You don't have to wear a flannel coat in order to develop a lumberjack's strength and definition in your midsection (besides, people will probably just think you're pushing for a rebirth of grunge). And, you never have to actually swing an ax. But, you still do need to put in time doing some good, old fashioned wood choppin'.

The Woodchopper is a great way to target your obliques, as well as many other core muscles. To do it, start by holding a single dumbbell at waist level with both hands. Keep your feet just slightly wider than shoulder width apart, your knees and waist slightly bent. Twist your torso upwards and away from your legs as you pull the dumbbell over the shoulder you're twisting toward. At this point, the dumbbell should be over your shoulder, with both hands still holding onto it. Finish the move by lowering your torso and driving the dumbbell downward and diagonally across your body, toward the foot on your opposite leg. This constitutes one full rep. Stopping there, obviously, isn't even close to being done. Shoot for at least eight to ten on each side.

Words, words, words ... there's only so much you can do with them. By now, I may have thoroughly confused you with those I chose to use in describing the Woodchopper exercise. Thankfully, there is a little something called the internet, and on it exists a plethora of photographs and videos. Here's one I found that describes the mechanics of this exercise far better with images than I did with text. (Note: in this video, the demonstrator uses a cable instead of a dumbbell).