Just because our stomachs might be the number one body part that drives us crazy when trying to lose weight, doesn't mean we're crazy about doing crunches or other tummy-flattening exercises at the gym (even Jillian Michaels admits it). Enter "Biggest Loser" trainers Bob Harper and Michaels with their top gut-busting tips, which call for small changes like adding mustard to your favorite sandwiches and fueling up with more bean-based dishes. Read the rest of their slim-stomach tips here.