A randomised control trial has found that office workers who use a standing desk alongside other interventions that encourage them to sit less and move around reduced their sitting time by an hour a day over one year.
The joint UK-Australian research team found that together, all of these measures led to small improvements in stress, wellbeing and energy levels at work.
As a forthcoming feature in IOSH Magazine’s September/October 2022 issue, published on 1 September, highlights, scientists have increasingly identified a clear link between sedentary lifestyles and raised levels of chronic disease. These include heart diseases, type 2 diabetes and some cancers. Sitting for prolonged periods has also been linked with higher rates in depression and anxiety.
A team of UK-based researchers and Australian collaborators found that although the improvements in stress, wellbeing and energy levels were not clinically meaningful, the research findings do highlight the health risks associated with too much time spent sitting.
The study, which has been published in the British Medical Journal (BMJ) today, looked specifically at office-based workers who have been identified as being one of the most sedentary groups in the working population, spending 73% of their working day and 66% of their waking day sitting down.
The research team evaluated the impact of a specially designed intervention known as SMART Work & Life (SWAL), which involved six councils in England taking part in a 12-month trial.
In total, 756 office workers drawn from two councils in Leicester, three in Greater Manchester and one in Liverpool were randomly assigned to either the control group or one of two intervention groups.
According to the BMJ findings, the average age of participants was 45 years of age. Women made up 72% of the study group and 75% were white British. Of those who took part, 85% worked as full-time council employees. The researchers noted that the average body mass index (BMI) at the start of the study was 26.5.
The control group continued to work as usual at a sit-down desk. The first intervention group also worked at a sit-down desk but was given resources to encourage them to move around. They were also informed about the health risks of spending too much time sitting in a sedentary position.
The second intervention group was also armed with this information but was provided with a height adjusted desk to encourage them to spend less time sitting down.
Employers for all of the participants were encouraged to introduce incremental changes around the office to encourage their employees to move around more. These included moving printers and waste paper bins and creating standing areas for meetings.
To measure how long participants were sitting down during the working day, the researchers provided an accelerometer device, which was worn on the thigh at the start of the study and then again 12 months later.
The researchers also recorded the participants’ daily physical activity levels. The participants self-reported their work, physical and mental health in a questionnaire.
The findings revealed that the participants in the second intervention group were three times more effective at reducing their time sitting down than the first intervention group.
After 12 months of monitoring the participants’ movements, the researchers found that individuals in the second intervention group had spent 64 minutes less per day on average sitting down than the control group. In contrast, the first intervention group had spent 22 minutes less per day on average sitting down than the control group.
Led by the University of Leicester, the research partnership also included University Hospitals of Leicester NHS Trust, the University of Salford, Loughborough University and the University of York in the UK, together with the University of Southern Queensland, the University of Queensland and the Baker Heart and Diabetes Institute in Australia.
Interestingly, the researchers noted that both intervention groups had demonstrated small, albeit non-clinically meaningful improvements in stress, wellbeing and energy levels at the three and 12 month stages. Participants that had been provided with a standing desk also reported lower pain in their hips, knees and ankles.
However, as the researchers note, although both intervention groups spent shorter periods of time sitting down than the control group, most participants replaced sitting with standing rather than moving around. Further work, they say, is needed to encourage office workers to be more physically active, particularly outside work.
The researchers also highlight a number of limitations in the study findings. For instance, because the participants understood the accelerometer’s purpose in measuring movement, it is possible this awareness did impact on their behaviour. They may also have been selective in their questionnaire responses.
Importantly though, the BMJ noted that, ‘this was a large, well-designed trial that mimicked a real world intervention, and results were similar after further sensitivity analyses, suggesting that they are robust.’
Dr Charlotte Edwardson, Associate Professor in Physical Activity, Sedentary Behaviour and Health at the University of Leicester, told IOSH Magazine: ‘Sitting down has become so ingrained in our daily activities. With the strategies we designed for this study we have shown that it is possible to change people’s sitting behaviour but this will be even more effective if supplemented with a height-adjustable workstation.’
In a linked editorial, Professor Cindy Gray, who works at the Institute of Health & Wellbeing Social Sciences at the University of Glasgow, said that the findings were ‘noteworthy’ because they had ‘come from a fully powered cluster randomised trial with objective measurement of sedentary behaviour at three and 12 months.’
She added that the move to home-based working after the COVID-19 lockdowns had probably increased workforce sedentariness. As a consequence: ‘understanding how to optimise occupational interventions to support people to sit less and move around their home during both work and non-working hours is essential.’
Jo Frape at IOSH said: ‘Sitting down for too long can do damage to our bodies but so can standing for prolonged periods. Many don’t realise that standing for too long puts a lot of pressure on the lower back and other muscles in the body, so workers on a production line or in a factory, who might be standing for eight hours or more, can be similarly at risk.
‘The key thing for employers to think about in this is job rotation and allowing their people to constantly vary their position. Employers need to do more to raise awareness of the importance of regular movement and to build this into their work culture because it’s fair to say that unless movement is part of their job, people won’t tend to move.
‘As well as ensuring all their risk assessments are in place, line managers will need to regularly monitor home workers to ensure they’re working safely and not working more than their hours, especially in positions that are damaging their posture and therefore opening the door to all those chronic health conditions linked to inactive work and lifestyles.’