When I lived in Colorado, I learned the importance of staying hydrated due to the dry, mile-high elevation as I worked out, and now that I live in the desert dryness and heat in Las Vegas, I carried that need to stay hydrated when I work out with me. But if you are watching your calories, you can’t just choose any hydration drink. Pick the wrong one and you can end up downing the equivalent calories to a bottle of regular soda in the neighborhood of 200-300 calories!