It’s important to keep hydrated when you work out. That’s why the need to drink plenty of water or other fluids is always emphasized when people talk about exercising.
But do you ever worry about overdoing it? Possibly you should.
It doesn’t happen often, but there is a condition called exercise-induced hyponatremia (EAH). It’s most common in endurance activities of 4 or more hours. It is the result of drinking too much water and it can be fatal. And don’t assume that sports drinks will take care of it. From the article:
Verbalis also says that sports drinks, which contain some sodium and potassium and carbohydrates, are basically water with a few additives. “There’s a misconception among the sports community that consuming sports drinks rather than water will protect you from becoming hyponatremic. That’s simply not true,” he says. “Drinking too much of anything puts some people at risk for potentially dangerous levels of hyponatremia.”
This can result in there being too much fluid for the kidney to process, and so the fluid goes into the blood, diluting the level of sodium.
So what should you be doing?
Drink when you’re thirsty. Don’t keep drinking just because you think you need to keep to a certain level of fluid intake.