title: [Nonstationarity and duration of the R-R-segment in the diagnostics of functional states of operators].
abstract: The effect of the nonstationarity of R-R interval series on the diagnostics of functional states of operators has been analyzed. The functional states were diagnosed by means of a factor model of heart rate variability. The heart rate was recorded in the supine position, before the performance of an important task, and after its completion. A high resistance of the diagnostics of functional states to nonstationarity was found for all periods. Indices of heart rate variability resistant to nonstationarity were defined. Also, the effect of R-R segment duration on functional states diagnostics was explored. The results obtained allow one to conclude that the diagnostics of functional states based on the three-factor model of heart rate variability can be used on short segments within a range of 256 divided 32 R-R intervals. The indices of the factor model of heart rate variability must be normalized for corresponding R-R segment duration before diagnostics. In addition, the effect of the duration of R-R segment on the indices of heart rate variability was analyzed for different functional states. The indices resistant to the duration of R-R segments and conditions necessary for heart rate recording were defined.
authors.forename: V A
authors.initials: VA
authors.lastname: Mashin
mesh_terms: D004562:Electrocardiography; D006321:Heart / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D011210:Power Plants; D000078329:Workforce