Single Slow-Paced Breathing Session at Six Cycles per Minute: Investigation of Dose-Response Relationship on Cardiac Vagal Activity

Abstract

The practice of slow-paced breathing (SPB) has been linked to a range of positive outcomes, such as decreasing symptoms of depression, anxiety, and stress, as well as increasing well-being. Among the suggested mechanisms of action, SPB has been shown to increase cardiac vagal activity (CVA). The present study aimed to investigate whether there is a dose-response relationship modulating the effects of SPB on CVA. A total of 59 participants were involved in this study. In a within-subject design, participants attended the lab five times, and realized SPB at six cycles per minute with different durations (5, 10, 15, and 20 min), as well as a control condition without SPB. CVA was indexed via the root mean square of successive differences (RMSSD). During SPB, findings showed an increase in RMSSD in all conditions compared to the control condition. However, no differences were found in RMSSD among the different session durations, during SPB or during the resting measurement completed immediately after SPB. Noteworthily, session duration showed an influence on the spontaneous respiratory frequency in the resting measurement occurring immediately after SPB. Specifically, respiratory frequency appears to decrease with session duration, thus potentially contributing to additional relaxing effects.

Slow breathing for reducing stress: The effect of extending exhale

“…No changes were noted at 12 breaths per minute. Another acute study similar increases in vagal tone among participants performing slow breathing, but no significant difference by varying inhale to exhale ratios 33 . A third study has tried to determine the ideal dose of slow breathing that would be most beneficial to increase cardiac vagal tone 34 .…”

“…Among a non-stressed population, E > I did not have a more significant effect. Prior research suggests there may be differences in acute autonomic tone changes with prolonged exhalation but normal breathing patterns 27 , 33 , 35 , or with different breath ratios, but long-term practice from yoga-based slow breathing has not been examined. Future studies need to be examined to see if slow breathing with different breath ratios have a significant effect among populations with higher psychological and/or physiological stress.…”

Squeeze the beat: Enhancing cardiac vagal activity during resonance breathing via coherent pelvic floor recruitment

“…In addition to amplified LF‐HRV, RB increases the root mean square of successive differences (RMSSD), which reliably indexes CVA across different respiratory frequencies (Penttilä et al, 2001 ; Shaffer & Meehan, 2020 ). Noteworthy, under resting conditions the magnitude of acute RMSSD augmentation occurring during a RB session seems independent of its duration and returns to pre‐session resting levels post‐practice (You, Laborde, Salvotti, et al, 2021 ; You, Laborde, Zammit, et al, 2021 ). On the contrary, respiration seems to be sensitive to session length with longer RB intervals yielding lower post‐session resting breathing rates, which in response could transfer to improved psychophysiological functioning (e.g., You, Laborde, Zammit, et al, 2021 ).…”

“…Noteworthy, under resting conditions the magnitude of acute RMSSD augmentation occurring during a RB session seems independent of its duration and returns to pre‐session resting levels post‐practice (You, Laborde, Salvotti, et al, 2021 ; You, Laborde, Zammit, et al, 2021 ). On the contrary, respiration seems to be sensitive to session length with longer RB intervals yielding lower post‐session resting breathing rates, which in response could transfer to improved psychophysiological functioning (e.g., You, Laborde, Zammit, et al, 2021 ). Importantly, practicing RB regularly has been shown to improve psychological and physical health as well as performance, which at least partly is attributed to the CVA‐enhancing effect of this distinct breathing pattern (Lehrer et al, 2020 ).…”

Women’s Respiratory Movements during Spontaneous Breathing and Physical Fitness: A Cross-Sectional, Correlational Study

“…Abdominal breathing is breathing that is dominated by the movement of the diaphragm that expands the abdominal wall if chest movement is controlled, while thoracic breathing is dominated by accessory inspiratory muscles (e.g., external intercostal muscles, scalenus, pectoralis, and sternocleidomastoid) that increase the diameter of the thoracic cavity [12,13]. Scientific research has found that abdominal breathing exercises are beneficial not only for mental health [14,15], but also for physical wellbeing (cited research as follows). Six-minute walking distance was significantly improved in COPD patients after abdominal breathing exercises, as concluded by a meta-analysis study [16].…”