Adaptation - ability to winter cold. Free adaptation to cold Spiritual practices to adapt cold and heat

- 2036

I'll tell you about one of the most incredible, from the point of view of everyday ideas, practices - the practice of free adaptation to the cold.

According to generally accepted ideas, a person cannot be in the cold without warm clothes. The cold is absolutely destructive, and as fate willed to go out into the street without a jacket, the unfortunate person is waiting for a painful freezing, and an inevitable bouquet of illnesses upon his return.

In other words, generally accepted concepts completely deny a person the ability to adapt to the cold. The comfort range is considered to be located exclusively above room temperature.

It seems that you can not argue. You can't spend the whole winter in Russia in shorts and a T-shirt ...

The fact of the matter is that you can !!

No, without clenching your teeth, overgrown with icicles to set a ridiculous record. And free. Feeling, on average, even more comfortable than others. This is a real hands-on experience that breaks conventional wisdom in a crushing way.

It would seem, why own such practices? Everything is very simple. New horizons always make life more interesting. Removing the instilled fears, you become freer.
The comfort range is expanding enormously. When the rest is hot, sometimes cold, you feel good everywhere. Phobias disappear completely. Instead of fear of getting sick, if you don't dress warmly enough, you get complete freedom and confidence in your abilities. Running in the cold is really nice. If you go beyond your powers, then this does not entail any consequences.

How is this even possible? Everything is very simple. We are much better organized than is commonly believed. And we have mechanisms that allow us to be free in the cold.

First, when the temperature fluctuates within certain limits, the metabolic rate, the properties of the skin, etc. change. In order not to dissipate heat, the outer contour of the body greatly lowers the temperature, while the core temperature remains very stable. (Yes, cold paws are normal !! No matter how we were convinced in childhood, this is not a sign of freezing!)

With an even greater cold load, specific mechanisms of thermogenesis are activated. We know about contractile thermogenesis, in other words, tremors. The mechanism is, in fact, an emergency. The shiver warms, but it turns on not from a good life, but when you really freeze.

But there is also non-contractile thermogenesis, which produces heat through the direct oxidation of nutrients in the mitochondria directly into heat. In the circle of people practicing cold practices, this mechanism was called simply "stove". When the "stove" is turned on, heat is regularly produced in the background in an amount sufficient for a long stay in the frost without clothes.

Subjectively, this feels rather unusual. In Russian, the word "cold" refers to two fundamentally different sensations: "cold outside" and "cold for you." They can be present independently. You can get cold in a warm enough room. And you can feel a burning cold outside on your skin, but do not freeze at all and not experience discomfort. Moreover, it is pleasant.

How does one learn to use these mechanisms? I will emphatically say that I consider "learning by article" risky. The technology must be handed over personally.

Non-contractile thermogenesis starts in a fairly severe frost. And its inclusion is quite inertial. The “stove” does not start working earlier than in a few minutes. Therefore, paradoxically, learning to walk freely in the cold is much easier in severe frost than on a cool autumn day.

As soon as you go out into the cold, you begin to feel the cold. At the same time, an inexperienced person is seized with panic horror. It seems to him that if it is already cold now, then in ten minutes a full paragraph will come. Many simply do not wait for the "reactor" to reach operating mode.

When the “stove” starts, it becomes clear that, contrary to expectations, it is quite comfortable to be in the cold. This experience is useful in that it immediately breaks the patterns inspired from childhood about the impossibility of such a thing, and helps to look differently at reality as a whole.

For the first time, you need to go out into the cold under the guidance of a person who already knows how to do it, or where you can return to the warmth at any time!

And you need to go out extremely naked. Shorts, even better without a shirt and nothing else. The body needs to be properly scared so that it turns on forgotten adaptation systems. If you get scared and put on a sweater, trowel, or something like that, then the heat loss will be enough to freeze very much, but the "reactor" will not start!

For the same reason, gradual "hardening" is dangerous. A decrease in the temperature of the air or bath "by one degree in ten days" leads to the fact that sooner or later the moment comes when it is already cold enough to get sick, but not enough to trigger thermogenesis. Truly, only iron people can withstand such hardening. But almost everyone can go straight out into the cold or dive into an ice-hole.

After what has been said, one can already guess that adaptation not to frost, but to low above-zero temperatures is a more difficult task than jogging in frost, and it requires more high training... The "stove" at +10 does not turn on at all, and only non-specific mechanisms work.

It should be remembered that severe discomfort cannot be tolerated. When everything works out correctly, no hypothermia develops. If you start to get very cold, then you need to interrupt the practice. Periodic going beyond the limits of comfort is inevitable (otherwise it will not be possible to push these limits), but the extreme should not be allowed to grow into a kick-ass.

The heating system gets tired of working under load over time. The limits of endurance are very far. But they are. You can walk freely at -10 all day, and at -20 for a couple of hours. But you won't be able to go on a ski trip in one T-shirt. (Field conditions are a separate topic altogether. weather. But, with experience)

For greater comfort, it is better to walk in more or less clean air, away from sources of smoke and from smog - the sensitivity to what we breathe in this state increases significantly. It is clear that practice is generally incompatible with smoking and booze.

Being in the cold can cause cold euphoria. The feeling is pleasant, but requires extreme self-control in order to avoid loss of adequacy. This is one of the reasons why it is highly undesirable to start the practice without a teacher.

Another important nuance is a prolonged reboot of the heating system after significant loads. Having picked up the cold properly, you can feel pretty good, but when you enter a warm room, the "stove" turns off, and the body begins to warm up with tremors. If, at the same time, you go out into the cold again, the "stove" will not turn on, and you can get very cold.

Finally, you need to understand that mastery of practice does not guarantee that you will not freeze anywhere and never. The condition changes and many factors affect. But, the likelihood of getting into trouble from the weather is still reduced. Just as the likelihood of being physically deflated for an athlete is differently lower than that of a squishy.

Alas, it was not possible to create a complete article. I just outlined this practice in general terms (more precisely, a complex of practices, because diving into an ice hole, jogging in a T-shirt in the cold and strolling through the woods in the Mowgli style are different). Let me summarize where I started. Owning your own resources allows you to get rid of fears and feel much more comfortable. And this is interesting.

Content
I. Introduction

II. Main part

1. Optium and pessium. The sum of the efficiency of the temperatures

2. Poikilothermic organisms

2.1 Passive resistance

2.2 Metabolic rate

2.3 Temperature adaptations

3. Homeothermal organisms

3.1 Body temperature

3.2 Mechanism of thermoregulation

Bibliography
I. Introduction
Organisms are real carriers of life, discrete units of metabolism. In the process of metabolism, the body consumes the necessary substances from the environment and releases metabolic products into it, which can be used by other organisms; dying, the body also becomes a source of nutrition for certain types of living beings. Thus, the activity of individual organisms underlies the manifestation of life at all levels of its organization.

The study of fundamental metabolic processes in a living organism is a subject of physiology. However, these processes take place in a complex, dynamic environment of the natural habitat, are under the constant influence of a complex of its factors. Maintaining a stable metabolism in fluctuating environmental conditions is impossible without special adaptations. The study of these adaptations is a task for ecology.

Adaptations to environmental factors can be based on the structural features of the organism - morphaological adaptations - or on specific forms of functional response to external influences - physiological adaptations. In higher animals, higher nervous activity plays an important role in adaptation, on the basis of which adaptive forms of behavior - ecological adaptations - are formed.

In the field of studying adaptations at the level of the organism, the ecologist comes into the closest interaction with physiology and applies many physiological methods. However, applying physiological methods, ecologists use them to solve their specific problems: the ecologist is primarily interested not in the fine structure of the physiological process, but in its final result and the dependence of the process on the influence of external factors. In other words, in ecology, physiological indicators serve as criteria for the body's response to external conditions, and physiological processes are considered primarily as a mechanism that ensures the uninterrupted implementation of fundamental physiological functions in a complex and dynamic environment.
II. MAIN PART
1. Optimum and pessimum. Sum of effective temperatures
Any organism is capable of living within a certain temperature range. The temperature range on the planets of the solar system is thousands of degrees, and the limits are. In which the life we ​​know can exist are very narrow - from -200 to + 100 ° C. Most species live in an even narrower temperature range.

Some organisms. Especially in the resting stage, they can exist at very low temperatures, and certain types of microorganisms are able to live and multiply in urban springs at temperatures close to the boiling point. The range of temperature fluctuations in water is usually less than on land. The range of tolerance changes accordingly. Zoning and stratification are often associated with temperature in both water and terrestrial habitats. The degree of temperature variability and its fluctuations are also important, that is, if the temperature changes in the range from 10 to 20 C and the average value is 15 C, this does not mean that the fluctuating temperature has the same effect as the constant one. Many organisms thrive in varying temperatures.

Optimal conditions are those under which all physiological processes in the body or ecosystems run with maximum efficiency. For most species, the temperature optimum is in the range of 20-25 ° С, slightly shifting in one direction or another: in the dry tropics it is higher - 25-28 ° С, in temperate and cold zones below - 10-20 ° С. In the course of evolution, adapting not only to periodic changes in temperature, but also to regions of different heat supply, plants and animals have developed different needs for heat in different periods of life. Each species has its own optimal temperature range, and for different processes (growth, flowering, fruiting, etc.) there are also "their" values ​​of the optima.

It is known that physiological processes in plant tissues begin at a temperature of + 5 ° C and are activated at + 10 ° C and above. In coastal forests, the development of spring species is especially clearly associated with average daily temperatures from -5 ° C to + 5 ° C. A day or two before the temperature passes through -5 ° C, under the forest litter, the development of the star spring and Amur adonis begins, and during the transition through 0 ° C, the first flowering individuals appear. And even at an average daily temperature of + 5 ° C, both species bloom. Due to the lack of heat, neither adonis nor the spring plant form a continuous cover, they grow singly, less often - several individuals together. A little later than them - with a difference of 1-3 days, anemones start to grow and bloom.

Temperatures "lying" between lethal and optimal are considered pessimal. In the pessimum zone, all life processes are very weak and very slow.

The temperatures at which active physiological processes take place are called effective, their values ​​do not go beyond the lethal temperatures. The sum of effective temperatures (ET), or the sum of heat, is a constant value for each species. It is calculated by the formula:
ET = (t - t1) × n,
Where t is the ambient temperature (actual), t1 is the temperature of the lower threshold of development, often 10 ° C, n is the duration of development in days (hours).

It was revealed that each phase of the development of plants and ectothermic animals begins at a certain value of this indicator, provided that other factors are also at optimum. So, the bloom of coltsfoot occurs at a sum of temperatures of 77 ° С, strawberries - at 500 ° С. The sum of effective temperatures (ET) for the entire life cycle allows to identify the potential geographic range of any species, as well as to make a retrospective analysis of the distribution of species in the past. For example, the northern limit of woody vegetation, in particular of Cajander larch, coincides with the July isotherm of + 12 ° С and the total ET above 10 ° С - 600 °. For early crops, the total ET is 750 °, which is quite enough for growing early varieties of potatoes even in the Magadan region. And for Korean cedar, the total ET is 2200 °, for whole-leaved fir - about 2600 °, therefore both species grow in Primorye, and fir (Abies holophylla) - only in the south of the region.
2. POYKILOTHERM ORGANISMS
Poikilothermic (from the Greek poikilos - changeable, changing) organisms include all taxa organic world except for two classes of vertebrates - birds and mammals. The name underlines one of the most noticeable properties of the representatives of this group: instability, their body temperature, varying widely depending on changes in ambient temperature.

Body temperature . The principal feature of heat exchange in poikilothermic organisms is that, due to their relatively low metabolic rate, external heat is their main source of energy. This explains the direct dependence of the body temperature of poikilotherms on the temperature of the environment, more precisely on the influx of heat from the outside, since terrestrial poikilothermic forms also use radiation heating.

However, full correspondence between body and environmental temperatures is rarely observed and is characteristic mainly of organisms of very small sizes. In most cases, there is some discrepancy between these indicators. In the range of low and moderate ambient temperatures, the body temperature of organisms that are not in a state of numbness turns out to be higher, and in very hot conditions, it is lower. The reason for the excess body temperature over the environment is that even with a low level of metabolism, endogenous heat is produced - it causes an increase in body temperature. This is manifested, in particular, in a significant increase in temperature in actively moving animals. For example, in insects at rest, the excess of body temperature over the environment is expressed in tenths of a degree, while in actively flying butterflies, bumblebees and other species, the temperature is maintained at a level of 36 - 40 "C even when the air temperature is below 10" C.

The temperature lower than the environment during heat is characteristic of terrestrial organisms and is explained primarily by the loss of heat with evaporation, which increases significantly at high temperature and low humidity.

The rate of change in body temperature of poikilotherms is associated inversely with their sizes. This is primarily determined by the ratio of mass and surface: in larger forms, the relative surface of the body decreases, which leads to a decrease in the rate of heat loss. This is of great ecological importance, determining for different species the possibility of settling in geographic areas or biotopes with certain temperature regimes. It has been shown, for example, that large leatherback turtles caught in cold waters had a temperature in the depths of the body - 18 "C higher than the temperature of the water; it is the large size that allows these turtles to penetrate into the colder regions of the ocean, which is not characteristic of smaller species.
2.1 Passive resistance
The considered regularities cover the range of temperature changes, within which active vital activity is maintained. Outside this range, which vary widely in different species and even geographic populations of the same species, active forms of activity of poikilothermic organisms cease, and they pass into a state of numbness, characterized by a sharp decrease in the level of metabolic processes, up to a complete loss of visible manifestations of life. In such a passive state, poikilothermic organisms can tolerate a sufficiently strong increase and an even more pronounced decrease in temperature without pathological consequences. The basis of such temperature tolerance lies in a high degree of tissue stability, inherent in all poikilothermic species and often supported by severe dehydration (seeds, spores, some small animals).

The transition to a state of numbness should be considered as an adaptive response: an almost non-functioning organism is not exposed to many damaging influences, and also does not consume energy, which allows it to survive under adverse temperature conditions for a long time. Moreover, the very process of transition to a state of torpor can be a form of active rearrangement, such as a reaction to temperature. "Hardening" of frost-resistant plants is an active seasonal process that goes in stages and is associated with rather complex physiological and biochemical changes in the body. In animals, falling into a torpor in natural conditions is often also expressed seasonally and is preceded by a complex of physiological rearrangements in the body. There is evidence that the process of transition to stupor can be regulated by some hormonal factors; objective material on this matter is not yet sufficient for broad conclusions.

When the temperature of the environment goes beyond the limits of tolerance, the death of the organism occurs from the reasons discussed at the beginning of this chapter.
2.2 Metabolic rate
Temperature variability entails corresponding changes in the rate of metabolic reactions. Since the dynamics of the body temperature of poikilothermic organisms is determined by changes in the temperature of the environment, the intensity of metabolism is also directly dependent on the external temperature. The rate of oxygen consumption, in particular, with rapid changes in temperature, follows these changes, increasing with an increase and decreasing with a decrease. The same applies to other physiological functions: heart rate, intensity of digestion, etc. In plants, depending on the temperature, the rate of water and nutrient intake through the roots changes: an increase in temperature to a certain limit increases the permeability of protoplasm to water. It has been shown that with a decrease in temperature from 20 to 0 "C, the absorption of water by roots decreases by 60 - 70%. As in animals, an increase in temperature causes an increase in respiration in plants.

The last example shows that the effect of temperature is not straightforward: upon reaching a certain threshold, the stimulation of the process is replaced by its suppression. This is a general rule due to the approach to the threshold of normal life.

In animals, the dependence on temperature is very noticeably expressed in changes in activity, which reflects the total reaction of the organism, and in poikilothermic forms it depends in the most significant way on temperature conditions. It is well known that insects, lizards and many other animals are most mobile during the warm time of the day and on warm days, while in cool weather they become lethargic and inactive. The beginning of them vigorous activity is determined by the rate of warming up of the body, which depends on the temperature of the environment and on direct solar irradiation. The level of mobility of active animals, in principle, is also related to the ambient temperature, although in the most active forms this connection can be “masked” by endogenous heat production associated with the work of the muscles.

2.3 Temperature adaptations

Poikilothermic living organisms are widespread in all environments, occupying habitats of different temperature conditions, up to the most extreme: they practically inhabit the entire temperature range recorded in the biosphere. Keeping in all cases the general principles of temperature reactions (discussed above), different species and even populations of the same species exhibit these reactions in accordance with the characteristics of the climate, adapting the body's responses to a certain range of temperature effects. This is manifested, in particular, in the forms of resistance to heat and cold: species living in colder climates are more resistant to low temperatures and less to high; inhabitants of hot regions show opposite reactions.

It is known that tropical forest plants are damaged and die at temperatures of + 5 ... + 8 ° C, while the inhabitants of the Siberian taiga can withstand complete freezing in a state of numbness.

Various species of kart-toothed fish showed a clear correlation of the upper lethality threshold with water temperature in the species-specific water bodies.

Arctic and Antarctic fish, on the other hand, show high resistance to low temperatures and are very sensitive to its rise. So, Antarctic fish die when the temperature rises to 6 "C. Similar data have been obtained for many species of poikilothermic animals. For example, observations on the island of Hokkaido (Japan) showed a clear relationship between the cold resistance of several species of beetles and their larvae with their winter ecology: the most resistant In the experiments with amoeba it was found that their heat resistance directly depends on the temperature of cultivation.
3. HOMOYOTHERMAL ORGANISMS
This group does not include two classes of higher vertebrates - birds and mammals. The fundamental difference between the heat exchange of homeothermal animals and poikilothermic animals is that their adaptation to changing temperature conditions of the environment is based on the functioning of a complex of active regulatory mechanisms for maintaining thermal homeostasis of the internal environment of the body. Due to this, biochemical and physiological processes always take place under optimal temperature conditions.

The homeothermal type of heat exchange is based on the high metabolic rate inherent in birds and mammals. The metabolic rate of these animals is one to two orders of magnitude higher than that of all other living organisms at the optimum ambient temperature. So, in small mammals, oxygen consumption at an ambient temperature of 15 - 0 "C is approximately 4 - thousand cm 3 kg -1 h -1, and in invertebrates at the same temperature - 10 - 0 cm 3 kg -1 h -1 With the same body weight (2.5 kg), the daily metabolism of a rattlesnake is 32.3 J / kg (382 J / m2), in a marmot - 120.5 J / kg (1755 J / m2), in a rabbit - 188.2 J / kg (2600 J / m 2).

A high metabolic rate leads to the fact that in homeothermal animals, the basis of the heat balance is the use of their own heat production, the value of external heating is relatively small. Therefore, birds and mammals are classified as endothermic "organisms. Endothermy is an important property, due to which the dependence of the body's vital activity on the temperature of the external environment is significantly reduced.
3.1 Body temperature
Homeothermal animals are not only provided with heat due to their own heat production, but are also able to actively regulate its production and consumption. Due to this, they are characterized by a high and fairly stable body temperature. In birds, the deep body temperature is normally about 41 "C with fluctuations in different species from 38 to 43.5" C (data for 400 species). Under conditions of complete rest (basal metabolism), these differences are somewhat smoothed out, ranging from 39.5 to 43.0 "C. At the level of an individual organism, the body temperature shows a high degree of stability: the range of its daily changes usually does not exceed 2 - ~ 4" C, moreover, these fluctuations are not associated with air temperature, but reflect the rhythm of metabolism. Even in the Arctic and Antarctic species at ambient temperatures up to 20 - 50 "C frost, the body temperature fluctuates within the same 2 - 4" C.

An increase in ambient temperature is sometimes accompanied by a slight increase in body temperature. If pathological conditions are excluded, it turns out that under conditions of living in a hot climate, a certain degree of hyperthermia can be adaptive: in this case, the difference in body and environmental temperatures decreases and water consumption for evaporative thermoregulation decreases. A similar phenomenon has been noted in some mammals: in a camel, for example, with a water shortage, the body temperature can rise from 34 to 40 "C. In all such cases, an increased tissue resistance to hyperthermia is noted.

In mammals, body temperature is slightly lower than in birds, and in many species it is subject to greater fluctuations. Different taxa also differ in this indicator. In monotremes, rectal temperature is 30 - 3 "C (at an ambient temperature of 20" C), in marsupials it is slightly higher - about 34 "C at the same external temperature. In representatives of both these groups, as well as in non-edentulous, fluctuations in body temperature are quite noticeable in connection with the external temperature: with a decrease in air temperature from 20 - 5 to 14 - 15 "C, a drop in body temperature by more than two degrees was recorded, and in some cases even by 5" C. In rodents, the average body temperature in an active state fluctuates within 35 - 9.5 "С, in most cases being 36 - 37" С. external temperature from 0 to 35 "C.

In ungulates and carnivores, body temperature is maintained very steadily at the level characteristic of the species; interspecies differences usually fall within the range from 35.2 to 39 "C. For many mammals, a decrease in temperature during sleep is characteristic; the magnitude of this decrease varies in different species from tenths of a degree to 4 -" C.

All of the above refers to the so-called deep body temperature, which characterizes the thermal state of the thermostated "core" of the body. In all homeothermic animals, the outer layers of the body (integument, part of the musculature, etc.) form a more or less pronounced "shell", the temperature of which varies within wide limits. Thus, the stable temperature characterizes only the area of ​​localization of important internal organs and processes. Surface tissues can withstand more pronounced temperature fluctuations. This can be beneficial for the organism, since in such a situation the temperature gradient at the border of the organism and the environment decreases, which makes it possible to maintain the thermal homeostasis of the “core” of the organism with less energy expenditure.
3.2 Mechanisms of thermoregulation
Physiological mechanisms providing thermal homeostasis of the body (its "nucleus") are subdivided into two functional groups: mechanisms of chemical and physical thermoregulation. Chemical thermoregulation is the regulation of the body's heat production. Heat is constantly generated in the body during the redox reactions of metabolism. At the same time, part of it is given to the external environment, the more, the greater the difference between the temperature of the body and the environment. Therefore, maintaining a stable body temperature with a decrease in the temperature of the environment requires a corresponding increase in metabolic processes and the accompanying heat generation, which compensates for heat loss and leads to the preservation of the general heat balance of the body and maintaining the constancy of the internal temperature. The process of reflex enhancement of heat production in response to a decrease in ambient temperature is called chemical thermoregulation. The release of energy in the form of heat accompanies the functional load of all organs and tissues and is characteristic of all living organisms. The specificity of homeothermal animals is that a change in heat production as a reaction to a changing temperature represents a special reaction of the organism in them, which does not affect the level of functioning of the main physiological systems.

Specific thermoregulatory heat production is concentrated mainly in skeletal muscles and is associated with special forms of muscle functioning that do not affect their direct motor activity. An increase in heat generation during cooling can also occur in a resting muscle, as well as when the contractile function is artificially turned off by the action of specific poisons.

One of the most common mechanisms of specific thermoregulatory heat production in muscles is the so-called thermoregulatory tone. It is expressed by microcontractions of fibrils, recorded as an increase in the electrical activity of an externally immobile muscle when it is cooled. Thermoregulatory tone increases the oxygen consumption of the muscle, sometimes by more than 150%. With stronger cooling, along with a sharp increase in thermoregulatory tone, visible muscle contractions in the form of cold shiver are included. In this case, gas exchange increases to 300 - 400%. It is characteristic that in terms of the share of participation in thermoregulatory heat production, muscles are unequal. In mammals, the most important role is played by the chewing muscles and muscles that support the animal's posture, that is, they function mainly as tonic muscles. A similar phenomenon is observed in birds.

With prolonged exposure to cold, the contractile type of thermogenesis can be replaced (or supplemented) to one degree or another by switching tissue respiration in the muscle to the so-called free (non-phosphorylating) pathway, in which the phase of formation and subsequent breakdown of ATP falls out. This mechanism is not associated with muscle contractile activity. The total mass of heat released during free breathing is practically the same as in yeast thermogenesis, but most of the heat energy is consumed immediately, and oxidative processes cannot be inhibited by a lack of ADP or inorganic phosphate.

The latter circumstance makes it possible to freely maintain a high level of heat generation for a long time.

In mammals, there is another form of non-yeast thermogenesis associated with the oxidation of a special brown adipose tissue deposited under the skin in the interscapular space, neck and thoracic spine. Brown fat contains a large number of mitochondria and is penetrated by numerous blood vessels. Under the influence of cold, the blood supply to brown fat increases, its respiration intensifies, and the release of heat increases. It is important that in this case the organs located nearby are directly heated: the heart, large vessels, lymph nodes, as well as the central nervous system. Brown fat is mainly used as a source of emergency heat generation, in particular when warming up the body of animals coming out of hibernation. The role of brown fat in birds is not clear. For a long time it was believed that they did not have it at all; Recently, there have been reports of the discovery of this type of adipose tissue in birds, but neither precise identification nor functional assessment has been carried out.

Changes in the intensity of metabolism caused by the influence of ambient temperature on the body of homeothermal animals are natural. In a certain range of external temperatures, heat production corresponding to the exchange of a resting organism is completely compensated by its "normal" (without active intensification) heat transfer. The heat exchange between the body and the environment is balanced. This temperature range is called the thermoneutral zone. The exchange rate in this zone is minimal. They often speak of a critical point, implying a specific temperature value at which a heat balance with the environment is achieved. Theoretically, this is true, but it is practically impossible to establish such a point experimentally due to constant irregular fluctuations in metabolism and instability of the heat-insulating properties of the covers.

A decrease in the temperature of the environment outside the thermoneutral zone causes a reflex increase in the level of metabolism and heat production until the heat balance of the body is balanced under new conditions. Because of this, the body temperature remains unchanged.

An increase in the temperature of the environment outside the thermoneutral zone also causes an increase in the level of metabolism, which is caused by the activation of mechanisms for activating heat transfer, which require additional energy consumption for their work. Thus, a zone of physical thermoregulation is formed, during which the temperature of the takyre remains stable. Upon reaching a certain threshold, the mechanisms for enhancing heat transfer turn out to be ineffective, overheating begins and, ultimately, the death of the organism.

Species differences in chemical thermoregulation are expressed in the difference in the level of the main (in the zone of thermoneutrality) metabolism, the position and width of the thermoneutral zone, the intensity of chemical thermoregulation (an increase in metabolism with a decrease in the temperature of the medium by 1 "C), as well as in the range of effective action of thermoregulation. All these parameters reflect ecological specificity of individual species and adaptively change depending on the geographic location of the region, season of the year, altitude and a number of other environmental factors.

Physical thermoregulation combines a complex of morphophysiological mechanisms associated with the regulation of heat transfer from the body as one of the constituent parts of its overall heat balance. The main device that determines general level heat transfer from the body of a homeothermal animal, - the structure of the heat-insulating covers. Thermal insulating structures (feathers, hair) do not cause homeothermia, as is sometimes thought. It is based on high and that, by reducing heat loss, it contributes to the maintenance of homeothermy with lower energy costs. This is especially important when living in conditions of stably low temperatures; therefore, heat-insulating integumentary structures and layers of subcutaneous fat are most pronounced in animals from regions of cold climates.

The mechanism of the heat-insulating action of feathers and hairs is that groups of hair or feathers, located in a certain way, different in structure, hold a layer of air around the body, which acts as a heat insulator. Adaptive changes in the heat-insulating function of integuments are reduced to a restructuring of their structure, including the ratio of different types of hair or feathers, their length and density. It is by these parameters that the inhabitants of different climatic zones differ, they also determine the seasonal changes in thermal insulation. It has been shown, for example, that in tropical mammals the thermal insulation properties of the coat are almost an order of magnitude lower than in the inhabitants of the Arctic. The same adaptive direction is followed by seasonal changes in the heat-insulating properties of the covers during molting.

The considered features characterize the stable properties of heat-insulating covers, which determine the overall level of heat losses, and, in essence, do not represent active thermoregulatory reactions. The possibility of labile regulation of heat transfer is determined by the mobility of feathers and hair, due to which, against the background of a constant structure of the cover, rapid changes in the thickness of the heat-insulating air layer, and, accordingly, in the intensity of heat transfer are possible. The degree of looseness of hair or feathers can change rapidly depending on the temperature of the air and on the activity of the animal itself. This form of physical thermoregulation is referred to as the pilomotor reaction. This form of regulation of heat transfer acts mainly at low ambient temperatures and provides no less quick and effective response to thermal imbalances than chemical thermoregulation, while requiring less energy.

Regulatory reactions aimed at maintaining a constant body temperature during overheating are represented by various mechanisms for enhancing heat transfer to the external environment. Among them, heat transfer is widespread and highly efficient by intensifying the evaporation of moisture from the surface of the body and / or upper respiratory tract. When moisture evaporates, heat is consumed, which can help maintain heat balance. The reaction turns on when there are signs of starting overheating of the body. So, adaptive changes in heat transfer in homeothermal animals can be aimed not only at maintaining high level metabolism, as in most birds and mammals, but also on the installation of a low level in conditions that threaten the depletion of energy reserves.
Bibliography
1. Fundamentals of ecology: Textbook VV Mavrishchev. Minsk: Vysh. Shk., 2003 .-- 416 p.

2.http: \\ Abiotic factors of the environment.htm

3.http: \\ Abiotic environmental factors and organisms.htm

480 RUB | UAH 150 | $ 7.5 ", MOUSEOFF, FGCOLOR," #FFFFCC ", BGCOLOR," # 393939 ");" onMouseOut = "return nd ();"> Dissertation - 480 rubles, delivery 10 minutes, around the clock, seven days a week

Gerasimova Lyudmila Ivanovna. The pathogenetic role of maladjustment to cold in the development of prenosological conditions in the North: dissertation ... Doctors of Medical Sciences: 14.00.16 / Gerasimova Lyudmila Ivanovna; [Place of defense: GOUVPO "St. Petersburg State Medical University"] .- St. Petersburg, 2008.- 242 p .: ill.

Introduction

Chapter 1. Literature review 16

1.1. The concept of health in the aspect of adaptation theory 16

1.2. Adaptation to cold in humans 21

1.3. Negative effects of cold adaptation. Cold as a risk factor 41

1.4. Age features of the thermoregulation function 53

Chapter 2. Objects and methods of research 57

2.1. Groups surveyed 57

2.2. Research conditions, control of the thermal state of the subjects 58

2.3. Biometric Research 59

2.4. Method of dosing load and fatigue 61

2.5. Electroneuromyographic research techniques.61

2.6. Analysis of the frequency of cold-associated symptoms 78

2.7. Respiratory function assessment 80

2.8. Analysis of evoked cutaneous vegetative potentials 83

2.9. Statistical processing of research results 87

Chapter 3. Cold-associated symptoms as a sign of decreased cold resistance . 88

3.1. Impact of length of residence in the European North on the incidence of cold-associated symptoms 88

3.2. Frequency of cold-associated symptoms in patients with therapeutic pathology 96

3.3. Factors limiting the performance of hands when handling in the cold 105

Chapter 4. The functional state of pulmonary ventilation and autonomic nervous system with high sensitivity to cold 115

4.1. Functional indicators of the external respiration system in individuals with different adaptations to the conditions of the European North 117

4.2. Influence of adaptation to the conditions of the European North on the parameters of the evoked cutaneous vegetative potential 125

Chapter 5. Influence of adaptation to northern conditions on the conductive properties of peripheral nerves 133

Chapter 6. Electromyographic characteristics of neuromuscular status in different age groups in the European North 139

6.1. Evaluation of neuromuscular status using turn-amplitude analysis IEMG 139

6.2. Age features of turn-amplitude parameters of EMG of isometric contraction 155

6.3. Influence of age on working capacity and turn-amplitude characteristics of EMG during fatigue caused by dynamic load 166

Chapter 7. Electroneuromyographic characteristics and performance of the motor system under prolonged exposure to industrial vibration, 175

7.1. Parameters of impulse conduction along motor and sensory fibers of peripheral nerves 176

7.2. Parameters of potentials of motor units 177

7.3. Turn-amplitude characteristics of EMG with dosed isometric contraction 183

7.4. Influence of prolonged exposure to vibration on performance and turn-amplitude parameters of EMG during dynamic fatigue 188

Chapter 8. Discussion of Results 199

Conclusion 228

References 235

Appendix 282

Introduction to work

The urgency of the problem

The problem of preserving the health of a person living in the North remains relevant over the last time, which is associated with the active development of territories, an increase in migration processes in Russia, an increase in the proportion of the elderly population, including in the North-West region. Human health in the North is formed under the influence of the complex effect of all components of the high latitude climate. A complex set of external influences, including severe natural and climatic factors, a wide range of anthropogenic influences place high demands on the body. The preservation of human health, the prevention of diseases is becoming not only a particular problem of medicine, but also of natural science in general, as well as one of the general humanitarian values. ... Negative tendencies in changes in the health indicators of the population and the state of the human environment put this problem in the category of the most priority tasks of state policy.

In the harsh climatic conditions of high latitudes, many diseases are characterized by an early onset, nonspecific symptoms, and a greater prevalence of impaired functional states of the body than in other climatic zones. A significant place in morbidity is occupied by diseases of systemic overvoltage, the threshold of harmful effects on the body of production and environmental factors decreases and the body's functional capabilities to restore homeostasis disorders decrease, since, according to Yu.P. Gichev, the impact of external factors on the body of a modern person exceeds its adaptive capabilities ...

As shown in the review by V.I.Khasnulina et al. The Republic of Karelia, a region of the North-West of the Russian Federation, is distinguished by the discomfort of climatic and geographical conditions, which is comparable to that in the regions of the Far North, which causes stress in adaptation systems, complicates compensation and increases the overall mortality rate, including for people of working age. Similar data on the state of health of the population of the Republic of Karelia are given in the monograph by N.V. Dorshakova.

Thus, the data of numerous studies indicate that the state of health of the population living in the regions of the North is characterized by systemic manifestations of maladjustment of the body, an important role in which, in our opinion, is played by inadequacy of adaptation to cold.

It seems appropriate to consider the peculiarities of the body's functioning in the North from the point of view of the adequacy of the mechanisms of temperature adaptation. Adaptation to prolonged exposure to cold affects almost all vital processes, which are coordinated within the framework of a single program for maintaining the body's temperature homeostasis. Numerous studies have shown neuro-hormonal mechanisms for controlling the process of adaptation to cold, aimed at preserving homeothermia, which is based on systemic changes in neuro-hormonal regulation and metabolism, in which the increased participation of adrenergic mechanisms and changes in the thyroid status of the organism are of prime importance.

The manifestations of the negative effect of cold in various body systems are combined into the concept of “cold-associated symptoms” (CAS), which includes pain (discomfort), disturbances in sensitivity and discoloration of open parts of the body, as well as signs of functional insufficiency of the physiological systems of the body. Raynaud's phenomenon

7, which combines the listed signs, is considered one of the specific manifestations of cold intolerance.

Many authors have noted that Raynaud's phenomenon has common pathogenetic mechanisms with cold-induced vasoconstriction, the basis of which is an increase in vascular adrenoreactivity. This explains the difficulties of differential diagnosis of early manifestations of Raynaud's phenomenon and increased cold-induced vasoconstriction, in the occurrence of which, like Raynaud's phenomenon, in addition to these factors, impairments of endothelium-dependent and endothelium-independent vasodilation play a role.

Recent studies in the field of determining risk factors for the population of high latitudes have shown that the prevalence of Raynaud's phenomenon is, according to various sources, from 0.5 to 20%, there is a dependence of the frequency of Raynaud's phenomenon on the latitude of the area, a relationship has been established between the presence of this symptom and the frequency of Cold damage (frostbite), as well as the possibility of participation of the mechanisms of the development of Raynaud's phenomenon in the formation of human somatic diseases, the dependence of electroneuromyographic parameters on the presence of secondary (induced by vibration) Raynaud's phenomenon was noted. These facts, as well as the common origin of cold-induced vasoconstriction and Raynaud's phenomenon, based on the increased activity of adrenergic mechanisms, allow us to regard HAS as signs of intense adaptation to cold and risk factors for the population living in the North.

The morpho-functional state of the motor system and its main effector organ - skeletal muscles - plays an important role both in the reactions of urgent and long-term adaptation to cold. Experimental studies have shown the involvement and nature of the participation of the motor system in maintaining the temperature homeostasis of the body. At the same time, there are no data in the literature that integratively characterize the neuromuscular status of a person during long-term adaptation to cold and the peculiarities of the functioning of the motor system from the point of view of the adequacy of the process of adaptation to cold.

Electromyography is one of the most informative modern methods for assessing the functional state of the motor system, therefore, the study of interference electromyogram (IEMG) allows you to obtain an objective picture of the state of the neuromuscular system and supplement the data of other diagnostic methods. Recently, there has been a significant increase in the interest of researchers in the use and development of objective methods for interpreting IEMG, given its non-invasiveness, good tolerance and the possibility of using it in ergonomic studies, including for assessing the functional state and performance of the human motor system in various activities and for diagnostic purposes. ...

The problem of prenosological conditions, or "pre-disease", has long been in the focus of clinical medicine. Moreover, recently great importance is given to the identification of changes in the body corresponding to the initial link in the pathogenesis of a particular disease. In this regard, the modern scientific concept of assessing and predicting the functional states of the body is of interest for medicine and for society as a whole, since it allows detecting prenosological conditions of the body and carrying out timely preventive work in order to preserve the health of the population living in unfavorable climatic and geographical conditions.

For this purpose, within the framework of this study, a comprehensive analysis of the mechanisms underlying the life support of the organism under the long-term influence of the conditions of the North, and, in particular, adaptation to

9 loda. The role of mechanisms providing stable adaptation to cold has been established, namely, the importance of cold-induced vascular reactions and the functional state of the motor system on the basis of modern electroneuromyographic methods.

Purpose of the study

To establish the significance of the mechanisms of temperature adaptation in the formation of human health in the North, as well as to study the mechanisms of the development of maladjustment to cold and their manifestations in order to diagnose pre-zological conditions of a person in the North.

Research objectives

To investigate the adequacy of the cold adaptation process based on the analysis of the frequency of cold-associated symptoms.

To assess the functional state of the autonomic nervous system and the parameters of pulmonary ventilation, depending on the degree of adaptation of subjects to the conditions of the European North.

To investigate the conductive properties of sensory and motor fibers of peripheral nerves in groups with different adaptability to the conditions of the European North.

To establish the turn-amplitude characteristics of IEMG of isometric contraction, characterizing the "neurogenic" type of skeletal muscle dysfunctions.

To establish the ontogenetic features of the motor system on the basis of turn-amplitude analysis of IEMG during dosed isometric contraction, as well as during a functional test with muscle fatigue.

Establish electroneuromyographic signs characterizing the performance and functional state of the motor system

10 with the combined influence of cold and harmful production factors (industrial vibration).

Scientific novelty

The study for the first time carried out a systematic analysis of the state of the human body in the North and showed the role of the mechanisms underlying temperature adaptation in the formation of human health in the North, as well as the prerequisites for the development of maladjustment to cold and the occurrence of prenosological conditions.

For the first time, the role of cold-associated symptoms as signs of maladjustment of the body to cold conditions was studied and the relationship between their occurrence and the state of the functional system of temperature adaptation was shown. It was found that the subjective signs of maladjustment to cold in the form of HAS correlate with “pre-pathological” changes in autonomic regulation, functioning of the cardiovascular system, the state of pulmonary ventilation and electrophysiological properties of the motor system.

With the help of modern electrophysiological methods, quantitative characteristics of the functional state and reserves of the human motor system are given under conditions of prolonged exposure to cold as a manifestation of the plasticity of the motor system. In addition, for the first time, on the basis of the quantitative parameters of IEMG, the features of the structural and functional state of the peripheral part of the motor system in different periods of ontogenesis were established. The interaction of mechanisms of long-term adaptation to cold and individual factors at the level of skeletal muscles is shown.

With the help of complex electroneuromyographic methods, for the first time, a negative effect of adaptation to cold was revealed in the form of impaired myelination in the peripheral nervous system and its potential role in reducing the performance of the motor system in individuals was shown.

11 living for a long time in the conditions of the North, as well as in the development and progression of diseases of the motor system with prolonged exposure to cooling.

Theoretical and scientific-practical significance

The study develops the provisions of adaptive medicine in the study of factors affecting human health in the North, and the general patterns of the development of maladaptive reactions. Within the framework of this study, a systematic analysis of the state of human health in the North from the point of view of the adequacy of the process of long-term adaptation to cold has been carried out. The importance of cold-associated symptoms is shown as signs of inadequacy of the process of long-term adaptation to cold and risk factors for the development of pathology in various body systems in the North.

The subjective signs of maladjustment to cold in the form of HAS and the results of a complex functional study were compared. In particular, using the methods of functional diagnostics, signs were established that indicate maladjustment to cold: increased participation of adrenergic mechanisms of regulation of functions in migrants compared to permanent residents of the North, as well as in people with cold-associated symptoms in the form of Raynaud's phenomenon; subclinical ventilation disorders were found in migrants compared with permanent residents of the North, as well as in people with cold-associated symptoms in the form of cold shortness of breath.

The negative effect of adaptation to cold in the form of a decrease in neuromuscular innervation was proved and the features of the electroneuro-myographic characteristics of the motor system were established depending on the adaptation to cold, with a combination of environmental conditions of prolonged cooling and age-related changes, as well as harmful production factors (industrial vibration).

Analysis of the interaction of the functional state of the motor system (mechanisms of long-term adaptation to cold) and vegetative support of body functions (factors of urgent adaptation to cold, compensatory mechanisms) is of theoretical importance for studying the hierarchy and interaction of different body functions, and can find its application in systems theory.

The scientific and practical significance of the dissertation lies in the improvement of the EMG technique in terms of the development of non-invasive methods of signal registration and quantitative (turn-amplitude) IEMG analysis. The results of the used method of turn-amplitude analysis of IEMG with dosed isometric contraction and the widely used method of stimulation ENMG are compared. The use of IEMG quantitative analysis has been expanded to assess the performance and functional reserves of the human motor system in various functional states, including those associated with the long-term influence of the North.

With the help of the complex application of electroneuromyographic research methods, including turn-amplitude analysis of IEMG, electromyographic syndromes characterizing age-related changes in the motor system in residents of the North, conditions associated with muscle overstrain during fatigue and recovery, as well as in pathology of the motor system due to prolonged influence industrial vibration.

The significance of cold-associated symptoms as early signs of maladjustment to cold and the development of prenosological conditions in the North is shown.

Provisions for Defense:

Cold-associated symptoms characterize the state of "pre-disease" associated with inadequate provision of the process of long-term adaptation to cold; increased cold-induced vasoconstriction is a sign of increased participation of adrenergic mechanisms of regulation of body functions and intense adaptation to cold.

The negative effect of adaptation to cold, which forms in the human motor system, is characterized by a decrease in the functional capabilities of skeletal muscles due to a violation of the conductive properties of peripheral nerves.

The "neurogenic" type of IEMG that forms with age is due to the potentiating influence of environmental factors, in particular, cooling conditions, which contributes to the age-related decrease in the function of the motor system in permanent residents of the North, and also serves as a factor predisposing to the development and progression of pathology of the musculoskeletal system in the regions with a cold climate.

Approbation of work

The main results of the dissertation were reported and discussed at Russian and international scientific symposia: III International Congress on Pathophysiology (Lahti, 1998); II and III Russian Congress on Pathophysiology (Moscow, 2000, 2004); XXXIII International Congress of Physiological Sciences (St. Petersburg, 1997); VIII World Congress of the Society for Adaptive Medicine (Moscow, 2006); at the joint Plenums of the Russian and Moscow Scientific Societies on Pathophysiology (Moscow, 2006, 2007); XVII World Congress on Neurology (London, 2001), XVIII and XIX congresses of the Volga Federal District. I.P. Pavlova (Kazan, 2001; Ekaterin-

14 Burg, 2004), IV and V congresses of physiologists of Siberia and the Far East (Novosibirsk, 2002; Tomsk, 2004); All-Russian Forum "The health of the nation is the basis of Russia's prosperity" (Moscow, 2005); XI National Congress “Man and His Health” (St. Petersburg, 2006); international conferences Environmental Ergonomics (Aahen, 2000), Problems with Cold Work (Solna, 1998); symposium "Pathophysiology and modern medicine" (Moscow, 2004); conferences "Mechanisms of typical pathological processes" (St. Petersburg, 2003), II, III, IV international conferences on physiology of muscles and muscle activity (Moscow, 2003, 2005, 2007), I All-Russian conference with international participation "Motion control" (Great Luke, 2006); the Russian conference "Organism and the Environment: Human Life Support and Protection in Extreme Conditions" (Moscow, 2000); international conference "Problems of Human Ecology" (Arkhangelsk, 2000, 2004); 10th All-Russian Conference on Labor Physiology (Moscow, 2001); Russian conference " Actual problems ecological human physiology in the North ”(Syktyvkar, 2001, 2004); XI International Symposium "Ecological and Physiological Problems of Adaptation" (Moscow, 2003); 6th scientific-practical conference "Methods of research of regional blood circulation and microcirculation in the clinic and experiment" (St. Petersburg, 2007).

Implementation of research results

The dissertation work was carried out within the framework of targeted research programs (state registration No. 0120.0603111 (Study of the basic mechanisms of thermoregulatory muscle activity in building movement and motor control in humans), 0120.0502699 (Study of neurophysiological mechanisms of human movement under the action of factors limiting the functional capabilities of the motor system)) ... This research was supported by grants from the Russian Foundation for Basic Research 307-2003-04, the Russian State Scientific Foundation "Russian

15 Sever "01-06-49004 a / s, by the Program of the Federal Education" Universities of Russia "UR 11.01.245.

The theoretical provisions of the dissertation are included in the curricula in the disciplines "Pathophysiology" and "Normal Physiology" at the Faculty of Medicine of PetrSU, the author has developed and implemented educational process electronic educational resource "Stress and Adaptation" (act of implementation of 10.10.07). The results of the work are used in the therapeutic and diagnostic practice of the Republican Hospital, the Children's Republican Hospital (Republic of Karelia, Petrozavodsk).

Personal contribution

The setting of research goals and objectives, planning and conducting research, analyzing and summarizing data, preparing publications based on the dissertation materials were carried out by the author personally, in joint research - with his decisive role.

Publications

Volume and structure of the thesis

The text of the thesis is presented on 289 pages, consists of an introduction, a review of literature, materials and research methods, the results of one's own research, a discussion of the results, conclusions, conclusions, practical recommendations and bibliography. The list of literature includes 430 sources, including 185 - domestic and 245 - foreign. The thesis contains 28 tables and 48 figures.

The concept of health in the aspect of adaptation theory

Currently, the problem of the interaction of the human body with the environment does not lose its relevance. A complex set of external influences, including a wide range of anthropogenic influences, makes high demands on the body. The preservation of human health, the prevention of diseases is becoming not only a particular problem of medicine, but also of natural science in general, as well as one of the general humanitarian values.

The adaptation of the structure and functions of the body to environmental conditions occurs in the process of adaptation. According to G. Selye's concept, adaptation is one of the fundamental qualities of living matter, which is often identified with the very concept of life. In the modern understanding, adaptation is the process of forming optimal structural and functional conformity, which ensures the most beneficial functioning of the body in certain conditions. In this case, the problem of the interaction of the organism with the environment is considered within the framework of the system-functional approach, which takes into account not only external connections, but also a set of changes within the organism, aimed at maintaining homeostasis.

In this regard, the main content of adaptation is internal processes in systems that ensure the preservation of its external functions in relation to the environment. This goal is achieved through adaptive and compensatory responses. Adaptive reactions consist in the fact that the system, responding to changes in the parameters of the environment that are essential for it, rebuilds its structural connections in order to preserve the functions that ensure its existence as a whole. Compensatory reactions are aimed at preserving the function of the system even in the event of a violation of the activity of a functional element. Thus, compensatory reactions are carried out not by the element, but by the system in relation to the element.

Adaptation is used in various ways. There is a genotypical adaptation - a process that forms the basis of evolution, in which, due to hereditary variability, mutations and natural selection modern species of animals and plants were formed. The complex of specific hereditary traits underlies another type of adaptation acquired in the course of the individual development of the organism - phenotypic adaptation, which forms the individual appearance of the organism.

The concept of phenotypic adaptation was formulated by F. Z. Meerson. According to this theory, two stages can be traced in the development of most adaptive reactions: the initial stage is an urgent but imperfect adaptation and the next stage is a perfect, long-term adaptation.

An urgent adaptation reaction occurs immediately after the onset of the stimulus. Most important in maintaining homeostasis at early stages adaptations have compensatory reactions of the organism. Reflex reactions arising under the action of hypoxia, cold, heat, etc. are typical manifestations of the urgent stage of adaptation. ... An important place in the initial period of adaptation is occupied by nonspecific mechanisms for increasing the resistance of the organism, i.e., the stress reaction.

Long-term adaptation develops gradually, as a result of repeated or prolonged action of environmental factors, on the basis of repeated implementation of urgent adaptation. The basis of long-term adaptation is formed by structural changes in organs and systems that are most involved in the compensatory reactions of the urgent stage. Studies carried out on a variety of objects have unequivocally shown that an increase in the function of organs and systems naturally entails the activation of the synthesis of nucleic acids and proteins in the cells that form these organs and systems. This leads to a complex of structural changes that fundamentally increase the capacity of systems responsible for adaptation, which forms the basis for the transition from an urgent stage of adaptation to a long-term one.

According to F. 3. Meerson, the founder of the direction of "adaptation medicine", phenotypic adaptation in humans is more important than in other animal species, since in humans this process is more meaningful and effective. In accordance with these ideas, R.P. Kaznacheev defined adaptation (adaptation) as the process of maintaining the functional state of homeostatic systems and the body as a whole, ensuring its preservation, development, performance, maximum life expectancy in inadequate environmental conditions. Ecological conditions are considered inadequate if they do not correspond at the moment to the genophenotypic properties of the organism as a biosystem. The use of adaptation of the organism to various environmental factors makes it possible to expand the zone of human existence and allows you to maintain health in adverse conditions.

Research conditions, control of the thermal state of the subjects

Before conducting the study, each subject was familiarized with the protocol of the electromyographic study and the nature of the temperature effect. The comparison group consisted of volunteer subjects, practically healthy at the time of the study, in the presence of chronic diseases without exacerbation. The selection of subjects was carried out on the basis of anamnesis data and a standard examination immediately before the electromyography session (measurement of temperature, blood pressure). The study of children was carried out with the consent of the parents in the presence of medical personnel. The subjects could voluntarily discontinue participation in the study at any time.

Electroneuromyographic studies, analysis of the evoked cutaneous vegetative potential (ECVP) and spirometric tests were carried out in the laboratory (air temperature +22 - 24C, humidity 50-60%; air velocity less than 0.1 m / s) after a 30-minute stay of the subject in the room for stabilization skin temperature.

To control the thermal state of the subjects, the central temperature (TC) was measured sublingually or rectally and the weighted average temperature of the skin (SVTK) according to N. L. Ramanathan. To do this, the temperature of the track was measured at 4 points - under the clavicle (Ti), on the lateral surface of the middle of the shoulder (Tg), on the lateral surface of the middle of the thigh (T3) and on the medial surface of the middle of the leg (T4). Further calculation of the SVTC was carried out according to the formula: SVTC = 0.3 (T, + T2) + 0.2 (T3 + T4), where the coefficient in front of the temperature values ​​means the approximate surface area of ​​these skin areas. SVTC was determined every 5 to 10 minutes. Figure 2.1 shows the graphs of SVTC registration during electroneuromyographic studies in adult subjects. The central temperature was measured sublingually, since it accurately reflects its changes and is easy to practical application.

In children aged 7 days to 3 years, the skin temperature was measured only at one point (on the thigh), since, firstly, it accurately reflects changes in the SVTC and, secondly, the abundance of electrodes (electromyographic and temperature) caused significant emotional - motor restlessness of the child, which would inevitably affect the nature of the EMG.

Temperature sensors based on copper-constantan thermocouples were used to measure the temperature. Changes in the electrical properties of the thermocouple were converted to digital values ​​using a 5-channel indicator.

The strength of the maximal voluntary contraction (MVC) of the biceps brachii (ga. Biceps brachii) was determined as follows. The subject was standing, his arm was in the position of elbow flexion (the shoulder is located along the chest, the articular angle is 90). The subject in this position had to exert maximum pressure on the dynamometer, mounted on the lower surface of the stationary one. Dynamometry was performed before each EMG session.

The MVC of the forearm muscles was determined with brush pressure on a dynamometer mounted on the lower surface of a fixed beam. In this case, the elbow joint was fixed in the splint to avoid the involvement of the shoulder muscles.

Dosing of static force (isometric contraction) of t. Biceps brachii was created with weights weighing 4, 6, 8, and 10 kg, suspended on a cuff attached to the forearm, 2 - 3 cm proximal to the wrist joint, for 3 - 5 s. The subjects in the standing position were asked to hold the arm in the position of elbow flexion (the shoulder is located along the thorax, the articular angle is 90).

The fatigue of T. biceps brachii was caused by dynamic loading to failure. A standing test subject had to perform flexion-extension movements in the elbow joint with a load equal to 30% of the MVC, until the inability to perform full-fledged movements using solely the arm muscles or until the onset of pain.

Dosing of the static force of the forearm muscles (i.e. flexor carpi radialis, i.e. flexor carpi radialis) was created with weights weighing 4, 6, 8, and 10 kg suspended on a cuff attached to the hand for 3 - 5 s. The subjects in the sitting position were asked to maintain the loaded hand at the same level with the forearm, while the arm was in the position of elbow flexion, the elbow joint was fixed on the armrest. Fatigue of the forearm muscles was caused by flexion-extension movements in the wrist joint with a load equal to 30% of the MVC.

Functional indicators of the external respiration system in individuals with different adaptability to the conditions of the European North

Parameters characterizing lung volumes and airway patency, depending on gender and adaptation to the conditions of the European North, are presented in Table 4.1. According to functional studies of the external respiration system, mild ventilation disorders were documented in 9 people (30%).

The study of the function of external respiration revealed a tendency towards the formation of impaired pulmonary ventilation in migrants (see Table 4.1, Fig. 4.2, 4.3). Thus, VC (% of the due value) in the group of men permanently residing in the North-West region of the Russian Federation (NW - m) was 96.96 ± 8.54, in the group of women permanently residing in the North-West region of the Russian Federation (NW - g), - 98.81 ± 16.27, in the group of men who arrived from other regions (South - m), -76.43 ± 13.98 (p 0.05 compared to NW), in the group of women, those who arrived from other regions (South - w) - 95.13 ± 13.10 (p 0.05 compared to m); inspiratory volume (l) in the SZ - m group was 3.60 ± 0.35, SZ - w - 2.60 ± 0.34 (p 0.001 compared to m), South - m - 2.83 ± 0.11 (p 0.001 compared to NW), South - w - 2.28 ± 0.36 (p 0.05 compared to South - m).

Thus, analysis of lung volumes revealed restrictive ventilation disorders in male migrants.

Studies of the parameters of forced expiration revealed obstructive ventilation disorders, also more characteristic of male migrants. So, FVC (% of the due value) in the NW - m group was 81.64 ± 14.89, NW - w - 84.05 ± 12.06, South - m - 71.43 ± 15.29, South - w - 67.20 ± 9.72; FEV0.5 (l) in the SZ - m group was 3.33 ± 0.31, SZ - w - 2.26 ± 0.47 (p 0.001 compared to m), South - m - 2.58 ± 0, 16 (p 0.01 compared to NW), South - w - 2.03 ± 0.44 (p 0.05 compared to m); Tiffno's test, calculated as the ratio of FEV / FVC, in the group CZ - m was 99.10 ± 1.40, CZ - w - 96.41 ± 3.63, South - m - 96.47 ± 3.29, South - g - 99.18 ± 1.28; peak volumetric velocity during expiration (POS,% of the due value) in the CZ - m group was 110.19 ± 6.60, CZ - w - 90.14 ± 25.85, South - m - 74.03 ± 6, 83 (p 0.01 compared to NW), South - w - 89.48 ± 30.15; SOS25-75 (average volumetric expiratory flow rate, determined during expiration from 25 to 75% of FVC), characterizing the patency of small and medium bronchioles, in the C3 - m group was 131.71 ± 18.66, C3 - g - 109.43 ± 26.06, South-m - 88.73 ± 9.00 (p 0.01 compared to NW), South-f - 110.30 ± 26.18.

In persons with shortness of breath in the cold, a significant decrease in pulmonary ventilation indicators was revealed (Fig. 4.4). Thus, the volume of inspiration was the smallest in migrants from the south with this symptom (p 0.001), in the same group indicators characterizing airway patency (FVC in% of the required value, FEVo, 5 (l) and FEV] in% of the due values) were also lower in comparison with the indicators for permanent residents of the NW and persons without shortness of breath (p 0.05).

With a high sensitivity to cold in the form of enhanced cold-induced vasoconstriction (Raynaud's phenomenon), significant changes in the parameters of pulmonary ventilation were observed, which indicates the participation of microcirculation disorders in the pathogenesis of respiratory disorders. Correlations showing the relationship between risk factors and parameters characterizing ventilation are shown in Figure 4.5.

The indices of blood pressure and pulse did not differ significantly between the studied groups and averaged: ABP - 113.41 ± 3.01 mm Hg. Art., ADP - 67.00 ± 1.96 mm. rt. Art., heart rate - 77.64 ± 2.37 beats / min "1 (Table 4.2).

The level of adaptive capabilities, calculated on the basis of the IFI, in the studied group as a whole corresponded to the upper limit of normal values ​​(see Table 4.2). It was also noted that in the group of men the level of IFI was higher (p 0.05), which is on the borderline between satisfactory adaptation and the stress of adaptation mechanisms. lower than satisfactory ratings, with higher rates in men (Fig. 4.6).

A correlation was established between IFI and PDP with the presence of increased cold-induced vasoconstriction in the subjects (p 0.05). Individuals with signs of increased cold-induced vasoconstriction demonstrated IFI and RAP corresponding to the tension of adaptation mechanisms. Thus, in the group with this symptom, the IFI was 2.12 ± 0.07 (p 0.05 compared with the group without increased cold-induced vasoconstriction 1.86 ± 0.09); The MAP in the group with this symptom was 94.41 ± 4.37 (p 0.05 compared with the group without increased cold-induced vasoconstriction 79.85 ± 5.68). The highest IFI values ​​were observed in men with increased cold-induced vasoconstriction (2.21 ± 0.09, p 0.05).

Evaluation of neuromuscular status using turn-amplitude IEMG analysis

Determination of the neuromuscular status based on the analysis of turn-amplitude parameters of EMG was carried out in patients with diphtheria lesions of the peripheral nervous system. Diagnosis of diphtheria lesions of the nervous system was based on the data established by the clinical study of patients, the results of bacteriological and serological methods, as well as the results of additional methods that allow to clarify the severity and localization of lesions of the nervous system. Research carried out jointly with A.M.Sergeev

Electroneuromyography (ENMG) was performed in 17 patients (6 m, 11 f) aged 18 to 61 years (mean age 35.9 ± 3.3 years) 1 to 18 months after a diphtheria infection, accompanied by the development of polyneuropathy.

The diagnosis of diphtheria in 15 cases was confirmed bacteriologically in the acute period of the disease, and in 2 patients it was made retrospectively on the basis of anamnesis, typical clinic, unfavorable epidemiological situation. In the examined group of patients, symptoms of generalized sensory-motor polyneuropathy appeared after 9 - 45 days (on average, after 26 ± 3 days) from the onset of the main infectious disease, in 6 people the disease proceeded in the form of polyradiculoneuropathy according to the Guillain-Barré syndrome type.

At the time of the study, on the basis of a clinical assessment of the function of the peripheral nervous system, the patients were divided into 2 groups. The first group consisted of 6 patients (2 m., 4 f.) Aged 18 - 46 years, examined 10 - 18 months after the diphtheria. In this group of patients, no motor dysfunction was found during clinical examination. However, distal-type sensory disorders have been identified. The second group included 11 patients (4 m., 7 f.) Aged 30 - 56 years, who were examined 4 - 9 months after the onset of the main infectious disease. At the time of examination, these patients showed signs of impaired motor function in the form of moderately expressed flaccid tetraparesis (n = 6) or minimal muscle weakness in the distal extremities, mainly in the flexors of the hand (n = 5). This corresponds to the I-II degree of motor deficit on the North American scale.

The control group consisted of 7 neurologically healthy volunteer subjects (4 m, H) aged 18 to 39 years (mean age 28.5 ± 2.4 years). Characteristics of the electroneuromyogram in healthy subjects The speed of propagation of excitation (SRV) along the motor fibers of the ulnar nerve in healthy individuals was 60 - 70 m / s (on average 66.42 ± 2.87 m / s).

In healthy subjects, 41 motor unit potentials (MUU), i.e., triceps brachii, were recorded using cutaneous electrodes. MUAPs in healthy individuals were characterized by a duration of 24 - 30 ms, an amplitude not exceeding 250 µV (mainly 90–150 µV), and the number of phases, as a rule, less than 3x. The number of pseudo-polyphase PDEs was less than 10%. The average characteristics of the MUAP are presented in Table 6.1.

Investigation of the characteristics of the interference IEMG in healthy subjects revealed a regular increase in the amplitude (RMS) and the number of EMG “turns” (turns) of T. flexor carpi radialis with increasing load (Table 6.2).

In a two-dimensional coordinate system, where the abscissa axis reflects the values ​​of the applied load in kg, and the ordinate axis reflects the corresponding values ​​of the EMG parameters, the dependence of the IEMG parameters from the flexor carpi radialis on the load was expressed by linear equations.

Regression coefficients reflecting the increase in EMG parameters and showing the slopes of the graphs to the x-axis did not practically differ in individual subjects. The values ​​of the regression coefficients were in the range of 12.9-15.5 for the IEMG amplitude, for the number of EMG turns they were 12.0-14.5 (Table 6.3, Fig. 6.1). Attention is drawn to the almost fourfold increase in both the amplitude characteristics (RMS, Fig. 6.1, A) and the number of turns (Fig. 6.1, B) with an increase in the load from 2 to 8 kg.

Analysis of the IEMG parameters without taking into account the load by studying the ratio of the number of EMG turns to the average EMG amplitude in 1 s (Willison's method) revealed that the maximum value of this ratio for flexor carpi radialis is observed in the amplitude range from 200 to 260 μV, for gastrocnemius - from 190 to 240 μV, averaging 0.4 - 0.5 and 0.6 - 0.7, respectively (Table 6.4, Fig. 6.2).

Terentyeva Nadezhda Nikolaevna

In the previous chapter, general (i.e., non-specific) laws of adaptation were analyzed, but the human body responds in relation to specific factors and specific adaptive reactions. It is these reactions of adaptation (to a change in temperature, to a different regime of motor activity, to weightlessness, to hypoxia, to a lack of information, to psychogenic factors, as well as the peculiarities of human adaptation and management of adaptation) are considered in this chapter.

ADAPTATION TO CHANGE IN TEMPERATURE

The temperature of the human body, like that of any homeothermic organism, is characterized by constancy and fluctuates within extremely narrow limits. These limits range from 36.4 ° C to 37.5 ° C.

Low temperature adaptation

The conditions under which the human body must adapt to cold can vary. This can be work in cold workshops (the cold does not work around the clock, but alternating with the normal temperature regime) or adaptation to life in northern latitudes (a person in the conditions of the North is exposed not only to low temperatures, but also to a changed illumination regime and radiation level).

Work in cold shops. The first days, in response to low temperatures, heat production grows uneconomically, excessively, heat transfer is still not sufficiently limited. After the establishment of the phase of stable adaptation, the processes of heat production are intensified, heat transfer is reduced; ultimately, an optimal balance is established to maintain a stable body temperature.

Adaptation to the conditions of the North is characterized by an unbalanced combination of heat production and heat transfer. A decrease in heat transfer efficiency is achieved due to a decrease in

and cessation of sweating, narrowing of the arterial vessels of the skin and muscles. Heat production is initially activated by increasing blood flow in internal organs and increasing muscle contractile thermogenesis. Emergency stage. An obligatory component of the adaptive process is the inclusion of a stress reaction (activation of the central nervous system, an increase in the electrical activity of thermoregulatory centers, an increase in the secretion of liberins in the neurons of the hypothalamus, in the pituitary adenocytes - adrenocorticotropic and thyroid-stimulating hormones, in the thyroid gland - thyroid hormones, in the brain substance of the supra-colorectal and in their cortex - corticosteroids). These changes significantly modify the function of organs and physiological systems of the body, changes in which are aimed at increasing the oxygen transport function (Fig. 3-1).

Rice. 3-1.Providing oxygen transport function during adaptation to cold

Persistent adaptation accompanied by increased lipid metabolism. In the blood, the content of fatty acids rises and the level of sugar decreases slightly, and fatty acids are washed out from the adipose tissue due to the enhancement of the "deep" blood flow. In mitochondria, adapted to the conditions of the North, there is a tendency to uncouple phosphorylation and oxidation, and oxidation becomes dominant. Moreover, there are relatively many free radicals in the tissues of the inhabitants of the North.

Cold water.The physical agent through which low temperatures affect the body is most often air, but also water. For example, when in cold water, the body is cooled faster than in air (water has 4 times higher heat capacity and 25 times higher thermal conductivity than air). So, in water, the temperature of which is + 12 ° C, heat is lost 15 times more than in air at the same temperature.

Only at a water temperature of + 33-35? C, the temperature sensations of people in it are considered comfortable and the time spent in it is not limited.

At a water temperature of + 29.4 ° C, people can stay in it for more than a day, but at a water temperature of + 23.8 ° C, this time is 8 hours and 20 minutes.

In water with a temperature below + 20? C, acute cooling phenomena develop rapidly, and the time of a safe stay in it is calculated in minutes.

A person's stay in water, the temperature of which is + 10-12? C, for 1 hour or less, causes life-threatening conditions.

Staying in water at a temperature of + 1 ° C will inevitably lead to death, and at + 2–5 ° C it causes life-threatening complications within 10-15 minutes.

The safe stay in ice water is no more than 30 minutes, and in some cases people die in 5-10 minutes.

The body of a person immersed in water experiences significant overloads due to the need to maintain a constant temperature of the "core of the body" due to the high thermal conductivity of water and the absence of auxiliary mechanisms that ensure thermal insulation of a person in the air layer of heated air near the skin). In cold water, a person has only two mechanisms for maintaining a constant temperature of the "core of the body", namely: increasing the production of heat and limiting the flow of heat from the internal organs to the skin.

Limiting the flow of heat from the internal organs to the skin (and from the skin to the environment) is provided by peripheral vasoconstriction, which is most pronounced at the level of the skin, and intramuscular vasodilation, the degree of which depends on the localization of cooling. These vasomotor reactions, redistributing the volume of blood towards the central organs, are able to maintain the temperature of the “core of the body”. Simultaneously with this, there is a decrease in plasma volume due to an increase in capillary permeability, glomerular filtration and a decrease in tubular reabsorption.

The increase in heat production (chemical thermogenesis) occurs through increased muscle activity, which is manifested by tremors. At a water temperature of + 25 ° C, shivering occurs when the skin temperature drops to + 28 ° C. In the development of this mechanism, three successive phases are distinguished:

Initial decrease in core temperature;

Its sharp increase, sometimes exceeding the temperature of the "body core" before cooling;

Decrease to a level depending on the water temperature. In very cold water (below + 10 ° C), the tremor begins very abruptly, is very intense, combined with rapid shallow breathing and a feeling of chest compression.

The activation of chemical thermogenesis does not prevent cooling, but is regarded as an “emergency” way of protecting against cold. A drop in the temperature of the "core" of the human body below + 35? C indicates that the compensatory mechanisms of thermoregulation cannot cope with the destructive effect of low temperatures, and deep hypothermia of the body sets in. The resulting hypothermia changes all the most important vital functions of the body, as it slows down the rate of flow chemical reactions in cages. An inevitable factor accompanying hypothermia is hypoxia. The result of hypoxia is functional and structural disorders, which in the absence of the necessary treatment lead to death.

Hypoxia has a complex and diverse origin.

Circulatory hypoxia occurs due to bradycardia and peripheral circulatory disorders.

Hemodynamic hypoxia develops due to the movement of the oxyhemoglobin dissociation curve to the left.

Hypoxic hypoxia occurs with inhibition of the respiratory center and convulsive contraction of the respiratory muscles.

High temperature adaptation

High temperatures can affect the human body in different situations (for example, at work, in case of fire, in combat and emergency conditions, in a bathhouse). Adaptation mechanisms are aimed at increasing heat transfer and reducing heat production. As a result, the body temperature (although it rises) remains within the upper limit of the normal range. The manifestations of hyperthermia are largely determined by the ambient temperature.

When the external temperature rises to + 30-31 ° C, the arteries of the skin expand and the blood flow in it increases, the temperature of the surface tissues increases. These changes are aimed at the return of excess heat by the body through convection, heat conduction and radiation, but as the ambient temperature rises, the efficiency of these heat transfer mechanisms decreases.

At an external temperature of + 32-33? C and above, convection and radiation cease. Heat transfer through perspiration and evaporation of moisture from the surface of the body and respiratory tract is of prime importance. So, with 1 ml of sweat, about 0.6 kcal of heat is lost.

In organs and functional systems during hyperthermia, characteristic shifts occur.

The sweat glands secrete kallikrein, which breaks down a, 2-globulin. This leads to the formation of kallidin, bradykinin and other kinins in the blood. Kinins, in turn, provide twofold effects: expansion of the arterioles of the skin and subcutaneous tissue; potentiation of perspiration. These effects of kinins significantly increase the body's heat transfer.

In connection with the activation of the sympathoadrenal system, the heart rate and cardiac output increase.

There is a redistribution of blood flow with the development of its centralization.

There is a tendency to an increase in blood pressure.

In the future, the adaptation is due to a decrease in heat production and the formation of a persistent redistribution of blood vessels. Excessive sweating becomes adequate at high temperatures. Loss of water and salt through sweat can be compensated for by drinking salted water.

ADAPTATION TO THE REGIME OF MOTOR ACTIVITY

Often, under the influence of any requirements of the external environment, the level of motor activity changes in the direction of its increase or decrease.

Increased activity

If physical activity becomes high as necessary, then the human body must adapt to a new

condition (for example, to severe physical work, sports, etc.). Distinguish between "urgent" and "long-term" adaptation to increased motor activity.

"Urgent" adaptation - the initial, emergency stage of adaptation - characterized by maximum mobilization of the functional system responsible for adaptation, pronounced stress response and motor arousal.

In response to the load, intense irradiation of excitation occurs in the cortical, subcortical and underlying motor centers, leading to a generalized but insufficiently coordinated motor response. For example, the heart rate increases, but there is also a generalized inclusion of "extra" muscles.

Excitation of the nervous system leads to the activation of stress-realizing systems: adrenergic, hypothalamic-pituitary-adrenocortical, which is accompanied by a significant release of catecholamines, corticoliberin, ACTH and somatotropic hormones. On the contrary, the concentration of insulin and C-peptide in the blood decreases under the influence of exertion.

Stress-implementing systems. Changes in hormone metabolism during stress reactions (especially catecholamines and corticosteroids) lead to the mobilization of the body's energy resources; potentiate the activity of the functional adaptation system and form the structural basis of long-term adaptation.

Stress limiting systems. Simultaneously with the activation of stress-realizing systems, there is an activation of stress-limiting systems - opioid peptides, serotonergic and others. For example, in parallel with an increase in blood ACTH content, an increase in blood concentration occurs. β -endorphin and enkephalins.

Neurohumoral restructuring during urgent adaptation to physical activity ensures the activation of the synthesis of nucleic acids and proteins, the selective growth of certain structures in the cells of organs, an increase in the power and efficiency of the activity of the functional adaptation system during repeated physical exertion.

With repeated physical exertion, muscle mass increases and its energy supply increases. Along with the

there are changes in the oxygen transport system and the efficiency of the functions of external respiration and myocardium:

The density of capillaries in skeletal muscles and myocardium increases;

The speed and amplitude of contraction of the respiratory muscles increase, the vital capacity of the lungs (VC), maximum ventilation, and the coefficient of oxygen utilization increase;

Myocardial hypertrophy occurs, the number and density of coronary capillaries increases, the concentration of myoglobin in the myocardium;

The number of mitochondria in the myocardium and the energy supply of the contractile function of the heart increase; the rate of contraction and relaxation of the heart during exercise increases, as well as stroke and minute volumes.

As a result, the volume of the function comes in line with the volume of the organ structure, and the body as a whole becomes adapted to the load of this magnitude.

Decreased activity

Hypokinesia (limitation of motor activity) causes a characteristic symptom complex of disorders that significantly limit a person's working capacity. The most typical manifestations of hypokinesia:

Violation of the regulation of blood circulation during orthostatic effects;

Deterioration of indicators of efficiency of work and regulation of the oxygen regime of the body at rest and during physical exertion;

Phenomena of relative dehydration, disorders of isoosmia, chemistry and tissue structure, impaired renal function;

Atrophy of muscle tissue, impaired tone and function of the neuromuscular apparatus;

Decrease in the volume of circulating blood, plasma and erythrocyte mass;

Violation of the motor and enzymatic functions of the digestive apparatus;

Violation of indicators of natural immunity.

Emergencythe phase of adaptation to hypokinesia is characterized by the mobilization of reactions that compensate for the lack of motor functions. Such defensive reactions include the excitement of sympathetic

adrenal system. The sympathoadrenal system causes temporary, partial compensation of circulatory disorders in the form of increased cardiac activity, increased vascular tone and, consequently, blood pressure, increased respiration (increased ventilation of the lungs). However, these reactions are short-lived and quickly fade away with continued hypokinesia.

The further development of hypokinesia can be imagined as follows:

Immobility contributes, first of all, to a decrease in catabolic processes;

The release of energy decreases, the intensity of oxidative reactions decreases;

In the blood, the content of carbon dioxide, lactic acid and other metabolic products decreases, which normally stimulate respiration and blood circulation.

Unlike adaptation to a changed gas composition, low ambient temperature, etc., adaptation to absolute hypokinesia cannot be considered complete. Instead of a resistance phase, there is a slow depletion of all functions.

ADAPTATION TO WEIGHTNESS

A person is born, grows and develops under the influence of gravity. The force of attraction forms the functions of skeletal musculature, gravitational reflexes, coordinated muscular work. With a change in gravity in the body, various changes are observed, determined by the elimination of hydrostatic pressure and redistribution of body fluids, elimination of gravitational-dependent deformation and mechanical stress of body structures, as well as a decrease in the functional load on the musculoskeletal system, elimination of support, and changes in the biomechanics of movements. As a result, hypogravitational motor syndrome is formed, which includes changes in sensory systems, motor control, muscle function, and hemodynamics.

Sensory systems:

Decrease in the level of support afferentation;

Decrease in the level of proprioceptive activity;

Changes in the function of the vestibular apparatus;

Changes in the afferent support of motor reactions;

Disorder of all forms of visual tracking;

Functional changes in the activity of the otolith apparatus with a change in the position of the head and the action of linear accelerations.

Motor control:

Sensory and motor ataxia;

Spinal hyperreflexia;

Change in motion control strategy;

Increasing the tone of the flexor muscles.

Muscles:

Decrease in speed-power properties;

Atony;

Atrophy, changes in the composition of muscle fibers.

Hemodynamic disorders:

Increased cardiac output;

Decreased secretion of vasopressin and renin;

Increased secretion of natriuretic factor;

Increased renal blood flow;

Decrease in blood plasma volume.

The possibility of true adaptation to weightlessness, in which a restructuring of the regulation system, adequate to the existence on Earth, occurs, is hypothetical and requires scientific confirmation.

ADAPTATION TO HYPOXIA

Hypoxia is a condition resulting from insufficient oxygen supply to tissues. Hypoxia is often combined with hypoxemia - a decrease in the level of tension and oxygen content in the blood. Distinguish between exogenous and endogenous hypoxia.

Exogenous types of hypoxia - normo- and hypobaric. The reason for their development: a decrease in the partial pressure of oxygen in the air entering the body.

Normobaric exogenous hypoxia is associated with a restriction of oxygen intake with air at normal barometric pressure. Such conditions develop when:

■ finding people in a small and / or poorly ventilated space (room, shaft, well, elevator);

■ violations of air regeneration and / or supply of oxygen mixture for breathing in aircraft and submersibles;

■ non-observance of the method of artificial ventilation of the lungs. - Hypobaric exogenous hypoxia can occur:

■ when climbing mountains;

■ for people raised to great heights in open aircraft, on lifting chairs, as well as when the pressure in the pressure chamber decreases;

■ with a sharp drop in barometric pressure.

Endogenous hypoxia is the result of pathological processes of various etiologies.

Distinguish between acute and chronic hypoxia.

Acute hypoxia occurs with a sharp decrease in oxygen access to the body: when the subject is placed in a pressure chamber, from where air is pumped out, poisoning with carbon monoxide, acute circulatory or respiratory failure.

Chronic hypoxia occurs after a long stay in the mountains or in any other conditions of insufficient oxygen supply.

Hypoxia is a universal acting factor to which effective adaptive mechanisms have been developed in the body over the course of many centuries of evolution. The body's response to hypoxic effects can be considered on the model of hypoxia when climbing mountains.

The first compensatory response to hypoxia is an increase in heart rate, stroke and minute blood volume. If the human body consumes at rest 300 ml of oxygen per minute, its content in the inhaled air (and, therefore, in the blood) has decreased by 1/3, it is enough to increase the minute blood volume by 30% so that the same amount of oxygen is delivered to the tissues ... The opening of additional capillaries in the tissues realizes an increase in blood flow, since this increases the rate of oxygen diffusion.

There is a slight increase in breathing intensity, shortness of breath occurs only with pronounced degrees of oxygen starvation (pO 2 in the inhaled air is less than 81 mm Hg). This is explained by the fact that increased respiration in a hypoxic atmosphere is accompanied by hypocapnia, which inhibits the increase in pulmonary ventilation, and only

after a certain time (1-2 weeks) of being in hypoxia, there is a significant increase in pulmonary ventilation due to an increase in the sensitivity of the respiratory center to carbon dioxide.

The number of erythrocytes and the concentration of hemoglobin in the blood increase due to the emptying of blood depots and blood thickening, and then due to the intensification of hematopoiesis. Decrease atmospheric pressure per 100 mm Hg causes an increase in the content of hemoglobin in the blood by 10%.

The oxygen-transporting properties of hemoglobin change, the shift of the oxyhemoglobin dissociation curve to the right increases, which contributes to a more complete release of oxygen to the tissues.

The number of mitochondria in cells increases, the content of respiratory chain enzymes increases, which makes it possible to intensify the processes of energy use in the cell.

Behavior modification occurs (limitation of physical activity, avoidance of exposure to high temperatures).

Thus, as a result of the action of all links of the neurohumoral system, structural and functional rearrangements occur in the body, as a result of which adaptive reactions to this extreme impact are formed.

PSYCHOGENIC FACTORS AND INFORMATION DEFICIT

Adaptation to the effects of psychogenic factors proceeds differently in individuals with different types of GNI (choleric, sanguine, phlegmatic, melancholic). In extreme types (choleric, melancholic), such adaptation is not persistent, sooner or later factors affecting the psyche lead to a breakdown of the GNI and the development of neuroses.

The main principles of anti-stress protection include the following:

Isolation from the stressor;

Activation of stress-limiting systems;

Suppression of the focus of increased excitation in the central nervous system by creating a new dominant (switching attention);

Suppression of the negative reinforcement system associated with negative emotions;

Activation of the positive reinforcement system;

Restoration of the body's energy resources;

Physiological relaxation.

Information stress

One of the types of psychological stress is information stress. The problem of information stress is a problem of the XXI century. If the flow of information exceeds the capabilities of the brain for processing it formed in the process of evolution, information stress develops. The consequences of information overloads are so great that even new terms are introduced to denote not entirely clear states of the human body: chronic fatigue syndrome, computer addiction, etc.

Adapting to a lack of information

The brain needs not only minimal rest, but also a certain amount of arousal (emotionally significant stimuli). G. Selye describes this state as a state of eustress. The consequences of a lack of information include a lack of emotionally significant stimuli and growing fear.

A deficiency of emotionally significant stimuli, especially at an early age (sensory deprivation), often leads to the formation of an aggressor's personality, and the significance of this factor in the formation of aggressiveness is an order of magnitude higher than physical punishment and other factors harmful in educational terms.

In conditions of sensory isolation, a person begins to experience increasing fear, up to panic and hallucinations. E. Fromm calls the presence of a sense of unity as one of the most important conditions for the maturation of an individual. E. Erickson believes that a person needs to identify himself with other people (reference group), nation, etc., that is, say "I am like them, they are the same as me." It is preferable for a person to identify himself, even with such subcultures as hippies or drug addicts, than not to identify himself at all.

Sensory deprivation (from lat. sensus- feeling, sensation and deprivatio- deprivation) - a prolonged, more or less complete deprivation of a person of visual, auditory, tactile or other sensations, mobility, communication, emotional experiences, carried out either for experimental purposes, or as a result

tate of the current situation. In sensory deprivation, in response to the lack of afferent information, processes are activated that in a certain way affect the figurative memory.

As the time spent in these conditions increases, people develop emotional lability with a shift towards low mood (lethargy, depression, apathy), which for a short time are replaced by euphoria and irritability.

Memory disorders are observed, which are in direct proportion to the cyclic nature of emotional states.

The rhythm of sleep and wakefulness is disturbed, hypnotic states develop, which are delayed for a relatively long time, are projected outward and are accompanied by the illusion of involuntariness.

Thus, restriction of movement and information are factors that violate the conditions for the development of the organism, leading to the degradation of the corresponding functions. Adaptation in relation to these factors is not of a compensatory nature, since it does not show the typical features of active adaptation and only reactions associated with a decrease in functions prevail and ultimately lead to pathology.

PECULIARITIES OF ADAPTATION IN HUMAN

The peculiarities of human adaptation include a combination of the development of physiological adaptive properties of an organism with artificial methods that transform the environment in its interests.

Adaptation management

Adaptation management methods can be divided into socio-economic and physiological.

The socio-economic methods include all measures aimed at improving living conditions, nutrition, creating a safe social environment. This group of activities is extremely important.

Physiological methods of managing adaptation are aimed at the formation of nonspecific resistance of the organism. These include the organization of the regime (change of sleep and wakefulness, rest and work), physical training, hardening.

Physical training. Most effective remedy increasing the body's resistance to diseases and adverse environmental influences are regular physical exercise... Physical activity affects many vital systems. It extends to the balance of metabolism, activates the autonomic systems: blood circulation, respiration.

Hardening. There are activities aimed at increasing the body's resistance, united by the concept of "hardening". A classic example of hardening is constant cold training, water procedures, outdoor exercises in any weather.

Dosed use of hypoxia, in particular in the form of a training stay of a person at an altitude of about 2-2.5 thousand meters, increases the body's nonspecific resistance. The hypoxic factor contributes to the increased release of oxygen to the tissues, its high utilization in oxidative processes, the activation of enzymatic tissue reactions, the economical use of the reserves of the cardiovascular and respiratory systems.

A stress reaction from the adaptation link can, under excessively strong environmental influences, transform into a pathogenesis link and induce the development of diseases - from ulcerative to severe cardiovascular and immune diseases.

QUESTIONS FOR SELF-CONTROL

1. What is the adaptation to the action of low temperature?

2. What are the differences in the adaptation to the action of cold water.

3. Name the mechanism of adaptation to the action of high temperature.

4. What is the adaptation to high physical activity?

5. What is the adaptation to low physical activity?

6. Is adaptation to weightlessness possible?

7. What is the difference between adaptation to acute hypoxia and adaptation to chronic hypoxia?

8. Why is sensory deprivation dangerous?

9. What are the features of human adaptation?

10. What ways of managing adaptation do you know?

I'll tell you about one of the most incredible, from the point of view of everyday ideas, practices - the practice of free adaptation to the cold.

According to generally accepted ideas, a person cannot be in the cold without warm clothes. The cold is absolutely destructive, and as fate willed to go out into the street without a jacket, the unfortunate person is waiting for a painful freezing, and an inevitable bouquet of illnesses upon his return.

In other words, generally accepted concepts completely deny a person the ability to adapt to the cold. The comfort range is considered to be located exclusively above room temperature.

It seems that you can not argue. You can't spend the whole winter in Russia in shorts and a T-shirt ...

The fact of the matter is that you can !!

No, without clenching your teeth, overgrown with icicles to set a ridiculous record. And free. Feeling, on average, even more comfortable than others. This is a real hands-on experience that breaks conventional wisdom in a crushing way.

It would seem, why own such practices? Everything is very simple. New horizons always make life more interesting. Removing the instilled fears, you become freer.
The comfort range is expanding enormously. When the rest is hot, sometimes cold, you feel good everywhere. Phobias disappear completely. Instead of fear of getting sick, if you don't dress warmly enough, you get complete freedom and confidence in your abilities. Running in the cold is really nice. If you go beyond your powers, then this does not entail any consequences.

How is this even possible? Everything is very simple. We are much better organized than is commonly believed. And we have mechanisms that allow us to be free in the cold.

First, when the temperature fluctuates within certain limits, the metabolic rate, the properties of the skin, etc. change. In order not to dissipate heat, the outer contour of the body greatly lowers the temperature, while the core temperature remains very stable. (Yes, cold paws are normal !! No matter how we were convinced in childhood, this is not a sign of freezing!)

With an even greater cold load, specific mechanisms of thermogenesis are activated. We know about contractile thermogenesis, in other words, tremors. The mechanism is, in fact, an emergency. The shiver warms, but it turns on not from a good life, but when you really freeze.

But there is also non-contractile thermogenesis, which produces heat through the direct oxidation of nutrients in the mitochondria directly into heat. In the circle of people practicing cold practices, this mechanism was called simply "stove". When the "stove" is turned on, heat is regularly produced in the background in an amount sufficient for a long stay in the frost without clothes.

Subjectively, this feels rather unusual. In Russian, the word "cold" refers to two fundamentally different sensations: "cold outside" and "cold for you." They can be present independently. You can get cold in a warm enough room. And you can feel a burning cold outside on your skin, but do not freeze at all and not experience discomfort. Moreover, it is pleasant.

How does one learn to use these mechanisms? I will emphatically say that I consider "learning by article" risky. The technology must be handed over personally.

Non-contractile thermogenesis starts in a fairly severe frost. And its inclusion is quite inertial. The “stove” does not start working earlier than in a few minutes. Therefore, paradoxically, learning to walk freely in the cold is much easier in severe frost than on a cool autumn day.

As soon as you go out into the cold, you begin to feel the cold. At the same time, an inexperienced person is seized with panic horror. It seems to him that if it is already cold now, then in ten minutes a full paragraph will come. Many simply do not wait for the "reactor" to reach operating mode.

When the “stove” starts, it becomes clear that, contrary to expectations, it is quite comfortable to be in the cold. This experience is useful in that it immediately breaks the patterns inspired from childhood about the impossibility of such a thing, and helps to look differently at reality as a whole.

For the first time, you need to go out into the cold under the guidance of a person who already knows how to do it, or where you can return to the warmth at any time!

And you need to go out extremely naked. Shorts, even better without a shirt and nothing else. The body needs to be properly scared so that it turns on forgotten adaptation systems. If you get scared and put on a sweater, trowel, or something like that, then the heat loss will be enough to freeze very much, but the "reactor" will not start!

For the same reason, gradual "hardening" is dangerous. A decrease in the temperature of the air or bath "by one degree in ten days" leads to the fact that sooner or later the moment comes when it is already cold enough to get sick, but not enough to trigger thermogenesis. Truly, only iron people can withstand such hardening. But almost everyone can go straight out into the cold or dive into an ice-hole.

After what has been said, one can already guess that adaptation not to frost, but to low above-zero temperatures is a more difficult task than jogging in frost, and it requires higher preparation. The "stove" at +10 does not turn on at all, and only nonspecific mechanisms work.

It should be remembered that severe discomfort cannot be tolerated. When everything works out correctly, no hypothermia develops. If you start to get very cold, then you need to interrupt the practice. Periodic going beyond the limits of comfort is inevitable (otherwise it will not be possible to push these limits), but the extreme should not be allowed to grow into a kick-ass.

The heating system gets tired of working under load over time. The limits of endurance are very far. But they are. You can walk freely at -10 all day, and at -20 for a couple of hours. But you won't be able to go on a ski trip in one T-shirt. (Field conditions are a separate topic altogether. weather. But, with experience)

For greater comfort, it is better to walk like this in more or less clean air, away from the sources of smoke and from smog - the sensitivity to what we breathe in this state increases significantly. It is clear that practice is generally incompatible with smoking and booze.

Being in the cold can cause cold euphoria. The feeling is pleasant, but requires extreme self-control in order to avoid loss of adequacy. This is one of the reasons why it is highly undesirable to start the practice without a teacher.

Another important nuance is a prolonged reboot of the heating system after significant loads. Having picked up the cold properly, you can feel pretty good, but when you enter a warm room, the "stove" turns off, and the body begins to warm up with tremors. If, at the same time, you go out into the cold again, the "stove" will not turn on, and you can get very cold.

Finally, you need to understand that mastery of practice does not guarantee that you will not freeze anywhere and never. The condition changes and many factors affect. But, the likelihood of getting into trouble from the weather is still reduced. Just as the likelihood of being physically deflated for an athlete is differently lower than that of a squishy.

Alas, it was not possible to create a complete article. I just outlined this practice in general terms (more precisely, a complex of practices, because diving into an ice hole, jogging in a T-shirt in the cold and strolling through the woods in the Mowgli style are different). Let me summarize where I started. Owning your own resources allows you to get rid of fears and feel much more comfortable. And this is interesting.

Dmitry Kulikov