wow what the f*ck? are you kidding? were you sleeping in health ed?
it's not the nicotine in cigarettes it's the tobacco that slows your heart down and puts more pressure on your arteries and heart so it makes it harder to exercise/run. same goes for weed. but i used to smoke weed but not cigarettes and when i tried to run, it would have pressure on my heart and it would make me quit fast. but when i stopped smoking weed and took up running again, i felt like a damn robot and had no problems in my heart.
so cut the weed and the cigarettes, there's a reason why people die so young from that cr@p