Acute effects on cardiovascular oscillations during controlled slow yogic breathing

Area of Science:

• Physiology
• Autonomic Nervous System
• Cardiovascular Regulation

Background:

• Breathing exercises are hypothesized to influence cardiovascular oscillations.
• Understanding the autonomic mechanisms underlying these effects is crucial.

Purpose of the Study:

• To investigate the impact of controlled slow yogic breathing (Alternate Nostril Breathing - ANB) on key autonomic regulatory parameters.
• To assess changes in Heart Rate Variability (HRV), Blood Pressure Variability (BPV), and Baroreflex Sensitivity (BRS).

Main Methods:

• Twelve healthy volunteers participated in the study.
• ANB was performed at a controlled frequency of 5 breaths per minute.
• Electrocardiogram, beat-to-beat blood pressure, and end-tidal carbon dioxide were recorded before, during, and after ANB.

Main Results:

• ANB significantly increased HRV, indicated by higher standard deviation of NN intervals and LF component, and a decreased HF component.
• BPV analysis revealed a significant increase in total power for systolic and diastolic blood pressure variability.
• BRS analysis showed increased sequences and augmentation of the LF component (α-LF) during ANB.

Conclusions:

• The study indicates a dynamic interaction between the respiratory and cardiovascular systems during ANB.
• Enhanced cardiovascular oscillations and baroreflex recruitment suggest complex, multi-mechanism coupling.
• These findings highlight the role of mechanical coupling, baroreflex, and central control in respiratory-cardiovascular interactions.