How much running should i run a day to get a flat stomach?

Proper diet: Running alone will not get you a flat stomach. Having "6 pack abs" is a function of what you eat in conjunction with a well balanced exercise program that includes moderate cardio, strength training, and flexibility work..

Not that simple.: For a flat abdomen you must eat healthfully ; be physically active. Calories burned must > calories consumed. To tighten ab's do 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.