* Many athletes become confused by the difference between the external obliques and the internal obliques. In simple terms, the external layer of the obliques serves to pull or hold the torso to the side—as in a side bend or a human flag. The internal layer rotates the body, as in twisting motions. The flag movements are the best exercise for strengthening the external obliques. If you combine this technique with a safe bodyweight twist—like the ones I’ll show you in chapter seventeen—you’ll have the perfect total obliques workout.