I think it means that they are pushing water away or something, because they are too lazy to move. I can't remember what this achieves but it does something.
Although, I could be entirely wrong.
They take breaths through going up to the surface and gulping it, or through the "fluffy" bits - this is the part where a gas exchange occurs (or something like that) but this happens without them moving their gills.
Wait for a better answer, though.