Belief in the benefits of controlled breathing goes back centuries.

Central to ancient Hindu philosophy was prana, described as vital “airs” or “energies” flowing through the body. Stemming from that belief, yoga was built on pranayama or breath retention.

In the first half of the 20th century, deep breathing began to emerge on its own as a relaxation method.

Every relaxation, calming, or meditation technique relies on breathing, which may be the lowest common denominator in all the approaches to calming the body and mind.

Breathing is the only autonomic system we can wrest control of.

Controlled breathing techniques can get one autonomic system under control and in turn affect others (like the heartbeat), alleviate momentary anxiety and longer-term emotional stress, and perhaps even improve physical and cognitive health outcomes.

Normal human breathing at rest should raise the belly, not the chest.

To relax during a particularly stressful moment, take three slow, deep belly breaths to interrupt the fight-or-flight response.

• Find a comfortable place to sit or lie down.
• Breathe in through your nose and fill your lungs from the bottom up, first expanding your belly, then your chest, and finally raising the collar bones.
• Pause.
• Then gently exhale from top to bottom, using your stomach muscles to push out the last of the air.
• Pause. Then repeat.