The impact of controlled breathing on autonomic nervous system modulation: analysis using phase-rectified signal averaging, entropy and heart rate variability.

The present study investigated how breathing stimuli affect both non-linear and linear metrics of the autonomic nervous system (ANS).The analysed dataset consisted of 70 young, healthy volunteers, in whom arterial blood pressure (ABP) was measured noninvasively during 5 min sessions of controlled breathing at three different frequencies: 6, 10 and 15 breaths min. COconcentration and respiratory rate were continuously monitored throughout the controlled breathing sessions.