How daylight saving time can make you less productive, less ethical and more prone to injury at work

It's time to set your clocks back one full hour again, as daylight time comes to an end on Sunday, giving many outside the DST-free province of Saskatchewan, an extra hour of sleep this weekend.

And while many Canadians will welcome the additional time in bed, researchers say even small disruptions to our body clocks can have harmful effects, especially if they are repeated night after night.

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Chris Barnes researches sleep and is an associate professor of management in the Foster School of Business at the University of Washington. 

He spoke with Cost of Living host Paul Haavardsrud about sleep deprivation and how it affects your decisions at work. Here is part of their conversation.

Larks versus owls: Do most people share a similar circadian process or are we all different?

There is an archetype that we all share with this 24-hour cycle that has a few ups and downs across that period. 

However there are individual differences. Some people are shifted more to be in favour of mornings. We call them larks: people who like to get up early and go to bed early.

On the other end of the spectrum we have people that we call owls. Those are people who like to go to sleep late and wake up late. 

You can fight against those natural circadian processes but it's not easy.

When you try to force your body to sleep at a time that it doesn't really want to sleep, or force your body to be awake when it doesn't really want to be awake, you're gonna lose some efficiency there. 

You're going to have a harder time getting to sleep. You're going to have a harder time staying asleep. You will have a harder time being awake and being focused and having clear attention on what you're doing. 

How do sleep deficiencies manifest in the workplace?

One of my very first papers shows a spike in workplace injuries on the Monday right after the change to daylight saving time in the spring. 

On that second Monday in March, which we call "Sleepy Monday," employees show up with a little bit less sleep than they otherwise would. 

For that study I examined mining injuries in the United States over a 25-year period. That particular data set had over 500,000 mining injuries and we found that on Sleepy Monday many injuries went up by 5.6 per cent. 

When leaders get a bad night of sleep they come into work the next day and are more likely to mistreat their subordinates.- Sleep researcher Chris Barnes

This is a non-trivial increase in work injuries due to people not being able to concentrate as well, not being quite as focused at work, because they're a little bit more sleepy.

One of my favorite studies shows that when leaders get a bad night of sleep they come into work the next day and are more likely to mistreat their subordinates. Those subordinates, in turn, report lower levels of work engagement as a result. 

So what that study actually shows is that the sleep of one person can harm the work outcomes of other people.

What is cyberloafing?

Cyberloafing is when you are paid to be doing a task at work, you're on the clock, but instead you are doing non-work activities online.

Maybe you're checking your personal email. Maybe you're looking at cute kitten videos. Maybe you're looking at the latest online gossip. Whatever it is, it's not work related.

A lot of managers don't like cyberloafing because they think of it as time theft. 

Is cyberloafing time theft?

A lot of times people are cyberloafing because they need more breaks when they're sleepy. 

From a productivity aspect it's clear to see that people will probably spend less time working when they're sleepy than when they are rested, even within the same 8 a.m. to 5 p.m. time period. 

It's harder to stay focused on the job for a prolonged period of time when you are sleep-deprived. The mechanisms you have for directing your attention to a task are undermined when you don't sleep enough.

Willpower out the window: If we don't get enough sleep can we focus at work? 

Self-control is clearly connected to cyberloafing. 

That's why we see the increase in cyberloafing when people are sleepy. But that lack of self-control has so many other implications, even just when confined within the workplace. 

Some of my other research indicates that when people are sleep deprived, or have poor quality sleep, their ability to resist temptations to behave unethically is undermined. 

So we see that the same person can be more unethical on one day than on another day in part based on their sleep the previous night. 

When you're sleepy, it's harder to resist temptations.

How much sleep deprivation are we talking about?

In my research I like to look at relatively small amounts of sleep deprivation. 

It's obvious that if someone stays up for five days straight, with no sleep, all sorts of bad things are going to happen. 

But most of us assume those bad things won't happen if I miss maybe one- or two-hours of sleep here or there.

My research looks at small amounts of sleep deprivation.

I look at natural variation and sleep rather than extreme amounts of sleep deprivation. So I think the clearest way to look at how this manifests is to look at those effects on daylight saving time. 

In the spring when we lose that hour and come into work on "Sleepy Monday," not only do we see an increase in work injuries, we also see that people are lower in moral awareness which would be a precursor to unethical behaviour. We also see that they're higher in cyberloafing. 

So those three effects are all based on a one-hour change in the clock. 

So, if you can imagine telling yourself that missing a few hours is no big deal, and then I can show you data saying missing one hour actually does turn out to be a big deal, this makes the problem a little bit more clear.

Written and produced by Tracy Fuller. Q&A has been edited for length and clarity.