Coconut water is a natural and refreshing way of rapidly hydrating. High in potassium, low in sodium, no fat, no cholesterol, no added sugars - forget commercial energy drinks, this is far superior and your body will thank you for it. Fresh from the young coconut is best, but if you live where there are no coconuts growing, "not from concentrate" 100% pure coconut water is relatively easy to find. My experience is that is should be opaque in appearance, the clear versions just don't taste right - get organic and fair trade if possible.