Well, you cannot go wrong with water during a workout, but if you are going to exercising longer than one hour then you can try some different options. If you are going to be doing an endurance type of event or activity, like running, then you will want to have an electrolyte drink to replenish your carbohydrates. There are various brands out there, but I would stick to the well-known brands, but there are also some great powders out there that you can make at home with water. If you are interested in the powders, I would visit your local health food supplement store and see what your options are.
Oregon Personal Trainer