overhydration

I don't even think that is physically possible!  lol

Possible, but very uncommon.  Are you thinking of hyponatremia (low sodium)?  What makes you fearful of that? 

The *only* case I've ever heard of involved a small child and child abuse (she was made to drink way too much water). I suppose it's possible, but your stomach would hurt terribly from all that water! I think you'd have to either drink several gallons in one sitting (ugg!) or drink several liters and not have any salt in your system. I doubt most Americans are at risk from having too little salt. But, if you're still worried, it's a great excuse to have a bag of chips!

My problem is that my stomach can't absorb the water I drink fast enough and yet I still *feel* thirsty. On particularly memorable run a couple of months ago, I was over-dressed for the weather (it was cloudy and cool when I left home, but got sunny and warm when I arrived at the park), and after one lap, I was over-heating. I stopped for water at the fountain and drank and drank and drank some more. When I tried to run again, my poor little stomach was just too overloaded and I felt awful! I read something recently, maybe in another post on this forum, that the body takes 15 minutes to absorb the water we drink. After that run, I can believe it!

Technically, it is possible, but it's not very probable. Not too long ago here in CO, a teenager 'drowned' from drinking too much water; a side effect to taking Ecstacy.

I would think that you'd have more to worry about with cramping (running with too much water in your stomach) and stopping every 5 minutes or so to relieve yourself.

Actually this IS possible (but again, not common)

and what it amounts to is overhydrating without sufficient electorlytes.

So, COGirl, has it on the mark. When you race, when you train for any longer distance--don't just use water for your hydration. Be sure to replace those electrolytes--but even so, most of us our liable to not reach that dangerous point--we'll just get tired and bonk and eventually stop. You basically would have to be a super driven person to push through that kind of depleted energy!!

But even so--replace electrolytes!!

Dana

Good news! It was so hot and humid here this weekend, I drank 2 quarts of water in 2 hours, and got worried that I was drinking too much liquid.

When in training, I would view it as impossible to overhydrate because I sweat it out. But once, while in college, I definitely overhydrated, and I've never been back to that beer hall since!

The real problem is not to much fluid, but not enough sodium or electrolites. You know that salty residue on you running shirt after a long hard run in the heat. That salt is needed to sweat and without it, your body will hold it in. Not a big concern for most people. If you are worried, switch to a sports drink to get your sodium fix.

As others have said, it's more a function of low sodium levels (http://www.rice.edu/~jenky/sports/salt.html) Being a marathoner and just starting into the tri stuff, this has been a big topic of late. It has to more with taking in to much water and diluting the sodium levels in your body. It's especailly worrisome for the slower paced marathoners that are out there for 5+ hours and drinking copious amounts of water at each aid station. The big problem is that the symptoms of hyponatremia mimic those of dehydration (light headedness, confusion, etc...) and it's possible that the treatment could do more harm then good. The best advice is to make sure you take in not only water, but also an elctrolyte replacement during exercise

Check out this link, there is some great information http://www.usatf.org/groups/Coaches/library/hydration/

Overhydration is not a big problem with runners and cyclists especially in the heat of competition. If you happen to drink too much, your body deals with it in the usual manner by reminding you to visit the facilities.

your fear of overhydration is a very serious matter, and it is very possible (and becoming increasingly common recently). At the Boston marathon, a women died of overhydration, also known as, "water intoxication." Essentially, the "back of the packers" who do not sweat as profusely as those hydration recommendations are geared towards, over-hydrate by dilluting their electrolytes within their blood content.