ELi5: Why is it often recommended to breathe in through your nose and out through your mouth?

Question

ELi5: Why is it often recommended to breathe in through your nose and out through your mouth?

In: Biology

Answer 1

Breathing nasally in general has already been covered, but it’s also important for a different reason during exercise. Nasal inhalation during exercise helps you control the speed and depth of your breathing, in order to avoid hyperventilating or not getting enough oxygen during aerobic activities like sprinting or biking.

Also, if you have exercise-induced asthma, nasal breathing can reduce your risk of setting off a flare-up by warming and moistening the air before it hits your lungs, which limits the irritation caused by huffing and puffing dry air through the mouth.