A normal person in good health can hold their breath for up to two minutes when they aren't moving, but if they're actively swimming, they'll need to breathe much more often. You don't hold your breath when on a marathon, after all.
BFHHAA!!Alright~!!I've managed to dive, for 60 seconds!!Oh, Hamakaze! Did you see that!!I can do it too if I try, right!?