Most people would probably benefit from increasing their physical activity. One way to achieve this might be reducing the amount of time we spend sitting down at work. In January 2015, a new Cochrane Review examined the evidence on interventions that might help and this was updated with several new studies in March 2016. We asked one of the authors, Jos Verbeek from the Finnish Institute of Occupational Health to tell us about the need for the review and its latest findings.
John: Most people would probably benefit from increasing their physical activity. One way to achieve this might be reducing the amount of time we spend sitting down at work. In January 2015, a new Cochrane Review examined the evidence on interventions that might help and this was updated with several new studies in March 2016. We asked one of the authors, Jos Verbeek from the Finnish Institute of Occupational Health to tell us about the need for the review and its latest findings.
Jos: Most jobs today are sedentary, requiring people to sit for long periods of time, and they tend to do so despite the growing interest in being more active. This is getting worse as advances in technology and pressure from colleagues mean that many people do not leave their desk, even for communicating with others who might only be an office away. Although doing the recommended levels of physical activity of 150 minutes of moderate-intensity aerobic exercise each week and resistance exercises twice a week can help, this is not enough and we need to find effective ways for people to become more active at work.
Our review looks at how to make it easier for people to sit less at work but, when we think of an average office, we can see how reducing sitting is a huge challenge. It might need changes to the architecture, new furniture, or changes in the office routine. This can be expensive and disruptive, which makes it even more important to know whether interventions that aim to reduce sitting, such as desks that allow you stand while working, actually do reduce sitting. Our review shows that there is some evidence that some of these, at least, might help.
For this update, we have agreed on 20 eligible studies, more than doubling the size of the original review. The studies were done in a variety of settings: a research institution, an academic institution, a government agency, a police organisation and private organisations; making the population largely representative of office workers. Unfortunately, though, all the studies were at high risk of bias and it’s difficult to interpret the findings because of limitations in their study designs and quality, and inconsistent results.
Seven studies investigated the introduction of sit-stand desks, which are height adjustable so that people can work at their desk while either standing or sitting. These sit-stand desks, with or without information and counselling, reduced sitting time by between half an hour and 2 hours in an 8 hour workday.
Desks in which people can walk on a treadmill as they work, reduced sitting time at work by about 30 minutes a day, but there was no effect of cycling workstations on inactive sitting time at work. Counselling also reduced sitting time at work by about 30 minutes a day in two studies.
On the other hand, the two studies of computer prompts, in which the computer user is reminded and encouraged to move from their sitting position had mixed results. One showed that the prompts reduced sitting by just under one hour per day, while the other did not find a reduction in sitting time. Two studies of policy changes in the worksite that were intended to introduce walking strategies, such as walking during breaks, also failed to show any considerable decrease in sitting and a study of mindfulness training found no effect on sitting at work.
In summary, this latest version of our Cochrane Review shows that sit-stand desks can reduce sitting at work, but the quality of evidence is very low. We still cannot be sure if standing at work can reverse the harmful effects of sitting. The effects of the other interventions are even less clear and there is a need for high quality research into the effects of the different types of interventions. Thankfully, many trials are underway at the moment and the results of these might change our conclusions.
John: Whether you are standing or sitting now, if you would like to learn more about the interventions that were assessed in the review and its results, go to Cochrane Library dot com and find the review and its future updates with a simple search for the word 'sitting at work'.