Defending gold medalist Kristin Armstrong will be the last of 24 cyclists in Wednesday's women's time trial in London.

She will start at 6:04 a.m. Mountain time. The first rider begins at 5:30 a.m. Mountain time and riders start every 90 seconds. The 18-mile course will start and end at Hampton Court Palace.

NBC Sports Network (326 on Cable One, 151 on Dish Network and 603 on DirecTV) will air the event live at 5:30 a.m. Mountain time. NBC will show portions of the event in its late-night coverage at 11:35 p.m.

Armstrong is among the favorites in the race, which also includes Emma Johansson of Sweden, American Amber Neben, Great Britain's Emma Pooley, Canada's Clara Hughes, The Netherlands' Marianne Vos and Germany's Judith Arndt.

Armstrong, Neben and Hughes competed in the Exergy Tour in Idaho in May.

Armstrong, 38, won the gold medal at the 2008 Games in Beijing. She also won the 2006 and 2009 world championships in the event. Armstrong is a University of Idaho graduate who lives in Boise.