when i first started training in karate we could not trink untill after training we did fitness for one hour running, star jumps, sprints, press ups, and abbs, it was hard, i was only 12 when i started and as i grow up and lernt more about how the body works i gave it up at age 24 and whent in to muay thai, a trainer should look after his trainees not his ego. having disapline on the floor is a must in karate but we should allways keep our tranees full of fluids the best we can...interfull drnk brakes are good i know what you mean whitti you try and keep a disapline class if every one thought they could just walk of to get a drink when ever they liked a class could turn into a play group...but to any trainer trying to stop people from drinking through a whole training session should get over there egos and read a book on the body or talk to a trained fitness instructor, get out of that little box you are in,