5 - 10 pounds in a week isn't really that hard to do. I have had to cut alot more in that amout of time before I had never missed weight. Run, whatch your food intake, stick to low fat high protien, and drink water. It is really important that you do not dehydrate yourself when your cutting weight, if you do you will make weight but feel like crap on the mat. Have you thought of going up a class in weight? You might find you feel better at a slightly higher weight.