In his essay “In Praise of Idleness”, Ber­trand Russell suggested that the working day should be reduced from eight hours to just four. Russell’s intention was not to boost productivity during those four hours (he distrusted efficiency). No, he wanted half as much work to be done and more leisure to be enjoyed. “There will be happiness and joy,” he suggested, “instead of frayed nerves, weariness and dyspepsia.”

Russell’s theory, ironically, holds much better as professional advice than as moral philosophy. He wanted people to work less because work was bad for them. I would argue we should work less because it will make us achieve more. He would be horrified at his idea being recast by the enemy, but his injunction “work less” should be embraced enthusiastically by managers, coaches and businessmen who are trying to get the best out of their charges.

The cult of busyness

Experience tells me that excessive hard work is counterproductive. When I was a professional cricketer, before each season – just before the team got together as a group – I would block out a few consecutive days and dedicate them entirely to practising batting. My only goal was to become a better player, to develop new skills. This wasn’t the humdrum practice that happens throughout the season. This was my selfish time: it was as close as my cricket practice got to a creative exercise.

Which days ended with me batting signi­ficantly better than I started out? The best days followed the same pattern – an intense morning session, around two and a half hours long, followed by a shorter, lighter afternoon session, perhaps lasting an hour or 90 minutes. In total, then, I would do about four hours, just as Russell wanted.

Strangely, when I spent many more hours practising, spreading the work across the whole day, my game stood still or even slightly de­teriorated. Quite simply, you cannot work all day, at least not at a high level. When you are performing near your limits, you use up your psychological resources very quickly. The obvious point follows: stopping practising at the right moment is a vital form of self-discipline, every bit as important as “putting the hours in” and “giving it your all”. There is an optimal amount of work.

This extends far beyond sport. Most writers admit that they cannot write more than about four hours a day, even during a purple patch. They may lock themselves in the study all day long (safely protected from spouse and phone calls) but that doesn’t mean they are writing non-stop. You pedal a bit, then freewheel; even locked in your study, you will be doing this with your mind.

And yet the conventional workplace – the office – condemns the optimal working day as contemptibly slack. Watch carefully the next time someone rushes purposefully past you in the office corridor, shielded from eye contact by the ubiquitous smartphone, radiating the carefully honed “Can’t stop, too busy” expression so characteristic of corporate ambition. They are not rushing to arrive somewhere, still less to achieve anything. They are rushing because rushing is how they display how hard they work.

The cult of busyness extends far beyond grumpy bosses and line managers. It is a cultural malaise. In every area of public life, we demand not only that people work harder, but, crucially, that they be seen to work ever harder. This is the age of professional martyrdom.

Consider the reaction to the “revelations” about David Cameron’s determination to relax. In their biography of the Prime Minister, Francis Elliott and James Hanning describe him like this: “If there was an Olympic gold medal for ‘chillaxing’ he would win it. He is capable of switching off in a way that almost no other politician I know of can . . .

“He tends to get up early, look at the Sunday papers . . . [But then] it’s ‘I’ve absorbed the information, I have taken an action – I will now go into the vegetable patch, watch a crap film on telly, play with the children, cook, have three or four glasses of wine with my lunch, have an afternoon nap, play tennis’.”

Cameron was criticised for taking his job far too lightly or, at the very least, for “bad politics” – as though he should have kept up pretences. Yet workaholism is not remotely correlated with success. If it was, Britain’s two best prime ministers would have been Gordon Brown and Margaret Thatcher. Brown’s exhausted rants are legendary. And though Thatcher boasted about hating holidays and needing only four hours’ sleep a night, one colleague said that at a distance of 12 inches, point blank in the crush of the voting lobby, you saw an exhausted woman. He believes she burned herself out and that her judgement slipped.

Nor should we trust the popularised social science alleging that “geniuses” evolve inevit­ably from 10,000 hours of practice. In his study of talented young musicians in Berlin, K Anders Ericsson asked what separated the outstanding soloists from those who were merely good. The difference was not – as is often misquoted – that the best players practised more. Instead, they practised intensely and then allowed themselves more time to relax and recoup.

Pride and prejudice

The lesser players spread their work throughout the day, never escaping a sense of stress and anxiety. The elite players, in contrast, consolidated their work into two well-defined periods, one in the morning and one in the afternoon. Either side of these peaks of concentration, the best players enjoyed life: they slept more during the daytime and spent more time having fun away from music. Their lives were simul­taneously more relaxed and more productive. What some people call idleness is often the best investment.

The idea that being good at something demands harried, exhausted martyrdom is a relatively new idea. “Only in recent history,” as Nas­sim Nicholas Taleb puts it, “has ‘working hard’ signalled pride rather than shame for lack of talent, finesse and, mostly, sprezzatura.” If we really want to be good at something, we should stop wasting time exhausting ourselves.

Ed Smith’s new column, Left Field, will appear weekly