So, ive been trying to lose weight for the past month and a half now, and ive lost about 15 pounds. I eat 3 square, helthy meals a day. Workout every other day, and do cardio for 40 minutes every single day. Im 16, i use to weigh 168, now im 152. When i stand up straigh, i have a flat belly. But, when i sit down, or slouche(rest my elbows on my knees..) you can see belly flab...like.. some rolls. I dont get it!? Do i need to turn my belly blab in to muscle, by doing crunches/situps every night or something? Please, any tips/suggestions are really appreciated!