While you can work your abs lying down, the most effective core exercises are functional moves done standing. Functional exercises mimic everyday moves and easily translate to real-life activities. Equinox trainer Lauren Fairbanks recommends the wood chop using the cable pulley machine to strengthen the abs and back while sculpting a toned torso. "It's a full-body move that works the glutes and the shoulders, and just about everything in between." The primary focus of the exercise is the abs, especially the obliques, which drive the twisting motion.