You are literally stretching out your lungs so that they can hold more air. The average human female has a capacity of four liters, and the average male six liters. Endurance training can increase those numbers, but only slightly. Lung packing, however, can add up to three liters to a person's lungs.One diver named Herbert Nitsch even has a reported 14-liter capacity.yclist Miguel Indurain has massive lungs for a non-diver (8 liters), and they were reportedly large enough to displace his stomach, which gave him a trademark paunch. Chances are you won't need to hold your breath for 20 minutes in your lifetime, or even 5 minutes.