Fitness instructors, you may have noticed, are always nattering on about breathing: "Breathe through the nose," "Control the breath," "Push up on the exhale."
There's a reason for that.
"Your breathing matches the level of activity," said David Hryvniak, a physical rehabilitation and medicine fellow at the University of Virginia Health System and team physician for several of the school's sports teams. "If you run and jump, you will breathe through both your mouth and nose to get the proper amount to oxygenate the body."
This is not just a matter of getting enough oxygen to the lungs and other organs; oxygenating the body, in addition to things like carbohydrates, supplies a building block to the muscle cells to create energy to refuel the muscles.
"But if you are relaxing and really taking those deep belly breaths, then you can breathe through the nose," said Hryvniak, who also is a long-distance runner.
In fact, breathing deeply and fully can be key when relaxing and releasing tension, said psychotherapist Elliot Greene.
"Humans don't tolerate anxiety very well," said Greene, who specializes in the interconnectedness of the mind and body and uses massage therapy in his practice. "One of the ways we cope is to shut down."
That means "putting a lid on" or "choking on" our feelings — both apt expressions since they can involve partly holding our breath, tensing the diaphragm and relying on shallow breathing, Greene said.
When we do all this, it has ripple effects throughout the body and mind, Greene said. Our shoulders hike up, and our throats constrict — we feel stuck physically and mentally, hardly a relaxed state.
On the flip side, if we breathe deeply and can release some of the builtup tension — physical and emotional — we feel better, Greene said.
"Taking deep chest and belly breaths can help us become 'unstuck,' " he said.
From an athletic standpoint, Hryvniak said, belly breathing is recommended because the abdominal muscles are stronger than the diaphragm and can help supply the body with oxygen more efficiently if they are engaged.
"We preach belly breathing" to our athletes, Hryvniak said, adding that breathing is part of athletic conditioning these days.
Learning how to be aware and eventually to control our breathing, Bikram yoga instructor Lara Atella said, can help slow down the heart rate and inhibit the release of adrenaline and cortisol — stress hormones that can age us prematurely.
In essence, the breath not only helps us get the most out of the physical practice — whether it's yoga or running — but also helps shape up our insides.
"We tone our nervous system by how we breathe," said Atella, who has a background in neurobehavioral science at Johns Hopkins University.
One way to start becoming more aware of breath is to make a slight oceanlike sound in the throat, making the breath a more tangible focal point.
"Natural deep breathing is like a wave," Greene said. "You focus on the exhale, and then the in-breath rushes in."
For athletes, though, the in-breath and the out-breath are not necessarily the same length or quite as instinctive as Greene describes.
Instead, for University of Virginia runners, Hryvniak recommends breathing in for two strides and breathing out for one stride — a "two-to-one pattern," he calls it.
Seem like a lot to coordinate?
"I recommend starting with easy runs where it is easier to control the breath," he said. "You slowly introduce the pattern, and then it becomes routine."
For weight lifters and other power athletes, breath plays an important role, too. If they hold their breath, which can happen, they risk building up too much pressure in the chest cavity, Hryvniak said. This can lead to everything from hernias to, in rare cases, heart attacks.
"We recommend that you breathe deeply throughout the entire rep," Hryvniak said. Usually, the push or top exertion happens on the exhale.
To recap: Breathe through the nose for calm and focus; through the mouth and nose for high energy; let the breath flow to avoid chest cavity pressure; and use deep belly breath for effective oxygenation and mental release.
Gabriella Boston is a fitness trainer and freelance writer.