This is a very simple concept, that is very similar to calories in and out. Just think water in and out. The best way to measure water loss is through weight changes. 16oz of water is equal to 1 pound, and weight changes that happen over a 12 hour period is completely due to water loss or gain. Always put back in what you take out.. plain and simple.

The main concern with hydration for active people is electrolytes. Sports drinks have attempted very hard to make this a very important discussion. For any of us that train for at least an hour with moderate to heavy sweat loss (1-2 lbs/hour) we need some salts baby! This ensures proper cellular and nervous system function. There are many ways to get salts, but adding a little extra salt to food, or taking an electrolyte supplement is very normal, and very common.

Good luck, and keep sweating!