Lennart started to dance Swedish style jitterbug at Lasse Kühlers dance school in 1980 and became a member of recently formed Swedish Swing Society in 1981. In the early years he competed frequently at different places around Sweden and he also spent lots of hours dancing socially. Around this period of time he furthermore became a member of the board of above mentioned society and was also an active part of organizing the very first Herräng Dance Camp in August 1982. After getting his first impressions of African-American swing dancing in 1983 he was hooked and turned into becoming one of the pioneers of the first modern revival of lindy hoppin'. In 1984 he travelled to New York to meet and study with the late Savoy dancer Albert Minns, whom he later on the same year also invited to Stockholm for teaching and lectures. After mister Minns' visit Lennart together with a few dance friends formed Swedish swing dance company The Rhythm Hot Shots (later Harlem Hot Shots) in 1985 and started to study old film clips to learn more about not only the lindy hop but also the charleston, tap, acrobatics and other things related to the African-American swing dance tradition. Gradually these studies lead to that the company started to perform and teach and later on also to become professional. In 1986 Lennart got in contact with Frank Manning and in 1987 mister Manning was for the very first time invited to Stockholm to work with the company.
When The Rhythm Hot Shots started to receive some international recognition during the early 90s, Lennart was one of the main dancers. The company travelled extensively throughout the decade and was among a handful of other dancers and organizers an active part of bringing the dance back into some kind of limelight. At the same time as being a dancer in the troupe, Lennart also started to do lots of administration (especially for the Herräng Dance Camp which The Rhythm Hot Shots had become an active part of back in 1989), research, film productions et cetera. In year 2000 he was a part of introducing the lindy hop to Russian dancers and in 2004 he opened swing dance studio Chicago in central Stockholm.
Lennart recently left the Harlem Hot Shots but he still travels teaching on an international basis and occasionally performs. During the Swedish summers he is one of the main characters and workers at the Herräng Dance Camp and for the rest of the year he is seriously involved in the Chicago dance studio project.