Since this blog has recently had to be less than complimentary about some of President Obama’s economic policies, it is only fair that we balance the books by defending him against some particularly stupid criticism.

Idiots with no sense of priority – and probably no experience of proper work – have been complaining about the President playing golf and taking holidays.

Those of us who understand decision-making processes would be far more worried if he was not taking time to relax and get out in the fresh air.

The ancient Roman poet Juvenal was wise to commend “a healthy mind in a healthy body”. Modern scientists have uncovered a mountain of evidence confirming that a healthy mind, fit for making decisions, is indeed far more likely to be maintained by a healthy body than by one in a permanent state of fatigue.

For any decision-maker, from the self-employed small businessman to the Chief Executive of the most powerful nation in the world, long hours are simply a waste of time unless they are directed by good judgment.

Such judgment is measurably better if you make sure you have frequent breaks, a balanced diet, regular exercise, a sensible working day, and six to eight hours unbroken sleep every night.

There may still be times when you are called on to do 24-, 48-, or even 72-hour shifts, usually without notice in a crisis situation. Yet, to quote our hero Bill Slim again, the best preparation you make for such situations is to make sure that you are fit and well rested when they begin. They are often impossible to predict, and it is obviously very dangerous if they happen to occur when the decision-maker is already suffering from the effects of mental and physical exhaustion.

There is a macho culture that demands people are seen to be working hard – but there is a difference between working hard and working effectively.

Of Mr Obama’s predecessors, none had a stronger work ethic than Jimmy Carter – but the abiding image of Mr Carter’s Presidency was of him collapsing on a run, which seemed symbolic of the failure of his Administration. Ronald Reagan, on the other hand, made a point of going to bed early and was often called “lazy” – at least relative to the exacting standards of his office – but he always gave the impression of being remarkably fit for a man of his years, and he is generally accounted a successful Chief Executive, since he achieved all the objectives he set himself.