I'm the perfect answer to your question!
I smoked 4 or 5 cigs per week, hardly a lot.. but still enough to build up noticable amount on my lungs over the last 5 years.
I am a personal trainer, I can run a mile in ~6 minutes on average, (my best is 5:39), but im also 210 lbs and 5'8 - so i'm not built like a runner
since switching to a vape, while i havent increased my time by anything significant (a few seconds faster on average, but that can be from sleeping better among many other factors) but after my mile my chest is not as tight and breathing isn't as pained. I have been coughing a little bit, but that just means that my body is cleaning out the tar buildup because i haven't been contributing to it.
Keep in mind, i'm smoking non-nicotine cartidges, but i am also vaping about 10 times as much as i used to smoke (about 5-6 cigs per day worth) because it's so much fun, and doesn't hurt my lungs.
I can easily say if i increased my analogue intake 10 times, i'd feel sick and horrible right now.. not increasing my mile times