[11] Lopez Lomong and his family belong to the Buya (also spelled Boya) ethnic group of southeastern South Sudan, who speak the Laarim language.

Although he originally assumed his parents had been killed by the Sudan People's Liberation Army, he was reunited with his mother and family, who now live outside Nairobi, in 2003.

Since his selection as flagbearer he has been careful not to criticize China directly, choosing instead to focus on the inspirational side of his story.

"The Olympics are supposed to bring people together to peacefully blend and I'm looking forward to that and stepping on the track and wearing my colors and representing my country."

In June 2010, Lomong repeated as men's champion by winning the 1500 at the 2010 USA Outdoor Championships in a highly tactical race.

He secured a slot for the 5000m finals after winning his preliminary heat in 13:42.81, just ahead of American record holder Bernard Lagat (13:42.83).

[19] In the finals, he placed 3rd behind winner Galen Rupp and runner up Bernard Lagat to secure a spot on his second Olympic team.

[22] Lomong was part of a strong American performance, with fellow countrymen Bernard Lagat and Galen Rupp placing 4th and 7th, respectively.

[24] Lomong surpassed the previous indoor 5000m American Record held by Bernard Lagat at the Armory's last chance meet with a time of 13:07.00.

[25] Lomong won the 1500 metres in 3:43.09[26] at the USA Indoor Track and Field Championships at the Albuquerque Convention Center in New Mexico.

[27][28] Lopez finished 3rd running 3:39.11[29][30] at USA Outdoor Track and Field Championships in Sacramento, California on June 28.

[31] On March 1, Lomong finished 8th in the mile at USATF Indoor Championships hosted at the Reggie Lewis Center, Boston, MA.

[32] In June, Lomong finished 6th in 13:53.64 in 5000 meter at USATF Outdoor Championships hosted at Hayward Field, Eugene, Oregon.

In June, Lomong won the USATF Outdoor Championship in the 10,000 metres at Drake Stadium, Des Moines, Iowa.

On August 3, Lomong won 2018 Sir Walter Miler in 3:53.86 in the same race John Gregorek Jr., Sam Prakel, Patrick Casey, Ben Blankenship, Craig Engels, Sean McGorty, Hassan Mead, Charlie Marquardt, Robert Domanic, Graham Crawford, Jacob Thomson, Cristian Soratos ran under 4:00.