By Rachael Moeller Gorman, "Liquid Assets," July/August 2011

When you’re well hydrated, the water inside and outside the cells of contracting muscles provides adequate nutrients and removes waste efficiently so you perform better. Water is also important for lubricating joints. Contrary to popular belief, muscle cramps do not appear to be related to dehydration, but, instead, to muscle fatigue, according to Sam Cheuvront, Ph.D., an exercise physiologist for the U.S. Army Research Institute of Environmental Medicine.
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