Hydration 101

What Every Runner Should Know About Hydration
Surely we all know that hydration is important to our health and performance. Most of us have been drilled to believe that 8 glasses of water a day is the way. Many of us even know that the human body is made up of about 66 percent water. That's two-thirds of our mass that depends on us being properly hydrated.

Some other facts about our body's need for water include:
Our bones are 22 percent water.
Our muscles are 75 percent water.
Our blood is 83 percent water.
Our lungs are 93 percent water.
Our brains are 95 percent water.

No wonder we get dizzy, listless, and unfocused as we get dehydrated. Our brain is almost entirely made of water. So, when it starts getting low on water, it can't function at full potential. Other signs of dehydration include:
dry, itchy skin
headaches
thirst
fatigue
crankiness
becoming stressed easily
unclear thinking
flushed face
cramping
weakness
sleepinees
dry mouth
bloating
constipation

Water is also the force behind temperature control for our bodies.
We sweat to help regulate our body temperature. If we can't sweat (for lack of water), our body temperature spirals up and we quickly find ourselves at risk for heat injuries, like heat cramps, heat stroke, and exhaustion. (Heat stroke is, by the way, deadly. These are not just run-of-the-mill, I'll-feel-better-in-a-day-or-two type problems. These injuries are serious, and should not be taken lightly.)

So, how do we know how much to drink to maintain proper hydration? Thankfully, under normal living conditions, we simply need to drink when we are thirsty. That is what our thirst mechanism is for, after all. However, I know from personal experience that many of us don’t take the time to drink when we are thirsty. Whether you are too busy in your office to get up and get a drink or just don’t have a way to get water when you are out and about, if you don’t carry water with you regularly, you may learn to ignore your thirst mechanism. Or, perhaps you are just very goal-oriented (as we runners tend to be) and would like to have a number to shoot for. In these cases, it can be helpful to have an idea of how much water you should be consuming in a day.

Common knowledge suggests that the least amount of water that most healthy adults should consume (to maintain hydration) everyday is 8 to 10 cups (8 oz). But the Institute of Medicine advises women to drink about 74 oz (9 cups) and men to drink about 101 oz (13 cups). You should remember that this is just a guideline. The Institute of Medicine also mentions (as I have also stated above) that “the vast majority of healthy people adequately meet their daily hydration needs by letting thirst be their guide.”
Hydration is that simple. So, as Nike would say, just do it!