The first compartment that's going to be influenced is the extracellular compartment. Exercise, not drinking, vomiting, diarrhea, sweat loss, even say use of a diuretic. And so all these changes within the scenario that we're going to talk about is going to do two things to the extracelastic fluid. These two things are either you add or remove solutes from the extacellular fluid, or you gain or lose water molecules from that fluid. Now, based on those two things, we'll then determine where the water might shift from the other compartment, which is the intracellular compartment.