 8-10 springing movements with your head left and right; one movement per second | |
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Standing on the toe of your right foot, hands on your belt; perform 8-10 swing movements with your straight left leg back and forth (with full range of motion). Same with the other leg. |
| Standing on your toes, perform 10-12 quick tilts of your head back and forth. | |
| Rise on the toe of your right leg, bend your left leg, lifting it off the floor, tilt your head back as far as possible, close your eyes; stand for 10-15 seconds. Same with the other leg. |
Body balance - state of stable body position in space.
While standing, i.e. in a vertical position of the body, the resultant of all forces directed to the general center of gravity (GC) of the body is located at the level of the second sacral vertebra and is projected onto the central portion of the support area (sole of the feet). Any change in the vertical position caused by movement of the head, torso or limbs leads to a shift in the GCP. Preservation of R. t. in such conditions is achieved by a reflex contraction of the postural muscles, i.e. muscles that ensure maintaining posture.
With the help of specific postural reflexes, the moving mass of the body is balanced in conditions when the central gravity is transferred from one leg to the other, and movements when walking and running. Using balancing movements, as well as adjusting support forces, a person is able to maintain balance at the moment; when the center of gravity of his body goes beyond the support area, as, for example, for a runner at the moment of start. The biomechanical feature of movements during walking, running, cycling, and rope walking is that when they are performed, the supporting surface is brought under the projection of the center of gravity.
Another group of postural reflexes consists of protective movements that allow you to maintain balance when horizontal or rotational forces act on the body. Inclinations of the support area are accompanied by compensatory changes in posture, covering all muscles of the body. Normally, restoration of lost balance is achieved with the help of automated righting reflexes involved in the implementation of complex voluntary movements .
Contraction of antigravity muscles can be caused by afferent impulses,
coming from the tactile receptors of the sole of the foot, the receptors of the retina and the vestibular apparatus. In a standing position, these afferent systems have a stabilizing effect on the fluctuations of the central nervous system due to the activation of the supporting muscles along the a- and g-efferent pathways. Mechanisms for regulating the excitability threshold of proprioceptors ensure plastic adaptation of muscles to various motor acts. Visual and vestibular postural reflexes play a particularly important role in the formation of anticipatory motor commands when walking on uneven surfaces (ascent, descent). In pathological cases, optomotor postural reflexes compensate for the loss of proprioceptive afferentation; under normal conditions, vision mediates the interaction of systems of postural balance and orientation in near space.The central regulation of R. t. is assumed to be ensured by a hierarchically constructed functional system that integrates multimodal afferentation using generalized parameters, which apparently include the position of the body in space. The activity of this “tracking” system, which registers the difference between the real and the given position, determines the current and advanced regulation of the postural components of voluntary motor acts.
The afferent pathways of postural reflexes pass through the thalamus, and the efferent centers are located in the basal ganglia, when damaged (for example, with e), loss of postural reflexes occurs. The bulbar and spinal centers of extensor (including extensor) reflexes normally experience an inhibitory centrifugal influence.
Therefore, when the anatomical integrity of the pyramidal tracts is violated, spasticBalance is the ability of the body to maintain its stable position both in motion and at rest. There are two types of equilibrium - static and dynamic. Static balance determines the stability of a motionless body, for example a person standing quietly in place. A body moving at a constant linear or angular velocity has dynamic equilibrium. Since all bodies in nature are affected by gravity, it is almost impossible to find examples of dynamic equilibrium in everyday life. A practical manifestation of dynamic balance is balance in movement, for example when running or jumping.
SOURCES OF EQUILIBRIUM
The sources of balance can be considered from the point of view of two different fields of science: physiology and human biomechanics.
Physiological sources
Balance occurs when the body is in a stable position. By aligning your legs, hips, spine and head in one line, you acquire a stable vertical position. Special sense organs are responsible for maintaining body balance, helping to determine how reliable and stable the body position is.
The most important condition for maintaining balance is the presence of a visual signal. Using vision, you can instantly determine the position of your body relative to the ground. To test the importance of visual cues, try closing your eyes and standing on one leg. You will feel your body begin to sway and your arms instinctively spread to the sides.
Tactile signals also serve to maintain balance. The balls of the feet contain an extensive network of sensitive sensors. Reacting to changes in the pressure of the ground beneath them, they send appropriate information about this to the brain, which makes it possible to quickly change body position to maintain balance. To test the operation of these sensors, stand with one foot on a soft surface, such as a mattress or thick gymnastics mat. As soon as the surface you're standing on bends under your weight, your body will immediately change position slightly, responding to signals coming from the balls of your feet.
Finally, an important organ that controls balance is the vestibular apparatus, located in the inner ear. It consists of two types of receptors: semicircular canals, which are responsible for angular movements, and so-called otoliths, which regulate linear movements. The vestibular apparatus controls the position of the head in space (vertical or inverted) and sudden changes in the direction of movement. Its main function is to maintain balance.
Thanks to the high sensitivity of the vestibular apparatus, the central nervous system has the ability to correct the position of the body in space, sometimes even to the point of loss of balance. The vestibular apparatus, in addition, controls the “restoration reflex,” which is used in cases of disorientation above all other sensory and motor systems.
The recovery reflex is responsible for the vertical position of the body. Receiving signals from the visual and tactile senses, as well as from the vestibular apparatus, the body constantly strives to maintain a stable position relative to the force of gravity acting on it. If you lose your balance or become disoriented in space, the righting reflex immediately begins to return the body to an upright position, first stabilizing the position of the head, then the shen, then the upper and finally the lower body.
Biomechanical sources
The human body has a complex physiological safety system in case of loss of balance. All her activities are aimed at maintaining a stable and stable body position. However, it is constantly opposed by such a physical phenomenon as gravity. And in this case, the task of maintaining balance is assigned to biomechanical factors.
Every martial arts athlete has sooner or later encountered the term?gravity? in relation to one movement or another. ?Lower center of gravity? ? the most common adjustment to athletes’ actions when studying stances and movements. But how many people know where this gravity is located and how it can be lowered?
The true center of gravity is located at the intersection of gravitational lines for vertical and horizontal orientation of the body. Imagine that your body is divided vertically into two perfectly equal parts and horizontally into two parts of equal weight. The center of gravity will be located at the intersection of these vertical and horizontal dividing lines.
The center of gravity defines the point at which the orientation of a body relative to the ground is independent of its weight. Simply put, this is the point at which you would maintain stable balance if it were possible to use it as a support for your body.
However, the most interesting property of the center of gravity is that it constantly moves relative to the body as parts of the body change their position in space. Your center of gravity is at completely different points when you stand, sit, or bend over. Moreover, at certain moments the center of gravity may even be outside the body.
Imagine a hollow object, such as a cap or helmet. The centers of gravity of these objects will be outside their material shell, located at a certain point in space inside the cavity. This phenomenon is also characteristic of the human body. In certain cases, when the strong flexion or stretching of the hips or torso required during certain gymnastic exercises, the athlete's center of gravity is at a point in space surrounded by his body.
Knowledge of the location of the center of gravity is extremely important for maintaining balance in motion and at rest. The stability of the body position depends on the location of the intersection point of the vertical and horizontal lines, which determines the center of gravity.
