eli5: why do most, if not all, breathing techniques specify ‘out through the mouth’?

Question

i can understand in ‘through the nose’, since dust and other bits can be blocked by the nose hairs and mucus, and apparently the air is more likely to warm up when passing through the nose first, reducing irritation of the throat.

but what difference, if any, does exhaling through the mouth make?

In: 676

Answer 1

There’s a great Huberman Lab podcast about various breathing techniques to achieve different physiological changes. I can’t remember but it has to do with the speed one breathes in vs. out. And that has a certain effect on your sympathetic nervous system, and thus impacts things like your stress/anxiety levels, heart rate, alertness level, etc.