Tom, Kudos & Calcium

["Beth Glace" <lb@nismat.org>]

It is important to remember that humans produce a sweat that is 
hypotonic to plasma:  humans produce a sweat that is more dilute 
than blood.  [Horses produce a more concentrated sweat]  So, when 
sweating we are losing more water than electrolytes.  The 
prime concern for a human is getting fluid back, and only if the 
exercise is severe and prolonged is an electrolyte imbalance an 
issue. This is particularly true of sodium.   I've never seen a case 
report or study that showed significant depletions of calcium due to 
exercise.  Since calcium in the blood is strictly regulated by 
parathyroid hormone, the circulating calcium can almost always be 
maintained by "stealing" calcium from the bones.   That is, blood 
calcium is not diet sensitive.  There are no studies that I've seen 
that show muscle fatigue delayed by supplemental calcium.  I'd 
suspect, as Susan says, that the reason for the Tums is to prevent 
stomach upset.  

Beth Glace MS
Sports Nutritionist
Lenox Hill Hospital
NY, NY
>I recently read a tip, in Endurance News I think, to bring Tums 
while >on a ride and for the rider to take one at the stops "for the
>calcium".  I'm ignorant... what does the calcium supplement help?  It
>did not say, in the article.  I take 'em anyway occasionally just for
>standard heartburn, I was just wondering what other purpose they
>serve.
Susan wrote:
Muscle contraction uses up alot of calcium.  In horses when you
deplete too much calcium, you get thumps.  In people, you get tired
muscles and have to work harder to get the same work output.  So
calcium just helps with that. In my case, it also helps the tummy.


=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Ridecamp is a service of Endurance Net, http://www.endurance.net.    
Information, Policy, Disclaimer: http://www.endurance.net/RideCamp   
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=