Breathing is supposed to be natural. We start as we leave the womb and we spend the rest of our years inhaling and exhaling, until our lives end.

But what if breathing correctly isn’t that easy and doesn’t come naturally?

And what if athletes, those whose performance depends on their ability to breathe, aren’t even that good at it?

A new study by a team of Japanese researchers studied nearly 2,000 athletes from different age groups and sports looking for dysfunctional and diaphragmatic breathing patterns.

Diaphragmatic breathing is good. It’s associated with nice posture, core stability and reduced injury, pain and stress. It happens when one’s breathing produces a rhythmic, visible movement of the upper and lower rib cage and abdomen.

By contrast, those with dysfunctional breathing patterns don’t contract their diaphragm as they should and other muscles pick up the slack. Their rib cage and shoulders tend to move up and down as they breathe and their abdomens don’t move as they should.

The scientists found that 91% of the athletes were dysfunctional breathers, while just 9% were deemed diaphragmatic breathers.

They found that baseball players were better at breathing than those who played basketball, tennis, badminton or volleyball.

And they noted that the highest proportion of dysfunctional breathers were middle school athletes, followed by elementary-age athletes and high school athletes. Collegiate athletes fared a little better.

In short: Learning to hit a curveball or spike a volleyball is great, but athletes — not to mention the rest of us — would benefit far more from a breathing coach.