The obesity epidemic affects all high‐income countries as well as middle‐income and even low‐income countries.10
This has occurred because of a persistent positive energy balance that may be as little as 100 kcal/day.8
This energy imbalance reflects nutritional excess plus low levels of physical activity.7
Low levels of physical activity result from both low participation in formal exercise, such as going to the gym,11
and low levels of non‐exercise, habitual activity.12,13
The energy expended in association with non‐exercise activity, called non‐exercise activity thermogenesis (NEAT), is low in obesity specifically because walking activity is substantially less (>2 h/day less) in obese than in lean individuals.5
Because the majority of the waking week day is spent at work, it is not surprising that work is the predominant predictor of NEAT.14
Along with obesity, the sedentary nature of work is increasing15,16
because of the common use of desktop computers; by 2010 it is estimated that more than half of the workforce from developed countries will be working at computers.6
We are therefore interested in devising and validating approaches that promote physical activity in an obese person in the workplace without sacrificing work time. To this end, we devised a vertical workstation that can house the functionality and preserve the function of a standard office computer. We found that the use of the office vertical workstation was associated with substantial increases in energy expenditure in the obese volunteers we studied. Moreover, our volunteers enjoyed using the workstations. Were the vertical workstation to be used by an obese office worker to replace 2–3 h/day of sitting and if other components of energy balance were constant, a weight loss of >20 kg/year could occur.
The vertical workstation we describe is immediately available and therefore it is tenable that many desk‐based office workers could have access to such a device. Obesity is associated with decreased workforce participation17
and healthcare costs estimated in the US alone to be $100–200 billion/year.18
Hence, interventions such as the “walk‐while‐you‐work” desk might prove to be cost effective. Previous workplace strategies to promote physical activity have proven limited because either the activity component is too short in duration (eg, “climb the stairs” or “walk from the car park”) or the interventions require high levels of workforce commitment (eg, gym programmes).19,20,21
The “walk‐while‐you‐work” desk examines another approach that could overcome these limitations—namely, whether it is possible to change the mode of the office desk per se. We recognise that such approaches must embrace behavioural strategies to affect a sustained intervention22
and that this and other approaches can only succeed in increasing daily activity levels with the support of employers.
We acknowledge several limitations to this study. The studies were short in duration and did not extend throughout the workday. For example, it is conceivable that the self‐selected work‐and‐walk would only comprise 25% of the workday. Even so, this would represent an increase of 2 hours of walking per day, thereby closing the NEAT deficit in obesity.5
Second, there were relatively few subjects in this study and most were women; this is important especially if we are suggesting that the walk‐and‐work approach is widely applicable. Although we acknowledge this, we point out that our goal here was not only to test the feasibility of using the walk desk but also to define the energy expended in its use. A study with greater numbers would be unlikely to change our principal findings, although we recognise that further field‐testing and time‐and‐motion studies will be needed before broad‐based office application. Also, we did not assess work productivity; the ordering effect that was specific in our design prohibited us from doing so in this study. However, office‐wide trials will necessitate measures of productivity. Finally, although we showed surprisingly great excursions in energy expenditure, we did not show long‐term weight loss with the use of walk‐and‐work desks. Using the walk‐and‐work desk in weight loss studies is an immediate next step.
In conclusion, in this paper we describe the energy expenditure associated with using a walk‐and‐work desk that could allow seated, office‐based workers to be more active throughout their workday. The walk‐and‐work desk was associated with significant and substantial excursions in energy expenditure above sitting in obese subjects who previously took no exercise. Walking work was well tolerated by these obese individuals who used the computer in their normal fashion, and it is noteworthy that all our volunteers expressed enthusiasm to have access to “walk‐and‐work” stations after the study was complete. With population body weight, workplace sedentariness and healthcare costs projected to increase, interventions that allow people to work and yet be active could help reverse obesity.
What is already known on this topic
- Low levels of physical activity and NEAT are associated with obesity.
- When carefully assessed, people with obesity tend to be standing and walking for 2½ h/day less than their lean counterparts, which represents a potential deficit in NEAT of 350 kcal/day.
- NEAT is the energy expenditure associated with the routines of daily living and can be divided into work‐NEAT and leisure time‐NEAT.
- To examine approaches that could facilitate substantial increases in standing and walking time, we targeted work‐NEAT because many jobs in Europe and the US are conducted while seated.
What this study adds
- We invented a vertical workstation that incorporates a treadmill. This enables a previously seated computer‐based employee to work while walking.
- Individuals with obesity (n=15, BMI 30–35 kg/m2; 45 (SD) 19% body fat) were asked to test the vertical workstation for ease of use and energy efficiency.
- All subjects tolerated the workstation well and were able to use all the standard computer functions while walking and working. The mean (SD) sitting energy expenditure was 72 (10) kcal/h whereas the energy expenditure while walking and working at a self‐selected velocity of 1.1 (0.4) mph was 191 (29) kcal/h.
- The mean increase in energy expenditure for walking and working over sitting was 119 (25) kcal/h.
- If the vertical workstation was used for half the workday, increases in energy expenditure of 500 kcal/day could result.