It's great that you're in good shape, and I definitely empathize with your desire to get rid of the dreaded belly fat. The good news is that there ARE ways of eliminating the belly roll.
First off, you should consider hiring a personal trainer. He/she will be able to show you exercises geared towards tightening your "core" (stomach, back, etc.). When these muscle groups are focused on, the fat at these areas will be reduced - and no more belly roll.
Another good idea is to take up Pilates. The exercises done in this activity are geared towards lengthening and toning muscle groups, particularly those in the belly, back and waist. It also helps improve posture and flexibility. See if your local gym has a Pilates class - otherwise look into DVD's you can exercise to at home. Just make sure they cover the basics well so you know how to properly do each position.
You should consider seeing a nutritionist. Although you claim to eat well (and I don't doubt you - Weight Watchers is an excellent program and designed to help people learn how to eat property), you might find that a few additional changes in your diet might help to reduce your overall fat content - which, when lowered, should help to reduce any unsightly belly rolls.
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