The wood chop is a favorite exercise among trainers. In fact, it's celebrity trainer Gunnar Peterson's favorite core exercise and is fast becoming one of ours, too. The wood chop really works the abs but targets the obliques, helping tone your muffin top. But unlike the static plank, the wood chop targets your middle while your middle is in motion, making this move a serious functional fitness maneuver. Grab a five- to 10-pound medicine ball, and get ready to learn the basics.