Dar tabiat hamai mavjudot nafas mekashand. Dar badani inson zakhirakhoi oksigen mavjud nest, baroi hamin vay be havo zindagi karda nametavonad. Hangomi nafaskashi ba badani inson oksigen dokhil meshavad. Hangomi nafasbarori az on gazi karbon berun meshavad. Mashgul shudan bo mashqhoi jismoni va varzish faoliyati shushro khub gardoni- da, badanro …

Inson be khurok ziyoda az yak mokh zindagi karda metavonad, ammo be ob boshad, hamagi yakchand ruz. Hangomi ijroi mashqhoi jismoni, sayru sayohat koidakhoi obnushi Hangomi mashq kardan (alalkhusus dar havoi garm) ob nushidan mumkin nest. Pas az 20-30 daqiqai mashq boshad, nushidani sharbati meva yo sabzavot, nushokiho, obi minerali …