So I started running again. I can say from experience that vaping has to be better for your lungs than smoking ! I was up to running 5 or more miles a day and up to 10 miles while smoking a pack a day. (I'm a former Marine so I tend to do things to the extreme.) When I was smoking in the beginning of a run I would feel a tightness in my chest and I used to attribute to having to get into an aerobic heartbeat. Breathing would be hard for a while. But I would always push myself to do the run. I would finish a run and stop and hack a bit then light a ciggarette. (..... I am lol) I always wondered how it would feel to run if I wasn't smoking. So I haven't run in quite some time (Old Man Winter) and I have been quit smoking for a while. So I started out with a short 2 mile run today. Guess what ? No tightness in the chest, no hard breathing and no hacking ! Can't wait to get back up into the big mile range again ! So if vaping actually had an effect on your lungs would I have not felt it ? In contrary vaping has greatly improved my lungs. So I don't need any scientific studies I just completed my own study ! Hey if anyone else has noticed the same thing let me know I'm interested in your opinion.