After trying almost everything on the market I found a new product specifically designed for the heat which means it has a very high electrolyte content. It is designed by the former Medical Director of the Eastern Canadian Ironman and the Subaru Series Ironman events. It has a blend of 5 electrolytes to replenish you with the same rates and ratios that you are losing them at. At the same time it has no artificial ingredients and uses dextrose as the primary carb (this is what they use in oral hydration solutions in hospitals). Dextrose is the most efficient carb to prevent bonking, is the most efficient for facilitate electrolyte absorption, and is the easiest and quickest on your system to be processed. This product also is 35x lower in acid than Gatorade and has a natural lactic buffer (to reduce muscle burn). To top it off, the maker guarantees it (you will not cramp, bonk or get an upset stomach, or your money back)!
www.eload.net I have now been using it for 3 years with phenominal results.