Breathwork glossary — key terms, explained simply

Core terms

Autonomic nervous system (ANS)

The branch of the nervous system that regulates involuntary functions — heart rate, digestion, breathing, immune response — without conscious input. It has two main branches: the sympathetic (activating) and the parasympathetic (calming). Polyvagal theory adds a third functional state: the dorsal vagal shutdown state.

Box breathing

A structured breathing technique with four equal phases: inhale, hold, exhale, hold — each for the same number of counts (typically four). The symmetry creates predictability and is particularly grounding for dysregulated nervous systems. See box breathing for fearful-avoidant grounding.

Coherent breathing / resonant breathing

Breathing at approximately six breaths per minute (about five seconds in, five seconds out), which research has shown maximises heart rate variability and activates the parasympathetic nervous system. Also called resonance frequency breathing.

Conscious connected breathwork

An umbrella term for breathwork practices using a circular breathing pattern — no pause between inhale and exhale — sustained over an extended period (typically 45–90 minutes). Includes Holotropic Breathwork, Rebirthing, Clarity Breathwork, Transformational Breath, and others. Requires a skilled facilitator and appropriate health screening.

Diaphragmatic breathing / belly breathing

Breathing that engages the diaphragm — the dome-shaped muscle beneath the lungs — rather than relying primarily on the chest. Produces slower, deeper breaths and activates the parasympathetic nervous system more effectively than chest breathing.

Dorsal vagal state

In polyvagal theory, the evolutionarily oldest state of the autonomic nervous system — associated with immobilisation, shutdown, numbness, and disconnection. Often present in avoidant attachment patterns and freeze responses.

Extended exhale

A breathing practice in which the exhale is made longer than the inhale (typically in a 1:2 ratio — e.g., inhale four counts, exhale eight counts). Directly activates the parasympathetic nervous system and is one of the most accessible and evidence-supported calming practices.

Physiology and measurement

Heart rate variability (HRV)

The natural variation in the time between heartbeats. Higher HRV is associated with greater nervous system flexibility, better emotional regulation, and more resilience to stress. A key measure of the effects of breathwork practice.

Holotropic Breathwork

The conscious connected breathwork method developed by Stanislav and Christina Grof in the 1970s. Uses extended connected breathing, evocative music, and bodywork to access non-ordinary states of consciousness for therapeutic purposes.

Interoception

The capacity to sense and feel the body from the inside — heartbeat, breath, gut sensations, physical tension, emotional signals as physical experience. A core skill developed through breathwork practice and often reduced in avoidant attachment patterns.

Parasympathetic nervous system

The branch of the autonomic nervous system associated with rest, digestion, repair, and social connection. Often called the "rest and digest" system. Activated by slow, rhythmic breathing — particularly by extended exhales.

Physiological sigh

A naturally occurring double inhale followed by a long exhale, which re-inflates collapsed air sacs in the lungs and produces rapid nervous system calming. Can be used deliberately as a quick regulation tool.

Polyvagal theory

The framework developed by neuroscientist Stephen Porges describing three states of the autonomic nervous system (ventral vagal, sympathetic, dorsal vagal), their relationship to felt safety and threat, and the role of the vagus nerve in regulating social engagement and connection.

Pranayama

The yogic tradition of breath regulation, developed over thousands of years and encompassing a wide range of breathing practices used for health, mental regulation, and spiritual development.

Sympathetic nervous system

The branch of the autonomic nervous system associated with the fight-or-flight response — mobilisation, increased heart rate, fast shallow breathing, readiness for action. Chronically activated in many anxious attachment patterns.

Vagus nerve

The longest cranial nerve, running from the brainstem through the neck and into the chest and abdomen, connecting the brain to the heart, lungs, and gut. Central to polyvagal theory and to the mechanism by which breathwork influences the nervous system.

Vagal tone

A measure of the activity of the vagus nerve and the parasympathetic nervous system. Higher vagal tone is associated with greater emotional regulation, more capacity for social connection, and better stress resilience. Regular slow breathwork increases vagal tone over time.

Ventral vagal state

In polyvagal theory, the state associated with felt safety, social engagement, and connection. Characterised by a regulated heart rate, warm and expressive facial engagement, and full rhythmic breathing. The physiological home of secure attachment.

Window of tolerance

The optimal zone of nervous system activation — not too activated (sympathetic dominance) and not too shut down (dorsal vagal) — in which a person can process experience effectively and remain present. Developed by psychiatrist Daniel Siegel. Breathwork practice can widen the window of tolerance over time. See window of tolerance and the breath.