Box Breathing

Equal inhale, hold, exhale, hold

Inhale Hold Exhale Hold

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Why it works

The Science of Box Breathing

Box breathing (also called square breathing) activates your parasympathetic nervous system — the “rest and digest” mode that counteracts stress.

The equal intervals create a rhythm that slows your heart rate and signals safety to your brain. The breath holds temporarily increase CO&sub2;, which paradoxically helps you feel calmer by dilating blood vessels and improving oxygen delivery.

This technique is used by Navy SEALs, first responders, and athletes to maintain calm under pressure. Regular practice can lower baseline cortisol levels and improve heart rate variability (HRV), a key marker of stress resilience.

Research: Ma et al. (2017), Frontiers in Psychology; Zaccaro et al. (2018), Frontiers in Human Neuroscience