Abdomen not flat
You will need to determine what is causing the bulging in your mid-section, as ab exercises may not resolve your concern. If you didn’t achieve satisfying results, you may want to consider returning to your surgeon to discuss your concerns.
Most docs don't address the upper abdomen nor the sides when they do a tummy tuck. That is why you probably need lipo to get the best results. Further exercise will usually only improve the results after lipo.