Doreen;'s right, Marlaine. Water, especially when working out in water is essentail. The pressure of the water on your body actually increases the dehydration. This was brought home to me after my first aqua fit class. Drinking while you're working out and immediately after is required. Sips not gulps to avoid cramping. Also, you might not be eating enough and this could be part of the problem. It's also a good idea to get some protein in w/in 45 minutes of a workout (a protein shake or a HB egg are good suggestions)

HTH,
Nat