Exercises from the community
Bicycles (abs)
Bicycles on a hanging bar work endurance and hypertrophy for the abs through a longer range of motion than the floor version, recruiting the obliques as a synergist throughout. Hang from a pull-up bar with your arms fully extended and core braced. Drive one knee up and across toward the opposite side while extending the other leg, then alternate in a smooth pedaling motion, keeping your torso as still as possible.
Reverse Crunches (abs)
Reverse Crunches specifically target the lower abdominals by moving the hips and pelvis instead of the shoulders, filling a gap that standard crunches don't reach as directly. Lie on your back with knees bent and feet off the floor. Curl your hips up and in toward your ribcage using your lower abs, then lower back down with control, stopping before your feet touch the floor to keep tension on the muscle.
Modified Knee Raises (abs)
Modified Knee Raises isolate the lower abs with an easier range of motion than a full hanging or straight-leg raise, making them a good stepping stone toward tougher lower-ab work. Sit on the edge of a bench or lie on your back with knees bent. Curl your knees up toward your chest by contracting your lower abs rather than swinging with momentum, then lower back down with control until your feet are just short of the floor before repeating.