Again I agree that over hydration kills, and the water and Gatorade are roughly equivalent as far as the effect on serum sodium.
It is fairly simple in how we manage serum sodium in the ICU. If we want the sodium higher to bring down cerebral edema, we give salt(IV)to drive it up(some time up to 160-170 in extreme cases). If the sodium is too high and there is no longer cerebral edema, we bring the sodium down gently, with oral water, or with IV water(with dextrose, or lower than normal saline--half normal or quarter normal)
Originally Posted by brian chontosh
Every time I try to wrap my head around the science it starts to hurt. My background doesn't fairly allow to dig into a cursory understanding of the biochemistry of AVP/ADH and such. I'll leave this for someone with the credentials to tackle it.
However, the reductionist in me wants to refocus the point: Overhydration is the issue. Let's not conflate tonicity, heat illness, or CHO consumption to increase performance.
Overhydration is killing.
Before the ACSM/GSSI changed the rules on hydration this disease (EAH & EAHE) didn't appear to exist. The first reported case was 1981. This disease was created when endurance athletes started consuming excessive fluids. It doesn't matter if the fluid is water or sports drink really. How and Why were recommendations changed so suddenly when there wasn't a problem? And, why have the recommendations only gradually and softly started to return to original dictates of thirst? I would have expected the opposite - a gradual changing of the rules at the onset and when deaths occurred an immediate, loud, and exhaustive correction.