Mineral H2O May be a Better Hydration Choice
Mineral water may actually be more hydrating than standard bottled water.
According to a recent study in the Journal of the International Society of Sports Nutrition, mineral waters typically contain calcium and bicarbonate, which is an electrolyte. Both can help to improve hydration levels, which in turn can help to prevent fatigue.
Look on the mineral water label to see if it has about 300 milligrams of calcium, about 800-900 mgs. of bicarbonate and some magnesium.
Remember that once you actually feel thirsty, you are usually already dehydrated. Hydrate before and after exercise. If exercise lasts for more than an hour, then you should be taking some water breaks during the fitness activities as well.