Pre-exercise Hyperhydration: Comments on the 2007 Acsm Position Stand on Exercise and Fluid Replacement

Goulet EDB. Pre-Exercise Hyperhydration: Comments on the 2007 ACSM Position Stand on Exercise and Fluid Replacement. JEPonline 2008;11(2):64-74. In the latest hydration guidelines of the ACSM (February 2007), two paragraphs are dedicated to the effects of preexercise hyperhydration (PEH) on exercise endurance performance (EEP) and physiological functions. With respect to its ergogenic potential, the Position Stand of the ACSM concluded that PEH only occasionally improves EEP, or offers no clear performance advantage. These conclusions are, in my opinion, not a perfect reflection of what is really known about the ergogenic value of PEH, as they were derived from results of studies whose experimental designs are inadequate to determine the ergogenic property of PEH. In this opinion/review article, I will provide an alternative view of the effect of PEH on EEP using newly published, as well as results not discussed by the ACSM Position Stand. When the literature is carefully reviewed, one finds out that only few investigations provide clues about the effect of PEH on EEP, and collectively their results suggest a performance-enhancing effect in athletes. On the other hand, the Position Stand judged that this strategy provides no thermoregulatory or other clear physiological advantages, and that it increases the risk of hyponatremia and of having to void during competition. I am not in total agreement with these conclusions and here I will present evidence suggesting otherwise. I believe that it is important to provide an alternative view of the effects of PEH on EEP and physiological functions than that given by the ACSM’s Position Stand due to the influential role of this organization within the exercise science community.