The aim of the present study was to determine the interrelationship among the baroreflex sensitivity, the variability in systolic blood pressure and pulse intervals at the frequency of 0.1 Hz. The study proved that pulse interval variability correlates with BRS and has a damping effect on SBP variability. Our analysis disloced an additional effect of a primary variability of systolic blood pressure on this relationship. The sequence of groups showed that BRS is more closely related to the variability in pulse intervals than in systolic blood pressure.