The elite athlete’s challenge to maintain proper hydration

A considerable amount of attention has been paid to the consequences of dehydration on sports performance. During ultra-endurance events such as marathons and triathlons, many of the competitors will finish with dehydration of 4% body mass or more, and such levels of hypohydration have been shown to significantly impair exercise performance. Even in shorter events or stop-and-go sports, dehydration has been shown to have a negative effect on performance. Should the elite athlete attempt to maintain euhydration? What strategies should he/she follow?
There are two challenges in this context. One is to maintain proper hydration over time, which means drinking enough of the appropriate fluids to recover after practice and/or competitions, and keeping a regular fluid intake during travel and daily living to compensate for all fluid losses. Starting competition already in a state of dehydration has a deleterious effect on performance, as has been shown by Armstrong et al. in 1985, in track running tests of 1,500, 5,000 and 10,000 meters. For this reason, athletes are advised to regularly assess their hydration status by monitoring their first urine every morning. This urine should be abundant and clear, with a specific gravity of 1.010 or less. In addition, unnecessary fluid losses should be kept at a minimum by staying out of the sun and heat and avoiding non-sports related exertion in the heat.
The other challenge is to avoid dehydration during competition or training sessions. This is particularly important when physical exertion lasts more than an hour or so, and the only way to do it is to drink enough of the right fluids during the event or practice. Many athletes consider that the time invested in drinking is not worth the benefits of maintaining hydration, and do a very poor job at maintaining euhydration. The relevance of this will vary depending on the sport: 10,000-meter runners should not drink during the competition, but they will certainly benefit from drinking during training. Marathon runners or triathletes, or football and basketball players on the other hand, compete long enough and have enough opportunities to drink and should attempt to maintain a better level of hydration. Knowing one’s own typical sweat rate and drinking during regular practices can be used to develop an individualized hydration schedule to be used in competition, targeting the best balance between euhydration, comfort, and maximum performance.

Suggested reading

[1]. Aragón-Vargas L. (2004) in Ciência do Futebol. Barueri-São Paulo, Manole.
[2]. Kavouras S.A. (2002). Current Opinion in Clinical Nutrition and Metabolic Care, 5, 519-524.
[3]. Maughan RJ & Murray R (2001). Sports Drinks: Basic Science and Practical Aspects. London, CRC Press.
[4] Montain S.J. & Coyle E.F (1992). J Appl Physiol,73, 1340-1350.
[5]. Shirreffs S.M. et al. (2003). Med Sci Sports Exerc,35(5), s27.