Guðbjörg Jóna Bjarnadóttir gained her first international experience in 2017 when she won the silver medal in the 200-meter run behind the Maltese Charlotte Wingfield in 24.13 s at the Games of the Small States of Europe (GSSE) in Serravalle and also over 400 meters she won the silver medal in 55.72 s, this time behind the Cypriot Christiana Katsari . In addition, she won the 4-by-100-meter relay in a new game and national record of 45.31 s and also in the 4-by-400-meter relay she won in 3: 47.64 minutes. Then she finished fifth in the 100 and 200-meter run at the European Youth Olympic Festival (EYOF) in Győr in 11.78 s and 24.06 s respectively. The following year, she won the U18 European Championships there in 11.75 s in the 100-meter run and won the bronze medal over 200 meters in 23.73 s. In addition, she was eliminated with the 4 x 100 meter relay in the lead. In autumn, she took part in the Youth Olympic Games in Buenos Aires over 200 meters , where she won the gold medal, setting a new national record in a run of 23.37 seconds. In 2019 she won the GSSE in Bar in 11.79 s over 100 meters and in 24.26 s also over 200 meters and won the silver medal behind the team in 45.96 s with the 4 x 100 meter relay from Cyprus. Then she reached fourth place in 23.64 s at the U20 European Championships in Borås, Sweden .
Bjarnadóttir became the Icelandic champion in the 400-meter hurdles in 2016 and in the 200-meter run in 2018 and 2019. In 2018, she also won the 4 x 100 meter relay. In 2019, she became a champion in the 60-meter run and over 200 meters in the hall.
Personal bests
100 meters: 11.56 s (+0.6 m / s), June 29, 2019 in Mannheim ( Icelandic record )
60 meters (hall): 7.47 s, March 2, 2019 in Hafnarfjörður ( Icelandic record )
200 meters: 23.45 s (+1.9 m / s), June 16, 2019 in Selfoss ( Icelandic record )
200 meters (hall): 23.98 s, February 14, 2016 in Reykjavík
Note: Icelanders are referred to by their first name or first and last name, but not just their surname. Further information can be found under Icelandic personal name .