Do sit-stand workstations improve cardiovascular health?

Author: David Rempel

Printable version: Do sit-stand workstations improve cardiovascular health? (PDF)

Sit-stand workstations have been around for many years but they have recently gained in popularity. The reasons are many but reduced cost, increased marketing, and a promise of improved health seem to be the primary drivers.

While there is some evidence that the use of sit-stand workstations will relieve low back pain and improve productivity (Garett 2016)1, there is little evidence that more standing at work will improve cardiovascular health. Cardiovascular health is defined here as myocardial infarctions and coronary artery disease. None-the-less, several countries and professional organizations have published public health guidelines recommending more standing for sedentary work (Straker 2016, AMA 2013)2,3.

The basis for pushing more standing to improve the cardiovascular health of office workers follows from a misinterpretation of epidemiologic and physiologic studies.

First, the epidemiologic evidence. At least 5 large, prospective studies have found that increased total sitting time, i.e., combining work and leisure sitting time, increases the risk of cardiovascular disease (VanDerPloeg 2012, Borodulin 2014, Petersen 2014, Matthews 2015, Chao 2015)4,5,6,7,8.  These studies controlled for important confounders such as age, education, smoking, employment, leisure time physical activity, BMI, diet, hypertension, and cholesterol.  The risk increased approximately 50% when comparing those who sat more than 10-12 hours per day to those who sat less.

On the other hand, at least 6 large, prospective studies have found that increased occupational sitting time did not increase the risk of cardiovascular disease (Krause 2000, Stamatakis 2013, Chao 2015, Kikuchi 2015, Moller 2016, Smith 2017)9,10,8,11,12,13.  Again the studies controlled for important confounders.  Two of the studies found the inverse. Workers who predominantly sat at work had greater protection from cardiovascular disease than those who predominantly stood (Krause 2000, Smith 2017) 9,13.

Why the differences? By and large, these were all well-designed studies of good quality with good control of confounders.  The differences are likely to be explained by the sitting at home time, the couch potato time, rather than the sitting time at work.

This brings up the second level of evidence, the effects of sitting vs. standing on overall metabolism, blood pressure, and lipid and glucose metabolism. Surprisingly, overall metabolism is almost the same for sitting and standing. The differences are small and range from 0 to 30 kcal/h (Tudor-Locke 2014)14. Furthermore, when you consider that, on average, someone with a sit-stand workstation, and some system to remind them to stand, will stand for an extra 1-2 hours more per day, at best, a sit-stand workstation would lead to 60 kcal extra metabolism per day, or half a bottle of beer.

Fidgeting can increase metabolism by 50 kcal/h, but a real increase in metabolism requires pedaling or treadmill walking at work (increase of 100 to 200 kcal/h) (Tudor-Locke 2014)14 and these interventions at work are noisy and not well-accepted.

A large Danish study found that leisure time sitting was associated with increased triglycerides, cholesterol, weight, and waist circumference; however, occupational time sitting was not associated with any of these markers (Saidj 2013)15. This supports the couch potato theory of sitting and cardiovascular risk – there is a difference between sitting at work and lounging in front of a TV.  Several small intervention studies have demonstrated mixed effects of sit-stand workstations on blood pressure but they suffer from serious methodologic limitations (Mainsbridge 2014; Graves 2015)16,17.

Conclusion

In summary, there is no evidence supporting the theory that increased occupational sitting time increases cardiovascular risk. In fact, the opposite may be true - there is some evidence linking increased occupational standing time to cardiovascular risk. As health and safety professionals it is important that we do not promote health based interventions, especially for cardiovascular disease, for which there is a lack of good evidence.

Key messages

  • Some evidence that the use of sit-stand workstations will relieve low back pain and improve productivity
  • Little evidence that more standing among office workers will improve cardiovascular health
  • The effects of sitting vs. standing on overall metabolism, blood pressure, and lipid and glucose metabolism is almost the same for sitting and standing - a real increase in metabolism requires pedaling or treadmill walking at work (increase of 100 to 200 kcal/h) (Zderic 2006, Tudor-Locke 2014)

Implications for the prevention of MSD

  • There is some evidence that the use of sit-stand workstations will relieve low back pain and improve productivity. However, there is no evidence supporting the theory that increased occupational sitting time increases cardiovascular risk.

References

  1. Garett G, Benden M, Mehta R et al. Call center productivity over 6 months following a standing desk intervention. IIE Transactions on Occupational Ergonomics and Human Factors 2016; 4:188-195.  
  2. Straker, L, Coenen, P, Dunstan, D, Gilson, N, and Healy, G, Sedentary work – evidence on an emergent work health and safety issue, Safe Work Australia, Canberra, Australia, 2016, pp 79.
  3. AMA. Health risks of sitting. 2013; US. p. 460.
  4. van der Ploeg et al. Sitting time and all-cause mortality risk in 222,497 Australian adults. Arch Intern Med 2012; 172:494-500.
  5. Borodulin et al. Daily sedentary time and risk of cardiovascular disease: the National FINRISK 2002 Study. J Phys Act Health 2014; 12(7):904-8.
  6. Petersen CB et al. Total sitting time and risk of myocardial infarction, coronary heart disease and all-cause mortality in a prospective cohort of …Int J Behav Nutr Phys Act 2014; 11:13.
  7. Matthews CE et al. Mortality benefits for replacing sitting time with different physical activities.  Med Sci Sports Exercise 2015; 47(9):1833-40.
  8. Chao JY et al. Cross-sectional associations of total sitting and leisure screen time with cardiometabolic risk in adults, Results from the HUNT Study.  J Sci Med Sport 2015; 17:78-84.
  9. Krause et al. Standing at work and progression of carotid atherosclerosis. SJWEH 2000; 26(3):227-236.
  10. Stamatakis E et al. Are sitting occupations associated with increased all-cause, cancer, and cardiovascular disease mortality risk? A pooled analysis….  PLOS One 2013; 8(9):e73753.
  11. Kikuchi et al. Occupational sitting time and risk of all-cause mortality among Japanese workers. SJWEH 2015; 41(6):519-528.
  12. Moller SV et al. Multi-wave cohort study of sedentary work and risk of ischemic heart disease. SJWEH 2016; 42(1):43-51.
  13. Smith P et al. The relationship between occupational standing and sitting and incident heart disease over a 12-year period in Ontario, Canada.  Am J Epi 2017; 187:27-33.
  14. Tudor-Locke C et al. Changing the way we work: elevating energy expenditure with workstation alternatives. Int J Obesity 2014; 38:755-765.
  15. Saidj M et al. Separate and joint associations of occupational and leisure-time sitting with cardio-metabolic risk factors. PLOS One 2013; 8(8):e70213.
  16. Mainsbridge CP et al. The effect of an e-Health intervention designed to reduce prolonged occupational siting on mean arterial pressure. JOEM 2014; 56(11):1189-1194.
  17. Graves LEF et al. Evaluation of sit-stand workstations in an office setting: a randomized controlled trial. BMC Pub Health 2015; 15:1145.


Last updated: 2018

Disclaimer: Position papers are funded by the Centre of Research Expertise for the Prevention of Musculoskeletal Disorders, which receives funding through a grant provided by the Ontario Ministry of Labour. The views expressed are those of the authors and do not necessarily reflect those of the Centre nor of the Province.