Nasal breathing

Breathing through the nose, which filters, warms, and humidifies air. It also supports nitric-oxide availability and is commonly preferred during rest and low-intensity activity. The nose also adds gentle resistance, which tends to slow the breath and encourage use of the diaphragm. Many breath trainers recommend nasal breathing during sleep and light exercise and switching to the mouth only when the body needs more air. If the nose is often blocked, a doctor can check for causes such as allergies or a deviated septum.