He graduated from University of Southern California in 2012 with a degree in Public Administration and Social Service Professions and is currently[when?]

A native of Los Angeles, California, Nellum attended Long Beach Polytechnic High School, where he also competed in American football as a wide receiver, and was teammates with Terrence Austin, Jurrell Casey, Vaughn Telemaque, and Donovan Warren.

In his sophomore year, Nellum finished second to David Gettis in the 400 meters at the 2005 CIF California State Meet.

[2] In a memorable 200 metres dash, Nellum (state meet record 20.43) ran head-to-head with 100 meters champion Jahvid Best (20.65), narrowly beating him down the stretch.

2 among high school sprinters in 2007, and earned Nellum a consecutive All-USA selection by USA Today.