Background
Breathwork may be defined as deliberate control of breath rhythm and pattern, usually with the aim of increasing focus and relaxation and/or with the aim of influencing emotional, mental and physical healthFast forward to the present and breathwork has transformed and extended its reach to use and teaching by modern-day psychedelic groups, medical professionals, elite performers, military, along with practitioners of health and wellness more broadly. Public interest in breathwork has exploded due to its therapeutic potential, but it is essential such excitement is grounded in a robust evidence-baseSlow-paced breathwork has received most research attention thus far, and its physiological effects have been detailed extensivelyThere is one particular rhythm of breathing (5–6 breath cycles per minute—bcpm—with no deliberate pauses) that is widely found in religions and cultures around the world (in Yoga, Qigong, prayer and mantra, along with meditation) and has been researched in scientific practiceResearch to date examining the efficacy of CB in improving mental health lacks internal validity as control conditions do not allow effects to be attributed to CB with confidence