Acute effects of resonance frequency breathing on cardiovascular regulation. Issue 22 (28th November 2019)

• Record Type: Journal Article
• Authors: Pagaduan, Jeffrey; Wu, Sam SX; Kameneva, Tatiana; Lambert, Elisabeth
• Is Part Of: Physiological reports. Volume 7:Issue 22(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-11-28
• Subjects: baroreflex -- blood pressure -- resonance frequency -- sympathetic nervous activity; Physiology -- Periodicals; 571
• DOI: 10.14814/phy2.14295
• Languages: English
• ISSNs: 2051-817X

Abstract

Abstract: Acute slow breathing may have beneficial effects on cardiovascular regulation by affecting hemodynamics and the autonomic nervous system. Whether breathing at the resonance frequency (RF), a breathing rate that maximizes heart rate oscillations, induces differential effects to that of slow breathing is unknown. We compared the acute effects of breathing at either RF and RF + 1 breaths per minute on muscle sympathetic nervous activity (MSNA) and baroreflex function. Ten healthy men underwent MSNA, blood pressure (BP), and heart rate (HR) recordings while breathing for 10 min at their spontaneous breathing (SB) rate followed by 10 min at both RF and RF + 1 randomly assigned and separated by a 10‐min recovery. Breathing at either RF or RF + 1 induced similar changes in HR and HR variability, with increased low frequency and decreased high frequency oscillations ( p < .001 for both). Both respiration rates decreased MSNA (−5.6 and −7.3 bursts per min for RF and RF + 1 p < .05), with the sympathetic bursts occurring more often during mid‐inspiration to early expiration (+57% and + 80%) and longer periods of silence between bursts were seen ( p < .05 for RF + 1). Systolic BP was decreased only during RF (−4.6 mmHg, p < .05) but the decrease did not differ to that seen during RF + 1 (−3.1 mmHg). The sympathetic baroreflex function remained unchanged at either breathing rates. The slope of the cardiac baroreflex function was unaltered but the cardiac baroreflex efficiency was improved during both RF and RF + 1. Acute breathing at either RF or RF + 1 has similar hemodynamic and sympatho‐inhibitory effects in healthy men. Abstract : Slow breathing at either a fixed pace or at the exact resonance frequency are strategies commonly used to lower blood pressure or improve symptoms such as anxiety. Whether breathing at the precise resonance frequency or simply at a low pace induce different acute effects on the autonomic nervous system is unknown. We evaluated the acute effects of the two types of breathing exercise in young healthy men on blood pressure, sympathetic nervous system activity, and baroreflex function. We find that regardless of the breathing scheme, slow breathing induced sympatho‐inhibition, decreased blood pressure and improved the efficacy of the cardiac baroreflex function. Our study demonstrate for the first time that breathing at the resonance frequency induces changes in the cardiovascular regulation similar to that of breathing at a slow pace.