To fight hidden pockets of fat, be sure to get your heart
rate up when you exercise.
As people age, many tend to develop intra-abdominal fat,
a dangerous kind of fat that slowly encases organs and is
difficult to see externally. However, recent research shows
that exercise that gets the heart rate up, such as brisk
walking on most days of the week, can significantly reduce
a person's intra-abdominal fat.
--Journal of the American Medical Association 2003 Jan 15