So Long, Muffin Top: A fat-burning, belly-toning routine that’s guaranteed to whittle down your middle.

Are you noticing more ab flab with each passing year? An estimated 50 percent to 60 percent of the amount of fat in your midsection is said to be dictated by the genes you inherit. But how you live and changes that your body goes through as you age also play a major role in increasing in waist size. Too much stress, too little sleep and eating too many calories can contribute to belly bulge as well. Click here to find out more: MSN Health & Fitness site .