Dame Kelly Holmes has said that coming face-to-face with Bear Grylls was by far the strangest thing she encountered in the rainforest on a new TV show.

The Olympic gold medallist is one of the contestants in Bear Grylls: Mission Survive, which sees eight famous faces set out on a tough expedition with adventurer Bear, where one is evicted at the end of each day.

She told TV Times: “I have to say it was quite a surreal situation for us all because we’ve seen him on TV doing crazy things and you go to yourself, ‘This man is an absolute nutter!’ And then you’re actually there with him and he’s asking you to do all these things.

Bear Grylls: Mission Survive
Bear Grylls leads celebrities through the rainforest (ITV)

“I remember on the first day, a helicopter came overhead with Bear hanging onto it, and Jamelia screamed at me, ‘Oh my god, I feel like I’m in a movie!’.”

Dame Kelly added that just because she is sporty, viewers shouldn’t expect her to be fearless: “I have a fear of drowning and we faced water pretty much every day, so I certainly went through it.

Bear Grylls: Mission Survive
Bear lines up the celebrities for Mission Survive (ITV)

“People think when you’re sporty that you’ll be good at everything, but I’m a really, really weak swimmer. I can’t think of anything worse than jumping into water, but sometimes in life you have to face your fears and come out the other side.”

Bear Grylls: Mission Survive begins on ITV on February 20 at 9pm.