I am 48 kg 165CM, less of weight. From the beginner I'm decided going to GNC for more information, they recommend gain weight powder for me. Although I want build muscle, but come from the first point I have to gain weight after that muscle right? In the same time can I mix them protein powder and gain weight powder ? I really don't want have those big big muscle as you know I wanna be stronger, because for my age now I am really thin.

Nonono..I just wanna looking fit. I believe healthy food should have a good result become fit.