The monster-inspired movement in this exercise is incredibly effective at shrinking your waist by targeting a number of different muscles. And if typical ab work, like crunches, irritates your neck, give this move a try—there’s no crunching or pulling involved. Watch as fitness expert Chris Freytag demonstrates how to properly perform this move, then give it a try! ​ ​ More: 50 Simple Ways To Get A Flat Belly