More and more people are suffering ‘burnout’ – but is this the fault of modern life or is physical, mental and spiritual exhaustion a far older condition? BBC Future investigates.

A few years ago, Anna Katharina Schaffner became the latest victim of the exhaustion ‘epidemic’. It began with a kind of mental and physical inertia – as she put it, a “sense of heaviness” in all that she did. Even the most mundane tasks would sap her of all her energy, and concentrating on her work became increasingly difficult.

Yet when she tried to relax, she would find herself obsessively checking her emails at all hours, as if relief for her ennui would suddenly ping into her inbox. Alongside the weariness came feelings of emotional despondency: “I was disenchanted, disillusioned and hopeless.”

All the commentators represented our age as the most terrible one out there – that it’s the absolute apocalypse for our energy reserves

These feelings will be familiar to countless others, from Pope Benedict XVI to Mariah Carey, who have been diagnosed with exhaustion. If the media are to be believed, it is a purely modern ailment; almost every time Schaffner turned on the TV, she would see a debate on the trials we face in our 24/7 culture. “All the commentators represented our age as the most terrible one out there – that it’s the absolute apocalypse for our energy reserves,” she says.

But can that really be true? Or are periods of lethargy and detachment as inevitable a part of human life as head colds and broken limbs?

A literary critic and medical historian at the University of Kent in the UK, Schaffner decided to investigate further. The result is her new book Exhaustion: A History, a fascinating study of the ways in which doctors and philosophers have understood the limits of the human mind, body – and energy.

There is no doubt that exhaustion is a pressing concern today, with some particularly startling figures emerging from emotionally draining sectors such as healthcare. A study of German doctors found that nearly 50% of physicians appeared to be suffering ‘burnout’, reporting, for instance, that they feel tired during every single hour of the day and that the mere thought of work in the morning left them feeling exhausted. Interestingly, men and women seem to deal with burnout in different ways: one recent Finnish survey found that male employees reporting exhaustion were far more likely to take extended sick leave than burned out women, for instance.

Given that depression also tends to involve lethargy and detachment, some have argued that burnout is just a stigma-free label for the same condition. In her book, Schaffner quotes one German newspaper article that claimed burnout is just a “luxury version” of depression for high-flying professionals. “Only losers become depressive,” the article continued. “Burnout is a diagnosis for winners, or, more specifically, for former winners.”

In general, however, the two conditions are generally considered to be distinct. “Theorists generally agree that depression entails a loss of self-confidence, or even self-hatred or self-contempt, which is not the case for burnout, where the image of the self often remains intact,” Schaffner says. “Anger in burnout is generally not turned against the self but rather against the organisation for which one works, or the clients with whom one works, or the wider socio-political or economic system.” Nor should burnout be confused with chronic fatigue syndrome (CFS), which involves prolonged periods of excruciating physical and mental exhaustion for at least six months, with many patients reporting physical pain at the slightest activity.

According to one argument, our brains are simply ill evolved to deal with the modern working environment. The increasing emphasis on productivity – and the emotional need to prove one’s worth through one’s job – leaves workers in a permanent state of ‘fight or flight’. This state originally evolved to deal with acute danger. But if we face that kind of pressure day in, day out, we endure a steady surge of stress hormones – an onslaught that our bodies struggle to continually fight

For many, moreover, the pressure does not end with work. Cities (and technological devices) are always buzzing with life, and this ‘24/7’ culture can make it difficult to rest at any hour of the day or night. With no chance to recharge our minds and bodies, our batteries are constantly running dangerously low.

That, at least, is the theory.

A build-up of black bile, Galen said, slowed the body’s circulation and clogged up the brain’s pathways, bringing about lethargy, torpor, weariness, sluggishness and a lack of energy

When Schaffner explored the historic literature, however, she found that people suffered from extreme fatigue long before the rise of the modern workplace. One of the earliest discussions of exhaustion was written by the Roman physician Galen. Like Hippocrates, he believed that all physical and mental ailments could be traced to the relative balance of the four humours – blood, yellow bile, black bile and phlegm. A build-up of black bile, he said, slowed the body’s circulation and clogged up the brain’s pathways, bringing about lethargy, torpor, weariness, sluggishness and melancholy. Although we now know it has no scientific basis, the idea that our brains are filled with a tar-like liquid certainly captures the foggy, clouded thinking that many people with exhaustion report today.

By the time Christianity had taken hold of Western culture, exhaustion was seen as a sign of spiritual weakness. Schaffner points to the writing of Evagrius Ponticus in the 4th Century, which described the ‘noonday demon’, for instance, that leads the monk to stare listlessly out of the window. “It was very much seen as a lack of faith and a lack of willpower – the spirit versus the flesh,” says Schaffner. She points out that one monk reported compulsively and restlessly seeking out his brethren for idle chit-chat rather than engaging in useful employment – in much the same way that 21st-century sufferers may find themselves compulsively checking social media.

Religious and astrological explanations continued to abound until the birth of modern medicine, when doctors began diagnosing symptoms of fatigue as ‘neurasthenia’. Physicians now understood nerves transmitted electrical signals, and they believed that someone with weak nerves may therefore dissipate energy like a badly insulated wire. Intellectual figures from Oscar Wilde to Charles Darwin, Thomas Mann and Virginia Woolf were all diagnosed with neurasthenia. Doctors blamed it on the social changes of the industrial revolution, although delicate nerves were also seen as a sign of refinement and intelligence – some patients languished with pride in their condition.

Although few countries tend to diagnosis neurasthenia today, the term is often used by doctors in China and Japan – again, with the occasional accusation that it is an alternative, stigma-free way of labelling depression.

Clearly, many people throughout history have felt just as tired as we do, suggesting that fatigue and exhaustion may just be part of the human condition. “Exhaustion has always been with us,” Schaffner says. “What changes through history are the causes and effects that are aligned with exhaustion.” Back in the Middle Ages it was the noonday demon; in the 19th Century it was the education of women, and in the ’70s it was the rise of rampant capitalism ruthlessly exploiting its employees.

It’s really hard to say that an illness is purely physical, or purely mental, because often it is both at the same time

In reality, we still don’t really understand what gives us that feeling of ‘energy’ and how it can dissipate so rapidly without physical exertion. We don’t know whether the symptoms originate in the body or the mind, whether they are the result of society or created by our own behaviour.

Perhaps the truth is a little of all of these: a growing understanding of the mind-body connection has shown that our feelings and beliefs can have a profound influence over our physiology. We know that emotional distress can increase inflammation and exacerbate pain, for instance – and in some cases it can even bring about seizures and blindness. “It’s really hard to say that an illness is purely physical, or purely mental, because often it is both at the same time,” Schaffner says. In this light, it’s not surprising that our circumstances could cloud our minds and nearly paralyse the body with lethargy. And this fact should in no way suggest the symptoms are imaginary or made up – they may be just as ‘real’ as the fever that comes with flu.

Schaffner doesn’t deny the stresses of modern life. She thinks that it comes, in part, from our greater autonomy, since more and more jobs have given us the freedom to manage our own activities. Without clearly defined boundaries, many people over-stretch themselves. “It mainly manifests in the anxiety of underperformance and a sense of not being good enough – of not living up to these expectations,” she says.

She also agrees that email and social media can drain our reserves. “In a lot of ways the technologies that were meant to save energy have become stress factors in their own right,” she says. Today, it is harder than ever to leave work in the office.

If history has taught us anything, it is that there is no easy cure for this malaise. In the past, patients with neurasthenia might have been prescribed prolonged bed rest – but the boredom often only exacerbated the distress. Today, people suffering from burnout can receive cognitive behavioural therapy to help them manage their emotional exhaustion and identify ways of recharging.

“The cures for exhaustion are subject specific. You have to know yourself what costs you energy and what restores your energy,” Schaffner says. Some people might need stimulation from extreme sports, while others may prefer reading a book. “What’s important is to draw boundaries between work and leisure,” she says. “These are certainly under threat.”

Schaffner herself found that her greater knowledge has helped her ride the peaks and troughs in her own energy levels. “Researching and writing about exhaustion was, paradoxically, quite energising,” she says. “I felt very passionate about the subject, and I also found it soothing to read that so many people during different historical periods had lived through very similar experiences. There is something very reassuring to learn that one is not alone in the way one feels, that others have felt the same – although in different circumstances.”

David Robson is BBC Future’s feature writer. He is @d_a_robson on Twitter.

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