Researchers recommend runners only drink when thirsty.
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.