The Fitness Zone
Almost half of participants in running events may be consuming too much liquid according to US researchers.
A team from Loyola University in Chicago found that rather than simply drinking when thirsty, 36.5% of surveyed runners drank according to a schedule or to maintain body weight and 8.9% drank as much as they could.
Almost a third of the 197 study participants believed (wrongly) that they needed to consume additional salt when running and nearly 60% said they drank sports drinks with electrolytes to avid low blood sodium. Ironically, the researchers noted, consuming too much water or sports drink is the main cause of low sodium in runners and can cause potentially fatal exercise-associated hyponatremia, prompting researchers to conclude, Many athletes hold unscientific views regarding the benefits of different hydration practices'.
Study author and Loyola sports medicine physician Dr James Winger said that the safest known way to hydrate during endurance exercise is to drink only when thirsty.
Study co-author and exercise physiologist Lara Dugas, PhD, said, We have been trained to believe that dehydration is a complication of endurance exercise. 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.
Source: British Journal of Sports Medicine