Here's some posts by the master FBR
c/p
Metamucil is like the steel wool of soluble fibers. It is not only moving some of the metabolites out of you but a lot of waste products too hence the increase in bowel movements and gas. Not only does psyllium husk help eliminate waste products from you, it helps slough off cells lining the inside of your small and large intestines. This is a good thing as it helps prevent colon cancer as well as one of the best ways to clean out the inside of your body. It seems as though your det was lacking in fiber and your body is going through a spring cleaning. This will stop soon and return to a better than it was state. How much are you taking a day and how much at a time. If you are using the capsules, you should be taking at least 6 at a time. You increased bowel movements is more from the fiber pushing things through your system overall then just the fiber pushing out THC metabolites excreted from the increased exercise.
food high in soluble fiber and some kind of low fat and low to normal calorie diet. A few days before the test get lazy and eat a fattier diet so you aren't burning body fat stores.
Get some soluble fiber like metamucil and see if it helps. If you get the caps take 6 caps 3-4 times a day.