Be upstanding, Doctor. It will do you good

MANY occupations can involve high levels of sitting as well as periods of prolonged sitting. Such patterns have been shown to be associated with poor health outcomes, and this has stimulated research and practice centred on ways of reducing such sedentary behaviour.

GPs are likely to spend a considerable amount of their day sitting, and thus may wish to change their own behaviour. Moreover, they could also encourage less sedentary lifestyles in their patients. A recent survey of GPs in the UK showed that 61% would like a sit–stand desk in their consultation room, while 19% already had one. Interestingly, most GPs thought sit–stand desks could be used for telephone consultations and administration tasks.

In a large study recently published in the BMJ, British and Australian researchers – including us – did a randomised controlled trial of ambulatory desk-based office workers with the primary aim of reducing daily sitting time. This was called the Smart Work and Life (SWAL) study. Set in local government council offices across three areas of England, the study provided a range of strategies to reduce sitting time across the day. Specifically, two experimental groups were created with one having a height-adjustable sit-to-stand desk provided (SWAL + desk) and one not (SWAL). In addition, both groups had a range of behaviour change strategies designed to reduce sitting and increase standing and moving that were facilitated by a workplace champion. Included were organisational strategies (eg, support of senior leaders and recruitment of workplace champions), environmental strategies (eg, relocation of printers, standing meetings), and individual and group strategies (eg, online education, free smartphone applications). The intervention groups were compared with each other and with a control group at 3 and 12 months, with approximately 250 people in each group. Sitting time was assessed using a research-grade device worn by participants, and a number of health, lifestyle, and work-related assessments were made primarily using surveys.

At 12 months, the SWAL and SWAL + desk groups sat for 22 min/day and 64 min/day less than controls respectively, and this effect was consistent across age and body mass index. Favourable changes in prolonged sitting were also observed for the intervention groups. Reductions in sitting were largely replaced with extra time spent standing rather than moving, and such changes were seen at work rather than at home or in leisure time. Small improvements were noted for stress, vigour and wellbeing, and pain in the lower extremity, although such changes were small and may not be clinically meaningful. No changes were noted in other health, work or wellbeing outcomes.

So just how relevant are these changes seen in sitting time as a result of these interventions?

Remarkably, the magnitude of change observed for the SWAL + desk intervention is identical to what has been reported in a recent meta-analysis of multiple sedentary behaviour reduction intervention studies in adults, demonstrating high feasibility for behaviour change. For clinical perspective, a meta-analysis published in the BMJ in 2019 showed that approximately 70 min/day more sitting relative to those who average 7.5 hours per day increases mortality risk by at least 28%. Although our study did not include mortality as an outcome, on the basis of these findings the 64 min/day reduction observed in the SWAL study would be expected to derive substantial mortality risk reduction. Similarly, replacing 30 minutes of sedentary time with activity has been associated with lower mortality risk, particularly among those who do little physical activity. With evidence showing that Australian adults sit for an average of 8.8 hours per day, these findings are likely to have high relevance for a large segment of the Australian population. For office workers, the provision of a sit–stand desk may be particularly impactful, since up to 75% of the workday can be spent sitting at the work desk.

It is now been 8 years since our letter published in the MJA put forward, to our knowledge, the first ever call-to-action for employers and doctors to recognise and respond to the health hazards of too much sedentary time. There is now strong evidence showing that exposure to high volumes of sitting significantly increases the risk of all-cause and cardiovascular death and the incidence of cardiovascular disease, type 2 diabetes, and some cancers.

The SWAL findings further confirm that alterations to the individual physical environment (eg, sit-stand desks) can achieve substantial reductions in sitting time and that in the absence of such alterations, contemporary offices may still be failing to provide a safe system of work. This has likely to have been further exacerbated by the COVID-19 pandemic and the resulting mitigation strategies, including the greater proportion of workers now working from home, whereby significant increases in sedentary time have been consistently reported.

As noted above, and consistent with previous research, the sit–stand desk was a key driver of the behaviour changes achieved through the SWAL intervention. Sit–stand desks enable users to regularly change posture between sitting and standing while continuing to undertake desk-based work. In addition to facilitating regular postural shifts, they can also enable users to adjust their desk to the correct ergonomic position for either a seated or standing posture.

However, as highlighted in a survey of furniture purchasing decision makers, just installing desks is unlikely to be sufficient to achieve optimum usage. Our sitting behaviour is influenced by multiple factors, including how we feel, social norms, policies and the environment. Sitting is also incredibly habitual. We typically do it without thinking, so it can require a conscious effort to get up regularly. The SWAL intervention targeted these other influences, particularly at the workplace, and used workplace champions to help promote and embed the changes into the workplace culture. In Australia, we have used a similar model with our BeUpstanding program, which uses a train-the-champion approach to help create a dynamic workplace culture where sitting less and moving more is the new norm. Importantly, with the massive disruption to how and where we work resulting from the COVID-19 pandemic, we have been able to extend this dynamic cultural shift to support workers to sit less and move more, no matter where they are working.

Although it is fantastic if a whole organisation can support their desk workers to be more active through programs like SWAL and BeUpstanding, there are still steps an individual can take straight away if they are looking to reduce their prolonged sitting. If you or your patients have a sit–stand desk, or are thinking of purchasing one, here are some quick tips to help enhance their use:

• mix it up, aim to get up and down at least every 30 minutes, neither sitting nor standing for too long at a time;
• leave the desk in an upright position whenever you walk away from it, particularly at the end of the day;
• set a timer; sitting is very habitual, so it is easy to forget to mix it up. Using a timer can be a great prompt until postural shifts become habitual.

Professor David Dunstan is from the Baker Heart and Diabetes Institute and Deakin University.

Professor Stuart Biddle is from the University of Southern Queensland.

Professor Genevieve Healy is from the University of Queensland.

The statements or opinions expressed in this article reflect the views of the authors and do not necessarily represent the official policy of the AMA, the MJA or InSight+ unless so stated.

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