The MP has kept this such a closely guarded secret that it is news to even his long-standing press adviser. For three years, from the age of 14, Edward Balls was a campanologist, pulling the ropes of the church bells in a Nottinghamshire village. In his office in the Commons, Balls offers a physical demonstration, with full hand gestures, of bell-ringing, including when to let the rope go so you don't crash through the belfry.
So what's his advice to the Culture Secretary? "You should always check the bells. A good campanologist would always check the bells. Poor Jeremy. 'There but for the grace of God go I,' is what every bell-ringer would say in those circumstances."
Besides his duties as an MP and member of Ed Miliband's Shadow Cabinet alongside his wife, Yvette Cooper, this year Balls has run a marathon and learnt to play the piano (he reveals he passed his Grade 1 last week, unashamed that he was sitting it alongside children). He is often on Twitter boasting about his cooking skills, including 12-hour barbecues and his handmade, intricately-designed birthday cakes for his children. Is the 45-year-old politician undergoing a mid-life crisis?
"Absolutely," Balls says. "It's definitely a mid-life crisis. Yvette's view was that if you're going to have a mid-life crisis, you might as well manage it well and enjoy it as much as you can. And luckily it does not involve motorbike helmets and mad disappearances to Morocco. I've not attempted to cross Africa in a canoe. I'm doing Grade 1 piano, I ran a marathon, and it's fabulous, I'd recommend it."
Is there nothing he can't do? "There's nothing I can't do in an amateur way."
There are serious issues to discuss, on the economy, and the future of the Labour Party, but, hours before Friday's Olympic opening ceremony, it is hard to escape the mood of joyous anticipation around the capital, and Balls is also in good humour. He, Yvette and their three children have tickets – that they bought themselves through the ballot system – for the women's 10m diving final, but he's worried that their seats are so far back that they might not be able to see the competitors leave the boards, only hit the water.
Let's put this as politely as possible: Balls used to be at the non-athletic end of the spectrum. But, after his marathon training (he did it in a respectable five and a half hours) he seems to have kept at bay the infamous "parliamentary stone", the weight that MPs gain in their first term. Balls's other sport is goading David Cameron and George Osborne across the Despatch Box.
This is usually all part of the Commons rough and tumble, accompanied by jokes. Back in November, when The IoS last interviewed Balls, the MP encouraged talk of a "bromance" between him and Osborne, describing the Chancellor as "the best politician in the Conservative Party at the moment".
But, earlier this month, Osborne alleged Balls was "clearly involved" in the Libor interest rate-fixing scandal, a comment which triggered one of the most hostile exchanges at the Despatch Box in recent years. There were no jokes, and the Chancellor accused Balls of "smearing his way through the last 13 years" of front-line politics.
Balls confirms that the "bromance" is over: "When the economic debate was publicly seen to be more in the balance, when George Osborne's stance at Treasury questions was 'I'll be proved right, you'll be proved wrong, and the egg will be on your face', I think he found it easier at that time to smile and joke.
"But I guess you find out people's characters when they're under pressure. As it has increasingly become clear that on the economy he's got it wrong, on the Budget he's got it wrong,on the political strategy he's getting it wrong, I guess he has found it harder to maintain a cordial demeanour. "Since the recession has deepened and since the Budget, the atmosphere has changed. You judge people's character by how they act in difficult times."
Last week's GDP figures were worse than the Government or the IMF expected, with the economy shrinking by 0.7 per cent between April and June, but the Chancellor and Prime Minister have insisted they will not change their deficit-reduction strategy.
Balls says Britain will pay a "very he avy long-term price" for the Government's refusal to change tack and stimulate the economy, which he claims will end up "permanently weaker" as a result.
Balls says he still believes that Vince Cable, the Business Secretary, who last week claimed he would "probably" make a good Chancellor, regards Osborne's Plan A as "deeply foolhardy", but adds that the Liberal Democrats are locked in a political and economic "tragedy".
What about his own leader, Ed Miliband? "Ed has been able, on the economy, on phone hacking, to set an agenda in opposition. Tony Blair and Margaret Thatcher did not manage to set the agenda in 1994-5 or 1976-7 in the way Ed has done in the last year.
"People are starting to say, 'Actually, I can imagine him being Prime Minister'. That is a big achievement. Labour's still got more work to do – we have a long way to go.
"I think Ed can enjoy the Olympics, have a holiday, come back in September knowing that he has got us into a better place, and we've got ourselves into a better place together than anybody thought could be done in half a parliament."
As economic adviser to Gordon Brown when he was Chancellor, Balls famously opposed Britain's entry into the euro. But not everyone in the Shadow Cabinet agrees. If Ed Miliband were Prime Minister for long enough, would Britain adopt the single currency? "I don't think that joining the euro is remotely on the agenda of any foreseeable Labour government. I don't think you'll find Ed Miliband or [the shadow Foreign Secretary] Douglas Alexander disagreeing with that for a second."
To listen to Balls, you would think that the Labour Party was united from top to bottom, but it is not. There remains distrust from Blairites of the shadow Chancellor, and of the leader, while speculation continues that Cooper, rather than Balls, is being lined up as the next leader if Miliband fails. Balls himself still struggles to shake off his closeness to Gordon Brown. An intern of Balls, at his own leaving party last week, sang a karaoke version of The Stranglers' classic "Golden Brown", but replacing it with the name of the former Prime Minister, and those present say Balls enthusiastically joined in the mockery.
Balls seems shocked that the gossip has leaked out, and refuses to talk about it, on or off the record, apart from saying: "What happens in the karaoke room stays in the karaoke room, isn't that the phrase?"
Balls is later off to a piano lesson – he's now studying for his Grade 2. The man Cameron described as a "muttering idiot" fits in 15 minutes every day to practise instead of listening to Thought for the Day and before the "madness" of getting the children to school.
It is "really therapeutic": "There are some things which you can do while thinking of other things. You can drive on a car journey and practise a speech, or you can lie on a beach and worry about the future of the country, but the thing about piano playing is – especially if you're new to it and you've got two hands and look at the music – if your mind thinks about anything else, you just lose it." If this really is a mid-life crisis, Balls seems to be relishing it.
Curriculum vitae
25 February 1967 Edward Michael Balls is born to Michael Balls, a zoologist, and his wife Carolyn, a chocolate factory worker, in Norwich, Norfolk.
1978 He attends the private, all-boys Nottingham High School.
1983 Joins the Labour Party.
1988 Graduates from Keble College, Oxford, with a first in PPE. While at Oxford, he was a member of the Tory, Liberal and Labour Clubs.
1989 Kennedy scholar at Harvard University.
1990 Joins the Financial Times as a writer.
1994 Becomes an economic adviser to the shadow Chancellor Gordon Brown. He helps to rewrite Labour's economic strategy, aiding New Labour in ditching the old tax-and-spend image.
1998 Marries Yvette Cooper, now shadow Home Secretary, in Eastbourne. The pair eventually become the first couple to serve together in the Cabinet.
2005 Elected MP for Normanton.
2006 Becomes Economic Secretary to the Treasury.
2007 He is promoted to Secretary of State for Children, Schools and Families, after Brown becomes Prime Minister.
2010 Wins the new Morley and Outwood seat in the General Election.
2010 Comes third in the Labour leadership contest, behind Ed and David Miliband. He is appointed shadow Home Secretary.
2011 Becomes shadow Chancellor of the Exchequer.
Jess Baldwin
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