The greatest boxing comeback of all time?
28 November 2016 Last updated at 12:22 GMT
World champion boxer Vinny Paz had two titles when he broke his neck in a near-fatal car crash in 1991.
Mr Paz describes on the Today programme how he ignored all medical advice and secretly started training again, eventually winning three more world titles.
His story is told in the film Bleed for This, produced by Martin Scorsese.