Brown hires personal trainer as he gets fit for leadership fight

But rather than slumping in an armchair at his holiday cottage in Suffolk, the Prime Minister is digging deep and has decided the time has come to get in shape.

Needing all his strength for his return to Westminster at the end of the month and amid increasing talk of a leadership challenge, the PM has hired a personal trainer.

Getting in shape: Gordon Brown is having gruelling daily sessions with a personal trainer during his holiday so that he is fighting fit for his return to Westminster

Millie Dobie, a £50-an-hour health coach, has the unenviable task of visiting the Premier every day at 7.30am to drag him on runs around the countryside.

Mr Brown, 57, dons shorts and t-shirts for the daily sessions with the blonde, who is in her 40s, before breakfast with his family.

She is said to take him through the woods and fields, jumping over logs, as his bodyguards trail behind before putting him through exhausting toning exercises.

The PM is understood to be desperate to get fighting fit before his return to London,  when he is set to face the toughest period of his premiership so far.

Perhaps the contrast to potential leadership rival, David Miliband - who, at 43, is 14 years his junior - has also focused his mind on his physical abilities.

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'Millie is making him work hard. She's got him jumping through hoops. It's quite a sight. She's very slight and nimble,' a source told the Sun.

'If Gordon's ever flagging, Millie just shouts at him to keep up and pushes him harder and harder. Poor thing. He looks worn out when they've finished - and so do his minders.'

Miss Dobie was recommended by film director Richard Curtis and his wife Emma Freud who held a dinner party for the Browns this week, according to the paper.

Asked yesterday about her new client, she said: 'I'm not supposed to talk about it. I'd have to clear it with Number 10.'

The Prime Minister played rugby as a teenager but lost the sight in one eye during a game at school. He is also said to be a regular at the Westminster gym.