When i used to take my DR. friends out fishing on the ocean,no shade,HOT,they used to bring salted pnuts to snack on and plain water in the cooler....also said NEVER drink more than your body wants to,it will tell you when it wants water.you get thirsty...do NOT over hydrate..
no. what you need to do is drink enough water to maintain regular near clear to slightly yellow color urinations. if you wait to begin drinking until you are thirsty than you are already entering the early stages of dehydration.
thanks to modern marketing, the need for electrolyte replacement is VASTLY overrated, and most drinks are mixed way to heavily and contain way to much suger.
the nuts are actually a decent idea though, especially as it means your regularly consuming small amounts of food over a long time period. the same goes for water, in mountain/bigwall/rock climbing and for long mountain bike rides i generally use a camelback (filled with plain water), which makes it very easy to just take a sip at frequent intervals.
as mentioned early in the thread, the emergen-c stuff is miracle stuff. frequently on long multi-day climbs where its very hard to maintain good nutrition i'll start the day off with one, and will frequently have another towards the end of the day or whenever i'm feeling kind of bonked.
but hydration is absolutely key, strength, stamina and your mental acuity will drop off very significantly even if you become even moderately dehydrated. i can't emphasize enough, pay attention to your urination. keep it clear and frequent. your in the woods, its not like its an inconvenience.
i also try to "camel up" at the start of the day. don't drink enough to feel bloated, but try to put down the maximum amount of water at the beginning of the day. while driving to the jobsite, be downing the stuff.
i'm not trying to sound like a know-it-all, but as far as this topic goes, its pretty common knowledge amongst people that do what i do.
heres the resume:
halfway up the dunn/westbay route, east face of longs peak (14,252 feet it think), rocky mountain national park, colorado. hiked in and out over 200 pounds of gear, 16 miles round trip, 6 days car to car, 3 days on the wall, and a continuous 36 hour decent, over 1000' of vertical to overhanging climbing at 5.10/C3+, note the water bottle on my harness. no hydration problems despite the altitude and the fact that it was in the 90's for a couple of days and we were pulling 14 hour shifts climbing and hauling.