Your body consists of up to 60% water. Amazingly, the lung, responsible for air exchange, contains more than 80%. Each cell wraps around a blob of liquid teaming with functional components, each cells bathes in interstitial fluid, the brain and spine immerse the nervous system in cerebrospinal fluid.
Last, but not least, about 6-7 litres of blood circulate through one of the plumbing networks, which is about 100,000 km in length. The heart generates a vortex, pulling blood through its outlets. Expansion and contraction of blood vessels and connective tissue maintain the standing wave generated by the heart beat and regulate the amount of blood reaching different areas of your body.
Blood carries oxygen, the main fuel for your metabolism, but also hormones, nutrients, viruses. Roughly 3 litres of plasma facilitate the movement of blood cells and other bits, and also the exchange of chemical composites throughout the entire tissue.
Your inner liquidness, combined with some air in your lungs, allows the body to float on water. It even lets the bones float in the mesh of connective tissue, muscles, tendons and ligaments. When the flow on the inside gets interrupted, your movement will get less fluid as well.
The plumbing system organises the majority of the physiological components of the body, serving a variety of functions. Each of this aspects deserves a closer look, but as the system organises itself to a large degree, it takes little effort to keep it running.
Keep hydrated. The sensation of thirst warns the operator of a body (you) about the need for rehydration. Try to avoid this. Try to avoid drinking too much, either.
Avoid blood loss.
Move your body on a regular basis.