"After pregnancy, I had about one inch separation of my abdominal muscles, so I completely understand your situation. I strongly suggest to do strengthening exercises that cause you to "clench" your abdominal muscles. For example, doing a plank exercise requires you to hold your abdominal muscles tight - you don't need to move them in any direction to be able to gain strength and toning. Just tightening up your abdominal muscles when you are laying down, standing up, sitting, etc. is another great way to help with separated stomach muscles (i.e., "clenching" like doing kegel exercises). Research shows to stay away from crunches."