Several years ago, we put out a two-part series — episode Nos. 211 and 212 — called “The Economics of Sleep.” We looked at the relationship between sleep and health, both physical and cognitive.
David DINGES: You simply cannot think as fast and solve a problem as quickly when you’re sleep-deprived as when you’re not sleep-deprived.
And the relationship between sleep and income.
Lauren HALE: Generally, people who have more opportunities, more control over their lives, are also better sleepers.
None of these claims were particularly surprising — or at least they shouldn’t be. Anything the human body requires for one-third of its operating hours must be pretty important. What did surprise us was how little good, clean, real-world data there was on sleeping.
HALE: I realized that we have data on the social experiences of individuals from childhood to middle age or older ages and we were looking at what social factors explain health. And they had an enormous amount of data on these individuals on two-thirds of their lives — the waking hours. But they didn’t have anything on what’s going on during that remaining third at night.
Why don’t we have better sleep data?
Diane LAUDERDALE: It’s quite difficult to get accurate information about people’s routine sleep behavior.
What would it take to get that kind of information?
Matthew GIBSON: What we really need is something like an experiment for sleep.
We did learn about one sleep experiment that was just getting underway — in Chennai, India, a city of 10 million people. The researchers wanted to explore the relationship between sleep and labor productivity. Here’s the economist Heather Schofield:
Heather SCHOFIELD: If people are tired enough to be sleeping in the middle of the street in the 100-degree heat with trucks going by, it’s pretty hard for them to be as productive as possible in the labor force. So if we can help improve their sleep, our hypothesis is that it will very much improve their ability to work longer and work harder and work better.
Today, on Freakonomics Radio: we circle back to that experiment and tell you the findings.
Frank SCHILBACH: We were shocked initially to find these results.
Also, we explore a particular mode of sleep to see whether it can help:
Lois JAMES: There are some departments that have implemented napping policies.
“Napping policies”? Wait a minute, aren’t naps for 3-year-olds? How can you sell that to hard-charging adults?
Stephen JAMES: We call it the alertness edge.
Is it time for everyone to take a nap? That’s coming up, right after this.
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This is one of those episodes that, I’ll be honest, may say more about me than you. But I hope that’s not the case. The thing is: I love to sleep, and I’m pretty good at it. Sleeping is not an Olympic sport — yet — but if that ever happens, I’m pretty sure I’ll medal. I also love to nap, just about every day, usually around 25 minutes. It’s one of the reasons I became a writer, one of the reasons I didn’t want to work in an office. I really love that nap. I depend on that nap. A day without a nap is — well, it’s too long, it’s too exhausting, physically and mentally. A day with a nap, meanwhile — it’s really two days in one. The morning day, with its own rhythms and rituals; then the afternoon day, with a different rhythm. Given my enthusiasm for sleep, I pay a fair amount of attention to what the research has to say about its benefits. There is by now a large body of work showing that sleep is essential to good physical and mental health. Again, not so surprising. What may surprise you is some of the research on sleep deficits.
As I mentioned earlier, good sleep data are hard to come by. A lot of the data are self-reported; also, a lot of small sample sizes. Some of the more reliable research has to do with work and productivity, where the sample sizes are larger and where, frankly, there’s more incentive to measure well. Studies have shown that sleep-deprived people can make more errors and have a hard time fending off distraction. Also, creativity can suffer. Other studies show a relationship between poor sleep and unethical behavior, like cheating. And if you want to look bigger picture: there is research showing that sleep deprivation costs the U.S. more than $400 billion a year in economic losses; that’s more than 2 percent of G.D.P. The pandemic has obviously scrambled a lot of people’s sleep patterns. People who no longer had to commute had more time at home and some of them certainly got more sleep. On the other hand, anxiety and stress can hurt your sleep, and the pandemic provided plenty of that. We often hear that most of us just don’t get enough sleep — although the actual evidence for that isn’t so clear. What we do know — or at least what we’re starting to learn — is that there’s quite a bit of variance in how people sleep best. Some of us are night owls; others are morning larks, ready to go at sunrise or even before.
S. JAMES: It’s funny because Lois and I, being a married couple, are typically the extremes across most of the variance in how people tolerate sleep. Lois is a long sleeper, who’s a lark and typically always been a lark. When she gets her sleep, she’s brilliant. When she gets less sleep, it’s like living with a grizzly bear.
L. JAMES: I resemble that comment.
S. JAMES: I’m on the shorter sleep end of the spectrum. I handle sleep disruption pretty well.
DUBNER: At least you think you do.
S. JAMES: At least I think I do. Yes, that is really, really a good point.
Lois and Stephen James are sleep researchers and professors at Washington State University’s College of Nursing.
S. JAMES: We try to understand the impact of stressors — most prominently sleep-related fatigue and shift-work-related fatigue — on operational performance for a range of occupations where the cost of getting it wrong is high. So we work with military, law enforcement, nurses, and to a lesser extent, elite athletes.
DUBNER: You mentioned military, law enforcement, nurses — those come to mind as professions where I haven’t heard a lot about sleep requirements. But then there are professions like aviation and even firefighting where sleep is kind of baked into the work pattern. So is there a lot of variance in the professions about how much attention they pay to sleep?
L. JAMES: There’s a great deal of variance, and there are several things that factor into that. One is shift length. So traditionally, the professional groups that have longer shifts have been a little bit more open to managing fatigue and sleep requirements. So, for example, physicians and aviation and firefighting typically work longer shifts than police officers and nurses who, in theory, would have about a 12-hour max. But the other big component, I think, is cultural. There are some real cultural differences in terms of acceptance of self-care, and stigmatizing about fatigue.
S. JAMES: Yeah, the military actually launched a new field manual highlighting sleep as an important factor in maintaining operational readiness. And although it’s true that a firefighter — there’s a culture of sleeping because of their 24-, 48-, 96-hour shifts — with E.M.S., who often share the same organization or the same base location, sleeping on shift or napping on shift is far less common.
DUBNER: So how does that make sense, or it just doesn’t? It’s just an accident of history, essentially?
S. JAMES: Partially that, yeah. But also, the idea of being proactive versus responsive. You know, we expect our cops to be out on the street patrolling, deterring crime, whereas firefighters are responsive.
The Jameses say that of all the vocations they’ve studied, professional athletes are among the most enthusiastic about sleep and even napping.
L. JAMES: Absolutely.
The Olympic skier Mikaela Shiffrin; the Olympic swimmer Ryan Lochte; the N.B.A. legend LeBron James: they are all famously fond of napping.
L. JAMES: The athletes, I find, are typically fantastic to work with because obviously they’re extremely motivated to get good sleep and to manage fatigue. And, they’re extremely well-supported.
S. JAMES: So often we use our work with athletes to then go and talk to law enforcement. To say, “Hey, look, it’s not weakness.” You know, it’s not weakness to say, “I’m too tired, I need a break.” You’re being a professional and you’re maximizing. So we call it the alertness edge.
L. JAMES: It’s a cultural shift for sure, thinking of sleep as a strength.
When you think about the relationship between sleep and a given profession, policing presents a series of particularly thorny issues. It’s got long periods of relative calm that still require alertness — which are punctuated, randomly, by encounters that may be extremely stressful or even dangerous.
S. JAMES: You know, we talk about the criminal-justice system, but we do need to be mindful that the system is made up of human beings with the same limits on their resources that we all have. So not to discount or make excuses or try and play down the responsibility of a police officer to get things right, to make a good decision, but we also need to understand the impact of fatigue, and so on, so we can create policies and training and procedures and countermeasures to help support the individual in whatever operational setting they’re in.
There’s also the fact that policing requires shiftwork, including the overnight shift.
L. JAMES: About 50 percent of officers report falling asleep at the wheel, and about 25 percent fall asleep a couple of times a month at the wheel.
DUBNER: And how do those numbers compare to, say, an office worker, a plumber?
L. JAMES: They’re quite a lot higher. They’re comparable to other shift-working populations. But they’re a lot higher than members of the general public.
S. JAMES: A police officer, if they’re on an eight-, 10-, 12-hour shift, if they’re on a patrol duty, will spend the vast majority of their time driving. And to add to that really dangerous mix is the fact that they have a ton of technology in their cockpit and almost every state exempts them from distracted driving laws. It’s a perfect storm.
DUBNER: It strikes me that the problem is not just that you’re working a lot of hours in a stressful situation, but you’re working a lot of hours at night. And the more that scientists learn about circadian rhythms, the more we learn that biology is different through the course of day. Do you know much about how influential nighttime work is per se?
S. JAMES: Absolutely. We’re diurnal animals. We are biologically designed to operate during the day and sleep at night. And anything we do counter to that comes at a cost, whether it’s to our health or to our safety or performance.
Around the world, an estimated one in five workers regularly works at night, on what’s sometimes called the graveyard shift. The World Health Organization has called night-shift work a probable carcinogen. There are at least two major reasons why night work is so hard on the body. The first, as I mentioned above, is our circadian rhythm — our natural body clock, which for most people generally means being awake during the day and sleeping at night. Messing with that can trigger not only sleep disorders but other problems like obesity and depression. But also: when you work at night, you have to sleep during the day, and our bodies and brains aren’t primed to do that; so the quality of daytime sleep is typically worse than nighttime sleep. Lois and Stephen James have been studying these issues empirically, in the realm of policing especially, in their lab at Washington State.
S. JAMES: I have large wraparound driving simulators, the type that law enforcement train on. And we have multiple use-of-force simulators, which are rooms dedicated to encounters with the public.
DUBNER: So there’s essentially a room where you can simulate any kind of disturbance or event that might require police attention, yes?
L. JAMES: Yeah, so within the use-of-force simulators, we actually custom-make our own scenarios. The first set, I think, were developed back in 2009. And those are quite traditional “shoot, don’t shoot” scenarios.
DUBNER: And the visuals are what?
L. JAMES: They’re seeing like a live-action video, essentially. So video scenarios that we filmed with professional paid actors in naturalistic settings based on data from police-citizen interactions. So an example is a domestic disturbance where officers arrived to the scene. It’s quite volatile. A man and a woman are shouting at each other, hands on each other, and the officer needs to step in and try and de-escalate. And the scenario can unfold a number of ways based on the actions of the officer.
DUBNER: And do you have different versions of this scenario filmed, that mix up race, age, or anything like that?
L. JAMES: Yes, we do. In addition to sleep research, my major area of work, and Steve’s as well, is in implicit bias. So these scenarios are all designed to be able to tease apart motivations on officers’ decision-making.
This is what the Jameses are really after: the connection between decision-making and sleep.
S. JAMES: In our research, when we’re brought officers into the lab from four different shifts, we found that even 72 hours off-shift — so they’ve had 72 hours of rest — the graveyard-shift officers’ performance was worse than the fatigued day-shift officers because of their chronic level of fatigue. And even 72 hours off is not enough time to recuperate.
DUBNER: Is it possible that the police officers who either choose to work the graveyard shift or are assigned the graveyard shift have different characteristics than the population of police officers who are working daytime?
S. JAMES: That’s true to some extent. The vast majority of agencies have a bid for shift based on seniority. So when you come out of the academy, go through your field training, you then get assigned to whatever shift needs you, and that’s predominantly the graveyard shift.
DUBNER: So less-experienced police officers typically tend to be on the graveyard shift.
S. JAMES: Yeah. So there is a small cohort of officers who like it, who opt for the graveyard shift. And when speaking with them, they say things like, “Well, the day shift deals with victims and we get to deal with criminals.” That kind of mentality. And we’ve worked with officers who have spent 20, 30 years on graveyard shift.
L. JAMES: And to that point, there’s also great individual difference in chronotype or chronobiology, which is how much of a morning or an evening person you are. And the people who are extreme evening persons or night owls would actually have a harder time on the day shift than they would on a night shift if the day shift starts quite early. And people who are naturally inclined to be morning people are going to have a horrendously hard time on night shift. So there is a push now to actually factor in chronotype when shift scheduling and assigning shifts.
DUBNER: Is napping a common practice in any police departments that you know of?
L. JAMES: There are some departments that have implemented napping policies, but I would say it’s still considered to be an impossibility for most. As far as I’m aware, those that have implemented policies are not all that formal.
DUBNER: Let’s say I bring the two of you in to consult for the New York Police Department, and I say, “I’m persuaded that fatigue is a major downside of policing generally and it’s a major contributor for anyone, not just police officers, to bad decision-making and things like that. The science seems pretty plain on that.” And I say, “I can’t really control how well and long my police officers sleep when they’re home because that’s their environment. But what I can do is make sure that I give them an opportunity to catch up or to not be fatigued when they’re here. So I’m going to take the whole third floor of my building and make it nap cubicles. And I’m going to require — or heavily suggest — that everybody naps once during their shift for 20 or 30 minutes. What would you expect would be the response to that? And what would you expect would be the results?
L. JAMES: First, I would say, you’re hired.
S. JAMES: Well, the evidence out there for napping improving performance — it’s there, but it’s limited in a way. All of the studies that I’ve seen around the efficacy of napping on duty, whatever that occupation is — whether it’s firefighting, E.M.S., policing — shows that, yes, it supports things like psychomotor vigilance tests. You know, reaction time. It allows the officers or the worker to feel better. We’re still waiting for that study that shows it improves operational performance. And that is kind of where I see what we need to really do — does it actually make it safer for the community and for the officer?
L. JAMES: Fatigue-management training isn’t necessarily just beneficial for the health and wellness of officers. It is also potentially impactful for public safety and police-community relationships.
DUBNER: Look, I’m on your team. I’m on Team Sleep by a long shot. But I can see that a lot of people just have a baseline response that “Sleep is for the lazy and that’s not me. I’m strong and I’m not going to waste my time with that.”
S. JAMES: Greg Belenky, who’s one of our mentors, when he was at Walter Reed Army Institute, he did one of the most important studies I use to convince people about the need. He took a group and he put them through different cohorts of sleep restriction. Some got nine hours. Some got seven. Some got five hours. Some got three. The nines maintain their performance; the sevens dipped a little and then leveled out at about 90, 95 percent of their performance. But the fives dropped down to around about 80, 85 percent of their baseline performance. And then the three-hour cohort continually declined. And when I speak to law enforcement, I use the diagrams from that study to say, “Hey, 80 percent may be okay in some professions, but I don’t believe you’re in an 80 percent profession.”
Are you in an 80-percent profession? Even if you are — even if you’re in a 60-percent profession — wouldn’t you like to be better? Wouldn’t you like to know how more sleep, even a little bit more, might affect your work? And the rest of your life
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In the episodes we did on sleep a few years ago, the economist Heather Schofield told us about an experiment she and her colleagues were just starting in Chennai, India. The focus was sleep and productivity.
SCHOFIELD: Basically, we’ll conduct a lottery and half the people in the study will be given things to help them sleep better at night. In addition to that, we’ll also ask them to take a nap in the office every day.
They chose Chennai in part because it has so many factors that conspire against good sleep.
SCHILBACH: It’s really hot. Not many people have A.C. It’s noisy.
That’s Frank Schilbach. He’s an economist at M.I.T., and one of Schofield’s partners in this research.
SCHILBACH: It’s extremely loud. It’s crowded. People also mentioned psychological factors such as worry, stress, anxiety that interfere with their sleep.
So Schilbach, Schofield, their colleagues Gautam Rao, Mattie Toma, and Pedro Bessone, set up a randomized control trial in Chennai. There were three main questions they wanted to answer.
SCHILBACH: We really wanted to, first, objectively measure how much are people actually sleeping, and how prevalent is sleep deprivation in a fairly representative sample in urban India?
The second question?
SCHILBACH: What kinds of things could we do to improve people’s sleep, and what impacts would these interventions have on people’s lives?
And the third question:
SCHILBACH: If there are large effects of sleep, why is it that people are sleeping so little?
For this experiment, they recruited around 450 low-income adults and had them do data-entry work for one month. To answer the first question — how much sleep were these folks regularly getting? — the researchers outfitted everyone with a wearable sleep monitor called an ActiGraph. What’d they find?
SCHILBACH: Our first main finding is that people sleep only 5.5 hours per night. That’s way below what sleep experts would tell you, which is you’re supposed to sleep seven to nine hours a night.
DUBNER: I’m guessing you surveyed these subjects as well. Did they suspect that they slept much more than 5.5 hours?
SCHILBACH: Yes, and this is a common result in the sleep literature. People tend to think that they sleep a lot more than they actually do. This is often because people confuse how much time you actually spend in bed versus time asleep. Now, in our setting, there’s a huge, stark contrast between those two things. People actually spend about eight hours in bed, which is what people in the U.S. would do as well.
The percentage of time in bed that’s actually spent sleeping is called sleep efficiency. The average sleep efficiency in high-income countries is 85 to 95 percent. But in Chennai—.
SCHILBACH: They only sleep 5.5 hours, which tells you there’s a sleep efficiency of about 70 percent. And sleep experts or doctors will tell you if your sleep efficiency is below 85 percent, you’re having sleep problems.
Okay, so the people in this experiment weren’t getting very much sleep. On to question No. 2: could their sleep be improved? And if so, how would that affect their productivity? This is where the randomization comes in: there was a treatment group and a control group. For the treatment group, Schilbach and his team distributed a variety of sleep aids.
SCHILBACH: A mattress, ear plugs, eyeshades, table fan, blanket, pillow.
The treatment group also got information about the benefits of sleep.
SCHILBACH: Things like, you shouldn’t drink caffeine late in the afternoon, try to use the bathroom before going to sleep, try to have regular sleep schedules, and so on.
Schilbach and his colleagues, being economists, also tried financial incentives.
SCHILBACH: We measured people’s sleep for about a week. And then, we would tell people, going forward, if you increase your sleep by up to two hours, for every minute that you increase your sleep, we’re going to pay you one rupee, up to 60 rupees per hour, which is about a dollar.
And there was one more intervention.
SCHILBACH: We cross-randomized a nap intervention, which means some people got the night sleep intervention only, some people got the nap intervention only, and some people got both.
Every day between 1:30 and 2:00 in the afternoon, the lucky people assigned to the nap intervention were provided a private space in the office where they were doing their data-entry work. They were given everything you’d need for a good nap: a bed, a fan, earplugs, eyeshades.
SCHILBACH: And the idea was just naps would provide some very clean variation in sleep because you can essentially control when people nap and how much they nap.
Okay, let’s hear some results from this big experiment. How effective were the nighttime sleep interventions — the sleep information, the financial incentives, and all the sleep aids?
SCHILBACH: So, when you do all of those things, people in fact sleep about 30 minutes per night more over the course of three, four weeks.
And how does that compare to previous sleep experiments?
SCHILBACH: So, 30 minutes’ increase in sleep is actually quite a bit compared to other experiments. Now, interestingly, the increase in sleep is not coming from increased sleep efficiency. Instead, people just spent more time in bed. So, instead of spending like eight hours in bed, they spend about eight hours and 40 minutes in bed. And out of those 40 minutes, they actually sleep 30 minutes more.
So that’s interesting: more sleep but not more efficient sleep. Okay, what about work productivity? The researchers measured productivity by how fast and accurately these people were typing data into their computer, how many breaks they took, and so on. Did that extra sleep lead to higher productivity?
SCHILBACH: So, for night sleep, you eventually find no effect whatsoever on these productivity measures. There’s some slight positive effects, but these are not statistically significant. At the same time, you find relatively clear reductions in labor supply. People just spend less time at the office, and therefore, also less time typing. Putting these things together, people’s earnings go down a bit. Again, that’s not statistically significant. So, it’s not like we can say people increasing sleep reduce their earnings. But surely, we can reject the notion that, in contrast to our own predictions, people are not increasing their earnings by sleeping more at night.
DUBNER: That sounds like you’re actually decreasing their productivity. You’re trying to get them to sleep, “better” in order to increase their work productivity, to earn more money. But in fact, by sending them these nice mattresses and other things, you’re actually just getting them to spend more time in bed, which means that they’re spending less time at work, which means that their incomes, I assume, are not rising?
SCHILBACH: Exactly. That was very surprising to us. And we were shocked initially to find these results. I should say we also had some expert surveys in advance where we asked economists and sleep scientists to predict what might happen. And what almost everybody, including myself, to be fair, predicted was that productivity — so, output per hour — would increase. But most experts also predicted that work hours would go up. And the idea was maybe you’re less tired. You could spend a little bit more time at the office and so on. But instead, we find none of that.
Now, you might think — isn’t it just like an economist to care so much about labor productivity? What about all the other benefits of sleep? Schilbach and his team did look at some other outcomes.
SCHILBACH: We measure their physical health, psychological well-being, decision-making, cognition, attention, memory, and so on.
SCHILBACH: We find no significant positive impact on any of these outcomes.
So in this experimental setting, at least, with this population getting these sleep interventions, Frank Schilbach and his team essentially failed to move the needle. Through a lot of effort and expense, they were able to get their subjects to sleep a bit more, but that extra sleep didn’t seem to materially improve anything. Except for one last intervention. You remember the lucky group that was randomized into nap duty?
SCHILBACH: When you compare people in our study who were randomized to receive naps, versus the control group, we find significant impacts on a range of outcomes, including pretty much all of the things that I just told you we didn’t find effective night sleep on. People produce more per hour worked. People are happier. People say they’re healthier. People have better attention and improved cognition.
And how did a nap affect these workers’ earnings? After all, they’re taking a half-hour snooze during the workday.
SCHILBACH: Here, it depends a lot on whom you are comparing the nappers to. If you compare nappers to people who just take a break, naps look great. People are earning more money. People are working slightly more.
But: there’s less of a difference when you compare nappers to people who didn’t get a break at all.
SCHILBACH: And that’s because people lose 30 minutes of their workday in the middle of the day. If you think your afternoon is about five hours of work and you lose 30 minutes, that’s about 10 percent. And the effects of naps are by no means as large as that.
Still, compared to the other sleep interventions the researchers tried, napping looks like a good deal.
SCHILBACH: Yeah. So, just to give some background, increasing productivity in tasks where people need to put in effort at work, is fairly hard. And so, the main insight here is that if you increase people’s wages, you tend to not find large effects on their productivity. So the effects of naps are remarkable.
But why would a short daytime nap succeed where more sleep at night failed?
SCHILBACH: One explanation is that naps are just different. Naps are in the afternoon. A night sleep is at night. Obviously that’s different times of the day, which might affect people differently. The competing explanation, which, if you ask me personally, I think is probably going on, is that the naps that we offer in our study are at our study office, at the workplace. And they get a pretty comfortable nap environment, where there’s very little sound, it’s quiet.
In other words, sleep quality in a cool, quiet environment is likely higher than the quality of sleep these same workers were getting at home — the hotter, noisier, more crowded homes that sparked this sleep study in the first place.
SCHILBACH: So, that tells us, well, what we were doing people cannot necessarily replicate on their own. Some employers might be able to do it, but the typical low-income worker in Chennai is not able to, in fact, do that.
This may also explain why these Chennai findings differ from other sleep studies that do find gains in productivity and cognition.
SCHILBACH: I still think that some of the effects of sleep on mental health and well-being in the long run might be really important. But I think it’s really important to do field studies in a range of settings, to understand whether the effects that are found in sleep labs extrapolate to these real-world settings where people sleep in their homes and go about their lives and when we really do policy-relevant interventions where we increase people’s sleep among people who we think are sleep-deprived. And the sleep literature is not quite doing that yet. Now, I myself still nap quite a bit, and I am a believer in napping. Not sure that’s necessarily for improving productivity, but perhaps just to improve my own well-being.
Some cultures, of course, do embrace the afternoon nap, or siesta. Some countries even allow their airline pilots to take naps in the cockpit — with restrictions, of course. There has been earlier research that shows the cognitive and physiological benefits of naps. Researchers from the University of Athens Medical School, for instance, found that when people stopped napping regularly, their health declined.
DUBNER: Let’s assume that after this conversation and many other conversations that people who run institutions decide that, “Oh my goodness, the gains from napping are large” — whether it’s the U.S. Army, police forces, teachers, medical professionals, or people working in any job, really — and that “everybody should nap.” Can you imagine an environment where naps are, “mandatory,” but people try to game the system in order to keep getting ahead?
SCHILBACH: So, the issue is you can’t force somebody to nap, of course. I’d like to emphasize that what we did was, in some sense, that’s not maximizing the impact of naps, because we had just had a treatment group and a control group where in the treatment group, everybody was napping or at least offered the opportunity to nap. But, there are some people who are just not good nappers, or some people just don’t want a nap on any given day. So, if we let people select into napping on some days versus not on others, or some people just maybe don’t want to nap at all, you might actually get more benefits of napping for the people for whom it’s most effective.
DUBNER: Let’s say you, Frank, became the U.S.’s napping czar. Who would you suggest as the public-facing person to endorse napping to help most cut back on any stigma that non-nappers might have?
SCHILBACH: I’m not sure about a figurehead per se. But I think it’s telling that tech companies, for example, are embracing napping quite a bit. You know, there’s all these nap cabins at a bunch of different companies. So, that’s one really good signal. Second, I think sports — there’s lots of N.B.A. or other athletes who seem to be sleeping a lot, including napping. And so, if suddenly, very highly respected sports stars are starting to nap, I think that could really influence people and, in particular, young people who might not necessarily want to nap otherwise.
But Schilbach thinks there needs to be a concerted focus on the main, underlying problem: it’s not just that some people need to sleep more; they need higher-quality sleep, whether it’s at night or during a daytime nap. And that suggests a wider set of solutions.
SCHILBACH: One is housing policies, noise regulation, or just trying even harder than we did to try to get people to take up devices that might improve their sleep quality, such as ear plugs, which are just hard to get people to actually use. Second, there could be also psychological interventions to try to reduce people’s stress and anxiety and just help people sleep better at night for a given sleep environment. And so, if we just figured out some way to improve sleep quality, my prediction and my hope is that perhaps we will in fact find larger effects on a number of outcomes that we were hoping to affect in the first place.
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Freakonomics Radio is produced by Stitcher and Renbud Radio. This episode was produced by Daphne Chen and Mary Diduch. Our staff also includes Alison Craiglow, Greg Rippin, Joel Meyer, Tricia Bobeda, Rebecca Lee Douglas, Zack Lapinski, Morgan Levey, Brent Katz, Emma Tyrrell, Lyric Bowditch, Jasmin Klinger, and Jacob Clemente. Our theme song is “Mr. Fortune,” by the Hitchhikers; the rest of the music this week was composed by Luis Guerra. You can follow Freakonomics Radio on Apple Podcasts, Spotify, Stitcher, or wherever you get your podcasts.
- Lois James, associate professor in the Washington State University College of Nursing; research advisor for the International Association of Chiefs of Police; and founding director of Counter Bias Training Simulation.
- Stephen James, assistant professor and researcher in the Washington State University College of Nursing.
- Frank Schilbach, professor of economics at the Massachusetts Institute of Technology.
- Heather Schofield, assistant professor of medical ethics and health policy at the University of Pennsylvania.
- “The Economic Consequences of Increasing Sleep Among the Urban Poor,” by Pedro Bessone, Gautam Rao, Frank Schilbach, Heather Schofield, and Mattie Toma (The Quarterly Journal of Economics, 2021).
- “Mitigating Fatigue on the Flight Deck: How Is Controlled Rest Used in Practice?” by Cassie J. Hilditch, Lucia Arsintescu, Kevin B. Gregory, and Erin E. Flynn-Evans (Chronobiology International, 2020).
- “The Pandemic Is Ruining Our Sleep. Experts Say ‘Coronasomnia’ Could Imperil Public Health,” by Karin Brulliard and William Wan (The Washington Post, 2020).
- “60 Million Fewer Commuting Hours Per Day: How Americans Use Time Saved By Working From Home,” by Jose Maria Barrero, Nick Bloom and Steven J. Davis (B.F.I. Working Paper, 2020).
- “Reducing Violent Incidents between Police Officers and People with Psychiatric or Substance Use Disorders,” by Harold A. Pollack and Keith Humphreys (AAPSS, 2020).
- “EMS Disordered Sleep And Work Schedule,” by James A. Bardinelli, Joseph Roarty, and Scott Goldstein (StatPearls, 2020).
- “The Army Rolls Out a New Weapon: Strategic Napping,” by Dave Philipps (The New York Times, 2020).
- “Army Gives Its Official Support to the Time-Honored Practice of Field Napping,” by Matthew Cox (Military.com, 2020).
- “FM 7-22 Holistic Health and Fitness,” by the Department of the Army (2020).
- “Law Enforcement’s Role in Distracted Driving,” by Howard B. Hall, Janet Brooking, and Rich Jacobs (Police Chief Magazine, 2020).
- Night Shift Work: IARC Monographs on the Identification of Carcinogenic Hazards to Humans Volume 124, by the International Agency for Research on Cancer of the World Health Organization (2019).
- “Nine Days on the Road. Average Commute Time Reached a New Record Last Year,” by Christopher Ingraham (The Washington Post, 2019).
- “How Your Sleep Can Impact Distraction Levels,” by Michael J. Breus (Psychology Today, 2019).
- “Working Americans Are Getting Less Sleep, Especially Those Who Save Our Lives,” by Morning Edition (NPR, 2019).
- “Effects of Sleep Deprivation on Procedural Errors,” by M. E. Stepan, K. M. Fenn, and E. M. Altmann (Journal of Experimental Psychology: General, 2019).
- “Medical Errors Are More Likely When Sleep Deprivation Occurs,” by Elise Oberliesen (Distance CME, 2019).
- “Why Healthy Sleep is Good for Business,” by Christopher M.Barnes and Nathaniel F.Watson (Sleep Medicine Reviews, 2019).
- “To Improve Air Safety, Let Pilots Nap in the Cockpit,” by Scott Winter and Stephen Rice (Fast Company, 2019).
- “The Impact of Work Shift and Fatigue on Police Officer Response in Simulated Interactions with Citizens,” by Lois James, Stephen M. James, and Bryan J. Vila (Journal of Experimental Criminology, 2018).
- “LeBron James Reveals the Nighttime Routine That Helps Him Perform ‘At the Highest Level,’” by Courtney Connley (CNBC, 2018).
- “Olympian Mikaela Shiffrin, the Top Slalom Skier in the World, Is Insanely Dedicated to Napping — and It Could Help Explain Why She’s So Successful,” by Kevin Loria (Business Insider, 2018).
- “Clocking Off: The Companies Introducing Nap Time to the Workplace,” by Anne Cassidy (The Guardian, 2017).
- “Tired Henderson Cops Told to Take Naps,” by Sandy Lopez (Las Vegas Review-Journal, 2017).
- “Cops Feeling Fatigued: There’s a Nap for That,” by Doug Wyllie (Police1, 2017).
- Why Sleep Matters: Quantifying the Economic Costs of Insufficient Sleep, by Marco Hafner, Martin Stepanek, Jirka Taylor, Wendy M. Troxel, and Christian Van Stolk (2016).
- “1 in 3 Adults Don’t Get Enough Sleep,” by the Centers for Disease Control and Prevention (2016).
- “Olympic Swimmer Ryan Lochte Explains Art of Napping,” by Nicole Auerbach (USA Today, 2016).
- “Time Use and Productivity: The Wage Returns to Sleep,” by Matthew Gibson and Jeffrey Shrader (UC San Diego: Department of Economics, 2014).
- “Fatigue on the Flight Deck: The Consequences of Sleep Loss and the Benefits of Napping,” by Beth M.Hartzler (Accident Analysis & Prevention, 2014).
- “The Benefits of Slumber: Why You Need a Good Night’s Sleep,” by the National Institutes of Health (NIH News in Health, 2013).
- “Napping on Game Day Is Prevalent Among N.B.A. Players,” by Jonathan Abrams (The New York Times, 20110.
- “Sleep Disorders, Health, and Safety in Police Officers,” by Shantha M W Rajaratnam, Laura K Barger, Steven W Lockley, Steven A Shea, Wei Wang, Christopher P Landrigan, Conor S O’Brien, Salim Qadri, Jason P Sullivan, Brian E Cade, Lawrence J Epstein, David P White, and Charles A Czeisler (JAMA, 2011).
- “Lack of Sleep and Unethical Conduct,” by Christopher M. Barnes, John Schaubroeck, Megan Huth, and Sonia Ghumman (Organizational Behavior and Human Decision Processes, 2011).
- “We Spend About One-Third of Our Life Either Sleeping or Attempting to Do So,” by Michael J. Aminoff, François Boller, and Dick F. Swaab (Handbook of Clinical Neurology, 2011).
- “The Cost of Poor Sleep: Workplace Productivity Loss and Associated Costs,” by Mark R. Rosekind, Kevin B. Gregory, Melissa M. Mallis, Summer L. Brandt, Brian Seal, and Debra Lerner (Journal of Occupational and Environmental Medicine, 2010).
- “Siesta in Healthy Adults and Coronary Mortality in the General Population,” by Androniki Naska, Eleni Oikonomou, Antonia Trichopoulou, Theodora Psaltopoulou, and Dimitrios Trichopoulos (The Archives of Internal Medicine, 2007).
- “WHO Study Links Night Shift Work, Firefighting to Cancer,” by Laura Walter (EHS Today, 2007).
- “Individual Variation and the Genetics of Sleep,” by the Division of Sleep Medicine at Harvard Medical School (2007).
- “New Study Shows People Sleep Even Less Than They Think,” by ScienceDaily (ScienceDaily, 2006).
- “Patterns of Performance Degradation and Restoration During Sleep Restriction and Subsequent Recovery: A Sleep Dose-Response Study,” by Gregory Belenky, Nancy J. Wesensten, David R. Thorne, Maria L. Thomas, Helen C. Sing, Daniel P. Redmond, Michael B. Russo, and Thomas J. Balkin (Journal of Sleep Research, 2003).
- “Driver Drowsiness — Are Physicians at a Special Risk?” by Shmuel Steier, Shlomo Vinker, Natali Bentov, Ayala Lev, and Eliezer Kitai (Harefuah, 2003).
- “The Economics of Sleep, Part 1 (Ep. 211 Rebroadcast),” by Freakonomics Radio (2016).
- “The Economics of Sleep, Part 2 (Ep. 212 Rebroadcast),” by Freakonomics Radio (2016).