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Jill Douglas introduces day four action from the track cycling world championships in Ballerup, Denmark. Between 1896 and 1956 the Danes hosted the world championship nine times and the venue, north of Copenhagen, is steeped in history.

There are three gold medals up for grabs and British eyes will be trained on Olympic champion Victoria Pendleton, who is going for glory in the women's sprint. She has been world champion in this event four times in the last five years and claimed the title last year in thrilling fashion, defeating her Dutch rival Willy Kanis in a photo finish in the deciding race.

Great Britain's Lizzie Armitstead is likely to be going for gold in the women's omnium, which is described as pentathlon on wheels and will become an Olympic event in 2012.

In the men's madison, home favourites Michael Morkov and Alex Rasmussen are the defending champions after easily beating British sprint sensation Mark Cavendish, who could only finish sixth with partner Peter Kennaugh in Poland last year.

Hugh Porter and Chris Boardman are the commentators.