SUL water

Sounds to me like an ideal situation for an Aarn pack. And ditto the VBL suit. Even if you don't funnel the perspired moisture into a container to re-use, the increased humidity at your skin will slow total perspiration. Sure, you'll be miserably, but that's the sacrifice of SUL.

RE: Tanking up before you go-this can have a detrimental effect if you are out for more than a day or two. Super-saturating your kidneys with masses of water turns your kidneys into water excreting monsters. This is in fact the exact trick that most bodybuilders use to get majorly dehydrated…drink as much as you can for a few days and then cut right back 2 days out from a show. Single best way to get very dehydrated!

A better bet si to try the opposite. Cut back on your water for ~ 2 days before a trip. That will make your kidneys more economical. Also cut back on your salts before a trip, and then add them back into your drinking water on your trip. Dilute hydration salts such as Gastrolyte are ideal, and don't weigh much.

Intersting comments Alison. I just follow my instinct with water intake. Little and often seems to work best for me. I've never carried special salts, but carry nuts, seeds and dried fruit as a frequent trail snack. Which natural foods do you recommend?

Yeah Roger, a little and often is best. Anyone ever try that Kalahari trick of holding the water in your mouth instead of swallowing it? I find it takes a lot of discipline, but works well.

Dried fruits (such bananas and apricots) are great for potassium, salted nuts for sodium. If you can get nuts that have been salted with pure sea-salt it's even better as it covers a whole range of beneficial minerals.

Oh yeah, I forgot about glycerol/glycerine!

http://www.sportsci.org/traintech/glycerol/rar.htm