The mixed relay is similar to the ordinary relay, but the teams are composed of two women and two men. From its first instance at the world championships in 2005 until the end of the 2017 season, the first two legs were always run by the women, followed by the men on legs 3 and 4. Since the 2018 season however, the race can be started by either the men or women . Additionally, throughout most the events history the women's legs have been and the men's legs as in ordinary relay competitions. However, since the 2019 season the event has been more equitable with all four legs being either or .