A hard day’s night

Why longer working hours come with a long list of risks

Long working hours — specifically those in excess of 50 hours per week — may seem designed for productivity gains but, in practice, they produce just the opposite effect. 

Working more than 50 hours per week comes with a sharp decline in productivity, according to research out of Stanford University in California.

And employees who work 55 to 70 hours per week are producing almost nothing during those additional hours, suggests the study The Productivity of Working Hours by John Pencavel. 

Yet long working hours aren’t really on the radar for many employers and HR departments, despite the fact that in many workplaces, they should be a pressing concern, said Pencavel, a professor at Stanford.

“The fraction of men in the United States… working more than 48 hours per week has increased over the last few decades. So long working hours is not a relic — it has not only happened 100 years ago, it happens for some workers today,” he said.

And the productivity argument is just one piece of the equation, said Pencavel — but it helps build a business case employers can’t ignore. 

For employees working fewer than 49 hours per week, variations in productivity and output were proportional to variations in working hours, found the study. But after 50 hours in a week, productivity began to decline as working hours increased  — ceasing altogether at about the 63-hour mark.

The science of productivity 
No matter what we’re working on, human performance deteriorates when we’re at a task for a long time — it’s just the reality of fatigue, said Cameron Mustard, president of the Institute for Work and Health in Toronto.

“For those of us who are working Monday to Friday, eight hours (a day), fatigue seems to come into play at about eight hours or so,” he said. 

“The cognitive psychology of human performance has documented this pretty clearly.”

And it’s not just about the baseline number of hours worked every week — the distribution of those hours is also a significant factor in productivity, said Pencavel. 

“For example, some workers (in the study) were working seven days a week so; in other words, they didn’t have a day of rest. So in those weeks, output was really harmed,” he said. 

“It’s not only the length of the working week but also it’s just the distribution over the week. So, in other words, workers need time for repair.”

The idea that more hours equals more accomplished is an illusion, said Lois Kennedy, productivity expert and president at project management consultants 3 Step Results in Toronto. 

“We’re under the illusion that the more hours we put in, the better, and if we multi-task, we’re getting more done. Both of those things are an illusion. You’re actually doing less — you’re being less productive in working over 50 hours than working under,” she said.

“It’s because you don’t work to your potential. You get distracted, it’s very hard to stay focused. You get tired and if you get tired, you get sick because stress sets in, and stress is awful with regards to our health.”

Risks to employer
There’s a whole laundry list of risks to both employers and employees when working hours are excessive, said Pencavel. Greater risk of workplace accidents or injuries is one of the more obvious ones.

“Other work has shown that accidents increase during overtime work — accidents, injuries, production of defective products… output is just one dimension of the costs of long working hours,” he said.

That could very well mean higher disability costs, benefit costs and insurance claims for employers, along with the need to replace injured employees or employees on stress leave, said Kennedy.

“What employers don’t understand is they ask less employees to do more and more and more, but what they’re actually doing is overwhelming their employees to the point that stress sets in and then they get sick. And then they’re paying for people to be off (on leave),” she said. 

“If they burn out, then they’re back to square one training new employees.”

The risk of injury goes up the longer people work consecutively as fatigue increases, said Mustard — which is why there are legislative restrictions on hours of work. 

“Working long hours increases the risk of error,” he said. “There are some occupations where it’s been recognized that from a public safety perspective, there should be even more specific definitions of the allowable duration of work.”

Some examples include long-distance truck drivers, commercial airline crews, doctors and nurses — all occupations that could pose health risks not just to the workers but to the public if work hours are excessive. 

Even if public safety is not at risk, there are real risks to an organization if fatigued employees start to make errors, said Kennedy.
“You can only work so long at your highest peak potential and then you get tired — and you make mistakes… that’s when people start cutting corners because they just want to get it done. It is a risk (for the company),” she said. 

“So it’s a vicious circle, this illusion that you can get more done when, in actual fact, if you planned your day better and stayed focused… (you’ll) get more done.”

Stress, burnout and injury aren’t the only health risks — working more than 48 hours per week has also been correlated with “risky” alcohol consumption, according to a 2015 Finnish Institute of Occupational Health study of more than 300,000 people — which could result in additional health concerns. 

The same study also found links between long working hours and raised blood pressure and unhealthy diets. 

Employers that still push for long work hours are likely just uninformed about the potential risks, said Pencavel.

“Why would any employer that cares about profits, why would they ever set hours so long that it actually harms them? One would presume that it’s because they don’t know… they are not aware.”

Taking a thoughtful, balanced approach to the workday can create much higher productivity than simply cramming in as many hours as possible, said Kennedy.

“These people who work all these long hours, they’re kind of like martyrs. They don’t take their breaks, they don’t take their lunch — they just think if they work straight through, they’re going to get more done. But our brains need energy and nutrients to work best,” she said.

“So it’s really important — even if you just get up from your desk, grab a glass of water and go back, that does more than putting in an extra hour at the end of the day.”

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