Many biological processes in nature proceed rhythmically, i.e., different states of the body alternate with a fairly clear periodicity. Examples of fast rhythms are heartbeats or breathing movements with a period of only a few seconds. Other vital rhythms, such as the alternation of wakefulness and sleep, have a period of about a day. If biological rhythms are synchronized with the onset of high and low tides (every 12,4 hours) or only one of these phases (every 24,8 hours), they are called tidal. In lunar biological rhythms, the period corresponds to the duration of the lunar month, and in annual rhythms, to the year. Heartbeats and other forms of rapid rhythmic activity that do not correlate with natural changes in the environment are usually studied by physiology and will not be discussed in this article.
Biological rhythms are interesting because in many cases they persist even under constant environmental conditions. Such rhythms are called endogenous, i.e. “coming from within”: although they usually correlate with rhythmic changes in external conditions, such as the alternation of day and night, they cannot be considered a direct reaction to these changes. Endogenous biological rhythms are found in all organisms except bacteria. The internal mechanism that maintains the endogenous rhythm, that is, allows the body not only to feel the passage of time, but also to measure its intervals, is called the biological clock.
The work of the biological clock is now well understood, but the internal processes underlying it remain a mystery. In the 1950s, the Soviet chemist B. Belousov proved that even in a homogeneous mixture, some chemical reactions can periodically speed up and slow down. Similarly, alcoholic fermentation in yeast cells is switched on and off at intervals of about 30 seconds. Somehow these cells interact with each other so that their rhythms are synchronized and the whole yeast suspension “pulsates” twice a minute.
It is believed that this is the nature of all biological clocks: chemical reactions in every cell of the body proceed rhythmically, the cells «adjust» to each other, that is, they synchronize their work, and as a result they pulsate simultaneously. These synchronized actions can be compared to the periodic oscillations of a clock pendulum.
The science of «chronobiology» is engaged in the study of the rhythms of life («chronos» — time, «bios» — life). Although this science is relatively young (about 100 years old), it represents a number of important achievements, including:
- Identification of biological rhythms at all levels of the organization of living nature — from unicellular to the biosphere. This indicates that biorhythm is one of the most common properties of biosystems.
- Recognition of biorhythms as a mechanism for regulating body functions, providing homeostasis, dynamic balance and adaptation processes in biological systems.
- Establishing a connection between biological rhythms of an endogenous nature (internal, inherited) with modifying environmental factors. This connection, at the basis of the unity of the organism with the environment, largely determines the ecological patterns and vital activity.
- Formulation of the provision on the temporal organization of living systems, one of the basic principles of biological organization. The development of provisions on the influence of biological rhythms is very important for the analysis of pathologies of biosystems (including the human life cycle).
- Detection of biological rhythms of the body’s sensitivity to the action of factors of a chemical and physical nature. This became the basis for the development of chronopharmacology — a methodology for the use of drugs, taking into account the dependence of their action on the phases of the life cycle.
Biorhythms (biological rhythms) of a person
3.00 — 6.00: the most difficult period for the body. This period is characterized by the lowest level of blood pressure.
6.00 — 7.00 am: This is the best time to go from sleep to wakefulness.
5.00 — 7.00 am: the best time to cleanse the body, as well as the period of maximum activity of the large intestine.
7.00 — 9.00 am: A good time to eat, as this is the time when the stomach is most active.
8.00 — 9.00: the concentration of hormones in the blood increases.
9.00 — 10.00: the period in which the human skin is less sensitive. Therefore, it is the most suitable period for medical procedures.
10.00 — 12.00: the optimal time for intellectual work, as the brain is most active at this time.
13.00 — 15.00: the time of the greatest activity of the small intestine. Food is digested more efficiently.
16.00 — 18.00: the best time for sports and physical work. Nails and hair grow the fastest.
17.00 — 19.00: the time when the nuances of aromas, music and taste are best captured.
18.00 — 20.00: The liver is more efficient in dealing with alcohol. The skin is also the most sensitive to cosmetic procedures.
18.00 — 21.00: time for friendly conversations. A person most acutely feels loneliness and is open to communication.
19.00 — 21.00: the best time for yoga and stretching and relaxation exercises, as our joints are as mobile as possible.
22.00 is a favorable time for going to bed. The body’s defenses are most intensively activated.