Exercise makes muscles and or fitness systems more efficient and more effective.
So if you were to undertake exercise that worked the predominant muscles of the respiratory system, - namely the diaphragm and the intercostals- , then you would enable those muscles to take in and expel greater volumes of air in a given time.
The exercise required would have to involve these muscles working through a full range of motion (Deep / heavy breathing) for a minimum amount of time (20 minutes).