In Sweden almost everyone participate in youth sport at one time or another. In recent years, however, overall participation rates have declined and many stop early. The aspiration of the sport confederation as well as the Swedish state is that young people should stay longer in sport which raises questions about participation patterns during adolescence, the ease of joining a sport club, and the barriers to remaining a participant. Drawing on a nine-year longitudinal study, this article reports on the participation patterns among a group of 241 youth that were followed from 10 to 19 years. They took part in four surveys (when they were 10, 13, 16 and 19 years of age). The results show a clear polarisation, one fourth did not take part at all or had only participated for a short time, one fourth participated all the time from the age of 10 to 19. Few started after the age of 10. The pathways for those continuing were characterised by diversification and not specialisation.