In 2008, she finished seventeenth in the 10,000 metres at the Olympic Games. Shibui won both the Osaka Ladies Marathon and the San Francisco Marathon in 2009. At the 2011 Tokyo Marathon she was in a leading position with only two kilometres to go but slowed to relinquish her lead, ending up in fourth place. She tried to gain a place on the 2012 Olympic marathon team, but her fourth-place finish at the 2012 Nagoya Women's Marathon was not enough for selection.