It is known that the changes in time sphere of the organism functioning reflect the dynamics of its functional state. But the traditional method of analysis examine only the stational element of the process. But more perspective methods for studying the objective data of the dynamic changes of ECG features are the methods which examine not only stational but non-stational of the ECG components too. One of the informative approaches to the evaluation of the non-stationary and to the definition of its character (random or determined) is the usage of the chaos theory methods.

In the course of the study it was necessary to clarify how such factors as temperate climate or not climate influence upon the level of ECG chaos. The analysis of the obtained data demonstrated that in the case of sharp adaptation to the hot climate the decrease of the ECG chaos level was marked in comparison with the data obtained in the conditions of the temperate climate. And here the dynamics of the chaos cardiointervals changes has clearly marked wave character. It means that there is the reconstruction of the time structure of cardinal rhythm in the process of sharp adaptation.