Obviously, running is good for your lungs. As long as you give your lungs some adequate exercise. I find that I consistently need to exercise my cardiovascular and respiratory system to keep my lungs in shape. If I ever say, skip too many days of this exercise, an accumulation of some sort occurs (mucus), I experience sclerodermic like effects of the lungs, and an overall decrease in lung stamina. Btw, I abstain from tabacco. The smell gives me headaches.