Jack Hartford on Instagram: "Hanging leg raises are hands down my favorite ab movement. Every variation I do has taught me serious ab control, built strength, and helped me develop my lower abs better than anything else. Regular hanging leg raises hit the lower abs hard and force your core to stabilize your whole body, no room for momentum. Hanging oblique leg raises bring in that twist that lights up your obliques and helps shape your waistline. And when I throw a box between my legs and jump s