Don't feed the troll, guys. Either this guy is just playing with you, or he probably also believes the earth is flat or something. There are few things so well scientifically explored as the plethora of different negative consequences of smoking, so if he would be interested in realistic insights, he would stumble across studies and answers everywhere himself easily, so that is definitely not the case. Also, there are plenty of longterm extremely harmful drugs that might even increase ones performance short term, so this runner obviously didn't prove anything to anyone.