[pct-l] Hyponatremia

[dude at fastmail.ca (dude)]

rick - the indications you mention are consistent with hyponatremia:
- light headedness
- dizziness
- vertigo
- feeling bloated (lots of water in the belly)
- muscle cramping

Another indicator that I look at quite a bit is swelling in the hands 
and feet.  when you retain water because your electrolytes are all 
screwed up, water stays in your extremities too and they swell.  If I 
feel my wedding ring get really tight, then I know I need to start 
paying attention to electrolytes.  

One thing that is a little counter-intuitive and perplexing is that 
when you drink too much water, you actually stop urinating.  No one 
really is certain why this is, but it does happen.  It happened to me 
in my first 50 miler.  The common accepted wisdom is that if you stop 
peeing, then you are *dehydrated*, which can be true, but can also be 
an indicator for **hyponatremia**.  In my first 50 miler, it took me 11 
hrs, and I didn't stop to pee one time, despite the fact that I drank 
at least 5 liters of water.  To give you an idea how much water that 
is, 5 liters of water would weigh about 11 lbs.  

Like I said, it seems counter-intuitive that drinking TOO MUCH water 
would make you stop peeing, but its true, so watch out for this.  
Nothing could be worse than thinking you were dehydrated when you were 
actually hyponatremic and drinking tons more water when you really 
needed to consume copious amounts of salt and stop drinking water.  

The only realy "cure" for hyponatremia is to stop exercising and rest 
in relative comfort in the shade or air-conditioning.  After I did 
finished the 50 miler and went to my hotel room to sleep, I got up 
about every hour to pee.  After reading several accounts of 
hyponutremia, this is apperently quite common.For whatever reason, your 
kidneys stop p[rocessing water/sodium efficiently until you stop and 
rest.  When they finally kick back in, they start working over-time and 
you make up for all the time that you didn't pee a drop.

there is LOTS of good info out there if you look for it.  the endurance 
cycling community has done lots of research on this topic, so looking 
in those communities may be fruitful, if you need more info.

peace,
dude

_________________________________________________________________
    http://fastmail.ca/ - Fast Secure Web Email for Canadians