Smoking and cycling

Let me first of all say that i am not a smoker and the only reason i ask this is because of the 100+ cigarette per week habit of my ex girlfriend. I noticed that as i was in attendance for nearly all of her daily puffs it did seem to have a negative effect on how i felt when riding my bike as i tended to have to cough up a lot of mucus like material which i never used to have to do at all.
There may be no connection between the two at all as i have only recently recovered form a cold which may have played a part in creating the mucus but what surprised me was that the time it took for me to complete my ride, which is always the same distance, actually decreased which suggest that the effects, if any, of the passive smoking were not all detrimental.
Also if anyone can give me a time frame on how long it may take my body to recover from the effects of the smoke i have inhaled (i was only with her for a month) i would be really grateful as i'd love to know when i will fell as i used to when pushing the pedals.