3 Aug But an olive oil or mineral oil enema does not stimulate the colon to . hard masses of stool for so long that enemas and laxatives won't cut it. Pediatr Radiol. ;12(3) Contrast enema demonstration of a colon cut- off sign in a baby with perforated appendicitis. Johnson JF, Pickett WJ. Just wondering if anyone's heard of fighters using enemas to cut weight? It's something people will joke about around the gym but if it can get.