McCullough returned to the cross country and track & field squads after a successful running career with the Tiger program from 1996-99. McCullough was an NCAA II All-American and five-time Academic All-American while competing for the Tigers during that span. The four-time national qualifier also earned five all-conference awards while competing in the Rocky Mountain Athletic Conference, known for its national-caliber distance running reputation. He led the Tiger cross country squad to a 10th-place finish at the NCAA II meet in 1997, its highest finish since joining NCAA Division II.

McCullough spent two seasons at Thomas More Prep-Marian High School as the head cross country/assistant track & field coach from 1999-2001. He served as a volunteer assistant with the FHSU track & field squad during the 2001-02 seasons.

The 1999 FHSU graduate has also been active in the area running community, serving as both a race director and running club coordinator since graduating from FHSU.

McCullough also works in the Health and Human Performance department as an instructor. He earned a bachelor degree from FHSU in English in 1999 and completed a master degree in Sports Administration in 2001. He completed a second bachelor degree in Spanish in May of 2005. He had also spent the past six years in the FHSU Sports Information Department, where he worked as the head Sports Information Director for three years.

McCullough is just the fourth cross country coach in the 57-year history of the program. McCullough resides in Hays with his wife, the former Karen Kreutzer, and their son, Elijah.