Rod rocks Penny's world

It's hard not to feel like a dwarf when you stand next to Penny Lancaster. She just goes on, and on, and on - a six-foot-tall streak of toffee. I take my coat off and plonk myself on the chair beside her, a blob in black. She smiles, encouragingly.

Having read of her exploits in the press - her wild public dances to the hits of her boyfriend, Rod Stewart - I have high hopes for Penny. She seems a bit daffy. I have a hunch that she is probably as daft as a brush. Is this the case? "Yes," she laughs, in her warbly Essex twang.

"Friends tell me I was born in the wrong time, that I should have been born in the Sixties. But there's also a side of me that's very insecure, if you can believe that. I was talking to Rod about it only the other night."

What on earth can she possibly be insecure about? In her pale blue TSE Cashmere and grey leggings, she radiates health and energy (albeit in a very skinny way - her thighs are the width of pipe cleaners), and she has an uncommonly pretty girl-next-door kind of a face. She thinks for a while. "It doesn't matter what you look like," she says, finally. "Everyone has parts of themselves that they don't care for. At school, I was bullied; maybe that makes you the person you are. And when I was modelling, I was always being picked and pulled about. You get so many knock-backs." So which bit of herself does she hate? Her feet, apparently. Her toes are all ugly and crunched up - the result of a childhood passion for ballet.

Lancaster is in London (she now lives mostly at Stewart's home in Los Angeles) to promote her new health-and-fitness video and, to be honest, getting her off the subject is pretty tricky. She qualified as an aerobics instructor long before she met her superstar boyfriend, and she has a passion for all things active. She and Rod, she tells me, work out together.

Given that she is 32 and he is 58, this must be pretty, um, interesting. But Lancaster is having none of it. Although she recently admitted that she sometimes accidentally referred to Rod as "Dad", and she once said that he couldn't keep up with her twice-daily demands for sex, today she is unstintingly loyal and loved up, the human equivalent of a Hallmark card. "He plays football twice a week," she says, admiringly. "So we keep each other going."

Lancaster met Stewart in 1998, at the Dorchester hotel. Stewart was in the process of separating from Rachel Hunter, the mother of his two youngest children; Lancaster was living with her boyfriend of 10 years, Micky Sloan, a City trader. A friend dared Penny to ask for his autograph. As she did this, she revealed that she was a photography student at Barking College and that
she would like to take his picture. He invited her to his concert at Earls Court the next day. After the concert, she did not hear from him for nine months. Then, one day, she got a telephone call at the home she shared with Micky in South Woodford, east London. Stewart asked her to have dinner with him; she agreed. A month later, they went to Spain together. By the end of that week, they were a couple (despite her admitting to him that she did not own any of his records). She came home, broke the news to Micky and has been in and out of the tabloids ever since.

Does she mind being known only as Rod Stewart's girlfriend? To my amazement, she doesn't bother droning on about her career or her sense of herself. "No!" she says, simply. "It's a wonderful thing. It doesn't worry me at all. But it is still bizarre being in the papers all the time. Rod's a legend. He's used to it; it built up gradually, while I was thrown in at the deep end. But I'm very connected to who I am. I still think of myself as an Essex girl. What's great is that Rod has a lot of friends from back home. He's very grounded. He plays his football, he goes to the pub. That's the best side of our lives. Of course, when I see him on stage, it's like: 'OH MY GOD!' I'm so proud.

All those thousands of people watching him. His fans are lovely, coming up to me and chatting."

From the outset, the press made much of Lancaster's putative rivalry with Hunter, suggesting that Penny had dyed her hair blonde and was wearing ever-shorter skirts in order to look like her predecessor (and then there was the incident at an awards ceremony in Monte Carlo, when Penny strutted her stuff to the strains of Do Ya Think I'm Sexy, after which Rachel apparently stormed off in a huff). Lancaster, however, is too discreet to discuss this. "You see one headline after another and you just think, 'Oh well, there they go again.' I'm used to it."

What of her role as stepmother? (As well as Renee and Liam, his children by Hunter, Rod has a daughter, Ruby, whose mother is Kelly Emberg, and two grown-up children, Sean and Kimberley, from his marriage to Alana Hamilton.) Was this daunting?

"I've never wanted to step into the shoes of their mum. But family life is great - it's what I miss about home. We do lots of things together. It could have been daunting, but it happened gradually. I never forced myself onto them. I was very aware of what a delicate situation it could be. Children are very intuitive - they pick up on vibes - so I was just myself, and they grew to accept and love me."

But still, she misses home. "My life is with Rod, and his kids are in LA, but it's not a place that I fit into. We have a lovely house and the weather is great, but I'm terribly homesick." When she returned to Rod's mansion near Epping last week, her heart leapt at the sight of a proper British autumn.

Rod, she tells me, is everything a girl could want in a man. "He believes in what I do. He knows that I'm passionate and talented in the areas I work in. I've just done the publicity photographs for his new album, and it was great working with him. He's more relaxed with me, so you get nicer shots. It's the whole package that I love. He's romantic, thoughtful, supportive and protective of me. I'm madly in love."

The age difference, she insists, is an irrelevance. "It's about people's vitality. You can find younger guys who are very sedentary and boring, with no sense of humour. Rod's got a great sense of humour. We're always laughing."

Stewart has said that he will never marry again, and has hinted that he is not keen to have more children.

Does Lancaster want a family of her own? Does she dream of a big, white rock-star wedding? "There's plenty of time for all that," she says, adroitly. "At the moment, I want to concentrate on my career. The important thing is to have the love and support of a partner."

Her own parents, Sally, a hospital administrator, and Graham, a City lawyer (who is only a year older than Stewart - though the two get on famously, according to Penny), split up after 25 years together when their daughter was 18. At the time, this pretty much dented her belief in the idea of marriage.

"Initially, I thought, 'Well, that's it. If Mum and Dad can't make it last, no one can. What's the point?' I don't feel so much like that now. I dream about Rod and me always being together. But the marriage side of things, that's not so important. Love, and your health; all the other stuff comes second. There couldn't be anything more important to me than him." But back to the video. Lancaster tells me that her philosophy has nothing to do with losing weight and everything to do with looking good. Follow her routines - including a salsa dance she has devised called The Jackson - three times a week, and you'll have yourself a fabulous new body.

What about diet? I cannot believe she is a devotee of cream cakes. She begins by saying that a girl should allow herself the occasional treat, and ends by admitting that she has all but renounced red meat, dairy products, bread and pasta. I get up to leave her PR's office feeling rather depressed - greedy as well as dwarfish. Penny, however, is already bouncing up and down, happy to tell the next person who's ready to listen all about her extraordinary man.

Ultimate Body Workout with Penny Lancaster is available for £14.99 (DVD) or £12.99 (VHS) at all good video stockists and from our shopping channel (see below).