Born in Northwich, Cheshire, in 1973, Radcliffe started running early, and at age 11, after her family moved to Bedford, she joined the Bedford & County Athletics Club. When she was 16, she competed at the World Cross Country Championships. She continued to pursue running and chose to devote herself full-time to the sport after graduating from Loughborough University in 1996 with a degree in modern languages. She'd already won the junior race at the 1992 World Cross Country Championships. She later won the World Half Marathon Championships in 2000 and 2001 and long-course titles at the World Cross Country Championships in 2001 and 2002.

In her marathon debut, in 2002, she won the London Marathon. Later that year, she set a world record of 2:17:18 at the Chicago Marathon. Returning to London in April 2003, Radcliffe smashed her own record, finishing in 2:15:25, a world mark that would stand until 2019. 

Between 2002 and 2008, she won three London Marathons (2002, 2003, 2005), three New York City Marathons (2004, 2007, 2008), a Chicago Marathon (2002), and a World Marathon Championship (2005). She represented Great Britain at the Olympics four times in a row (1996 to 2008).

She also picked up the prestigious MBE, or Most Excellent Order of the British Empire, in 2002—the same year the BBC named her its Sports Personality of the Year. When Radcliffe retired from competition in 2015, she did so in fitting fashion, high-fiving fans on the streets of London as she completed one last 26.2-miler.

Radcliffe shared her remarkable story in 2004’s Paula: My Story So Far, a memoir she followed with 2011’s How to Run: From Fun Runs to Marathons and Everything in Between. She has appeared on Who Wants to be a Millionaire? and is a passionate advocate for a clean sport.