Lennart Lindroos, a breaststroke swimmer from Helsinki, advanced to the semi-finals at the Stockholm Olympics in both, the 200 and 400 metres. Domestically he was more successful in the backstroke, winning the 100 metres at the Finnish championships in 1911 and 1912, having won the 200 breaststroke in 1910. In 1911, Lindroos set a Finnish record for the 100 metres backstroke with 1:36.4. The record remained unbroken until 1916. By profession he worked as a janitor and machinist, but died after a long illness at the age of just 35 years.