Staying hydrated is important for optimum health, and proper hydration is certainly important when running long distances. But new research has found that you can get too much of a good thing when it comes to hydration. In fact, researchers have found that nearly half of runners may be drinking too much water or sports drinks during races. Drinking too much fluid while running can dilute the sodium content of blood to abnormally low levels and cause a potentially fatal condition called exercise-associated hyponatremia.
According to the survey of runners by Loyola University Health System researchers that was published in the June 2011 issue of the British Journal of Sports Medicine, 36.5 percent of runners drink according to a preset schedule or to maintain a certain body weight and 8.9 percent drink as much as possible. This drinking-behavior is in contrast to what the International Marathon Medical Directors Association recommends when it comes to drinking and running: drink only when you're thirsty.
"We have been trained to believe that dehydration is a complication of endurance exercise," Loyola exercise physiologist Lara Dugas, PhD, a co-author of the study, told ScienceDaily
. "But in fact, the normal physiological response to exercise is to lose a small amount of fluid. Runners should expect to lose several pounds during runs, and not be alarmed."
Want to learn more about the signs and symptoms of hyponatremia? Check out this article on overhydration