I am 26 yrs old and in high school I developed a 6 pack. I have always been very slim and last year I tried to gain some weight and put on some but developed a little pouch. After that, I lost weight again due to working a physical job and my stomach was flat again. Since that point I have been trying to gain. Since April, I really have been eating a lot and trying to pick up some weight. I've also been doing some push ups to build my chest. After I do the pushups, I drink ensure plus for protein. One area that's bothering me is my belly. I'm still slim and my belly seems to go outward from my breastbone instead of being flat. I still have a slight pouch on my lower torso. If I stand up straight with good posture and relaxed, my belly curves outward. Yesterday I did some crunches and situps and this morning I really noticed how much my belly went outward. Did I build up some muscles in my abdomen that are pushing it outward? What can I do to get a flat torso?