Joslyn Thompson Rule is a Nike Master personal trainer who knows her way around an exercise routine. She claims that doing crunches and sit-ups daily - whether it's 5 or 500 - will do absolutely nothing for your abs. "Just doing sit-ups alone won’t get you rock hard abs because you’re only working to strengthen one singular area, which is like trying to build the outer layers of a house with no foundations underneath." Joslyn explains. She recognizes that sit-ups and crunches are part of core strengthening, but they must be coupled with other exercises and healthy diet habits. Simply doing sit-ups alone won't give you any sort of 6-pack. Eating right is Joslyn's biggest ab secret. Instead of crunching, try munching on almonds. They contain magnesium which helps build strong muscle tissue. Yogurt is another super ab food because it reduces bloating and gas to give your midsection a tight, cinched in look. And omega-3 rich foods like salmon, flaxseed and walnuts help burn fat for a flatter tummy. For workouts, Joslyn recommends incorporating planks, side planks and hollow holds to strengthen deep into your core. She even warns that over doing it on sit-ups can be dangerous and may lead to lower back problems. So make sure you keep a well-balanced workout routine. Try Joslyn's suggestions and tell us what you think! What is your secret to fab abs?