Box breathing: from tradition to tactical teams

A square with four counts

You breathe in, hold with air, breathe out and hold on empty, and every phase lasts the same. In Box breathing 4-4-4-4 on this site, that's 4 seconds a side, all through the nose.

It goes by many names: square breathing, 4x4 breathing, four-square breathing, tactical or combat breathing. That variety already tells you something about its history. It doesn't have one origin, but several paths that arrived at the same shape.

The idea comes from yoga

Cleveland Clinic describes it as a form of yogic breathing, born of pranayama, and gives it as a synonym for sama vritti pranayama, breathing in equal phases. Its list of other names includes equal breathing and four-square breathing.

The kinship is clear: pranayama counts the phases of the breath and keeps ratios among them. What's missing is an old text that describes the box as it's taught today, with its four sides of four. Here, Equal breathing (sama vritti) is practiced with no holds, just an inhale and an exhale of the same length.

So calling box breathing an ancient technique goes further than the sources do. It's fairer to say its structure is inherited.

Tactical breathing

In American police and military circles, the same count is known as combat breathing or tactical breathing. The person most often credited with spreading it is Dave Grossman, a retired Army lieutenant colonel, who published the book On Combat in 2004 with Loren W. Christensen.

A 2017 article in Police magazine, written by a sergeant with 17 years on a SWAT team, says Grossman had been teaching it for many years in his seminars, with the count 4, 4, 4, 4. A 2024 academic paper on police training says much the same in other words: the technique was popularized by Grossman, and its use is known mainly through the accounts of military personnel.

That last part matters. What holds up its reputation is the experience of people who used it in hard situations, not a body of research. We didn't find an official military document that describes it.

Mark Divine and the name

The name box breathing is tied to Mark Divine, a retired Navy SEAL commander and the founder of SEALFIT. Police magazine credits him with naming it.

In a piece he published in TIME in 2016, Divine says he first learned to control his breathing while practicing martial arts during his SEAL training. He doesn't say the technique came out of a Navy manual. His version starts by emptying the lungs and holding on empty, then follows the same box through the nose.

Divine describes it as a neutral ratio, one that neither revs you up nor makes you sleepy. That's his experience, told by someone who practices and teaches it.

What the studies say

There aren't many. A 2021 German study compared tactical breathing with prolonged exhalation in 30 healthy people, a mix of officer cadets and civilian students, during an attention task with noise and time pressure. With tactical breathing, the body was less aroused. With the long exhale, performance was better. There was no difference in how people felt. The 2024 paper on police training rates the evidence for tactical breathing as weak.

In the 2023 Stanford trial, 21 of the 108 participants did box breathing five minutes a day for 28 days. Their positive mood went up, but the difference from meditation wasn't statistically significant. The sides ran from 3 to 10 seconds depending on the person.

In 2025, a study of 84 college students found that breathing at six breaths a minute raised heart rate variability more than box breathing did, and that none of the patterns tested changed mood in any meaningful way in a single session.

What isn't known

• Who drew the box first. Nobody has a date or a name. Grossman and Divine spread it; none of the sources we read says either one invented it.
• How it got from yoga to the barracks. Divine points to martial arts. For the rest, we found no documents.
• Whether it pays off under real pressure. The only study that tested it during a demanding task found better performance with a different breathing pattern.

If you want to try it

Start at a calm moment, sitting down, with the 4-second box for 4 minutes. If the hold on empty bothers you, Triangle breathing 4-4-4 leaves it out. Once the 4-second version feels easy, Slow box 5-5-5-5 stretches each side by a second.

The holds should take no effort. If you feel dizzy, tingly or short of breath, drop the pattern and breathe normally. Never do it in water or while driving. If you're pregnant or have a heart, lung or blood pressure condition, check with your care provider first.