Under fatment, the special physiological state of the body, arising after the work done and expressing in a temporary decrease in working capacity, is understood.

Performance is the value of the functionality of the human body characterized by the number and quality of work performed during a certain time. During labor activity The performance of the body varies in time. There are three main phases of self-replacing person states in the process of employment:

• - therapy phase, or increasing performance; During this period, the level of performance is gradually increasing compared to the initial; Depending on the nature of the labor and individual characteristics of the person, this period lasts from a few minutes to 1.5 hours, and with a mental creative work - up to 2 ... 2.5 hours;
• - phase of high resistance of health; It is characterized by a combination of high labor indicators with relative stability or even a certain reduction in tension physiological functions; The duration of this phase can be 2 ... 2.5 hours or more depending on the severity and tensions of labor;
• - phase of reduced performance, characterized by a decrease in the functionality of the main human working bodies and accompanied by a sense of fatigue.

One of the objective signs is a decrease in labor productivity, it is generally subjective expressed in the feeling of fatigue. In reluctance or even the impossibility of further continuation of work. Fatigue can occur with any form of activity.

Target is associated with changes in the physiological condition of the whole organism as a result of long or hard work, and a variation occurs in the central nervous system.

With prolonged exposure to the body harmful factors The production environment can develop overwork, sometimes called chronic fatter, when a night rest does not completely restore the working capacity dropping during the day.

The basis for the occurrence of overwork is the constant inconsistency of the duration and severity of the work and time of rest. In addition, unsatisfactory labor situation, unfavorable living conditions, poor nutrition can contribute to the development of overwork.

Symptoms of overwork - various violations by the neuropsychic sphere, for example, weakening attention and memory. Along with this, the overwater people are often observed with headaches, sleep disorders (insomnia) worsening appetite and increased irritability.

In addition, chronic overwork usually causes a weakening of the body, reducing its resistance to external influences, which is expressed in increasing the incidence and injury. Quite often, this condition predisposes to the development of neurasthenia and hysteria.

Prevention of fatigue. Treatment prevention activities:

Physiological rationalization of the employment process on saving and restricting movements during operation;

Uniform load distribution between different muscle groups;

Compliance of production movements with the usual movements of man;

Rationalization of working postures;

Exemption from unnecessary utility operations.

Automation and mechanization of production, eliminating the need for excessive muscular efforts when working and staying working in adverse conditions

An important measure of prevention is the rationale and introduction into the production activities of the most appropriate mode of labor and recreation, i.e. The rational system of alternation periods of work and interruptions between them.

Of great importance in the prevention of fatigue has an active leisure (phenomenon, open I.M. Sechenov), in particular, exercise, since tired muscles restore their performance not at all over peace, but when working other muscular groups.

It effectively use functional music, as well as relaxation rooms or the psychological unloading room.

The necessary factor for the prevention of fatigue is undoubtedly sanitary landscaping of industrial premises (cubature, microclimatic conditions, ventilation, illumination, aesthetic design).

Man as an element of a "man-environment" system.

For millions of years, in the course of evolutionary and social development, a person has developed a natural system of protection against dangers. This system is characterized by perfection, but has certain limits.

A person directly communicates with the environment with its analyzers, which are sometimes called feeling devices. Characteristics of man analyzers must be considered when creating safe systems. Any analyzer consists of a receptor conductive nerve paths and a brainstone. The receptor turns the energy of the stimulus into the nervous process. Conducting paths transmit nerve impulses to the cerebral bark; The brain end of the analyzer consists of a core and scattered from the core of the elements. Scattered elements provide nervous connections between different analyzers. There is a bilateral connection between the receptors and the brain end, which ensures the analyzer self-regulation. A feature of human analyzers is the pavement of analyzers, ensures high reliability of their work due to partial duplication of signals and dynamic ambiguous functional asymmetry.

The main characteristic of the analyzer is sensitivity. Not every irritant affecting the analyzer causes a feeling. So that it occurs, the intensity of the stimulus should reach some specific value. With an increase in the intensity of the irritant, the moment occurs when the analyzer ceases to work adequately. Any impact exceeding the intensity of a certain limit causes pain and violates the activity of the analyzer. The interval from the minimum to the maximum adequately sensible value determines the sensitivity range of the analyzer. The minimum value is made called the lower absolute threshold of sensitivity, and the maximum-top. Absolute sensitivity thresholds are measured in absolute irritability values. In the event that no interference is the outer stimuli, they talk about a differential or difference threshold. The minimum difference between the intensities of two stimuli, which causes a barely noticeable difference in sensations, is called a differential threshold, or a difference threshold. The psychophysical experiments found that the magnitude of sensations varies more slowly than the power of the stimulus. The main psychophysical law of Weber-Ferechner, having an approximate value, is expressed by the formula

The main factor causing fatigue is the physical or mental load falling on the afferent systems during operation. The dependence between the magnitude of the load and the degree of fatigue almost always happens linear, that is, the more load, the more pronounced and early is fatigue. In addition to the absolute magnitude of the load, a number of its features are also affected on the nature of the development of fatigue, among which it is necessary to allocate: a static or dynamic nature of load, permanent or periodic nature and load intensity.

Along with the main factor (workload), leading to fatigue, there are a number of additional or contributing factors. These factors themselves do not lead to the development of fatigue, however, combined with the action of the main, contribute to the earlier and pronounced onset of fatigue. Additional factors include:

External environment factors (temperature, humidity, gas composition, barometric pressure, etc.);

Factors associated with violation of labor and recreation modes;

Factors caused by changing the usual daily biorhythms, and turning off sensory irritations;

Social factors, motivation, relationship in the team, etc.

The subjective and objective signs of fatigue are very diverse, and their severity largely depends on the nature of the exercises performed and the psycho-physiological characteristics of a person. Subjective signs of fatigue include a sense of fatigue, general or local. At the same time, pain and feeling of numbness in the limbs, lower back, muscles of the back and neck, the desire to stop working or change its rhythm and others.

Objective signs are even more diverse. In any kind of fatigue, a detailed examination may be detected in the nature of the functioning of any body system, ranging from the motor, cardiovascular and central nervous system and ending with such, which seemed not related to the direct work of systems as digestive and separation. Such a variety of changes reflects the patterns of the functioning of the organism as a whole and characterizes the direct reactions to ensure the functional load, as well as adaptation and compensation shifts.

When the central nervous system is tested from the central nervous system in the cerebral cortex, the weakening of conditionally reflex reactions, the unevenness of tendon reflexes, and during the overwork - the development of neurosis-like states.

Changes in the cardiovascular system are characterized by tachycardia, lability arterial pressure, inadequate reactions to the dosage physical activity, some electrocardiographic shifts. In addition, saturation is reduced arterial blood Oxygen, breathing is rapid and the pulmonary ventilation deteriorates, which can significantly decrease during overwork.

The amount of erythrocytes and hemoglobin decreases in the blood, leukocytosis is observed, the phagocytic activity of leukocytes is somewhat oppressed and the number of platelets is reduced. When overwork, sometimes there are pain and increase in liver, violation of protein and carbohydrate metabolism.

However, all these changes do not arise simultaneously and do not develop in the same direction. Their dynamics are determined by a number of patterns, and only finding these patterns, you can not only understand the development of fatigue, but also give the correct assessment of the condition of a person and actively oppose the developing fatigue.

Changes arise primarily in those organs and systems that directly carry out sports activities. In physical work is muscular system and motor analyzer. At the same time, changes may appear in those systems and organs that ensure the functioning of these main working systems - respiratory, cardiovascular, blood, etc. On the other hand, it may also be such a position when a decrease in the functions of the body (basic and providing systems ), and sports efficiency is still preserved at a high level. It depends on the moral and volitional qualities of the athlete, motivation, etc.

Changes in some systems that are not directly related to ensuring special exercisesAt fatigue, they have a fundamentally different genesis and are either secondary, having a common, non-specific nature, or have regulatory or compensatory significance, that is, aimed at balance functional state organism. It becomes obvious from the above, that the leading importance in the development of fatigue phenomena has the central nervous system, ensuring the integration of all organism systems, regulation and adaptation of these systems during operation. The resulting change in the functional state of the central nervous system in the process of fatigue reflects, thus, the dual process is the changes associated with the restructuring of the functioning of the adjustable systems, and the shifts arising in connection with the process of fatigue in the nerve structures themselves.

Target is dynamically in its essence and in its development has several consistently emerging signs. The first sign of the occurrence of fatigue in physical work is a violation of the automation of working movements. The second feature that can most clearly be installed is a violation of coordination of movements. The third sign is a significant voltage of vegetative functions while improving the productivity of the work, and then the violation of the most vegetative component. With pronounced degrees of fatigue, new little learned motor skills can fade completely. At the same time, the old, stronger skills that do not correspond to the new setting are very often distinguished. In sports practice, this can cause various disruptions, injuries, etc.

Signs of fatigue during static work, for example, you can reveal by spending a simple laboratory work. It is necessary to take the cargo in the hand (3-4 kg) and pull it towards strictly horizontally, pre-marking the level on which there is a hand on the wall. Turning on the stopwatch to determine the time and phase of fatigue using the table (see applications Table No. 7).

Causes of fatigue and factors contributing to its development

The main cause of fatigue in the muscles may be the accumulation of a large number of non-oxidized lactic acid. This makes it difficult for the further disintegration of power substances and reduces muscle performance.

It may be associated with changes in the function of the internal secretion glands (for example, a change in the ratio between the work of the glands, partial exhaustion of some glands and others).

Fatigue may occur due to the insufficient performance of the cardiovascular and respiratory system. Due to the lack of oxygen and excess carbon dioxide, the acidity of blood changes, the sugar level falls in it.

But the leading role in the development of fatigue is played by the central nervous system. Nervous cells are very sensitive to changes in the composition of the washing of its tissue liquids. Skeletal muscles can still retain their performance, and in nerve cells it is already decreasing, lability falls, the excitability of nerve cells decreases, the normal process of the ratio of excitation and braking processes is disturbed, proceedings are developing.

Fatigue is a set of changes in the physical, mental state of a person developing as a result of activities and leading to a temporary decrease in performance efficiency.

Fatigue is a process that occurs in the course of operation and limiting its duration. It is typical for all phases of health, starting with subcompensation, when there is a significant decrease in physiological reserves, and the body moves to energy-less favorable reactions, for example, maintaining minute blood flow due to an increase in the frequency of heart cuts instead of a more advantageous reaction of increasing shock volume. Or, for example, the implementation of motor reactions is carried out by a large number of functional muscle units when weakening the strength of cuts of individual muscle fibers, i.e., violation of the alternation of periods of work and leisure of muscle groups involved in reducing. In humans in initial stages The fatigue decreases the efficiency of performance, i.e. the magnitude of the physiological and psychological costs needed for the same labor act, actions, and then the productivity of labor and the effectiveness of activities are also falling.

Under fatigue, first of all, the stability of vegetative functions, the strength and speed of muscular abbreviation is disturbed, the regulation of functions, development and braking of conditional reflexes deteriorate. As a result, as mentioned above, there is a slowdown in the rate of activity, the rhythm, accuracy and coordination of movements are disturbed and it turns out that large energy costs are required for the same activity. The thresholds of sensory (sensitive) systems increase, in the decision-making processes, the finished stereotypical solutions are dominated during mental activity, the person's attention is weakened and switches with difficulty. For fatigue, an increase in the number of errors and the change in their structure is characterized, so in the initial phases of fatigue, quantitative errors are dominated, and the subsequent phases - high-quality appear.

The development of the pattern of fatigue can generally be characterized as a violation of an adequate (correct) response of the body with the requirements of the nature of activity. At the same time, all 3 basic adequacy requirements are violated:

Optimality of private reactions underlying the basis of activities;

And their coordination with each other;

Qualitative and quantitative compliance of the body's response to the requirements of the problem and minimizing the consumption of physiological reserves.

With pronounced fatigue, complete termination of work is observed.

Troying in humans, like an animal, is associated with a number of mechanisms associated with biochemical changes at the cellular level and a violation of conditional reflex activity. But the dynamics and a number of structural mechanisms of fatigue in humans are also regulated by the motives of its goals, character. Therefore, fatigue in the animal and in humans has a number of fundamental differences. In particular, animals do not have the strict development of fatigue phases, more characteristic simply consistent quantitative indicators and less expressed change in the structure of activity. They have virtually not suppressed by a volitional effort.

On the dynamics of fatigue affects the nature of the activity, primarily its intensity and pace. There is an optimal intensity of activity in which fatigue comes later. An increase or decrease in this intensity accelerates the onset of fatigue.

For example, everyone is well known that fatigue is most rapidly developing with monotonous, static work and sensory (sensual) depleted activities. If a person performs the same operation for a long time, physical exercise, requiring a limited set of movements, its attention is reduced quickly, the positive motives of activity are fired. This usually occurs with highly specialized work on the conveyor, when assembling any mechanisms, the manufacture of parts (monotonous operation).

Quickly tired man performing work in a static pose (knitting, embroidery, printing, work at a computer, etc.).

The external stimuli coming to man, such as sound and light signals, which contain information about activities are influenced by fatigue. For example, the driver has done a way to 500 km in a light day and under good weather conditions, it feels fatigue. But the same driver who passed the same way with bad weather conditions (fog, night, heavy rain) will definitely get tired even more. High level Noise tires a person, but complete silence can cause irritation and fatigue in humans. Therefore, in production should be given a lot of attention to the microclimate of the working medium: air temperature, its humidity, composition, the presence of chemical impurities, noise, vibration, illumination, etc.

The rate of occurrence and development of fatigue depends on a number of psychological characteristics of the individual - the level of anxiety, volitional qualities, including perseverance and other activation parameters, i.e., such functional properties of a person who ensure the degree of implementation in the specific activity of its potential opportunities. For example, attention, as an activation parameter provides great ability to memorize. A high level of soliving qualities of the individual allows you to maintain a high level of activity even with a pronounced feeling of fatigue.

The development of fatigue depends on the state of human health and its physical training, which not only cause large physiological reserves, but also contribute to a faster and sustainable mobilization and formation of functional systems. For example, physically strong and healthy, if necessary, can go a day 5-10 km and it will feel great, although before that he has not experienced such a long time physical Loads. You may simply be a sick person, or it will be extremely tired, but may also be inoperable for a long time. Or another example, the driver with experience, does not feel fatigue, although he spent on the way for many hours in a row, and the driver of a newcomer who had a trip from one settlement to another (even if it was only a few tens of kilometers), could feel very tired.

Answer number 8 and 31

Exterior signs fatigue

Fatigue is physiological characteristics human organism, representing a temporary decrease in the body's abilities to full-fledged activities. Externally, the main symptom of fatigue is a deterioration in the quality of work and reduce its tempo. Still external signs of fatigue is:

· Changes the shade of skin. Depending on the intensity of work, it can range from a slightly pinkish to the Punchovo - red (with pronounced cyanosis -plupping sinusiness).

· Strengthening sweat glands. With light intensity, these are minor sweat droplets, localized mainly on the face in the frontal part. With severe physical work, the selection of sweat is quite abundant. At the same time, on the clothes, it is possible to observe stains from salt, which goes together with then.

· Change of respiratory rhythm. It may vary from exactly - rapid to more rhythmic and intensively participated. Add lifting and lowering shoulders in breathing tact.

· Failures in coordination of movement. If at the beginning of the work of the person's movement, less energy is coordinated and on their execution, then in the subsequent movement becomes more mismatched, swaying, tremor appears in the upper and / or lower limbs, there is no strength, nor the desire for further movement.

If a person begins to feel fatigue or there are external signs of fatigue from a number of employees, it is worth suspending activities and take a little break, giving the body to at least partially recover.

Signs of fatigue and overwork

What is fatigue and overwork? Fatigue - this physiological response of the body on the load applied to it. Overwork is a long sense of fatigue, arising against the background of the lack of a long holiday time. So what are the signs of fatigue and overwork and what is the difference between these two terms?

Fatigue is on the physical, psychological and emotional level the depletion of the human body. Whereas overwork is a long sense of feeling of exhaustion, that is, fatigue. The state of overwork is for many modern people with a constant feeling, due to our rhythm of life and constant in stressful state. To a greater extent, this fact concerns residents of megacities. This situation is dangerous to human health, and in some cases, maybe not directly, and for his life.

Signs of fatigue and overwork are quite obvious and familiar to almost everyone.

· Such a person has constant drowsiness.

· It can be understood permanent practically non-stop headaches, the intensity of which is changing throughout the day.

· Even after, it would seem, a calm night, such a face feels weak and "broken." That is, during sleep, the body is no longer able to restore the volume of energy that was spent throughout the day.

· Despite the constant desire to sleep, it is not long for a long time.

· Pursuing such a person and other diseases. It would seem that only trembled one thing as the other is immediately clinging. What is the result of reduced immunity.

· The sign of fatigue and overwork is the deterioration of memory and reduce performance at the physical level.

· The person appears apathy and the desire to keep it alone alone.

· The scattered attention appears. To this person, it is necessary to make certain efforts to focus.

· All these factors can cause an increase in blood pressure.

· In such a state, people become inept.

If a person is subjected to unfavorable factors for a long time, fatigue goes into the chronic stage. It is chronic fatigue and refer to overwork. Against the background of it falls the body's ability to resist external influences, which leads to an increase in the risk of injury or get sick.

The overwork and for the nervous system does not pass.

· Nervous breakdowns.

· Sharp mood change.

· This person has a desire to be alone.

· He may react inadequately, it would seem like a minor replica.

· Hysteria.

· Alarm feeling, increased irritability.

· Relationship voltage with loved ones.

At the same time, the signs of physical fatigue can still be attributed:

· Frequency of heart rate.

· Increased sweating.

· Poor mood or lack of any emotions (apathy) - there are simply no strength on them.

· Frequent cases when a person begins to sense a constant, different intensity, headache.

· The overwork may affect the appetite: the tired person decreases or completely disappears the desire to eat. Consequently, the body gets less energy - it turns out a vicious circle.

· Ply chronic fatigue You can observe the intestinal disorder.

· Overwork can work and, on the contrary, the hyperactivity of the body. Such a situation leads to an even greater exacerbation of the situation, since the body, contrary to logic, begins to spend more energy, the launching mechanism of self-destruction. And if to relax, man begins to use alcoholic beveragesThe situation is aggravated, and the health condition is only worsening.

Signs of the fatigue of children begin to manifest themselves:

· Weakening of differentiation in movements.

· Reducing attention and accuracy of manipulation.

· Motor concern appears.

Exterior signs various degrees fatigue share:

· Easy level of fatigue:

o Skin cover slightly pink.

o Pot droplets are highlighted in a small amount. Localizes mainly on the face in the forehead.

o The rhythm of breathing is a bit rapid, but even, without breakdowns. The person is able to breathe both through the mouth and through the nose.

· Medium level of fatigue:

o Skin cover acquires a red shade.

o Abundant sweating, which is well visible in the area of \u200b\u200bthe head and body.

o The intensity of respiratory activity increases, a person is able to breathe only through purph cavityThe volumes of nasal respiration are not enough.

o Coordination and motility remains within the normal range.

· High leveling level - overwork:

o Skin cover is quite sharply pale, in the triangle - the corners of the upper lip and nose - there is a clearly differentiable syushnosis, which has its own term in medicine - cyanosis.

o Abundant sweating, which is well visible in the area of \u200b\u200bthe head and body. On the clothes are awesome, leaving then, salts that manifest themselves in the form of bellic spots.

o The intensity of respiratory activity increases. Inhale and exhale duplicate shoulders.

o There is a mismatch of movement coordination. The person starts to be shortened as the top and lower limbsThe torso slightly shakes, problems with movement may occur.

To support your body and do not bring it to complete exhaustion, you should adjust the mode, adopting some preventive measures:

· Select time for walking in the fresh air before bedtime.

· Revise your work schedule. In it, the load time should be alternate with relaxing breaks.

· Avoid stressful situations.

· Sleep at least eight hours a day.

· It is worth removing bad habits from your life.

· The person's nutrition should be rational and rich in trace elements and vitamins. Avitaminosis is one of the main reasons for the weakening of the body and its overwork.

· You should learn how to switch attention or alternate physical work with mental, and vice versa.