A collection of postings on a range of issues is available on our website (www.mjacksongroup.ca). This month’s post is again from Ken Pope’s listserv, where he kindly provides daily summaries of current articles in the field.Cell includes a study: “Brief structured respiration practices enhance mood and reduce physiological arousal.”
The authors Melis Yilmaz Balban, Department of Neurobiology, School of Medicine, Stanford University, et al.
Here’s how it opens:
Breathing is a life-sustaining bodily function, facilitating oxygenation and carbon dioxide disposal, but scientific studies on its significance for the mind-body connection have been limited. Embedded in ancient practices for centuries, breathwork has emerged as an intervention due to its reported health benefits. The COVID-19 pandemic highlighted the importance of simple, fast-acting, and cost-effective techniques to address widespread physical and mental health challenges and limited access to health care. While the neurobiology of breath has been studied both in animals and humans,1 little comparative data exist on the effects of different breathing techniques or the amount of breathing exercise that must be performed to produce those effects.
The pattern and depth of breathing have direct physiological impact on oxygenation level, heart rate, ventilation, and blood pressure.2 Slow breathing at a rate of six breaths per minute reduces chemoreceptor reflex response to hypercapnia and hypoxia compared with spontaneous respiration at 15 breaths per minute.3 Impairment of baroreceptor reflex sensitivity plays a role in the etiology of hypertension, and how we breathe has numerous other major health implications. Heart rate and blood pressure decrease with slow breath in patients with essential hypertension compared with higher-frequency breathing.4 Breathing training has also been shown to improve quality of life for asthmatics and to decrease use of bronchodilators.5 Furthermore, there is evidence that nasal breathing affects the CNS differently than mouth breathing. While nasal breathing synchronizes electrical activity in the olfactory cortex as well as amygdala and hippocampus, mouth breathing does not,6 which has implications for stress management and treatment of anxiety. Moreover, the mere act of inhaling has been shown to increase alertness levels and learning in humans.7
It is also clear that different emotional and cognitive states alter the depth and frequency of breathing,8,9,10,11,12 which likewise impacts emotional state, in part by regulation of carbon dioxide levels.13,14,15,16,17 There is growing evidence that brain-body states, ranging from sleep to stress to physical activity to meditation, can help people buffer and better manage stressors. A review of Yogic breathing practices reported increased feelings of peacefulness, improved reaction time and problem solving, decreased anxiety, and reduction of mind wandering and intrusive thoughts.18,19
Here’s the abstract:
Controlled breathwork practices have emerged as potential tools for stress management and well-being. Here, we report a remote, randomized, controlled study (NCT05304000) of three different daily 5-min breathwork exercises compared with an equivalent period of mindfulness meditation over 1 month. The breathing conditions are (1) cyclic sighing, which emphasizes prolonged exhalations; (2) box breathing, which is equal duration of inhalations, breath retentions, and exhalations; and (3) cyclic hyperventilation with retention, with longer inhalations and shorter exhalations. The primary endpoints are improvement in mood and anxiety as well as reduced physiological arousal (respiratory rate, heart rate, and heart rate variability). Using a mixed-effects model, we show that breathwork, especially the exhale-focused cyclic sighing, produces greater improvement in mood (p < 0.05) and reduction in respiratory rate (p < 0.05) compared with mindfulness meditation. Daily 5-min cyclic sighing has promise as an effective stress management exercise.
Here’s a graphical abstract:
Here’s how the Discussion opens:
We conducted a randomized controlled study to compare the psychophysiological effects of 5-min daily practice of three different breathing exercises and mindfulness meditation over 1 month. We assessed group differences in acute effects by using a linear mixed-effects modeling approach that took into account multiple measurements from each participant and the effect of adherence. We also looked at baseline and post-study measurements of sleep-related daytime disturbances, trait anxiety, and slopes of physiological measures throughout the study. We found differential effects of these exercises on both daily acute measures and physiological measures over the course of the study.
While all four groups showed significant daily improvement in positive affect and reduction in state anxiety and negative affect, there were significant differences between mindfulness meditation and breathwork in positive affect (Figures 2 and 3). Our daily monitoring and mixed-effects modeling approach allowed us to measure impacts throughout the study and revealed that the positive affect benefits of the breathwork exercises increased with more practice over time (Figure 2). Specifically, the cyclic sighing group showed more increase in positive affect toward the end of the study in a way that was significantly different than that for those randomized to mindfulness meditation, who had the least increase in positive affect (Figure 3). Overall, breathwork practices, particularly cyclic sighing, were more effective than mindful meditation in increasing positive affect, supporting our hypothesis that intentional control over breath with specific breathing patterns produces more benefit to mood than passive attention to one’s breath, as in mindfulness meditation practice.
Our study monitored subjects daily and collected daily physiological data remotely, a capability that was forced by the COVID restrictions but was enabled by the wearable technology that the WHOOP strap offered. The use of wearables enabled us to assess the changes longitudinally as opposed to just in two time points before and after the study and revealed differences in groups over time that would not be otherwise possible.58 It also allowed us to include a geographically diverse participant pool. A limitation of this remote study was having less control over some variables that may influence the results such as knowing how exactly the subjects practiced the exercises or controlling exactly how long they practiced. We advise future remote studies to take such variables into consideration. Overall, the study showed that remote administration of interventions is effective and that physiological monitoring is possible. Our results also support the importance of the discipline of daily practice to see substantial effects. Altogether, our study paves the way for deeper in-lab and remote mechanistic explorations to understand the differential impacts that distinct breathing techniques can have on mood and respiratory function.
REPRINTS & OTHER CORRESPONDENCE:
David Spiegel, Department of Psychiatry & Behavioral Sciences, School of Medicine, Stanford University, Stanford, CA 94305; & USA Center for Stress and Health, School of Medicine, Stanford University, Stanford, CA 94305, USA firstname.lastname@example.org
Ken Pope, Nayeli Y. Chavez-Dueñas, Hector Y. Adames, Janet L. Sonne, and Beverly A. Greene
Hector Y. Adames, Nayeli Y. Chavez-Dueñas, Melba J.T. Vasquez, & Ken Pope:
Ken Pope, Melba J.T. Vasquez, Nayeli Y. Chavez-Dueñas, & Hector Y. Adames:
“What can we do but keep on breathing in and out, modest and willing, and in our places?”