Box breathing, also known as four-square breathing, is a powerful physiological reset used by elite performers—including Navy SEALs and athletes—to manage high-stress situations. The technique works by stimulating the vagus nerve, shifting the body from "fight-or-flight" to a "rest-and-digest" state. This transition lowers cortisol, reduces blood pressure, and restores immediate mental clarity.
The beauty of box breathing lies in its rhythmic simplicity. To practice, visualize a square and follow these four equal steps:
Inhale: Breathe in through your nose for a count of 4.
Hold: Retain the air in your lungs for a count of 4.
Exhale: Release the breath slowly through your mouth for a count of 4.
Hold: Keep your lungs empty for a final count of 4.
Progression: As your lung capacity and carbon dioxide tolerance improve, you can challenge your nervous system by increasing the duration. Many practitioners start at 4 seconds and gradually expand the period to 5, 6, or 7 seconds per side. This deeper pacing further slows the heart rate and intensifies the calming effect.