Re: Sodium homeostasis... was Re: tears

Tom Clarke (clarke@longwood.cs.ucf.edu)
7 Nov 1995 09:28:10 -0500

sstinson@uoguelph.ca (Sean Stinson) writes:

>pete (VINCENT@REG.TRIUMF.CA) wrote:

>: Thus the advent of electrolytically balanced drinks for athletes.

>Sean replied,
> ...which have been shown to be mostly a marketing
>scam (nice reference!). Electrolyte balanced drinks are
>only rarely needed. Marathon runners, triathaletes,...
>but these people are all fucked up anyways, half the women
>don't even menstruate! Most athletes DO NOT require
>electrolyte balanced drinks. Sweating cuases an increased
>concentration of sodium, potassium, chloride and calcium in
>the body fluids, not a decrease.

You must have missed my posting about the story of GatorAde (tm).
You are right, if you sweat, the conc of salt etc in your
fluids increases, even though the total amount of salt in your
body decreases (sweat is salty). However, if you replace
the water, as you must, then the result is body fluids with
less sodium since sodium has been lost in the sweat.
This is simple conservation.

Dr. McCade (Urologist, U of Fl) found that football players
after 3 hours in the heat of the stadium (Florida field is
_very_ hot) had really screwed up electrolytes. When he
fed the freshmen squad his concoction of salt, glucose and
lemon juice (attempt to make it palatable - "Doc, this
stuff tastes like piss") the varsity second squad beat
them, as usual, during the first half of a practice game.
During the second half, however, the freshman beat the
varsity ("Doc, this stuff still tastes like piss, but good piss").

I was a long time GatorAde skeptic, but this summer I tried
some on one of my woodworking sessions outside in the 90ish
FLorida heat instead of my usual iced tea. Admittedly,
anecdotal, but I did not have the usual flag in energy
after a couple or three hours of sweating in the heat.

Admittedly, really balanced drinks, those with more than
just the basic salt and glucose (for energy), are probably
marketing hype, a little potassium costs nothing, but gives
a marketing handle. But I think the basic sport drinks do
have value. Hell, when I was a boyscout they used to give
us salt tablets in the heat.

> Sweating is NOT a method
>of electrolytes excretion. The kidneys ARE. Look to urine
>for electrolyte excretion not tears or sweat.

Yes, the purpose of sweating is not electrolyte excretion. But
you can die if the salt lost through sweating is not replaced.

Tom Clarke

-- 

  People of the same trade seldom meet together, even for merriment

  and diversion, but the conversation ends in a conspiracy against

  the public, or in some contrivance to raise prices - Adam Smith, WofN