Maybe you hit the vending machine for the quick sugar-high of a sweetened fruit beverage. So often we take our complex bodies for granted and don't provide the tools needed for them to work efficiently. We tend to think of our fluid intake more in the summer because of the heat.
Water does help our bodies with temperature control.
It also carries nutrients, oxygen, and other important substances around the body for fuel, transports waste products away, lubricates our joints, creates less stress on the kidney to do its job, reduces constipation with the help of fiber, and many other important functions. For all you recreational and more serious athletes, lack of sufficient fluids is the first thing to decrease your performance because physical activity speeds up the need for fuel, removal of wastes, and for temperature control. Maybe you are a little low on fluids, as these are some of the first signs of mild dehydration. We also can not wait until we feel thirsty to drink - by this time, we are often slightly dehydrated. You are the gate-keeper for the types and amounts of fluids you put into your body.