‘Runfluencers’ Want you to Breathe Through Your Nose, but Here’s What the Science Says

Running is more popular than ever, and with an influx of new runners comes an influx of influencers offering up their advice—some of it helpful, some of it distinctly not. If you’ve spent any time scrolling through running-related videos, you’ve probably stumbled across a coach, athlete, or “runfluencer” insisting that you shut your mouth when you run. The advice to breathe through your nose while running is nothing new, but is it actually backed by science?

The answer, as with most things in running, is nuanced. Here’s what the different schools of thought say, and how to actually put better breathing into practice on your next run.

Should you really breathe through your nose during cardio?

I personally noticed nose-breathing having a cultural moment online back in 2020, thanks to the popularity of James Nestor’s book Breath. My BookTok and RunTok feeds combined forces, with creators latching onto the idea that modern humans have forgotten how to breathe correctly, and that we should be breathing through our noses most of the time.

Whether or not you buy that exact claim, studies do show there are merits to nasal breathing during cardio. When you mouth-breathe heavily, you exhale carbon dioxide too quickly, which can trigger that frantic mid-run “can’t catch my breath” feeling. Nose breathing naturally slows your breathing rate and helps your body tolerate CO2 better over time. If nothing else, it’s a great way to pace yourself and stay in the coveted Zone 2 (the low-intensity aerobic range that builds your aerobic base and is currently having a major moment).

At the same time, mouth breathing is a completely natural and necessary adaptation at higher intensities, and trying to suppress it can hurt your performance. There’s a simple reality at work here: Your nose has a much smaller airway than your mouth. At easy, conversational running paces, nose breathing is entirely manageable. But once your heart rate climbs into higher intensities—tempo runs, intervals, or race pace—your muscles demand more oxygen than your nose can quickly supply. Forcing yourself to breathe only through your nose while running at high intensity can make hard workouts feel unnecessarily brutal.

For most of us, a hybrid approach makes sense: nose breathe on easy and long runs to build aerobic efficiency, and let your mouth open naturally when the intensity demands it.

When to inhale and exhale on your runs

Some runners don’t take a strong stance on nose versus mouth breathing, and instead focus more on the timing of breaths relative to movement. This focus is called “rhythmic breathing,” where you time your inhales and exhales with your footstrike. The thinking is if you always exhale on the same foot—say, every time your right foot lands—you’re repeatedly loading one side of your body at the moment of maximum stress, and that over miles and miles, that asymmetry adds up.

One solution is to breathe on an odd-count pattern. For easy runs, a 3:2 ratio works well—inhale for three steps, exhale for two. For harder efforts, a 2:1 ratio (inhale for two steps, exhale for one) keeps oxygen flowing without disrupting your rhythm. Because you’re working on odd counts, your exhales naturally alternate between your left and right foot.

How to breathe better during your runs

Here are some ways to practice breath control during your next workout.

• On your easy runs, commit to nose breathing only. You might discover you’ve been running easy days far too fast once you can’t cheat with your mouth open. If you can’t maintain nasal breathing at an “easy” pace, you’re going too hard.

• Try the 3:2 rhythm on a relaxed run. Inhale through your nose for three footstrikes, exhale through your nose (or mouth) for two. Some runners find this meditative; others find it distracting at first. Either way, I find that the awareness it builds is valuable.

• Learn how to do a quick body scan. Are your shoulders hunched up near your ears? Is your jaw clenched? Are you taking rapid, shallow breaths? Drop your shoulders, unclench your jaw, and take one long, slow breath to reset. Tension is the enemy of good breathing mechanics.

• Cool down with intentional nose breathing. The last five minutes of your run are the perfect time to return to deliberate nasal breathing.

Remember, you can open your mouth when the intensity demands it. The goal isn’t to be a nose-breathing purist at all costs, but to recalibrate your breathing to make your runs feel easier. If you’re looking for ways to practice, I recommend trying the Nike Run Club app‘s guided runs with breathwork coaching cues, as well as any built-in breathwork activities you can find on your running watch (I use some on my own Garmin).

The bottom line

This time, the influencer-driven buzz isn’t entirely social media noise. There’s real science behind the nose breathing push, and the habits it encourages—slowing down, building aerobic base, becoming more body-aware—are important for runners at every level. But for me, nose breathing is not a religion. The best breathing strategy is the one you’ll actually practice consistently, and which helps you stick to your running routine.