Nobody thought of office work as a life-threatening activity three decades ago. Back in 1981, we had not yet begun seriously fretting about the health effects of sitting at our desks all day, staring at blinking terminals and breathing recycled air. So it was dumb luck that a pile of data from that era existed to help a U.S.-Canadian team of researchers later prove the perilousness of our sedentary time.
Back in 1981, the Canada Fitness and Lifestyle Research Institute asked 17,013 adults how much of their day they spent sitting. Follow-up interviews conducted up to 13 years after the original survey were used to track the number of deaths and serious illnesses among the participants. When 21st-century researchers cross-referenced the death statistics with the sitting data, they encountered a stark result. Controlling for all other factors—age, existing illnesses and even physical exercise—the more a survey respondent sat in 1981, the more likely he or she was to be dead by 1994.
Sitting, it seemed, led to dying. “We were actually really surprised at how clear the relationship was,” says Peter Katzmarzyk, a professor at the Pennington Biomedical Research Center in Baton Rouge, La., and lead author of the 2009 paper published in Medicine & Science in Sports & Exercise.
Of the 3,000-odd participants who had said they “almost never” sat, less than 7% had died in the intervening 13 years. The number of survivors slid gradually downward as one looked across the table to the more sedentary groups. Of the 822 people who said they sat “almost all of the time,” nearly a fifth were dead. They were more than twice as likely to have died than the people who seldom sat.
“What we generally see,” says the Canadian-born Katzmarzyk, “is that people who sit more during the day have a higher risk of dying from any cause, and in particular, mortality from heart disease.”
Katzmarzyk’s survey was one of the first to definitely show the link between sitting and mortality, but researchers in Australia, Japan and across the developed world have come to similar conclusions.
As the emerging field of Inactivity Studies is learning, the more you sit, the more your health deteriorates. Doctors now speak of the risks of sitting and smoking in the same breath; no bigger threat to the welfare of office drones has animated water cooler discussions since sick building syndrome. Experts link too much sitting to rising rates of heart disease and obesity. A study of Australian women suggests people who sit for long stretches may be giving themselves colon and rectal cancer. And the moment we take a seat, we put ourselves at higher risk of Type 2 diabetes and halt natural processes that clear fat out of our muscle tissue. All of this just adds to a litany of office-related ills we are already familiar with through academic and anecdotal evidence, from stiff necks to carpal tunnel syndrome to eye strain. The printers in our offices spew particles that clog our lungs. Office clatter impairs our brain function. The offices themselves make us sick.
At the same time, we seem to be sitting at our desks more than ever. By the postwar period, people in advanced societies had long since shed the old, laborious ways to embrace a sedentary duo of desk work and television watching, hopping into private automobiles to shuttle between the two. Amid the rising affluence and convenience, science has ramped up efforts to quantify the negative side effects of a softer, seated way of life. We’d be wise to stand up and take notice of the results.
In 2003–04, researchers from Vanderbilt University strapped plastic devices called Actigraphs to the legs of 6,329 Americans ages six and up to measure how much of their waking hours they spent sitting, reclining or lying down. It turned out participants spent 55% of the time, or 7.7 waking hours off of their feet. Studies relying on self-reported data have come to even more alarming conclusions; a survey conducted by the U.K. branch of Weight Watchers, for example, found that people were sitting an average of 14 hours and 39 minutes a day.
The danger of sitting lies in how it quiets various physical processes. Depending on body weight, a seated person will burn up to 50 fewer calories an hour versus standing. Prolonged sitting has been shown to increase the risk of Type 2 diabetes. In 2005, U.S. scientists Theodore Zderic and Marc Hamilton discovered that sitting reduced by 90% the activity of lipoprotein lipase, an enzyme that sweeps fat out of skeletal muscle. The consequences of that discovery are not yet fully understood, but it is enough for some experts to finger the humble desk chair as a major suspect in the dramatic fattening of the industrialized world in recent decades.
People may blame 800-calorie burgers and a lack of exercise for the western world’s obesity epidemic, but there is evidence it is our jobs, not our off-hours habits, that have changed. Studies show people in industrialized countries actually exercise more than in decades past. Meanwhile, reports of our obscene overeating may be grossly overstated.
“Are we eating more?” asks Timothy Church, who believes we indeed may not be. A professor at Louisiana’s Pennington research centre, he was lead author of a paper, published in May in the journal PLoS One, that argues the fattening of the working population may be almost entirely caused by becoming less active at work. “Personally I think we’re wired to eat a lot. I’m not totally convinced that we’re eating that much more than we have in the past. I could be wrong, but there’s no data to prove me wrong.”
What the data can prove, however, is that U.S. workers are expending substantially fewer calories at work than they used to. Church and his team attempted to solve the obesity puzzle by mining U.S. federal job data going back to the early 1960s. Using previously published systems for estimating the physical intensity of different jobs, they calculated the number of calories burned by the American workforce in different eras. Overall, Americans were becoming less active during the workday. The number of men employed in relatively sedentary service-related positions has risen, while jobs in manufacturing and agriculture have vanished. The percentage of jobs requiring “moderate” physical activity, as opposed to “light” or “sedentary,” dropped to 20% in 2008 from 48% in 1960. If the estimates were correct, men were burning about 140 fewer calories per workday in 2003–06 than in 1960–62. Women were expending 124 fewer.
Next, the team wanted to know what effect that difference would have on people’s weight. A mathematician concluded that over the five decades, male U.S. workers in their forties should have bulked up from 76.9 kilograms on average to 89.7, just through the changes in their work situations. Her estimate was very close to the weight, 91.8 kilograms, that the men in that category had actually reached. (It is worth taking a moment to properly digest the figures: the average modern employed 40-something American male weighed fully 32 pounds more than in the early 1960s.)
Of course, some workers are still plenty active—and appear to be healthier for it. The earliest sign of the dangers of sitting arrived in 1953, in a famous British study published in The Lancet. Searching for reasons behind an observed increase in the incidence of heart disease, medical researchers sifted through the health records of 31,000 men who worked for the London Transport Executive as drivers and conductors. A pattern emerged when the researchers divided the men between drivers, who tended to sit, and conductors, who tended to stand and walk. While the conductors suffered from angina more often than the drivers, they were better off overall. The conductors weren’t as susceptible to more serious forms of heart disease. When they did suffer from coronary artery disease, it hit them at a later age and they had a better chance of surviving it. Altogether, conductors enjoyed a “substantially lower” mortality rate than drivers.
In a follow-up study, researchers noted uniform sizes and observed that drivers were more prone to sudden death by heart attack than conductors—regardless of physique. Worry not for the fat conductor. Save your prayers for the skinny driver.
Other studies found the same pattern in groups ranging from San Francisco dock workers to British civil servants to Harvard graduates: sit more, die younger.
While a link between idleness and poor heart health has been established for nearly six decades, the paradigm that emerged said long periods of sedentary behaviour ought to be all right as long as it was offset by enough physical activity.
Leaving aside the fact that a relatively anemic 15% of Canadians are physically active enough to satisfy even modest government recommendations—Health Canada suggests 150 minutes per week of moderate-to-vigorous physical activity—the evidence is mounting that you cannot offset the deleterious effects of sitting simply by exercising more. A vigorous hour here and there may not be enough to erase the harm of too much time on one’s derrière.
“We have shown even in people who are meeting the physical activity guidelines, sitting is a bad thing,” Katzmarzyk says. “Just because you’re meeting the physical activity guidelines, you should not ignore what goes on the rest of the day.”
To ignore this advice and plunk ourselves down longer and more often than the human body was designed for is to tempt both a host of unpleasant health effects and early death.
But office work isn’t just making us more prone to illness and disease. It wears on the body in all sorts of other ways, both obvious and obscure. “Unless you’re counterbalancing sitting all day with some healthy activity, it’s almost inevitable that something will come up after years of sitting at a desk,” says Brenda McGibbon Lammi, an Ottawa-based occupational therapist. It’s not just the sitting: she stresses that there are other ways offices can be worse for our health than we may realize. “They can be very bad, to sum it up,” she says.
What occupational therapists refer to as “musculoskeletal” problems are rampant in office dwellers. The U.S. National Institute for Occupational Safety and Health has found that 75% of workers who use a video display terminal experience at least “occasional” discomfort of the neck, back and shoulders; 20% to 25% experience it almost daily. In 2008, a Thai research team surveyed 2,000 office workers in 54 Bangkok workplaces and found that fully 63% of them with at least one year of experience on the job were experiencing some kind of musculoskeletal pain. The study also revealed that women are more likely to suffer from these ailments than men.
Studies have estimated 3% of the U.S. population suffer from the pain and numbness of carpal tunnel syndrome (although the jury is still out as to whether its causes are genetic, occupational or a combination of the two).
Carrie Dyck, a linguistics professor at Memorial University in St. John’s, Nfld., was one of the countless affected by pain she believes came from sitting down all day. “My legs felt bad,” she says. “Think ‘deep vein thrombosis.’ Also, turning my torso while sitting often meant risking a lower back injury. The worst thing, though, was that when sitting, it seemed all too easy to ignore any physical discomfort and work for too long a time.”
Your eyes suffer their own daily assault. McGibbon Lammi says they can be harmed by video monitors and cheap fluorescent lighting that flickers all day, often imperceptibly. “That has the effect of sitting under a strobe light all day long. You can’t recognize it, but your body does. That in itself can cause headaches and eye strain, and people don’t recognize why, or the source,” she says.
Eye strain, while a minor problem for most, can be associated with worse for others—look up “central serous retinopathy,” a disease that involves fluid leaking into the eye and that causes blurred vision and even temporary blindness.
As our desks cripple our limbs and our computers attack our eyes, our printers may be assaulting our lungs. Queensland University of Technology professor Lidia Morawska argued in 2007 that many common computer printer models cough up minuscule particles that, in her words, can be as dangerous as cigarette smoke. Depending on the composition of the ultrafine particles emitted during a short printing job, a worker might be exposed to a risk of cancer or illnesses of a respiratory or cardiovascular nature. Her report concluded that 17 of 62 printer models studied were dangerous “high particle emitters,” although manufacturers disputed the results.
On a fundamental level, even the fact that offices tend to trap us indoors could be killing us. In 2008, an Australian study showed that even in the sunny city of Brisbane, as many as 42% of the population had deficient or inadequate levels of vitamin D. The problem was especially pronounced in office workers, the authors noted. Medical researchers have keenly studied the relationship between vitamin D and cancer in recent years, with evidence mounting that a lack of sunlight can contribute to tumours of the breast, prostate and colon.
Even workspaces that may “look” healthy and modern to workers may hamper their well-being. Employers like open-plan offices because they can save on costs. Employees appreciate the chatty environment, according to a 2001 Cornell University study. Open offices, it said, “significantly benefit communication that speeds the overall work process while contributing to high-quality work and employee satisfaction with their job.”
But would that argument stand up to rigorous scrutiny? A research project connected to the British television show The Secret Life of Buildings attached brain-wave measuring devices to people’s heads and found that the low-level racket endemic to open workplaces interrupts one’s concentration. “If you are just getting into some work and a phone goes off in the background, it ruins what you are concentrating on. Even though you are not aware at the time, the brain responds to distractions,” a neuroscientist interviewed by the program told The Daily Telegraph.
More seriously, an Australian team reviewing the literature on open-plan offices—while confirming the British program’s findings about productivity—found more “shocking” effects on health and well-being, such as higher airborne disease transmission in workplaces without walls. In the Asia-Pacific Journal of Health Management, Queensland University of Technology researcher Vinesh Oommen wrote: “Employees face a multitude of problems such as the loss of privacy, loss of identity, low work productivity, various health issues, overstimulation and low job satisfaction when working in an open-plan work environment.”
If the evidence solidifies that sit-down jobs at typical offices are responsible for shortening and lowering the quality of our lives, workers will inevitably stand up to their employers and ask for solutions. A revolution in workplace design could be expensive, but so are the various ailments increasingly associated with desk work.
Some companies are making changes now rather than wait for academics to shore up the argument. Ergonomists at Steelcase, the world’s largest maker and supplier of office furniture, say some employers are already shifting to a more mobile workplace to address the too-much-sitting issue. Sales of alternative, standing desks are growing, albeit slowly. In addition to desks that offer sitting and standing options in a single unit, the company makes the Walkstation, a combination desk-treadmill with a maximum belt speed of two miles per hour (it sells for US$4,399). Research In Motion and Chevron Canada are among the major employers that have begun investing in alternative desks. There is some evidence that office workers will embrace the new gear. “Don’t even think of taking [the tables] away from them. Once the employees feel the benefit, the change of posture through the day, [sitting] is not an option anymore,” says Dave Trippany, a senior researcher and corporate ergonomist for Steelcase, who works out of its R&D centre in Grand Rapids, Mich.
“They love having that freedom of choice, to stand every day.”
Dyck, the Memorial University professor, bought a standing desk through her department’s office budget five years ago and never looked back. She still sits down to do any careful reading but uses a purpose-built standing desk for computer work. It took about “30 seconds to get used to it,” she recalls. But adopting a standing desk was not a cure-all. “I feel not much better. [But] it’s not worse, for sure. It didn’t really help my back at all,” Dyck says.
Dyck’s colleagues have inspected her arrangement with interest, but no one has copied it. Standing at a desk frankly looks goofy to some people, probably because we associate sitting with working. Steelcase’s ergonomists say peer pressure is among the biggest obstacles to alternative office furniture. Galen Cranz, a sociologist and professor of architecture at the University of California Berkeley who has long crusaded for more active work environments writes via e-mail: “It will take cultural change in order to make significant change.”
Change could bring problems of its own. Employers will note the advice of the Canadian Centre for Occupational Health and Safety, which warns that standing all day can cause sore feet, swelling of the legs, varicose veins and lower back pain.
Meanwhile, if there is a limit to the time a human being should spend sitting in a day, no one seems to know what that is. Katzmarzyk counsels a common-sense approach. “We don’t have specific guidelines—exactly how much you should sit or whatever. It’s more like we do know that people who sit more have more health problems, so you should definitely sit less. It’s like sun exposure,” he says.
The good news is the solution—namely, moderation—may be almost as simple as the problem. Taking frequent standing and walking breaks seems to lift the evil spell of sitting to an extent.
Doctors at the Mayo Clinic have developed a concept called NEAT (for non-exercise activity thermogenesis), which involves measuring energy expenditure during everyday activities. “NEAT includes all those activities that render us vibrant, unique and independent beings, such as going to work, playing guitar, toe-tapping and dancing,” the researchers recently explained. NEAT proponents advocate building more physical activity into a typical day, offering suggestions such as walk-and-talk meetings and workplace yoga sessions to kick off the morning. Even fidgeting and chewing gum offer a slight metabolic boost.
But what the NEAT researchers are ultimately arguing for is much bigger, nothing short of redesigning the workplace with the needs of the human body at its centre. “It might be viewed as far-fetched and expensive.…However, technological capability exists that makes this immediately possible,” researchers argued in a 2006 paper in a journal of the American Heart Association.
To keep things in perspective, desk work remains less dangerous than, say, construction or mining. The office pessimist will note that everything we do after getting out of bed puts us in some kind of risk of injury, however small. And human nature predicts we will always find new reasons to rue our jobs. Whatever we might do in the future to make our working days more wholesome, be it mandatory sunshine breaks or a treadmill in every cubicle, there will probably never be a cure for work itself.