Okay so im 5\'4 143lbs and 17 years old. I couldnt be anymore excited to have bought z-3 yesterday. I started taking it before me and my friends went out for dinner and today before breakfest i havent had any side effects (yet :D ) which is awsome. As far as some people on here go saying dont wast your money its honestly really lame cause it works diffrent for everyone just because it didnt work for you doent mean it wont work for someone else. And yeah working out does make a diffrenc but not all the diffrence in my opinion either way i encourage it just start out slow and i think you will see a big result after a while