But planks can get boring unless you mix things up. It's a position that you hold for a minute, and once you get good, it can get incredibly easy.

Good thing there are so many more options than just a basic plank. Planks may seem simple, but by varying everything from hand position to leg position to the amount of balance points, you can instantly increase the challenge for your core . And if you check out the last move in this video, you'll find an awesome way to do so while simultaneously shaping your triceps .

You can balance on your hands instead of your elbows to challenge yourself even further. Extend them away from your body in different directions so that your torso is lower to your ground.

You just can never do this workout enough. Plank position teaches your abs to brace hard and pull your ribcage down, something people often forget to do while sitting at their desks in the office. Try a few of the ideas from this videolike the wall plank or the shoulder tapnext time you're looking for a new way to work your core to perfection.

(If you're looking for more ways to get that six-pack, try Men's Health Anarchy Abs for calorie-torching workouts that strip away fat from head to toe.)