5'8" 135. Lift like 3-5 times a week, train abs at the end of every workout. (1.5 min plank, 1 minute plank each side, 1.5 min hollow hold then 15-20 leg lifts with 15 lb weight. Repeat.) Still can't get the bottom 2 abs to show. Any advice? Are some people just genetically incapable of it?