The guy who sold me it told me to store the tub upside down as the active ingredient would settle at the bottom. Didn't do this and me and my mates first go proved pretty unspectacular, however.....next time I turned it upside down and we took a more generous helping... ha, that did it!! we went to the gym and had best session ever, think I beat my best deadlift by about 30 pounds and had to be dragged out of there... didn't sleep a wink either!! also took it once back when I did JKD and we were going on a seminar with Mauricio Gomez of Gracie Barra fame, well night before was my birthday so we were out on the lash and came home to watch De la Hoya v Trinidad ( ? ) so consequently had around 2 hours sleep... didn't want to look tired and waste day so I naturally suggested a little pick me up to get us through the day. Not good after no sleep, hardly any breakfast or fluids and especially training in a small room on a boiling summers day!!! ha, I honestly thought at one point I was going to die... no joking either, I was red as a phone box and felt my brain was going to boil. Had to rush off to toilet and stood there in front of these shocked leisure centre users with my gi ripped open throwing half a tonne of water all over my body and head before collapsing in the corner!!! ha. that said I felt fine in around 10 minutes and went back and finished the class. Never used it again though!! Always prided myself on been drug free but do wonder about that tub!!