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

If you exhale and inhale through the same hole you disturb the flow. Sometimes with stagnant air sometimes with body fluids. Since you have two air holes they assign one task to each so you can be as focused as possible.

The noise filters and warms so it gets the in job.

The mouth has a greater capacity so it gets the out job.