got this from the LIVESTRONG site….and I love it !!
What is THE best abs exercise?
“While there’s no single-best abs exercise, crunches don’t work as well as most people think,” says John Romaniello, a strength coach and the owner of romanfitnesssystems.com. In fact, neither do leg lifts or Swiss ball situps. The reason: They don’t challenge your ability to stabilize your body weight against gravity. Exercises that force you to brace your spine and pelvis activate more muscle fibers than any type of crunching movement, which helps build the definition you desire, adds Romaniello. The most common stabilization exercise is the plank, where you position yourself in a pushup position, but place your weight on your forearms instead of your hands. Holding this position for 1 minute will work your abs more than you think (almost 66 percent more than crunches, according to research). But if you really want to carve your core, try reducing your stability by raising one arm, one leg—or both—and holding the plank position for 30 to 60 seconds. Just make sure you don’t allow your core to move or rotate (that’s cheating). While this will challenge your muscles, remember the old adage that abs are made in the kitchen. So it doesn’t matter how hard you train them if you don’t watch your diet.
To your health !