"If you're at the point of feeling thirsty, you're already dehydrated."
Myth No. 3: By the time you feel thirsty, you're already becoming dehydrated
Maybe if you're an elite athlete running a marathon or a hotshot tennis player sweating in the noonday sun -- but not if you're going about your everyday activities.
Thirst is, in fact, a very sensitive mechanism for regulating fluid intake, according to Barbara Rolls, PhD, a nutrition researcher at Pennsylvania State University. In a 1984 study in Physiology and Behavior, she and a group of colleagues at Oxford University followed a group of men as they went through their normal day. Left to their own devices, the volunteers became thirsty and drank long before their hydration levels showed any signs of dipping.
Says Rolls, "If people have access to water or other fluid beverages, they seem to do a very good job of maintaining hydration levels."
When I exercise I am thirsty within 10 minutes but I still have 30-50 minutes of hard aerobic activity to go. If I was "dehydrated" I would be weak, dizzy and my strength and endurance would drop significantly. Instead I am strong throughout and finish with a sprint, how do you explain that? My urine isn't darker either.
I average 4-5 glasses per day of water, the rest of the water comes from food.
In the past decade a number of inexperienced runners have died due to over consumption of fluids. This has lead officials to change their language to "Rely more on your thirst level rather than forcing yourself to drink.".
The next thing companies pushing product will have us believe is that you must eat before you get hungry because hunger is a sign of starvation, lol. In the sixties you didn't see people toting water bottles and there was no mass incidence of dehydration with semi-delerious people wandering around.