Fatigue is a physiological state of the body that occurs as a result of activity and is manifested by a temporary decrease in performance. Often, the term “fatigue” is used as a synonym for fatigue, although these are not equivalent concepts: fatigue is a subjective experience, a feeling usually reflecting fatigue, although sometimes a feeling of fatigue can occur without a previous load, i.e. without real fatigue. Fatigue can appear both during mental and physical work. Mental fatigue is characterized by a decrease in the productivity of intellectual work, a weakening of attention, speed of thinking, etc. Physical fatigue is manifested by a violation of muscle functions: a decrease in strength, speed of contractions, accuracy, consistency and rhythm of movements. Efficiency can be reduced not only as a result of the work done, but also due to illness or unusual working conditions (intense noise, etc.).

The timing of the onset of fatigue depends on the characteristics of labor: it occurs much sooner when performing work, accompanied by a monotonous posture, tension of limited muscles; less tiring rhythmic movements. An important role in the appearance of fatigue is also played by the attitude of a person to the work performed. It is well known that many people during the period of emotional volume for a long time do not show signs of fatigue and feelings of fatigue. Insufficient rest time or excessive workload for a long time often leads to overwork. With overwork, headache, absent-mindedness, decreased memory, attention, and sleep are disturbed.

Overwork is a pathological condition that develops in a person due to chronic physical or psychological overstrain, the clinical picture of which is determined by functional disorders in the central nervous system. The basis of the disease is an overstrain of excitatory or inhibitory processes, a violation of their ratio in the cerebral cortex. This allows us to consider the pathogenesis of overwork similar to the pathogenesis of neuroses. Prevention of overwork is based on the elimination of its causes. Therefore, intensive loads should be used only with sufficient preliminary preparation. In a state of increased stress, intensive classes should be alternated with physical activity, especially on the days after exams or tests. Under the action of a strong stimulus (stressor), an adaptation syndrome, or stress, develops in the body, during which the activity of the anterior pituitary gland and adrenal cortex increases. These changes in the endocrine system largely determine the development of adaptive reactions in the body to intense physical or psychological activity. However, chronic overstrain can lead to depletion of the adrenal cortex and thus to a violation in the body of previously developed adaptive reactions. It should be emphasized that in the process of overfatigue development, the central nervous system turns on and regulates stress reactions. At the heart of the pathogenesis of overfatigue is a violation of the processes of cortical neurodynamics, similar to how it occurs in neuroses. In a state of overwork, a person's basal metabolism increases and carbohydrate metabolism is often disturbed. Violation of carbohydrate metabolism is manifested in the deterioration of absorption and utilization of glucose. The amount of sugar in the blood at rest decreases. The course of oxidative processes in the body is also disturbed. This may be indicated by a sharp decrease in the content of ascorbic acid in the tissues.

There are two types of fatigue: one occurs during mental activity, the other - during muscular work. However, today, when there is a convergence of mental and physical labor in production, it has become almost difficult to isolate mental or muscular fatigue in its pure form. In any work activity, there are components inherent in both mental and physical labor.

Prevention of fatigue, fatigue and overwork is based on the elimination of its causes. Therefore, intensive loads should be used only with sufficient preliminary preparation. In a state of increased stress, intensive classes should be alternated with physical activity, especially on the days after exams or tests. All violations of the mode of life, work, rest, sleep and nutrition, as well as physical and mental trauma, intoxication of the body from foci of chronic infection should be eliminated. Reinforced training after any illness or in a state of convalescence after past illnesses should be prohibited.

When performing certain physical exercises in the process of work, three main results are achieved: acceleration of the process of working out; increasing the efficiency of short-term rest in the process of work; maintaining the health of workers. Prevention of overwork is based on the elimination of its causes. Therefore, intensive loads should be used only with sufficient preliminary preparation. In a state of increased stress, intensive classes should be alternated with physical activity, especially on the days after exams or tests. All violations of the mode of life, work, rest, sleep and nutrition, as well as physical and mental trauma, intoxication of the body from foci of chronic infection should be eliminated. Reinforced training after any illness or in a state of convalescence after past illnesses should be prohibited.

The problem of restoring the normal functioning of the body and its performance after the work done (the fight against fatigue and the fastest elimination of its consequences) "is of great importance in sports. The fact is that, as the level of preparedness increases, the athlete needs an increasing strength of the stimulus (great physical activity) for ensuring continuous functional improvement of the body and achieving a new, higher level of its activity.Increased load provides structural and functional improvement of blood circulation and strengthening of the trophic functions of the nervous system, the creation of a sufficient supply of energy, an increase in the capillarization of skeletal and cardiac muscles.All this leads to an increase in the body's potential, increase in its functional reserve, adequate adaptation to physical loads, acceleration of recovery.The faster the recovery, the more opportunities the body has to perform subsequent work, and, therefore, the higher its functionality and performance. From this it is clear that recovery is an integral part of the training process, no less important than the direct training effects on the athlete.

The inevitable consequence of muscular activity is one degree or another of fatigue. Fatigue is a physiological, safety mechanism that protects the body from overstrain, and, at the same time, as a trace phenomenon of the work done, contributing to the development of adaptation, stimulates a further increase in the efficiency and fitness of the body. There is no training without fatigue. It is only important that the degree of fatigue corresponds to the work done. The degree of fatigue, as well as the speed of recovery, is due to the complex interaction of many factors, among which the main ones are: the nature of the work done, its focus, volume and intensity, health status, level of preparedness, age and individual characteristics of the trainee, the previous regimen, the level of technical training, the ability to relax, etc. If these are competitions, then the degree of their tension and responsibility, the balance of forces, and the tactical plan for holding them play a significant role. The selective effect of various training loads and work modes on the motor apparatus and its vegetative support during fatigue and recovery has been experimentally proven.

The cumulation of fatigue under certain training regimes also has a significant effect on the course of recovery processes. The duration of recovery varies from several minutes to many hours and days, depending on the severity of these factors. The faster the recovery, the better the body's adaptation to the next load, the more work it can do with higher efficiency, and, therefore, the more its functional capabilities grow and the higher the training efficiency.

With repeated large physical stresses in the body, two opposite states can develop: a) an increase in fitness and an increase in working capacity, if the recovery processes provide replenishment and accumulation of energy resources; b) chronic exhaustion and overwork, if recovery does not systematically occur.

The above provision, of course, does not mean that the training of qualified athletes should always be carried out against the background of complete recovery or super-recovery. Over the past decade, sports practice has convincingly proved not only the possibility, but also the expediency of training at the level of under-recovery during certain periods of micro- and macrocycles, which serves as an incentive to further increase the level of body activity and its performance. At the same time, medical studies showed the absence (of course, subject to all necessary conditions) of any adverse changes in the athlete's body. However, at certain stages of training, against the background of underrecovery, compensation is periodically needed to ensure a lasting recovery.

Consequently, the acceleration of recovery is a directed action on the recovery processes, one of the most effective levers for managing the training process. Acceleration of recovery can be achieved both naturally (recovery processes are trainable and it is not by chance that the speed of recovery is one of the diagnostic criteria for fitness), and by direct influence on the course of recovery processes in order to stimulate them.

The use of aids can give the appropriate effect only in combination with the natural way of accelerating recovery, due to the increase in fitness. Otherwise, shifts in recovery over time will not be adequately provided with the resources of the body, which can not only slow down the natural acceleration of recovery, but also adversely affect the functional reserve of the body. Management of recovery processes is important not only for qualified athletes who train with heavy loads, but also for all other contingents involved in physical culture and mass sports, since it contributes to the most favorable perception of loads by the body, and thus the healing effect of training. To date, a considerable arsenal of restorative means has been developed and put into practice, which can be classified according to various criteria: according to the direction and mechanism of action, time of use, conditions of use, etc. The most widespread division of restorative means into three large groups is pedagogical, psychological and biomedical, the complex use of which, depending on the direction of the training process, tasks and stage of preparation, age, condition and level of preparedness of the trainee, the previous regimen, constitutes the recovery system.

Pedagogical tools ensure the effectiveness of recovery due to the appropriate construction of training and regimen. This group of funds should be considered as the main one, because no matter what special means are used to speed up recovery, they will have the proper effect only with the right training and regimen. Pedagogical means include: a rational combination of general and special training means, the correct combination of load and rest in micro-, macro- and long-term training cycles, the introduction of special recovery cycles and preventive unloading, varying loads, training conditions, rest intervals between classes and exercises, widespread use of switching from one type of exercise to another, from one mode, work to another, a full-fledged warm-up, the use of muscle relaxation exercises, breathing exercises, self-massage techniques, etc., a full-fledged final part of the lesson, as well as a large individualization of training, rational mode (especially pre- and post-competitive period), sufficient emotionality of classes, etc.

Psychological means are aimed at the fastest normalization of the neuropsychic status of an athlete after intense training and especially competitions, which creates the necessary background for restoring the functions of physiological systems and performance. This can be attributed as psycho-pedagogical means (such as, for example, optimal moral climate, positive emotions, comfortable living conditions and training, interesting varied recreation, sparing the athlete's psyche, especially in the pre-competitive period and immediately after the competition, when recruiting teams, resettling athletes at training camps etc., individual approach), as well as psychohygienic means of regulation and self-regulation of mental states: sleep lengthening, suggested sono-rest, psychoregulatory, autogenic training, color and musical influences, special methods of muscle relaxation, control of voluntary muscle tone, the use of certain medications to balance nervous processes, etc.

The main medical and biological means of recovery are rational nutrition (including the use of its additional factors and vitamins), physical factors (hydro-, balneo-, electro-, light and heat procedures, massage, air ionization), some natural herbal and pharmacological agents, rational daily mode, climatic factors. The mechanism of action of these funds can be imagined as a combination of non-specific (the effect on the protective and adaptive forces of the body) and specific influences directly aimed at the fastest elimination of manifestations of general and local fatigue caused by the work done. Through neurohumoral mechanisms of regulation, these drugs affect the metabolism, temperature and blood supply of tissues changed due to physical activity, contribute to the replenishment of spent energy and plastic resources, the fastest removal of decay products from the body, restore the normal ratio of nervous processes, thereby contributing to the restoration of the functions of regulatory mechanisms and effector organs. , eliminate the feeling of fatigue. This allows you to accelerate the natural course of recovery processes, increase the body's adaptation to subsequent muscle activity and its performance.

The use of auxiliary means for managing physiological processes changed under the influence of the work done, in order to accelerate its recovery and prevent overstrain during subsequent loads, is physiologically justified and has nothing to do with artificial stimulation of the body to increase its performance. The use of restorative agents should be of a systemic nature, providing for the complex use of agents of various actions in close connection with a specific training regimen and methodology, that is, a rational combination of individual agents in accordance with the sport, tasks and period of training, the nature of work, the degree of fatigue, the condition of the athlete.

Recovery processes are characterized by unevenness, phasing (the phase of reduced, initial and increased working capacity, the latter is recorded not after each work, but at longer stages of training), heterochronism. Heterochronism in the restoration of the vegetative and motor spheres of the body, as well as individual vegetative links, is most pronounced in the late recovery period after exercise, as well as in less trained individuals. Therefore, when choosing restorative means, one should provide for the possibility of simultaneously influencing various functional levels of the body, ensuring its performance of the mental and somatic spheres, the motor apparatus, the central nervous and autonomic systems, in order to simultaneously remove both the nervous and physical components of fatigue.

ANSWER #8 and 31

External signs of fatigue

Fatigue is a physiological characteristic of the human body, which is a temporary decrease in the body's ability to fully function. Outwardly, the main symptom of fatigue is a deterioration in the quality of work and a decrease in its pace. Other external signs of fatigue are:

Changes in the tone of the skin. Depending on the intensity of work, it can range from slightly pinkish to crimson-red (with pronounced cyanosis - a visible cyanosis).

Strengthening the work of the sweat glands. With light intensity, these are insignificant droplets of sweat, localized mainly on the face in the frontal part. During heavy physical work, sweating is quite plentiful. At the same time, stains from salt that comes out with sweat can be observed on clothes.

Change in respiratory rhythm. It can vary from evenly - speeded up to more rhythmic and intensely - speeded up. Raising and lowering the shoulders to the beat of breathing is added.

Failures in the coordination of movement. If at the beginning of the work the movements of a person are coordinated and less energy is involved in their implementation, then in the subsequent movements they become more mismatched, swaying, tremors appear in the upper and / or lower limbs, there is neither strength nor desire for further movement.

If a person begins to feel tired or there are external signs of fatigue in a nearby person, it is worth suspending activity and taking a short break, allowing the body to at least partially recover.

Signs of fatigue and fatigue

What is fatigue and overwork? Fatigue is the physiological reaction of the body to the load applied to it. Overwork is a prolonged feeling of fatigue that occurs against the background of a lack of a long time of rest. So what are the signs of fatigue and overwork, and what is the difference between these two terms?

Fatigue is the exhaustion of the human body at the physical, psychological and emotional level. Whereas overwork is a prolonged feeling of a feeling of exhaustion, that is, fatigue. The state of overwork is a constant feeling for many modern people, due to our rhythm of life and constant being in a stressful state. To a greater extent, this fact concerns residents of megacities. This situation is dangerous for 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 is haunted by constant drowsiness.

He can be plagued by constant, almost incessant headaches, the intensity of which varies throughout the day.

Even after a seemingly calm night, such a person feels weak and “broken”. That is, during sleep, the body is no longer able to restore the amount of energy that was spent throughout the day.

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

· Such a person is pursued by other diseases. It would seem that he has only treated one thing, as another immediately clings. What is the result of reduced immunity.

· A sign of fatigue and overwork is the deterioration of memory and reduced performance at the physical level.

A person develops apathy and a desire to be left alone.

· Distracted attention appears. Such a person may need to make some effort to concentrate.

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

In this state, people become taciturn.

If a person is exposed to adverse factors for a long time, fatigue becomes chronic. It is chronic fatigue that is called overwork. Against the background of it, the body's ability to resist external influences decreases, which leads to an increased risk of injury or illness.

Overwork does not pass without a trace for the nervous system.

Nervous breakdowns.

· Sudden mood swings.

This person wants to be alone.

He may respond inappropriately to seemingly insignificant remarks.

· Hysteria.

Feeling of anxiety, increased irritability.

Tension in relationships with loved ones.

At the same time, signs of physical fatigue can also include:

· Increased heart rate.

· Increased sweating.

Bad mood or lack of any emotions (apathy) - they simply do not have the strength.

· There are frequent cases when a person begins to feel a constant, varying intensity, headache.

Overwork can also affect appetite: a tired person has a reduced or completely lost desire to eat. Consequently, the body receives less energy - a vicious circle is obtained.

In case of chronic fatigue, intestinal upset can also be observed.

Overfatigue can work and, conversely, hyperactivity of the body. This situation leads to an even greater aggravation of the situation, since the body, contrary to logic, begins to spend even more energy, triggering the mechanism of self-destruction. And if, in order to relax, a person begins to use alcoholic beverages, the situation worsens, and the state of health only worsens.

Signs of fatigue in children begin to appear:

Weakening of differentiation in movements.

Decreased attention and accuracy of manipulations.

· Appears restlessness.

External signs of varying degrees of fatigue are divided:

Mild Fatigue Level:

o The skin is slightly rosy.

o Small amount of sweat droplets. They are localized mainly on the face in the forehead.

o The rhythm of breathing is a little quickened, but even, without interruptions. A person is able to breathe both through the mouth and through the nose.

Average level of fatigue:

o The skin becomes red.

o Profuse perspiration, which is clearly visible in the head and body.

o The intensity of respiratory activity increases, a person is able to breathe only through the oral cavity, the volume of nasal breathing is no longer enough.

o Coordination and motor skills remain within normal limits.

High level of fatigue - overwork:

o The skin turns pale quite sharply, in the triangle - the corners of the upper lip and nose - a clearly differentiated cyanosis appears, which has its own term in medicine - cyanosis.

o Profuse perspiration, which is clearly visible in the head and body. Salts that come out with sweat appear on clothes, which appear in the form of whitish spots.

o The intensity of respiratory activity increases. Inhalation and exhalation duplicate the shoulders.

o There is a lack of coordination of movement. In a person, both the upper and lower limbs begin to coward, the body sways slightly, and problems with movement may arise.

In order to support your body and not bring it to complete exhaustion, it is worth adjusting the regime by adopting some preventive measures:

Set aside time for outdoor walks before bed.

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

Avoid stressful situations.

Get at least eight hours of sleep a night.

It is necessary to remove bad habits from your life.

Human 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 to switch attention or alternate physical work with mental work, and vice versa.

CHAPTER 7

RATIONAL WORK AND REST

Labor is at the heart of the formation and development of man and the creation of material values. A rationally organized labor process has a beneficial effect on the health, physical, intellectual and moral improvement of people.

A person prepares for work in advance. Even before the start of labor, changes in the metabolism and energy, nervous, cardiovascular, respiratory and other systems are noted in the body. The leading role in preparing the body for labor activity belongs to the central nervous system, which ensures the coordination of functional changes. In the nerve centers of the cerebral cortex, the level of excitation processes increases, the functional state of the visual, auditory and other analyzers changes. Along with this, the processes of inhibition deepen, and a balance is established between excitation and inhibition.

During physical work, biochemical and biophysical processes occur in the muscles, ensuring their contraction. There is an increase in the number of heartbeats, an increase in systolic blood volume, an increase in maximum blood pressure, an increase in the mass of blood circulating in the body and the number of red blood cells, an increase in the frequency and depth of breathing. Under the influence of muscle load, the secretory and motor functions of the stomach are inhibited, the digestion and absorption of food slows down. At the end of the work, all the noted changes are gradually restored and return to normal during the rest period.

Any mental work is accompanied by neuro-emotional stress. Such characteristics of labor activity as the significance of work, its danger, responsibility lead to emotional stress. Primary functional changes in the human body during mental work occur, first of all, in higher nervous activity. During mental work, perception, attention, memory are sharpened. Neuro-emotional stress leads to an increase in cardiovascular activity, respiration, metabolism and energy, and an increase in muscle tone. The blood supply to the brain increases, the energy metabolism of nerve cells increases, the parameters of the bioelectrical activity of the brain change, and there is an increase in a- and b-rhythms. With mental work, the consumption of lipids increases. The process of excitation in the brain is associated with an increase in the oxidation of carbohydrates, with an increase in the exchange of ATP and phosphocreatine, and an increase in the renewal of phospholipids. In addition, when a person performs mental work, the electrical activity of the muscles increases, the activity of the sympathetic-adrenomedular, hypothalamic-pituitary, and cortical systems increases, there is an acceleration of the exchange of catecholamines, an increase in the release of norepinephrine in the sympathetic endings, an increase in the blood levels of adrenaline and corticosteroids that stimulate energy processes, changing mineral metabolism and increasing the excitability of neurons.

Mental work is closely connected with the work of the sense organs, primarily vision and hearing. The performance of mental work is significantly affected by the state of the environment, the intensity of muscle work. Usually, light muscular work stimulates mental activity, and hard, exhausting work reduces its quality. Therefore, for many representatives of mental activity, walking is a necessary condition for completing work.

With intensive intellectual activity, the brain's need for energy increases, accounting for 15-20% of the total metabolism in the body, while the weight of the brain is only 2% of body weight. At the same time, the oxygen consumption of 100 g of the cerebral cortex turns out to be 5-6 times greater than that consumed by a skeletal muscle of the same mass at maximum load. Daily energy consumption during mental work is 10.5 - 12.5 J. It should be noted that with certain types of mental activity, the increase in energy consumption is different. So, when reading aloud while sitting, energy consumption increases by 48%, when delivering a public lecture - by 94%, for computer operators - by 60-100%.

Prolonged mental stress has a depressing effect on mental activity: the functions of attention, memory, perception deteriorate, tachycardia, hypertension, ECG changes, an increase in pulmonary ventilation and oxygen consumption, the formation of paradoxical reactions, an increase in body temperature and other changes in autonomic functions.

Under the influence of excessive mental work, imbalances in the processes of inhibition and excitation occur, expressed in a disorder of positive inhibition of conditioned connections, the tone of smooth muscles of internal organs, blood vessels, especially those of the brain and heart, deviates from the norm. After intensive mental work, the content of phosphates in the blood and urine doubles.

During mental work, the brain is prone to inertia, to the continuation of mental activity in a given direction. Therefore, after the end of mental work, the “working dominant” does not completely fade away, causing a longer fatigue and exhaustion of the central nervous system during mental work than during physical work.

Fatigue and fatigue at work

In the process of doing physical work, fatigue- temporary decrease in performance. Fatigue is subjectively perceived as fatigue with a deterioration in well-being, decreased attention, impaired coordination of movements, palpitations, shortness of breath, and muscle pain. Fatigue is caused by intensive or prolonged activity and occurs more quickly with heavy intensive work. With light but monotonous physical labor, fatigue usually develops slowly. Fatigue is a reversible physiological state. The process of fatigue is accompanied by a decrease in the speed of motor reactions, drowsiness, a decrease in the tone of the blood vessels of the brain and heart, an increase in metabolism, a decrease in working capacity and labor productivity.

The physiological picture of physical and mental fatigue is similar. Mental and physical fatigue affect each other. So, with severe physical fatigue, mental work is unproductive, and, conversely, with mental fatigue, muscle performance decreases. It is generally accepted that these phenomena are due to the irradiation of inhibition from the most tired centers to neighboring ones. During mental activity, elements of muscle fatigue are constantly observed: a long stay in a certain position leads to significant fatigue of the corresponding parts of the motor apparatus.

With mental fatigue, more pronounced functional shifts were noted on the part of the central nervous system, higher nervous activity, analyzers and mental activity. There is a disorder of attention, deterioration of memory and thinking, the accuracy and coordination of movements are weakened.

The resumption of work against the background of slowly developing fatigue leads to the fact that the remaining traces of fatigue accumulate. Constant fatigue, non-restoration of working capacity by the beginning of a new working day can cause overwork.

Overwork is understood as a pathological condition characterized by a persistent decrease in working capacity. It leads to neurosis, the appearance and exacerbation of cardiovascular diseases, peptic ulcer disease, memory loss, weakening of attention, headaches, insomnia, loss of appetite, and a decrease in the body's resistance to environmental factors.

To maintain high efficiency and prevent fatigue in the process of work, the rational organization of work and rest is of great importance, in particular, the alternation of periods of work and rest, the organization of breaks and their correct use. The duration of breaks is set within 5-30 minutes. Rest during a scheduled break is more effective when it is active, filled with another activity.

Industrial gymnastics is a typical type of active recreation. For professions that perform standing work, it is advisable to replace gymnastics with foot massage. For sedentary professions, gymnastics should include exercises for the large muscles of the body and legs. Rest should also be active outside of working hours.

Of great importance is the mechanization and automation of production processes, the factors of the production environment, and the professionalism of workers. Since fatigue develops rapidly during static work, it is necessary to increase the dynamic component in any kind of activity, to ensure a rational working posture with the involvement of a minimum number of muscles.

Similar information.

Intensive mental work, both physical and mental, can lead to both fatigue and overwork.

Fatigue and overwork and their consequences.

Fatigue is understood as a special physiological state of the body that occurs after the work done and is expressed in a temporary decrease in performance.

Efficiency is the value of the functional capabilities of the human body, characterized by the quantity and quality of work performed in a certain time. During labor activity, the performance of the body changes over time. There are three main phases of successive states of a person in the process of labor activity:

Phase of development, or increasing efficiency; during this period, the level of performance gradually increases compared to the original; depending on the nature of labor and the individual characteristics of a person, this period lasts from several minutes to 1.5 hours, and with mental creative work - up to 2.2.5 hours;

Phase of high stability of working capacity; it is characterized by a combination of high labor indicators with relative stability or even some decrease in the intensity of physiological functions; the duration of this phase can be 2.2.5 hours or more, depending on the severity and intensity of labor;

The phase of decreased performance, characterized by a decrease in the functionality of the main working organs of a person and accompanied by a feeling of fatigue.

One of the objective signs is a decrease in labor productivity, but subjectively, it is usually expressed in a feeling of fatigue, i.e. in the unwillingness or even impossibility of further continuation of work. Fatigue can occur with any activity.

Fatigue is associated with changes in the physiological state of the whole organism as a result of prolonged or hard work, and disorders that occur in the central nervous system are of particular importance.

With prolonged exposure to the body of harmful factors of the production environment, overwork can develop, sometimes called chronic fatigue, when a night's rest does not fully restore the working capacity that has decreased during the day.

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

Symptoms of overwork are various disorders from the neuropsychic sphere, for example, weakening of attention and memory. Along with this, overworked people often experience headaches, sleep disorders (insomnia), loss of appetite and increased irritability.

In addition, chronic overwork usually causes a weakening of the body, a decrease in its resistance to external influences, which is expressed in an increase in morbidity and injuries. Quite often this condition predisposes to the development of neurasthenia and hysteria.

Prevention of fatigue and the main ways to improve the efficiency of human labor activity.

An important preventive measure is the substantiation and implementation of the most expedient mode of work and rest in production activities, i.e. a rational system of alternating periods of work and breaks between them.

There are two forms of alternating periods of work and rest at work: the introduction of a lunch break in the middle of the working day and short-term regulated breaks. The optimal duration of the lunch break is set taking into account the distance from the workplace to sanitary facilities, canteens, and the organization of food distribution. The duration and number of short-term breaks are determined on the basis of observations of the dynamics of working capacity, taking into account the severity and intensity of labor.

When performing work that requires significant effort and the participation of large muscles, more rare, but longer ones are recommended. 12 minute breaks. When performing particularly hard work (metallurgist, blacksmiths, etc.), you should combine work for 15-20 minutes with a rest of this duration. For work that requires a lot of nervous tension and attention, quick and precise hand movements, more frequent, but short 5-10-minute breaks are advisable.

In addition to regulated breaks, there are micropauses - breaks in work that occur spontaneously between operations and actions. Micropauses ensure that the optimal pace of work and a high level of performance are maintained. Depending on the nature and severity of the work, micropauses make up 9-10% of the working time.

High working capacity and vital activity of the organism is supported by a rational alternation of periods of work, rest and sleep of a person. During the day, the body reacts differently to physical and neuropsychic stress. In accordance with the daily cycle of the body, the highest performance is noted in the morning (from 8 to 12 h) and daytime (from 14 to 17 h) hours. In the daytime, the lowest performance, as a rule, is observed between 12 and 14 hours, and at night - from 3 to 4 hours, reaching its minimum. Taking into account these patterns, the shift work of enterprises, the beginning and end of work in shifts, breaks for rest and sleep are determined.

The alternation of periods of work and rest during the week should be regulated taking into account the dynamics of working capacity. The highest efficiency falls on the 2nd, 3rd and 4th day of work, on the following days of the week it decreases, falling to a minimum on the last day of work. On Monday, working capacity is relatively lowered due to workability.

One of the most important elements of increasing the efficiency of human labor activity is the improvement of skills and abilities as a result of labor training.

From the point of view of psychophysiological, industrial training is a process of adaptation and a corresponding change in the physiological functions of the human body for the most effective performance of a particular job. As a result of training (learning), muscle strength and endurance increase, the accuracy and speed of working movements increase, and physiological functions recover faster after work is completed.

The correct location and layout of the workplace, ensuring a comfortable posture and freedom of labor movements, the use of equipment that meets the requirements of ergonomics and engineering psychology ensure the most efficient work process, reduce fatigue and prevent the risk of occupational diseases.

The optimal posture of a person in the process of labor activity ensures high working capacity and labor productivity. Incorrect body position in the workplace leads to the rapid onset of static fatigue, a decrease in the quality and speed of the work performed, as well as a decrease in the reaction to hazards. The normal working posture should be considered one in which the worker does not need to lean forward more than 10 .15 °; tilting back and to the sides is undesirable; the main requirement for a working posture is a straight posture.

The main factor causing fatigue is the integral extensive intensity of activity (load). In addition to the absolute value of the load, a number of other factors affect the degree of development of fatigue, among which the following should be highlighted:
- static or dynamic nature of the load;
- The intensity of the load, i.e. its distribution in time;
- constant and rhythmic nature of the load.

Static physical activity, other things being equal, leads to a greater development of fatigue than dynamic, and the subjective feeling of fatigue in this case is especially pronounced.

The time of onset of fatigue and its severity depend on the degree of intensity of the load as follows: with an increase in the intensity of the load, fatigue occurs earlier, with a decrease in the intensity of the load, the time of onset of fatigue does not change (in the latter case, labor productivity is significantly reduced, which is disadvantageous). There is a certain optimal load intensity at which fatigue develops the slowest.

In addition to the magnitude of the load, there are a number of additional or contributing factors to the development of fatigue. By themselves, they do not lead to the development of fatigue, however, combined with the action of the main factor, they contribute to an earlier and more pronounced onset of fatigue. These factors can be divided into three large groups:
1) microclimate

2) use of technology

3) violation of the regime of work and rest.

The first group includes: reduced oxygen content in the inhaled air, increased carbon dioxide content, high ambient temperature, high humidity, changes in barometric pressure, etc.

The second troupe is characterized by the greatest diversity. Among the reasons included in this group, one should name a change in the composition of the air - its pollution with various gases (for example, products of incomplete combustion of fuel, etc.); the action of mechanical forces leading to vibration, shaking, acceleration, the impact of electromagnetic oscillations, noise and ultrasound, changes in illumination, inconvenience of the working posture and much more.

Finally, the third group includes factors that are mainly related to the violation of the regime of work and rest: lack of time to restore strength after fatigue, improper use of breaks between work, ill-conceived planning of work and rest.

Emotional factors strongly influence the development of fatigue. The severity and time of onset of fatigue of a person, his general and special physical development, etc.
Among the types of fatigue, it is necessary to specifically point out one specific type that occurs in the absence of activity. It is quite common in modern production among specialists whose activities are associated with the reception of irregularly and unexpectedly incoming information, i.e. operating in standby mode. This type of fatigue is intermediate between general and mental fatigue. The feeling of fatigue in these professionals is partly due to the static working posture, although it is mainly determined by the development of sensory tension.

The foregoing allows us to consider that the described phases are determined by a combination of physical and informational characteristics of the work. But there is another specific form of change in the functional state of the operator, to a lesser extent associated with physical characteristics. This is basically the reaction of the operator's body to the information structure of the system. This form of altered functional state is called specific tension.

The dynamics of working capacity, the dynamics of fatigue are non-specific manifestations of the body, a general reaction to the intensity and extensiveness of work activity, while the state of specific tension depends on the structure and content of the information flow in the MSM.

In this regard, the main criterion for assessing specific tension, or rather, assessing the nature of the body's reaction to the information structure of the working class of the process is the criterion of adequacy. The study was conditionally called the state of adequate mobilization and the state of dynamic mismatch.

Status of adequate mobilization- this is such a state of the operator, which is optimal or close to optimal for the given working conditions of a person included in a particular control system. The symptomatology and severity of this state depend primarily on the amount of information, its density and extensiveness, on the semantic significance of information, the nature of coding, the presence of noise, the required programs for implementing the received information, and the features of the controlled system. The more the required state differs from the state of operational rest, the more pronounced is active mobilization.
A characteristic feature of adequate mobilization is its linearity, i.e. the presence of a direct dependence on the subjective difficulty of the work performed.

The first step in diagnosing or predicting this condition is to quantify the information model of the workflow to find out which element of this activity primarily determines the degree of adequate mobilization. In most cases, the operational point for judgment is the position of the found characteristics on the scale of the limiting capabilities of a person.

Identification of the leading element of the activity solves the question of what property or properties of the operator determine its performance, and the state of the corresponding functions will primarily characterize the degree of adequate mobilization. However, in addition to this, the state of the systems of nonspecific support and regulatory nervous formations associated with the leading function also changes. Since the state of these systems does not distract the operator from performing the main duties, and the indicators themselves are quite closely correlated with the level of operation of the main system, the degree of tension is judged precisely by the state of these systems.
The state of adequate mobilization is characterized by a minimum number of errors in work and the choice of the optimal activity algorithm.

The question may arise: since the external signs of the stage of adequate mobilization are very close to that stage of working capacity, which was described as the compensation phase, is such a division not artificial? Of course, these states are similar in many respects, but two essential circumstances make it possible to separate them. Firstly, this is the connection of the state of adequate mobilization only with the information structure of the work: with an increase in the difficulty of work, the severity of the stage increases, with a decrease it weakens; the compensation phase is more stable and changes little with temporary fluctuations in the intensity of work. Secondly, it is not related to the time of work and can be equally expressed both at the beginning and at the end of it.

In those cases when the requirements imposed on the body are at the limit of its physiological capabilities or exceed them, there is a transition from the state of adequate mobilization to the state of dynamic mismatch. However, dynamic mismatch can occur with a small information load, when there are various emotional shifts, especially those associated with a small skill in work.

Dynamic Mismatch Status. With dynamic mismatch, the main regularity of the previous stage is violated - the level of work on the perception of information does not correspond to the expected physiological state. This state is evidenced by large shifts in vegetative reactions, the appearance of additional reactions, in particular sweating, vasodilation of the skin, impaired muscle balance, etc. This condition is extremely important for evaluating the work of a specialist, since it is accompanied by severe impairments in performance and the appearance of a large number of errors, unnecessary actions , an increase in the time of work, up to the refusal of work or its termination.
The generalized nature of the dynamic discrepancy leads to the fact that errors and incorrect actions are observed even when the operator must perform the actions required in the course of work that are simple for him, otherwise performed without fail. On this basis, one of the techniques for estimating the mismatch is based, when the operator is asked to perform a series of tests of increasing complexity in the course of work, which are usually well performed. The simpler the test, in which the difficulty or error appeared, the deeper the dynamic mismatch.

Dynamic Mismatch is more stable, when the operators were in a state of adequate mobilization, they produced six digits. In a state of dynamic mismatch, one of them could remember only four digits, and the other only two.

Dynamic Mismatch is more sustainable than adequate mobilization; a decrease in the intensity of the load does not lead to the elimination of this condition and the appearance of adequate mobilization. A certain time must pass before the signs of mismatch disappear.