This product is pretty good for a pre-workout supplement, gives you the extra boost you need without any jitters or any tremblings of whatsoever. very minimal side effects, this contains one stimulant that i know of and that is caffeine, 300 mg of caffeine of a full scoop. but i only take half so thats about 150mg of caffeine, not pretty bad because thats pretty much what you get if you drink a cup of expresso from starbucks. not like other products that contains too much caffeine and later on it causes you sleeplesness and nervousness etc. im currently taking the blue arctic raspberry, not bad, its an ok flavor but not the best. it does give you the focus you need to hit the weights. good amounts of bcaa for the big guns. so far this is one of the best out in the market right now in my own opinion, plus this company is always up to date. banned free substance as well. only thing is you have to at least drink a minimum of 1 gallon of water a day when your taking this, ofcourse even though it doesn't contain any banned substances, we still have to optimize our kidneys and liver. I mean every supplement has to be flushed with lots of water, to clean our system from daily use of supplements regardless if its multivitamins or bodybuilding supplements or etc, it still goes through our kidneys and liver. so for a pre workout this is pretty good, its worth a try just dont take a full scoop on your first few days, just do half and build your tolerance from there, dont go over 1 full scoop in a day as well, that can really cause you some dangerous side effects.. i mean lots of people who think there supplement is not working think they need to keep on increasing the amount, well thats how they end up damaging themselves.. again this product is worth a try.