We’ve all read that sitting for hours on end every day at a desk is really bad for us – but exactly how much is too much and are there ways to offset the damage?


Currently, as I write this article, I am sitting squarely on my seat – shoulders pushed back, spine straight and feet flat on the ground. My forearms are at a perfect right angle to my body as I type. When I look up at my screen, the cursor line is approximately 4 cm below eye level. I am the very picture of ergonomic harmony and balance. It’s really uncomfortable. I hate it.

I’d much rather be slumped against the back of the chair, more diagonal than perpendicular, or leaning heavily to one side, chin resting on my left hand while I web-surf with my right hand on the mouse. And that’s exactly what I did for many years – until I couldn’t anymore. Until I started to experience neck spasms and excruciating shoulder tension that just wouldn’t abate.

These days, I sit in a way that looks and feels unnatural, yet it has undeniably helped my neck and shoulder pain. So imagine how thrilled I was when my physiotherapist recently said to me: ‘Oh, and you must also make sure you stand up and move around every 15 minutes.’ Every 15 minutes… But he was adamant. ‘If you don’t prioritise physical movement, you could significantly reduce your lifespan.’

Of course I haven’t been living under a rock. I had heard that sitting for too long is supposed to be more dangerous to your health than playing a banjo on a tightrope, or smoking. But I had been working under the proviso that the odd break for a cup of tea, a loo visit, walking to and from the photocopier machine and standing up (sometimes) to pay the sandwich trolley lady were more than adequate. Surely?

A cursory internet search revealed a mixed bag. Headlines range from ‘Sitting too long can kill you’ (CNN) to ‘Why sitting down ISN’T killing you’ (Men’s Health). Time for an expert opinion.

Piet Nel, director of workplace wellness provider Ergonomicsdirect, admits this is ‘not an exact science’. All that’s really known is that being sedentary is really bad for you, but exactly how much sitting is difficult to determine because every person is different. According to Nel: ‘There are a number of variables that can have an effect, such as how long do you – on average – sit for every day? How ergonomically correct, or incorrect, is your chair and desk set-up? Do you take breaks and if so, how often? Do you have a medical history or condition such as chronic lower back pain that could be aggravated by sitting?’

Unfortunately, due to these variables, there isn’t a golden number when it comes to pronouncing how long one should or shouldn’t sit for. But there is evidence that suggests four hours of non-stop sitting is really bad for your body, and eight hours with only a few breaks is also harmful. Sitting for hours on end, while not great, probably won’t affect your health in the long term if it’s once-off, or now and then (think long-haul flights). It’s the daily repetition over a lifetime that creates the deadly cumulative effect.

‘There is extensive literature to show that sitting for long periods of time each day in the long term is associated with a multitude of detrimental health outcomes and all-cause mortality in men and women of all ages,’ says Lisa Micklesfield, associate professor from the University of Cape Town’s Research Unit for Exercise Science and Sports Medicine. ‘The group at particularly high risk are those who are very sedentary and also very physically inactive.’

When one considers that it is fairly common for the average office worker to sit at their desk all day and then go home and watch an hour or two (or three) of TV in the evening, this sitting business starts to paint a worrying picture – not just for life expectancy but also for quality of life in general. How fulfilled can you be when you spend the vast majority of your time in front of a screen?

The results of a meta-study by Louisiana State University and Harvard Medical School found that life expectancy drops by two years when people sit for more than three hours a day, and another 1.38 years for watching more than two hours of TV a day.

Okay, so committed sloths are in trouble, that hardly comes as a shock. What about folks who lead otherwise healthy lives? For example, they eat a balanced diet, don’t suffer from chronic stress and exercise regularly. But then they also happen to sit for most of the day?

‘It appears that the association between sedentary behaviour and these detrimental health outcomes is independent of physical activity and body mass index [BMI],’ says Micklesfield. ‘This means that even if you are physically active and have a healthy BMI, if you are very sedentary most of the time then you are at a higher risk of gaining weight and at increased risk for various cardio-metabolic outcomes, including type 2 diabetes, high cholesterol and increased waist circumference.’

There is a little wiggle room though. Micklesfield adds that a 2016 paper in the Lancet medical journal suggests that high levels of physical activity may offset the ‘dangers’ of sitting too much. So what are high levels? At least one hour of moderate physical activity every day (the WHO recommends a minimum of 150 minutes a week). The paper’s author, Ulf Ekelund from the Norwegian School of Sports Sciences and Cambridge University School of Clinical Medicine, says: ‘You don’t need to do sport or go to the gym. It’s okay doing some brisk walking, maybe in the morning, during lunchtime or after dinner in the evening. You can split it up over the day, but you need to do at least one hour.’

So, if you really can’t or don’t want to crowbar more mini movement breaks into your work day, then do no less than one hour of brisk walking daily.

Of course, while research and science give us useful information, let’s not forget that quaint old workhorse, common sense. ‘A good rule to follow is to listen to your body,’ says Nel. ‘Your body will generally tell you when you need to take a break or change your position. I would say, aim at four hours of sitting as a maximum during your working day.’

Are there any others steps you can take? ‘Definitely,’ says Nel. ‘The correct ergonomic positioning can make a significant difference to your comfort and reduce the likelihood of musculo-skeletal issues. Being in the correct position but still sitting for extended periods of time is still not ideal but it’s at least a step in the right direction.

‘Something as simple as using a laptop stand and an external keyboard and mouse with my laptop to improve the positioning of my shoulders, head and neck, reduced my neck pain and headaches by probably around 95%,’ he says.

Another solution is a standing desk. With the correct sit-stand workstations, you can change your position within a few seconds without influencing your work ‘rhythm’, says Nel. Companies can also look at designated ergonomic areas with standing desks where staff can choose to work.

Much of the solution is psychological. We need to change the way we think about work and our bodies. According to Nel: ‘Our dependence on computers and the 9 to 5 slog are going to be a part of our lives for some time to come. We should change the way we interact with our working environments. We should not adjust to our working environments. Our working environments should rather be flexible enough to adjust to our individual needs.’

By Rachel McGregor
Image: Gallo/GettyImages