V.A. Orlov, N.A. Sadykova, N.V. Lysenko

In the article theoretical prerequisits of a method based on enegy metabolism processes, on a balance between catabolic and anabolic processes proceeding in human organism and connected with energy accumulation and expenditure are cited. Vegetative nervous system (VNS), its sympathetic and parasympathetic sections are responsible for these two processes. On observing the correlation of interaction between these two sections one can indirectly control energy reserve in human organism, interaction extent being observed using heart work dispersion characteristics, its oscillating condition. An operator functional condition estimation method based upon recognition and measuring temporal intervals between electrocardiographic R-waves (RR-intervals), cardiointervals (CI) dynamic series construction and consequent obtained numerical series analysis using mathematical method, is considered. CI duration values temporal (statistical) analysis method is used. Distribution law of a random process such as a heart rate is presented as a step function - a bar graph that can be described with a set of computable statistic parameters and diagnostic indicators showing VNS activity. Two such indicators are presented in the article: regulation system tension index proposed by R.M.Baevsky; improved heart rate index proposed by M.E.Lifshiz. As a result of the research it was established that the following process parameters dramatically influence upon value and stability of tension index: dimension of RR-intervals set being processed; authenticity of the set being processed; dimension of the frame for a mode value estimation; RR-intervals detachment accuracy value. Each of the parameters is considered in detail.