This includes dilating our pupils, increasing the heart as well as our breathing rate and increasing the mouth that we sweat. So that's because when we sweat we're basically expelling the byproduct our energy. So as we produce more ATP in our muscles, that creates more energy, more thermal energy as a byproduct. And to keep our temperature of the body at the same temperature, we have to expel that energy. And we do that by the process of sweating. Now, when we're running, we don't have to worry about digestion.