While this certainly works, the first and second time I took it it made me feel rather sick to be honest and actually hampered my workout sessions, and ive never gone to the toilet so many times (apart from food poisoning) in the gym ever, I’ll agree with the review brothers on YouTube at a full scoop it is too strong , not the amount of caffeine (I can take allot) but the other stimulants in it must be not agreeing with me (could be the food coloring though or the lovely taste mix they use!), however after basically calling it a laxative!, I can tolerate 3/4 of a scoop without running to the loo!, and mixing it with my pump based pre I get a really good workout, be warned it is strong and not for everyone, hope this helps everyone