Power Spectral Analysis of R-R Interval Variability during Zazen

Abstract

This study was designed to evaluate the influence on autonomic nervous activity caused by "zazen"which is one kind of mental and physical training method. Seven monks belonging to the Soto-shu Sect rested for 40 min.and practiced zazen for 40 min.in one day. Then R-R interval variability was evaluated by power spectral analysis. In the two tests, the power spectrum in the high frequency band(HF)during zazen was higher than resting but not significantly, and the ratio of the low frequency band to the high frequency band(LF/HF)during resting was higher than during zazen but not significantly, and the slope of 1/f^β fluctuation during zazen was significantly more gentle than resting. These results indicated the parasympathetic nervous system was more activated during zazen than during resting.