You have a front side and a back side, right? So when you work your abs, be sure to strengthen your lower back, too, for a balanced core. Back extensions are the perfect move; here’s how to beef ’em up.
Tip 1: Grab a dumbbell plate or a medicine ball and hold it while you perform your back extensions. Make sure it’s not so heavy that it compromises your form–you should be able to keep your back flat and head and neck in a straight line, lifting from your lower back and glutes with tight abs.
Tip 2: Change up your range of motion. Do one set beginning from fully bent to just halfway up. Then do another set beginning from halfway up to the top of the movement.