To problem of astronauts adaptation

M.R.Khaibullin, R.A.Gareyev

Institute of human and animals physiology

 

One of the major problems of aerospace medicine is development of methods of increase and preservation of organism adaptability in conditions of space flight, and also early identification and correction of possible malfunctions. Thus vegetative reactions should be studied which are associated with energy metabolism and psychophysiological processes. However, not all the psychophysiological reactions of energy metabolism are equally important during adaptation. The most important are reactions of thermolysis from body surface to environment (at interpretation of numerical data on their dynamics in comparison e.g. with cardiac rhythm and lungs ventilation).

Biological rhythms research deepens opportunities for prenosological diagnostics and opens ways for rational organization of work, rest and treatment. Recent successes enable application of some new methodological approaches in diagnostics, e.g. chronodiagnostics of certain organism's real time capacities for adaptive resources. Chronomedicine has received objective quantitative criteria based on research of an organism's biological cycles and used for estimation of transient states (from health to disease) on the level of preclinical health malfunctions, and estimation of individual and collective health.

We analyzed the change of galvanic skin response (GSR) in conditions of prolonged space flight (orbital experiment <Tangr>). During the flight a cosmonaut recorded GSR every minute within 3 hours three times (9 hours of measurements in general). Acquired results were analyzed from the position of high-frequency (minute) and circadian biorhythms.

Analyzing obtained data from positions of high-frequency biorhythms it is established that in the first series of measurements of <Tangr> experiment (the 5 ^th month of flight) alternation of three and seven minute rhythms was observed with slight domination of the latter ones. It testified to full adaptation of the cosmonaut to flight conditions. However, in the second half of experiment the amplitude of GSR fluctuations on a background of seven minute rhythm abruptly increased. Such combination is typical for the period of exhaustion, probably after performance of continuous routine (every minute measurements and data recording). Preservation of seven minute rhythm characterizes good adaptive abilities as adaptive changes are provided with increase in fluctuations amplitude. In the second series of measurements (the 6^th month of flight) the first quarter of experiment is characterized by high amplitude of fluctuations on a background of seven minute rhythm with single decaminute ones. These changes could be caused by some after preceding hard work at orbital station. Obtained data characterize occurrence of the first pronounced signs of desynchronosis. However, gradual restoration of normal biorhythmological picture by the end of experiment indicates satisfactory compensatory capabilities after a short rest. In the third series of measurements (the 7^th month of flight) strengthening fluctuation amplitude is observed on a background of seven minute rhythm, and in the second half of experiment - on the background of decaminute rhythm. The given changes specify further development of desynchronosis attributes.

Obtained data convincingly show development of desynchronosis of cosmonaut's circadian and high-frequency rhythms at long space flights. Identification of changes in structure of high-frequency biorhythms is more available and prompt, and this gives certain advantages in conditions of time deficit (during orbital flight and in other extreme cases).

We offer a method for estimation of adaptive capabilities of an organism to various influences by comparison of biorhythmological pictures after the impact and recovery of initial picture.

Obtained data can be applied not only for correction of functional condition of healthy people under increased physical and psychological stress (cosmonauts, pilots, sportsmen, rescuers, etc.). The given method is also applicable for increase of treatment efficiency, in case if disease is accompanied by distortions of biorhythmological pictures.

According to obtained materials, high-frequency rhythms are successfully used for estimation and forecasting of an organism state. At the same time these data prove that diagnostic and forecasting abilities of high-frequency rhythms are far from exhaustion. Further development of this field will expand knowledge of biological rhythms, and will also promote wider introduction of biorhythmological methods and approaches to experimental and clinical medicine.