Background. Typically, the step test is used to assess the physical performance that is determined by the condition of the cardio-respiratory system. The latter, in turn, is associated with the nervous, endocrine and immune systems, which collectively determine the level of adaptation of the body. The purpose of this study is to analyze the effect on the step test of natural adaptogens and associated changes in a number of parameters of cardio-respiratory, autonomic nervous and immune systems and metabolism. Material and methods. The target was 80 children of both sexes, ages 10-17, arriving at the clinical sanatorium "Dzherelo" of Truskavets spa from radionuclide contaminated territories. The main subject of the study was the Popovych's step test. State of autonomous nervous and immune systems was assessed as well as others functional and metabolic tests. Results. The contingent surveyed was retrospectively divided into three qualitatively distinct groups. The largest group (53,7%) was the group of children with initially reduced or normal levels of Popovych's Step Test Index (PSI), in which it increased. However, in 28,8% of children PSI remained stable at different initial levels, and in 17,5% even decreased, without falling below the lower limit of normal. Discriminant analysis was subsequently applied to identify constellations of parameters that change are characteristic of each cluster. The program selected as characteristic changes in 2 parameters of autonomous nervous system, 2 functional, 4 metabolic and 3 immune parameters as well as blood trombocytes level. The correct classification of the positive actotropic effect is 93,0%; neutral 65,2%; negative 64,3%, and total correctness is 80,0%. Conclusion. Balneotherapy causes multivariate changes in Popopvych's step test, which accompanied by characteristic changes in certain parameters of autonomous nervous and immune systems as well as others functional and metabolic tests.

Background. We have previously shown that nitrogenous metabolites have immunomodulatory effects, both suppressor and enhancing, both in healthy rats and in humans exposed to pathogenic influences. The immunomodulatory effect of bilirubin is probably mediated through aryl hydrocarbon receptors, and uric acid through TL-and adenosine receptors of immune cells. The question of mediators of the immunomodulatory action of urea and creatinine remains open. We hypothesized the mediating role of mediators of the autonomic nervous system and adaptation hormones. The aim of this study is to analyze the relationships between the parameters of nitrogenous metabolites, on the one hand, and HRV markers of the parameters of the autonomic nervous system -on the other hand. Material and methods. The object of observation in 1997 were 19 men and 3 women who were exposed to pathogenic factors of the accident at the Chоrnobyl nuclear power plant during the liquidation of its consequences in 1986-87. The survey was conducted twice -on admission and after two weeks of rehabilitation at the Truskavets' Spa. The plasma and urinary concentration of the nitrogenous metabolites were determined. The state of the autonomic nervous system (ANS) was judged by the HRV parameters recorded before and after submaximal bicycle ergometric loading. Results. Both negative and positive metabolic-ANS correlations were revealed. Calculation of multiple correlation coefficients between individual metabolite parameters and constellations of HRV parameters revealed the maximum vegetotropic effect of Urea plasma (R=0,700) and Uric acid urine (R=0,623). This is followed by Urea urine (R=0,531) and Creatinine plasma (R=0,457). No significant correlations were found for Creatinine urine, Uric acid plasma and Bilirubinemia. The canonical correlation between the constellation of nitrogenous metabolites, on the one hand, and the HRV markers of ANS, on the other hand, was strong: R=0,747; χ 2 (28)=63; p<10 -3 . Conclusion. Previously identified immunomodulatory effects of urea and creatinine are realized, possibly through cholinergic and adrenergic mechanisms.