The fatigue that office workers experience at the end of the day is legitimate.

Office workers are often ridiculed for having an easy job. “Sitting the day away” sounds easier than a literal walk in the park and yet, after 8 hours of typing, answering emails, reading, Excelling, Wording, and PowerPointing, people still experience fatigue. How is this possible?

The director of sleep medicine at Lenox Hill Hospital, Dr. Steven Feinsilver, explains that our hearts will pump and adrenaline will be produced whenever we’re stressed. It’s a fact that the human body reacts to both physical and mental stress, not just physical stress. We need to realise that the human brain is physically working all the time - just because the brain’s physical movement isn’t as visible as swimming or jumping, we assume that there’s no exertion. But there is. The kind of exhaustion you feel after sitting and concentrating from 9-5 is obviously different to the exhaustion you feel after a gym session or building a brick wall for 5 hours but it’s exhausting nonetheless.

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Zucker Hillside Hospital’s Clinical Psychologist, Dr. Curtis Reisinger, says people’s emotions are contagious. Producing mental and emotional responses to the things which happen in your office environment also takes physical exertion. If you hear sadness and complaints often enough, the feelings become shared group behaviour. As such, those vibes become part of you, and you often don’t even realise it is happening. The severity of mental exhaustion becomes even more apparent once you realise that the emotional state of your environment also drains you.

Mental fatigue stems from the brain’s dynamic decision- making and predicting activity. For example, when the colleague who always talks about her cats arrives, your brain is triggered: she is going to talk about Felix’s bowel movement, Ginger’s weird eating habit, and Kitsy’s newest rash, and you prepare your responses accordingly. Mental simulations such as “If she says x, I’ll say y” means your brain is functioning in the same way it would as if the physical interaction is already happening. Much like when Wayde van Niekerk practices: his muscles work as if he is running for Gold.

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While working, you’re doing the same predicting and preparing for possible scenarios, e.g. “if I do x, y should happen.” Your brain muscles are hard at work even when you’re creating a graph on MS Office you need to concentrate, navigate, and equate numbers, fonts, and alignment. And all of that is exhausting. Finally, Dr. Reisinger adds that those who do more anticipating than others, such as those with anxiety and/or depression, tend to experience this kind of physical exhaustion caused by mental fatigue more severely.

Dr. Feinsilver encourages office workers - or anyone who spends their days behind a computer - to treat mental fatigue as anyone would physical fatigue. Otherwise, you run the risk of weakening your immune system. After all, you can’t work if you’re dead from working.

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