Her personal best for that event is 9:55.93 minutes.
She took up the steeplechase event in 2007 and represented her country at the 2007 World Championships in Athletics, held in Osaka.
Her first major medal came at the 2009 Asian Athletics Championships, where she won in a championship record.
Earlier in her career, Arai was a frequent runner-up to Minori Hayakari at the Japan Championships in Athletics, but she took national titles in both 2012 and 2013.
She also placed fourth at the 2013 Asian Athletics Championships.