There’s a moment, as I sit down with Rebecca Adlington, when the notion of what we are about to do seems really quite absurd. Okay, so she is the first British woman to win an Olympic gold medal in swimming since Anita Lonsborough in 1960. Okay, so she’s the first British swimmer to win two Olympic gold medals since 1908. Okay, so she’s our most successful Olympic swimmer in 100 years. But she is, also, just 19!

What if that’s it? What if all that glitters is the gold? How do you connect with a girl who has spent most of her life in chlorine, dreaming of Jimmy Choos?

We meet on a pleasant Friday morning at a posh hotel in London. She seems smaller and more vulnerable than she appeared in Beijing and my apprehension is palpable. I fidget with the recorder, fumble my notes and apologise for not being a swimming correspondent. I open with a lame inquiry about life since the Olympics and she comes rolling at you like a biblical tidal wave.

First, Oh My God, there was a two-week Mediterranean cruise with her boyfriend, Andy. “I absolutely lovvvvved Venice,” she enthuses, with a lovely Mansfield lilt. “It’s just my favourite city.”

Then, Oh My God, there was the invitation to watch her friend, Mark Foster, on Strictly Come Dancing. “I was like a kid at Christmas,” she insists. “I have watched every series of Strictly since it started and to actually be there, so close that I could almost touch them, was sooo much fun.”

Next, Oh My God, was the invitation to The Pride of Britain awards and the chance to rub shoulders with Richard Branson and Vernon Kay. “I was shocked with how genuinely nice they were,” she gushes. “Richard Branson blew me away because he was so lovely. I was like, ‘Hold on! You’re worth absolutely millions and you’re sat here talking to me! And I lovvvvve Vernon Kay. He is probably one of my favourite celebrities and I was so in awe of him.”

After that, Oh My God, there was the invitation to take on her mother on Ready Steady Cook. “In the past I’ve watched all these programmes on TV and thought, ‘Oh My God, that looks so much fun’ and I never thought I’d be invited. Ainsley Harriott was just so nice. He was absolutely lovely.”

And then, Oh My God, there was the fabulous Sports Aid ball where she was presented with a Tiffany necklace for the evening (“It was so gorgeous, I didn’t want to take it off”), entertained by Bradley Wiggins (“He was so funny he should have been a comedian”) and marvelled at the bids in the charity auction. “I couldn’t believe how much they were going for; I was like, ‘Oh My God, that’s what I paid for my car!”

And that’s just for starters. She has had a private audience at No 10 with Gordon and Sarah Brown, a day as a guest starter at the Great North Run, a ticker-tape reception at the athletes’ parade in London and, Oh My God, an audience with the Queen. She has enjoyed and embraced every moment.

“What stands out?” I ask.

“The Pride of Britain Awards,” she says. “That was the night I realised who the true heroes are. We’re Olympians, fair enough, we represent our country but we are doing something we love and would do, regardless of the recognition, but this was completely different. I gave an award to Liam Fairhurst, an incredible boy. He was diagnosed with cancer in his leg when he was 10 and became best friends with this other boy, Jack, in hospital.

“Unfortunately, Jack died. Liam decided to honour his memory by swimming a mile to raise money to build a caravan park in North Yorkshire, for cancer patients to have a holiday. A mile is a lot of lengths for someone who has lost three-quarters of their thigh muscle to cancer. Liam was the one that touched it for me. I thought he was unbelievable.”