text: i want a flat stomach ( tight abs) how do i flatten up my mid section with out losing weight.? i want to keep my nice round butt, but i want to lose my semi gut! leg lifts.  lie down flat on ur back.  put ur hands on under ur butt, then slowly lift ur legs up (keep them straight!!!) it burns i know but its the best way.  just keep liftin ur legs up and down with out ur legs touchin da ground.  its sweet and effective.