Career
On 5 July 2014 she broke the world record in the 50 meter butterfly (long course) with a time of 24.43. The large margin of 0.64 seconds by which she broke the old record has been compared with Bob Beamon"s 1968 long jump world record. On 22 March 2008, at the age of 14, she took the gold medal in women"s 100 m butterfly at the 2008 European Aquatics Championships in Eindhoven, Netherlands.
She was clocked for 58.44 seconds.
In the semi-finals the day before, she set a new national record with 58.38 seconds, breaking Anna-Karin Kammerling"s old one (5871 seconds). At the Swedish championships in 2008 she swam at 58.55.
On 26 July 2009 at the 2009 World Aquatics Championships Sjöström set a world record in the semifinals with a time of 56.44, surpassing Inge de Bruijn"s nine-year-old record. (The European Aquatics Championships is a biennial event and hence did not take place in 2009)
In 2015 she was awarded the Victoria Scholarship.
At the 2012 Summer Olympics in London, Sjöström competed in four individual events, reaching the semi-finals of the 50 m freestyle, 100 m freestyle and 200 m freestyle, and finishing 4th in the final of the 100 m butterfly in a time of 57.17.
Sjöström"s world record was broken in this race by Dana Vollmer of the United States. Long course (50 m)
Short course (25 m)
Only individual
She also participated in the 2008 Summer Olympics and finished 27th in the 100 metre butterfly and 29th in the 100 metre backstroke. She also participated in Sweden"s 4×100 metre medley relay team
They managed to reach the final, but in the final they were disqualified for an over-long false start.