[superhornet59]

is this independant of speed of assent? i would think if you go up fast (monofin especialy) itll be more likely. also at like 300 feet a divers lungs become smaller then the volume of air in your mask, if you use fluid goggles can you possibly go longer due to double the air volume in your lungs at that depth (not all will be oxygen, but its still precious meters) and are there any exercises i can do to prevent injury from lung shrinking and to increase the stenght of the dive relfex?