External Oblique - these muscles are on the side and front of the abdomen and wrap around your waist.
Internal Oblique - these muscles lie under the external oblique and run in the opposite direction.
--Lie sideways on your left side.
--Raise your body, resting on your forearm and side of foot. Keep your right leg on top of the left leg. Keep your body stiff and brace your torso (as if taking a punch). Keep your head in line with your torso (don't let your head drop or jut out).
--Hold for the required count. Relax and repeat again. Do all repetitions on one side and then switch to the other side.
You can do exercises like planks, side planks, bridges and cobras up to 4 times a week. They will sculpt your abs and protect your low back from injury!