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Woman running across America in 42 mile daily chunks

19 June 2012 Last updated at 16:45 BST

British civil servant Jennifer Bradley has taken up the challenge to run across America in 80 days.

That means running 42 miles every day.

Ms Bradley spoke to BBC Radio 5 liveUp All Night from Montana, 900 miles into her 3360 mile journey.

To listen to other 5 live interviews, please visit the Best Bits page.