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Race Hydration and Hyponatremia
Related: electrolytes, Everest Challenge, hard core, health, hyponatremia, nutrition, Rides
Consumed excessively, water is deadly.
The Everest Challenge demands precision attention to hydration and food, with the most serious (and possibly life threatening) challenge being hyponatremia.
Hyponatremia(also known as water intoxication) is a loss of too many electrolytes— everything starts shutting down. Every year in the Everest Challenge, riders end up with an IV in their arm, so pay attention here.
If you test your luck with even more water, you will impair your mental function, the most likely result of which is a crash leading to severe injury on a descent. Alternatively, seizures or brain damage are other fun side effects.
Carrying enough water
See Water Bottles For Cycling.

My experience
My 2004 Everest Challenge was a hot one. I consumed about 2 gallons of fluid that day (mostly diluted Accelerade), and I was careful to scarf an appropriate number of Endurolyte capsules at every water stop. As well as Gu energy gel @AMAZON (skip the flavors, get plain).
At the end of the first day, I had consumed 2 gallons of fluid. There were 1/2" high salt crystals growing out of my helmet straps (wish I had taken a photo!), and the local wildlife was running after me to lick legs.
Recovery the first day is crucial— fluids and appropriate food, and plenty of rest.

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