(born 1970) is a Paralympian wheelchair racing athlete from Japan competing mainly in category T54 long-distance events.
Masazumi was the men's wheelchair winner of the 2011 New York Marathon and the 2011 Boston Marathon.[1] He has competed in the marathon in both the 2004 and 2008 Summer Paralympics, 10000m in 2004, 5000m and 1500m in 2008 but it was as part of the Japanese 4 × 400 m relay in 2004 that he won his only medal, a bronze.[2]
He later moved into administration of wheelchair racing, serving as the race director of the wheelchair section of the 2019 Tokyo Marathon.[3]