Never request to do SIT UPS ever again.

"Athletically, the abdominals primary role is midline stabilization, not trunk flexion. They are critical to swimming, running, cycling, and jumping, but never is their stabilizing role more critical than when attempting to drive loads overhead, and, of course, the heavier the load the more critical the abs role becomes. We train our athletes to think of every exercise as an ab exercise but in the overhead lifts it’s absolutely essential to do so. It is easy to see when an athlete is not sufficiently engaging the abs in an overhead press – the body arches so as to push the hips, pelvis, and stomach ahead of the bar. Constant vigilance is required of every lifter to prevent and correct this postural deformation." Coach Greg Glassman
PLEASE DONT ASK ME TO HELP YOU LOSE WEIGHT AROUND YOUR STOMACH BY WORKING YOUR STOMACH!!
Spot reduction refers to the desire to pick a spot on the body and exercise that spot in order to reduce fat from that spot. Spot Reduction is the WORST myth.
Much of the energy and calories to fuel exercise are brought to the muscles through our blood. The great travesty of exercise is that our body does not take calories directly from the spot you are exercising.
What does this mean? This means that a lower abdominal exercise by itself is not enough to disintegrate all the fat around your stomach.
Doing stomach exercises is a very positive thing (burns calories, builds strength and coordination, improves posture, increases endurance, and can aid flexibility) in the quest for weight loss and a toned waist, but it is only a piece of the puzzle.
In order to get the best abs, you must do two things… Develop your core and stomach muscles & Lose weight &/ or decrease your body fat percentage