The Spandau Ballet and ex-EastEnders star was forced to pull out of the ITV1 adventure show, which is currently being filmed in Norway, after wrenching his back. The Sun reports that producers called on Barnes to immediately join the nine remaining celebrities.
"Being in South Africa did not put him off. He just said, 'When do you need me?', and the reply was, 'Now'," a source said. "He jumped on the next flight and landed in Norway this week.
"Martin had totally crocked himself and was ruled out by the medics. He did something to his back and was crying out in pain. The producers were panicking as they are in the middle of filming."
The insider added: "He's up for all the challenges and is still pretty fit for someone who hasn't played pro football for more than ten years."
The 47-year-old, who also competed in the 2007 series of Strictly Come Dancing, will join the line up which apparently includes actors John Thompson and Sean Maguire, presenter Angelica Bell and hairdresser Nicky Clarke.
It was recently revealed that the second series of the show, which will return to ITV1 later in the year, will be presented by Paddy McGuinness and Georgie Thompson.
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