[2] At the 2008 FINA Youth World Swimming Championships, Knutson won a total of five medals, all of them gold.

[5] In Rome, Knutson swam in the heats of the 4x200 m freestyle relay (with Ariana Kukors, Alyssa Anderson, and Lacey Nymeyer) and won a silver medal after the United States placed second in the finals.

[8][9][10][11] At the 2011 World Aquatics Championships in Shanghai, Knutson won a gold medal in the 4×200-meter freestyle relay with Missy Franklin, Katie Hoff, and Allison Schmitt, with the team finishing ahead of Australia and China.

Her father was a US Citizen and his parents had moved to America from Norway, and her name honors that lineage.

[13] Because of geographic proximity, Knutson used to swim in so many meets in Canada that she was once mistakenly named one of that country's top 12-year-old swimmers.