At the recommendation of an AA enduro & hare scramble guy, I recently used Accelerade during my last two enduro's. This stuff is awesome! I used to use Revenge but after 2 or so hours, I'd get start to get nauseaous and after 4 hours I didn't even want to drink it anymore. This led to dyhydration and fatigue. Accelerade eliminated all of these problems. I used the fruit punch flavor which tastes great (when you are thirsty, ok when your not) and it makes you want to drink more. I drank 120 oz in each of my last two enduros, and felt 100% better. The same company makes a product called EnduroX4 which helps you recover faster. I haven't tried it yet, but if it is half as good as the Accelerade it will be more than worth it. Give it a try.