If you have been running for a while, you have almost certainly heard that it is essential to remain well hydrated. Dehydration has been blamed for premature fatigue, pulled muscles, cramps, dizziness, nausea and heat exhaustion. But what are the facts?

I have recently been reading The Runner's Body by Tucker and Dugas , and it is interesting to read their view on this subject. They note that runners who finish marathons in the fastest times are those who lose the mo...