Al sent me this one to the utimate list. I figured I'd post it to go along with the hyponatremia article I posted awhile back. It's a guide to staying hydrated for those of us who actually exercise.
Dehydration and Athletic Activity
by Dr. Terrence J. Murphy, A.A.S., B.S., D.C.
(text in the extended entry)
Water makes up approximately 50% of our body weight and most of that is in your blood stream. It is through this water that we sweat. Sweat consists almost primarily of water with a small amounts of sodium and other trace minerals. We sweat to cool our body and thereby cool our blood. If your blood temp rises too high it can lead to brain and other organ damage. This rise in blood temp affects the brain and causes such symptoms as confusion/disorientation, hot/dry/red skin (face), vomiting, and passing out. These are the primary symptoms of heat related brain injury due directly to lack of water in the blood stream. Even minor losses of fluid from the blood can severely effect an athletes
performance. An athlete can lose 10% in their performance by losing as little as 2% of their body weight during a tournament. It is imperative that athletes stay hydrated during competition. If you are feeling thirsty it is too late for hydration. You are already in a state of dehydration because the of brain response to the current blood water level. Which means your blood level of water has dropped below acceptable levels. You now need to play catch up in your water dehydration.
The average person needs to take in a minimum of 3 quarts or 96 oz. of water per day just to maintain their current level of hydration. That amount needs to be increased if the person is involved in any kind of athletic activity and even more if the activity is done in hot conditions. Starting out hydrated and not becoming dehydrated is the key good athletic performance. Here are a few tips to preventing dehydration during exercise:
- For every 15-20 min of exercise you must drink 8 oz of water. Even if you are not thirsty. Double that amount if it is in hot conditions.
The key to good athletic performance is keeping your body in proper working order. Adequate hydration is essential to any athletes success. So drink your water before you get thirsty to prevent decreased athletic performance.
Posted by kwc at November 8, 2003 10:14 PM