smoking hardens the arteries and capillaries(SP?) which definitely affects blood flow, which will definitely inhibit muscle growth and recovery. For about and hour or two(I think) after a cigarette capillaries constrict, decreasing blood flow. So, a cigarette after lifting means less nutrients from that post-workout shake are getting to your muscles. And all day long when you smoke, like, say, right after you eat? sounds like a big hindrence to growth to me.
Oh, and on a side note, the whole,“Well I’ve been making good gains anyway so it’s all right” arguement drive me crazy, because they have no idea what kinds of gains that they could’ve been making if they didn’t have whtever bad habit they’re defending.
The above rant is not directed at you, I’ve just gotten it too many times from friends/aquaintances. Mostly about smoking.