Figure 4: RR interval and systolic blood pressure plotted in time series for pre-, during- and post-alternate nostril breathing (ANB). Based on the sign changes in RR interval, vertical bars (continuous) have been plotted to depict time correspondence of RR interval and systolic blood pressure. Solid vertical bars indicate that both events are happening simultaneously without any phase lag. Dotted vertical bars indicate the phase lag between RR interval and systolic blood pressure. Simultaneous rise and fall of blood pressure and RR interval and 0° phase relationship were evident in pre- and post-ANB and in the initial part of during-ANB. Systolic blood pressure preceded changes in RR interval during-ANB, indicating alteration in phasic relationship, which lasted little over in post-ANB.