Groberg attended the University of Maryland, College Park (UMD) and competed in varsity track and cross country. In May 2006, Groberg graduated from UMD with a bachelor's degree in criminology and criminal justice.
Groberg entered the Army and attended Officer Candidate School at Fort Benning, Ga. He received his commission as an infantry officer, Dec. 4, 2008. After completing Infantry Officer Basic Course, Mechanized Leaders Course, U.S. Army Airborne and U.S. Army Ranger Schools, he was assigned to the 4th Infantry Division at Fort Carson, Colo., as a platoon leader.
In November 2009, he deployed to Afghanistan as part of Task Force Lethal, with responsibility for the Pech River Valley in Afghanistan's Kunar Province. Upon returning home in June 2010, he continued serving as a platoon leader until he was reassigned as an infantry company executive officer from October 2010 to November 2011. He was then assigned as the brigade personal security detachment commander for 4th Infantry Brigade Combat Team, 4th Infantry Division. He deployed again to Kunar Province, Afghanistan, in February of 2012, with Task Force Mountain Warrior. He was promoted to captain in July 2012.