Search around here and you'll find out about most anything supplement and exercise related. You will also learn, for better or worse, that most people (here) agree that GNC is about the last place on the planet to purchase sports nutrition. Big-named, over-hyped, over-priced, under-dosed nothing special stuff, mostly. That's nothing against you. It's honest work, and if you are interested in bodybuilding/nutrition, it's a reasaonable place to start. Good luck!