Loaded Russian twists, 10 per side. Resist with a weight. Turn right until your arms are parallel to the floor. Return to the start and switch sides. Kettlebell windmills
Turn your hip. Slowly bend until your free hand touches the floor. Keep the kettlebell over your head. Repeat in reverse.
Another ab workout is the hanging leg lift. Raise your legs and body 90 degrees while hanging from a chin-up bar.
The monkey chin/crunch is a stand-alone workout since it's comparable to the dangling leg lift yet distinct. Hang from an underhand chin-up bar.
Core-building barbell ab rollouts follow. Place a barbell, weighted with 5-or-10-pound plates, on the floor in front of you so that you are on your hands and knees (like in a kneeling push-up posture).
Flex your hips to hyperextend your lower back. With the hips motionless, flex the waist and engage the abs to move the elbows toward the center of the thighs.
The side plank is similar to the regular plank, except you lean on one elbow and swap sides to work both obliques. Once you're comfortable, try weighted side planks with a dumbbell.