I went on a serious hike today with some very fit people. They mentioned the use of pickle juice and mustard as a very quick way to help restore one's electrolytes (in addition to water) on the trail. (Yes, I know -- the best bet is to never get dehydrated or allow one's electrolyte levels to go astray to begin with.)

They said they keep mustard packets in their packs and come to think of it, I have seen empty packets on the trail. Has anyone else heard of using pickle juice and mustard in this fashion?