The world is not enough for Karren Brady

Karren Brady has an energy and determination that would daunt even Margaret Thatcher. As vice-chairman of West Ham, she's spent the past months putting together her team's winning bid to take over the Olympic Stadium. She's Alan Sugar's sidekick on

This is immediately clear when we meet in the directors' boardroom at West Ham. Karren, 42, glamorously curvy in a blue silk MaxMara dress under a tight black Valentino jacket, is having her face made up, being briefed by her PA, typing on her computer, eating biscuits and reading text messages on her phone simultaneously. 'I'm a woman, I can do more than one thing at a time because I have to,' she says. 'The worst thing is that it's become an obsession. I now can't just do one thing at a time. If I'm watching TV, I have to be on the computer or doing a crossword as well.' The night before we meet, she attended the Children's Champion Awards, but was worrying about her daughter Sophia, 15, who was cooking dinner for her brother Paolo, 12, for the first time while their father was at a football match. 'I kept ringing to say, "Are you OK? Have you burned yourself?" ' she laughs.

Doesn't she ever feel role strain? 'No, not at all,' she says, looking rather surprised at the idea. 'I can go from doing business with West Ham into filming for The Apprentice and the next day be in an Arcadia board meeting or go and sit in the House of Commons for a debate on something and then come here and negotiate with a footballer. I have the ability to switch.'

Her unbelievably complicated life is made tougher by geography: while her job is in London, the plush, gated family home is in the West Midlands celebrity enclave of Knowle, Solihull, where her children go to school. Karren has a pied-à-terre in Knightsbridge where she lives four days a week, returning home on Thursdays just in time to take over the childcare from her husband, whose job managing Burton Albion football club demands his full attention at weekends. In Birmingham, she throws herself into full-on mummy mode, cooking vast meals, cleaning the house ('I'm a clean freak') and taking her children on expeditions. 'We really don't do anything at the weekend that doesn't involve the family.' Sophia is an aspiring model, who has a contract with Select and can be seen on the Lipsy website sporting scarlet shorts, and Karren is always her chaperone and taxi driver. 'She won't do it if I'm not there,' she says.

All the same, Karren is no pushover as a parent and doesn't use money to compensate for her absence. 'If you continually give in to children, they get petulant and spoilt. I can't think of anything I'd like less,' she says, insisting that her offspring have no idea of the family's wealth (which is substantial: last year she estimated her fortune at £82 million). In London, by contrast, Karren never cooks (she likes to go out to Nobu or Scott's or orders takeaways) and sets no limit on her working day. 'Yesterday, I got up at about 5.30am and got into bed at midnight. And I'll often get text messages in the middle of the night, but that's fine because there's nobody else to wake up.'

I don't think I've ever met anyone with such daunting levels of energy. 'When I was younger it was relentless,' she agrees, 'but now I have to recharge more often. I never used to go on holidays - I used to really hate the packing and the aggravation but I find I do need more breaks.' All the same, she remains welded to her BlackBerry at all times. 'I get 500 emails a day. I'd never catch up if I left it at home.'

Karren is kinder to herself since a routine health check in 2006 revealed she had a cerebral aneurysm (a weakening in one of the arteries in her brain), which could have ruptured at any time. The neurologist she saw told her he was amazed she'd survived childbirth even once. Karren underwent emergency surgery and spent several weeks off work. 'I loathed every minute,' she says. 'I completely understood why being ill makes people want to change their life. They realise they're married to the wrong person or they hate their job. But what I realised was how much I liked my life and that I wanted to do it for as long as possible.' Her brush with death persuaded her to take more risks, she says. 'If someone had suggested to me before that I should do The Apprentice, I'd have thought they were mad. But I thought, "Why not? If you don't like it, or they don't like you, it won't be the end of the world." And I loved the show and I loved Alan.'

She joined the team last year, replacing lawyer Margaret Mountford, and has proved to be one of Sugar's better business decisions. Not only does she add a much-needed dose of glamour to the show, but her cosy straightforwardness is a perfect foil to the camped-up bossiness of both Sugar and his other adviser, former PR consultant Nick Hewer. Has she been asked to play good cop to Nasty Nick's bad one? 'I am more nurturing,' she says. 'I want to take them all home with me and help them. I'm often most impressed by the ones who strut in making ridiculous claims about how wonderful they are, but a couple of tasks in, realise that they need to finesse their style and work as a team to get the most out of the situation. If you want to win, you can't always be looking out for yourself.' In the forthcoming series, she says Jim is 'one to watch. He's a bit of a smooth operator and always remains very calm and collected. And Edward is the accountant who doesn't want to be an accountant. It was quite amusing to see him struggle to break free from the stereotype.' But she won't divulge who wins (the show is entirely filmed in advance).

And how does she get on with Sugar? Can he really be as tetchy as he seems on screen? 'Well, he's very direct,' she says cautiously, 'but actually he's a great family man and a wonderful grandad. He brings his grandchildren in and they're all over him. And his wife Ann is so lovely, you know that the side you see on TV isn't all there is.' This is generous, given their recent spat over the Olympic Stadium bid. West Ham won the backing of Olympic bosses after promising to keep the athletics track in place; Sugar, who used to be chairman of rival bidders Tottenham Hotspur (which wanted to pull the whole stadium down), declared it would be a 'white elephant' and a 'disaster for the taxpayer'.

'Alan was' For once, Karren is lost for words (but I guess livid might fit). 'I said to him, "I can't imagine what you'd be saying to me if we weren't friends." I couldn't believe it!' She taps away at her computer to bring up the Valentine's card he subsequently emailed her, offering free binoculars with every West Ham season ticket. 'Isn't that funny?' she says cheerfully, flaunting what she calls 'the world's thickest skin' that has allowed her to climb unscathed to the top of a sexist profession.

Karren, who has a brother Darren (yes, really), was brought up in Edmonton, just outside the Tottenham stadium, ironically enough. Her father Terry made a multimillion-pound fortune from printing and was once chairman of Swindon Town FC; her mother Rita was a glamorous housewife who had her cigarettes dyed to match her outfits. Karren inherited her father's business acumen: as a child, she was forever coming up with money-making ventures (at the age of six she put up a poster in her bedroom window offering massages to passers-by). 'I was asked to give a speech at my old school, Aldenham in Elstree. They gave me my file and in it were all these letters I'd written to the headmaster with ideas for how the school could make money,' she laughs. 'None of them were ever put into action so we can safely say what he thought of them.'