Enhancement of cardiac autonomic nervous system activity by blood flow restriction in the human leg

抄録

The purpose of this study is to develop a unique method to enhance autonomic nervous system (ANS) activity by means of experimental leg occlusion. The effects of blood flow restriction on the activities of the ANS during rest were investigated using a power spectral analysis of heart rate variability. Two patterns of occlusion were randomly assigned to healthy subjects: pattern A, 10 min of 1.4 times of systolic blood pressure; pattern B, 5 min of mean blood pressure followed by 5 min of 1.4 times of systolic blood pressure. Electrocardiogram, blood pressure and cardiac output were continuously monitored during rest and occlusion. During occlusion, cardiac output and stroke volume showed significant decreases, due to modulation of autonomic nervous activity. After releasing from occlusion without blood pooling (A), the high frequency component of R-R interval variability representing vagal activity showed a significant increase (P<0.05). However, soon after releasing, the ECG QTc interval temporally prolonged (P<0.05) and recovered gradually. Further investigation is recommended to determine blood flow occlusion safety on the cardiac depolarization-repolarization process. In conclusion, the results suggest that blood flow restriction has potential to be a useful method to stimulate the activity of autonomic nervous system, and especially to enhance parasympathetic nervous system activity.