Career
During his sporting career, Gudmundsson swam for the club Sundfélag Hafnarfjarðar, and later represented Iceland at the 2000 Summer Olympics. Gudmunsson competed in the men"s 100 m breaststroke at the 2000 Summer Olympics in Sydney. He challenged seven other swimmers in heat four, including two-time Olympians Valērijs Kalmikovs of Latvia and Arsenio López of Puerto Rico.
Entering the race with a fastest-seeded time, he faded down the stretch to touch the wall for a sixth spot in 1:05.55, a 1.5-second deficit from joint leaders Kalmikovs and Lopez (a matching time of 1:0402).
Gudmundsson placed fifty-second overall on the first day of prelims.
