How to get a toned stomach without losing weight?

Stomach tone: For flat abdomen eat healthfully ; be physically active. Calories burned must > calories consumed. To tighten ab's: crunches, reverse crunches, exercise ball crunches, pelvic thrusts, lying leg raises, side bridge ; “bicycling” exercise on your back. Engage in regular aerobic exercise (i.e., running, swimming, nordic track, bicycling, kickboxing, walking, cross country skiing, hiking, etc.).