Rhythmicity in biology. The importance of biological rhythms. Human Biorhythms

Science, studying rhythm in biology, emerged in the late XVIII century. Its founder is the German physician Christopher William Gufelyand. From its submission for a long period, the biological rhythms of the organism were considered to be dependent solely on external cyclic processes, primarily on the rotation of the Earth around the Sun and its own axis. Today chronobiology is popular. According to the dominant theory in it, the causes of biorhythms lie both outside and inside a particular organism. And the changes, which are repeated in time, are peculiar not only to individual individuals. They permeate all levels of biological systems - from the cell to the biosphere.

Rhythmicity in Biology: Definition

Thus, the property under consideration is one of the fundamental characteristics of living matter. Rhythmicity in biology can be defined as fluctuations in the intensity of processes and physiological responses. It represents periodic changes in the state of the environment of a living system that arise under the influence of external and internal factors. Also they are called synchronizers.

Biorhythms that do not depend on external factors acting on the system outside are endogenous. Exogenous, respectively, do not respond to the effect of internal (operating within the system) synchronizers.

Causes

As already noted, at the first stages of the formation of a new science, rhythmicity in biology was considered to be conditioned only by external factors. This theory was replaced by the hypothesis of internal determinism. In it, external factors were assigned an insignificant role. However, rather quickly, researchers came to understand the high value of both types of synchronizers. Today it is believed that the biological rhythms of life, endogenous by nature, are subject to changes under the influence of the external environment. This idea stands at the center of a multi-oscillatory model for the regulation of such processes.

The essence of the theory

According to this concept, endogenous genetically programmed oscillatory processes are affected by external synchronizers. A huge number of internal rhythmic vibrations of a multicellular organism is built in a certain hierarchical order. At the heart of its maintenance are neurohumoral mechanisms. They coordinate the phase relationships of different rhythms: unidirectional processes proceed synchronously, and incompatible ones work in antiphase.

All this activity is difficult to imagine without an oscillator (coordinator). In this theory, three interrelated regulatory systems are distinguished: epiphysis, pituitary gland and adrenal glands. The epiphysis is considered the most ancient.

Presumably in organisms that stand at low levels of evolutionary development, the epiphysis plays a major role. The melatonin produced by him is produced in the dark and decays in the light. In fact, he tells all the cells about the time of day. With complication of the organization, the epiphysis begins to play a second role, yielding supremacy to the suprachiasmatic nuclei of the hypothalamus. The question of the relationship in the regulation of biorhythms of both structures has not been fully resolved. In any case, according to theory, they have an "assistant" - the adrenal glands.

Kinds

All biorhythms are divided into two main categories:

• Physiological represent fluctuations in the work of individual systems of the body;

• Ecological, or adaptive are necessary to adapt to the constantly changing environmental conditions.

Also common is the classification proposed by the chronobiologist F. Halberg. As a basis for the separation of biological rhythms, he took their duration:

• Fluctuations in high frequency - from a few seconds to half an hour;

• Fluctuations in the average frequency - from half an hour to six days;

• Fluctuations of low frequency - from six days to a year.

Processes of the first type are breathing, palpitation, electrical activity of the brain and other similar rhythm in biology. Examples of fluctuations in the mean frequency are changes during the day of metabolic processes, sleep and wakefulness. The third type of oscillation includes seasonal, annual and lunar rhythms.

External synchronous to the person synchronizers are divided into social and physical. The first is the daily routine and the various norms adopted in the workplace, in the home or in society as a whole. Physical synchronizers are represented by a change of day and night, the intensity of electromagnetic fields, fluctuations in temperature, humidity, and so on.

Desynchronization

The ideal state of the body occurs when the internal biorhythms of a person work in accordance with external conditions. Unfortunately, this is not always the case. The state, when there is a mismatch between internal rhythms and external synchronizers, is called desynchronosis. It also exists in two variants.

Internal desynchronosis - mismatch processes directly in the body. A common example is the violation of the rhythms of sleep and wakefulness. External desynchronosis is a mismatch of internal biological rhythms and environmental conditions. Similar violations occur, for example, when flying from one time zone to another.

Desynchronosis manifests itself in the form of changes in physiological parameters such as blood pressure. Often it is accompanied by increased irritability, lack of appetite, rapid fatigue. According to chronobiologists, as already mentioned above, any disease is the result of a mismatch of various oscillatory processes.

Daily biological rhythms

Understanding the logic of fluctuations in physiological processes makes it possible to optimally arrange activities. In this sense, especially important is the importance of biological rhythms lasting about a day. They are used both to determine the effective mode of work and rest, and for medical diagnosis, treatment, and even the choice of dose of drugs.

In the human body, the day is the period of oscillation of a huge number of processes. Some of them change significantly, others - minimal. It is important that the indicators of both do not go beyond the norm, that is, they do not become threatening to health.

Temperature fluctuations

Thermoregulation is the guarantee of the constancy of the internal environment, and hence the proper functioning of the organism for all mammals, including humans. The change in temperature takes place during the day, with the range of oscillations quite small. Minimal indicators are typical for the period from one o'clock in the morning to five in the morning, the maximum is recorded at about six o'clock in the evening. The amplitude of the oscillations is, in this case, often less than one degree.

Cardiovascular and endocrine systems

The work of the main "motor" of the human body is also subject to fluctuations. There are two time points, in which the activity of the cardiovascular system decreases: an hour of the day and nine in the evening.

Their rhythms are characteristic of all organs of hematopoiesis. The peak of bone marrow activity is in the early morning, and the spleen is at eight o'clock in the evening.

The secretion of hormones is also unstable throughout the day. The concentration of adrenaline in the blood rises early in the morning and reaches its peak at nine o'clock. This feature explains the vivacity and activity that are most common to people in the morning.

Midwives know curious statistics: labor activity in most cases begins around midnight. This is also associated with the peculiarities of the endocrine system. By this time, the posterior lobe of the pituitary gland, which produces the corresponding hormones, is activated.

In the morning - meat, in the evening - milk

For followers of proper nutrition, the facts related to the digestive system will be interesting. The first half of the day is the time when the peristalsis of the gastrointestinal tract becomes worse, the production of bile increases. The liver actively consumes glycogen in the morning and gives water. From these patterns chronobiologists derive simple rules: heavy and fatty food is better in the morning, and after dinner and in the evening, dairy products and vegetables are ideal.

Working capacity

It's no secret that human biorhythms affect its activity during the day. Oscillations vary from person to person, but general patterns can also be identified. Three "bird" chronotypes, connecting biological rhythms and working capacity, perhaps, are known to all. This is the "lark", "owl" and "dove". The first two are extreme options. "Larks" full of strength and energy in the morning, easily get up and go to bed early.

"Owls", like their prototype, are nocturnal. The active period for them begins at about six in the evening. Early rise is very difficult for them to endure. "Pigeons" are able to work both in the afternoon and in the evening. In chronobiology they are called arrhythmics.

Knowing your type, a person can more effectively manage their own activities. However, there is an opinion that any "owl" can become a "lark" if desired and perseverance, and the division into three types is conditioned, rather, by habits, rather than laid down features.

Constant change

Biorhythms of man and other organisms are not rigid, permanently fixed by signs. In the process of onto- and phylogenesis, that is, individual development and evolution, they change with certain regularities. What is responsible for such shifts, to the end is still unclear. There are two main versions in this respect. According to one of them, the changes laid at the cellular level are guided by changes - it can be called a biological clock.

Another hypothesis assigns the main role in this process to geophysical factors that have yet to be studied. Adherents of this theory explain the differences in individual biorhythms by their position on the evolutionary ladder. The higher the level of organization, the more intensive the metabolism. In this case, the character of the indices does not change, but the amplitude of the oscillation increases. The very rhythm in biology and its synchronization with geophysical processes, they consider as the result of the work of natural selection, leading to the transformation of the external (for example, the change of day and night) into the internal (activity and sleep) rhythm fluctuation.

The influence of age

Chronobiologists managed to establish that in the process of ontogenesis, depending on the stage passed by the organism, the circadian rhythms change. Each period of postnatal development corresponds to its fluctuations in internal systems. Moreover, the change in biological rhythms is subject to a certain pattern, described by the Russian specialist G.D. Gubin. It is convenient to consider it on the example of mammals. At them similar changes are connected first of all with amplitudes of circadian rhythms. From the first stages of individual development, they grow and reach a maximum in young and adulthood. Then the amplitudes begin to decrease.

These are not the only changes in rhythms associated with age. The sequences of acrophases also change (acrophase is the point of time when the maximum value of the parameter is observed) and the magnitude of the range of the age norm (chronodesm). If we take into account all these changes, it becomes obvious that it is in adulthood that biorhythms are perfectly coordinated and the human body is able to withstand various external influences while preserving one's health. Over time, the situation is changing. As a result of mismatching different rhythms, the health reserve gradually ends.

Chronobiologists suggest using similar patterns for disease prediction. On the basis of knowledge of the peculiarities of fluctuations in circadian rhythms of a person during a lifetime, it is theoretically possible to construct a certain graph reflecting the health reserve, its maxima and minima in time. Such testing is a matter of the future, according to most scientists. However, there are theories that allow you to build something like this schedule now.

Three rhythms

Let us slightly open the veil of secrecy and tell you how to determine your biorhythms. Calculation in them is done on the basis of the theory of the psychologist Herman Svoboda, physician Wilhelm Fiss and engineer Alfred Telcher, created by them at the turn of the XIX and XX centuries. The essence of the concept is that there are three rhythms: physical, emotional and intellectual. They occur at the time of birth and throughout their lives do not change their frequency:

• Physical - 23 days;

• Emotional - 28 days;

• Intellectual - 33 days.

If you plot the changes over time, it will take the form of a sinusoid. For all three parameters, a part of the wave above the Ox axis corresponds to an increase in the indices, underneath it there is a zone of decline in physical, emotional and mental capabilities. Biorhythms, the calculation of which can be made on a similar schedule, at the point of intersection with the axis signal the beginning of a period of uncertainty, when the resistance of the organism to the influences of the environment is greatly reduced.

Definition of indicators

Calculation of biological rhythms based on this theory can be done independently. To do this, you need to calculate how much you have already lived: multiply the age by the number of days in a year (do not forget that there are 366 of them in a leap year). The resulting figure should be divided by the frequency of the biorhythm, the plot of which you are building (23, 28 or 33). We get some integer and remainder. The whole part again multiply by the duration of a specific biorhythm? F subtract from the number of days lived. The remainder is the number of days of the period at the moment.

If the value obtained does not exceed one-fourth of the cycle time, this is the rise time. Depending on the biorhythm, it involves cheerfulness and physical activity, good mood and emotional stability, creative inspiration and intellectual growth. A value equal to half the length of the period symbolizes the time of uncertainty. Hitting the last third of the duration of any biorhythm means finding in the zone of decline activity. At this time, people tend to get tired faster, the danger of disease increases, if it is a question of the physical cycle. In the emotional plan, there is a decrease in mood right up to depression, a deterioration in the ability to restrain strong internal impulses. At the level of the intellect, the period of decline is characterized by difficulty in making decisions, a certain inhibition of thought.

Relationship to theory

In the scientific world, the concept of three biorhythms in this format, as a rule, is criticized. There is not sufficient evidence to suggest that in the human body, something can be so unchanged. This is evidenced by all the observed regularities, which are subject to rhythm in biology, the characteristics of internal processes inherent in different levels of living systems. Therefore, the described calculation methodology and the whole theory is most often considered to be an interesting variant of pastime, but not a serious concept based on which one should plan its activities.

The biological rhythm of sleep and wakefulness, therefore, is not the only one that exists in the body. All systems that make up our body are subject to fluctuations, not only at the level of such large formations as the heart or lungs. Rhythmic processes are laid in the cells, and therefore inherent in living matter in general. The science that studies such oscillations, while young enough, is already trying to explain many of the patterns that exist in human life and in all nature. Already accumulated data suggest that the chronobiology potential is in fact very high. Perhaps in the near future its principles will be guided by doctors, prescribing doses of drugs in accordance with the peculiarities of the phase of a particular biological rhythm.