Take a look at the various exercises that work various areas of the abdominal wall. Some exercises will work all areas. You should incorporate one of the exercises below to incorporate at the end of each of your abdominal workouts.  Levels of Difficulty

Abdominal Vacuum Angled Broom Twists

Double Crunch

     
Oblique Press Cross Split Leg Crunch

Straight Leg Crunch

     

Weighted Twist Standing Leg Lift  Standing Broom Twist

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