Physiological and Neurodynamic Effects of Bhramari Pranayama: Study Based on HRV and EEG Activity

This pilot study investigated the acute effects of a single session of bhramari pranayama (humming bee breath) on heart rate variability (HRV) and electroencephalographic (EEG) activity in healthy adults. Twenty participants performed a 5-minute session of bhramari pranayama. HRV was assessed using time-domain (standard deviation of NN intervals, root mean square of successive differences [RMSSD], percentage of successive NN intervals that differ by more than 50 milliseconds [pNN50]) and frequency-domain (low-frequency [LF] power, high-frequency [HF] power, LF:HF) parameters. EEG was recorded simultaneously to measure spectral power in delta, theta, alpha, beta, and gamma bands. Statistical analysis included paired t tests and Wilcoxon tests based on normality assessment. Significant increases were observed in parasympathetic markers including RMSSD (29.95 ± 6.03 ms to 45.83 ± 8.72 ms, p < 0.0001) and pNN50 (8.71% ± 7.24% to 19.93% ± 8.28%, p = 0.0010). LF power increased substantially (300 ± 118 ms2 to 4843 ± 1470 ms2, p = 0.0001), with the LF:HF ratio rising from 0.8 ± 0.31 to 11.03 ± 4.0 (p = 0.0001). EEG showed decreased delta (49.57 ± 13.48 to 12.29 ± 6.24, p < 0.0001) and theta waves, alongside increased beta and gamma activity, suggesting a state of cortical alertness. A single session of bhramari pranayama was associated with increased parasympathetic activity and shifts in brainwave patterns toward heightened alertness. Although these preliminary findings are promising, the uncontrolled design and small sample size limit generalizability. Further controlled studies are needed to confirm these effects and explore therapeutic potential.