If you want to look fit, a flat stomach can really make all the difference in the world. Unfortunately, sit-ups suck, and so do most of the other exercises designed to get your abs into shape. Nevertheless, you need to get this area toned if you want to look good in that bikini, right? So what do you do? You do what the rest of us normal people do -- crunches on a stability ball.

What makes them so much better? They're easier, for a start. And you'll feel it in the right places pretty darned quickly. Lying on your back on the floor can do a number on you back after 50 sit-ups, and you *still* might not be targeting your abs as well as you could be. Try 50 crunches on the stability ball and see how fast you feel it -- and how fast you start to see results.

Step One

Get you a stability ball.

Step Two

Lay down with your back centered on the ball. Your butt should be right at the end of the ball, and your feet should be planted firmly on the floor.

Step Three

Place your hands behind your head and raise yourself up into the crunch -- you don't need to do them fast, and you don't need to sit all the way up. In fact, you'll probably find it more effective if you don't.

Tip: If you have a hard time doing it with your hands behind your head, don't. Start with your hands at your sides and then work up to it.

If you're looking to increase the intensity of your ab workout, this is the easiest way to do it.

Step One

Lay down on the stability ball the same way you did with the first exercise.

Step Two

Place your wrists (with wrist-weights on) behind your head as you normally would, and proceed with your crunches.

Tip: If you have trouble keeping your balance, do these in front of a wall and brace the tips of your shoes against it. Not too much... you don't want the wall holding you up; it's only meant to help you keep your balance.

If you really prefer the floor to being on a stability ball, you can give these hand-to-feet stability ball passes a try. Simply lay down on your back and pass the ball back and forth between your hands and your feet. It's not as easy as it looks, and your abs will surely feel it when you're done.

See the video below for a complete demonstration.