CAPTURE AND WITHHOLDING OF HEART RATE VARIABILITY INDEXES WITH PACED BREATHING IN HEALTHY VOLUNTEERS

At 4 healthy volunteers in age from 22 to 29 years (2 men and 2 women) with the body mass index from 21 to 23 kg/m2 frequency dependence of spectral indexes of heart rate variability (HRV) on at different paced breathing patterns were studied. It is shown that at the unidirectional breath rate changes (growth, decline) a capture and withholding of regulation contours occurs, realized through the change of spectral indexes of HRV. A capture and withholding of heart rate, however, did not occur. Paced breathing with 6-8 breathings per minute results in strengthening of LF domain of HRV, and 10-12 breathings per minute ? HF domain of HRV; paced breathing with 9 breathings per minute result in activation of both HRV domains. To recieve adequate pattern of capture and withholding of regulation contour usage of duration of breathing step and capacity of HRV buffer ? 1 minute and a speed of change of breathing frequency ? 1 breathing per minute is enough. Application of breathing patterns with these parameters can be the handy instrument of rapid and effective selection of optimum frequency of breathing for ?fine tuning? of regulatory systems activity.