EFFECT OF LOCAL HYPOTHERMIA ON THE NEURO-MUSCULAR SYSTEM IN WOMEN

Introduction: Many studies on adaptation of the human body to the effects of cold suggest the presence of evolutional genetic mechanisms of adaptation to the climate of the North. However, the question remains open about the reactions of the human neuromuscular system (NMS) to local hypothermia. Aim: To study the changes of the parameters of the NMS (coordinates xi = xi (t) of the tremorograms) of a group of young women living in the North of the Ugra republic, Russia before and after local cooling of the hand in different seasons. Methods: Kinematograms of tremor of the fingers of the right hand were recorded using a biophysical measuring complex based on the «Tremograph» device. Limb displacement signals x1 = x1 (t) were recorded and processed (obtaining the derivative of x1, i.e., x2 = v (t) = dx1/dt is the coordinate of the finger's speed of movement) using software products applying fast Fourier transformation and Wavelett-analysis. Shapiro-Wilk's tests and Wilcoxon tests were used for statistical analysis of the data. Results: All parameters of tremorograms of the neuromuscular system of women were had skewed distributions. The signal was always unique for each recording interval for every study participant. Medians of the parameters of the tremorograms in a group of women after local hypothermia in the autumn and spring periods of the year were reduced in 85-70 % of cases, but in spring these values were much greater both before and after local cold exposure compared to the autumn period. In 57 % of cases, the coordinates xi = xi (t) of the parameters of tremorograms were statistically different. Conclusions: Our findings suggest that the response of the NMS in women significantly varies across the seasons, which may indicate adaptation of the body to exposure to cold.

tremorograms, local hypothermia, cold exposure, seasons, adaptation