I mentioned in another thread, that years ago my wife (then fiancé) and I took scuba lessons to get certified for diving on our honeymoon. The first part of the lessons were taught in 4-6 hour classes in a large local pool. The instructor was a funny gay guy. When he was giving the introduction to the class we all had our gear on and we were standing in the pool. The instructor told us to drink plenty of water (we had bottles as the side of the pool) as we were doing lots of exercise and we need