Core muscles. They’re the glue thats stabilizes the spine. In simpler words & description they’re like a belt & a girdle put together 2 enable the spine 2 move. The spine is like a fishing rod which enables the other limbs 2 do their functions, if the fishing rod isnt sturdy the limbs’ function wont be optimal or smooth. When we opt for a flatter tummy we should always remember that abdominal muscles alone cant function.