I've just found these 2 exrcises for the lower abs, so thought they may be of help....
Reverse Crunches:
Lie on your back and lift your legs so they are perpendicular to the floor, with your knees bent a little and legs crossed at the ankles.
Put your arms on your side so they are resting on the floor.
Keep your shoulders relaxed, rest your head on the floor nicely while keeping the back straight at all times. Now lift your hips off the ground and push them towards the ceiling.
Hold, hold, hold now slowly bring yourself to the initial position.
Leg Lifts on a Chair:
Sit on a chair with your back flat against its back.
Now with your hands on the desk, lift your legs off the floor, and hold them for 8 seconds.
Slowly go back to the initial position.
Repetition is key, you can do it every day while you are working. But if you start feeling any pain, stop, as it can be a sign of overtraining.
Reverse Crunches:
Lie on your back and lift your legs so they are perpendicular to the floor, with your knees bent a little and legs crossed at the ankles.
Put your arms on your side so they are resting on the floor.
Keep your shoulders relaxed, rest your head on the floor nicely while keeping the back straight at all times. Now lift your hips off the ground and push them towards the ceiling.
Hold, hold, hold now slowly bring yourself to the initial position.
Leg Lifts on a Chair:
Sit on a chair with your back flat against its back.
Now with your hands on the desk, lift your legs off the floor, and hold them for 8 seconds.
Slowly go back to the initial position.
Repetition is key, you can do it every day while you are working. But if you start feeling any pain, stop, as it can be a sign of overtraining.