RESEARCH REVIEW: Workout while you work...

With the bulk of many people’s sedentary hours being in the workplace, what does the research say about the efficacy of desk-bound physical activity? Review by Dr Mike Climstein PhD & Joe Walsh


KEY POINTS
  • Many people struggle to dedicate the recommended minimum 30 minutes each day to exercise
  • A large percentage of many people's waking hours are spent in sedentary office jobs
  • Researchers compared the metabolic costs (VO2, HR, energy expenditure) for study participants at rest; while seated and typing; while using a stationary foot cycle and typing, and while using a treadmill desk and typing
  • The study found that both the treadmill typing and cycle typing scenarios resulted in substantially higher energy expenditure than regular seated typing, with no detriment to typing capacity. 

Title: Energy expenditure while using workstation alternatives at self-selected intensities

Authors: Dr’s Schuna and colleagues. (College of Public Health and Human Sciences, Oregon State University, USA)

Source: Journal of Physical Activity and Health, 16, 141-148.

Introduction: It’s never ending, patients are referred to see us as they either have a number of risk factors predisposing them to chronic disease and/or conditions (i.e. high blood pressure, high cholesterol – including low high-density lipoproteins – and high blood sugar) or they have developed a chronic disease and/or condition and the general practitioner or specialist wants exercise or physical activity to be a component of the patient’s treatment regime. Simple – or so you’d think.

The majority of these patients have very busy lives: work and family (kids and often grandchildren as well), so a big part of clinical thinking on my feet is to find ‘potential exercise/physical activity’ time in their days. Often, this is no easy task! Now, if the average person sleeps 7.5 hours per night, that leaves potentially 16.5 hours, or as I like to think of it, almost 1,000 minutes to complete 30 minutes of exercise (minimum recommend daily amount by the American College of Sports Medicine). So technically, I’m asking for a mere 3% commitment of their awake time to complete exercise/physical activity – not a big ask by any means.

However, when you hear the patient describe their day, up at 6am, get the kids ready for school, then go off to work, then home to shuttle the kids to karate lessons, music lessons, gymnastics lessons, after school tutoring, all of which require a high degree of chauffer work (aka sedentary time). Then it’s home for dinner, school work with the kids, bath time, and suddenly that 30 minutes exercise time I’m requesting of them is looking like a big ask... But there is one time during most people’s weekdays when, if all else fails, the patients can complete exercise, and that is at work. This leads us to the topic of this Research Review, and I must declare that although I am an alumnus of Oregon State University, that had no influence whatsoever on selecting this article: good research is good research.

Dr Schuna and his colleagues initially discuss the increased risk of obesity, cardiovascular disease and cardiovascular-related mortality (i.e. deaths attributed to cardiovascular disease) associated with sedentary behaviour. Other chronic diseases attributed to sedentary behaviour includes type 2 diabetes and certain cancers. The authors then state that a substantial portion of the sedentary behaviour occurs in the workplace where most workers spend an average of 8 hours (or more) a day for 5 days each week. The focus, naturally enough therefore, turns to the concept of office-based exercise.

The researchers actually designed a very novel study in which they compared the metabolic costs (VO2, HR, energy expenditure) for study participants at rest (not that you’re actually resting while at work); while seated and typing; while using a stationary foot cycle and typing (a concept discussed in the Network Research Review, ‘Paid to exercise at work: does this make you a ‘professional exerciser?'); and while using a treadmill desk and typing. All participants were instructed to self-select their exercise intensity, and completed each of the four settings. Both the cycling and walking exercise was self-selected by the participant; however, they were required to keep typing while completing the exercise. Typing performance was assessed using typing performance software. All data was collected for 10 minutes at each station.

Results: A total of 16 volunteers (8 men and 8 women) with a mean age of 34 years participated in the study. The average pedal rate was just below 50rpms (ranged from 20 to 100rpms) while the cycling power output was low at an average of 18watts. The average treadmill walking speed was also low, at 2.1km/h, with no difference in walking speed between men and women. With regard to oxygen consumption, seated rest was the lowest averaging 3.6ml/kg/min (roughly 1 MET). The highest oxygen consumptions were seen, not surprisingly, with typing while exercising on the treadmill (approximately 10ml/kg/min): the typing while cycling was approximately 7% lower. With regard to heart rate, the lowest was seen at rest, approximately 65bpm, while the highest was seen with treadmill walking at approximately 79bpm (approximately 42% of the participants age-predicted maximal heart rate). Cycling while typing was slightly lower, with an average heart rate of 75bpm. Caloric expenditure was the highest, with typing while treadmill walking followed closely by typing while cycling at their desk.

With regard to typing performance, men typed the slowest while simultaneously treadmill walking and the fastest during pedal desk typing. Women had similar results, with their slowest typing rates during seated typing and treadmill walking and the fastest rates during pedal desk typing. With regard to accuracy, the highest was during seated typing for men and pedal desk typing for women.

The authors concluded that the self-selected exercise (treadmill and cycle) had substantially higher energy expenditures as compared to traditional office seated typing, and this ranged from a 1.8 to a 2.3-fold increase.

Pros: This is an interesting study. It is not surprising that typing while walking on a treadmill had the highest energy expenditure, however, if we consider the big picture, the findings indicate the potential of such behaviour to significantly impact caloric expenditure. For example, if a person were to use a treadmill desk for just 30 minutes per day each working day, they would burn 460kcals per week, which over a year would equate to over 22,000 kcals. If a kilo of fat equates to approximately 7,700kcals, then a person could potentially lose 2.8 kilos of fat a year (not that you can lose only fat). If you have a client or patient who is seriously interested in improved weight management, we believe this is a small investment that would be worthwhile, provided they complete the exercise on a regular basis.

Cons: None. We price checked and found a number of bike desks (i.e. bike is under the work desk, or a bike with a work desk mounted on it) available in Australia ranging in price from $30 to $600, although these devices are somewhat limited in terms of the intensity of exercise (i.e. watts). Treadmill desks that include the actual treadmill are understandably more expensive at up to $1,400). However, when you consider the accumulative effect of a small daily change in an individual’s energy expenditure at work over a yearly period, these devices can have a significant impact. Given the poor health outcomes associated with sedentary behaviour and sitting time, there is merit to a little extra work at work.

References