Always feel exhausted at the end of the work day – even though all you’ve done is sit at a desk?
It turns out, mental concentration leads to changes in the brain that really can wear us out, researchers from Pitie-Salpetriere University in France have found.
When we carry out intense mental work over several hours, potentially toxic by-products can build up in the brain’s prefrontal cortex, according to the study. The result? That sense of mental fatigue sets in.
Ever felt irrational and cranky after hours of focusing on work tasks? Well, this could be why. The research found this process can alter our control over decisions, so we shift toward actions that require no effort or waiting. Essentially, the brain sort of starts to shut itself down.
“All this science simply means that thinking hard for sustained periods leads to mental exhaustion, and an interruption in executive functioning required to plan and make decisions,” says leadership and mental health expert, Ngozi Cadmus. “Fatigue thus becomes an inevitable consequence of using so much mind power.”
Not only is this mental exhaustion a bother in itself, these things can have a wider impact. As Cadmus notes: “Sustained exhaustion can lead to difficulties in a person’s daily life, impacting relationships and daily activities and inhibiting normal functioning.”
So, what can we do to help combat it?
Prioritise rest
In our productivity-obsessed world, making rest time a priority is vital. “If regular rest is not incorporated into a person’s daily structure, it can disrupt brain function,” says Cadmus. “Therefore, rest is essential to allow for the proper regulation of [the neurotransmitter] glutamate to its normal levels.”
Seek variety
Paula Allen, senior vice-president of research and total wellbeing at LifeWorks (lifeworks.com/en), says doing hours on end of the same tasks can exhaust our brains.
“The simple lack of variety in our daily routine is itself a mental strain, which many do not recognize. We need a balanced ‘diet’ for our brain, as much as we need one nutritionally,” explains Allen, who says we need “experiences that offer fun, accomplishment, connection with others, movement and changes of scenery. We feel unduly fatigued and more irritable when our range of mental stimulation is too narrow.
“When working from home, many employees also lose out on structural cues that are present in the office, such as meetings and scheduled lunch breaks. For some, this means breaks never happen. For others, it affects the ability to focus on a task in a time bound manner, as one hour blurs into the next.
“It’s important to listen to our bodies. If you’re finding a task you used to do seamlessly in the workplace now feel like a chore, then it’s time to take a break.”
Have a consistent night-time routine
For Cadmus, getting “a minimum of eight hours of sleep a night is important” for balancing mental exhaustion.
Allen agrees: “Sleep is major factor in both physical and mental wellbeing, and one that is currently at risk. Our Mental Health Index found 40% of Brits want to improve their sleep, demonstrating a need to address mental stress and provide information on general sleep hygiene as part of their wellbeing support and solutions.”
Take regular desk breaks
As well as your main rest time and lunch break, regular short breaks from your work station can make a big difference. Chances are you’ll be more efficient and productive overall.
“Step back, pay attention to your limits and communicate how you feel to your manager. Communication and problem-solving between employers and employees is key, and is becoming even more important as we navigate the post-pandemic working world,” Allen advises.
Cadmus also emphasises that “regular exercise” is beneficial for the brain and stress levels. So why not fit in a lunchtime run or workout, or step out for a short walk?
Stay hydrated
Dehydration makes us all feel groggier and more tired too, so ensure you drink enough water throughout the day. If mental fatigue is bothering you, consider reducing your caffeine and alcohol intake as well, says Cadmus. This will help mitigate the stress your brain is under.
