It is estimated that around 30% of adults do not get enough sleep on a regular basis. To put it another way, their sleep need—the actual amount of sleep an individual needs to feel rested and function at their best—is not being met.
Sleep loss, as anyone who has gone to school or work on fewer hours of sleep than they need can tell you, has a number of consequences. Some of them, like increased sleepiness, slower reaction time and poor concentration can impair performance at work. But sleep loss can also influence physical health, leading to health issues such as an increased risk of developing chronic diseases. In fact it affects so many adults that the Centers for Disease Control and Prevention have labeled insufficient sleep a public health epidemic.
There are a lot of reasons why adults aren’t able to get sufficient sleep on a regular basis, some of which we can control and some of which we can’t. If insufficient sleep is the result of a medical condition, like sleep apnea or insomnia, treatment can help. But other factors that can lead to sleep loss, like poor work hours, are harder to control.
Sleep need is highly individual—some people need more sleep and others may need less. And sleep need can also change significantly depending on different circumstances. For instance, when you are ill, your sleep need may be different from when you are healthy.
And when we prefer to sleep—our circadian preference, which decides whether we are night owls or early birds—also varies between individuals. Circadian preference is strongly influenced by our genes, which means we have little control over whether it’s easier to wake up early or stay up late.
So if our sleep needs and circadian preferences vary so much, why does so much of the working world function on nine-to-five schedules? Night owls (who find it hard to go to bed earlier in the evening) will find their sleep truncated if they have to wake up early in the morning to go to work.
Rather than forcing all employees to fit to a “standard” work schedule, flexible work hours may allow individuals to sleep when they need and for as long as they need. This could also help reduce conflicts between work and family and social demands.
A recent study assessed whether flexible work hours could help employees get more sleep, and of better quality. Researchers used a workplace intervention that allowed employees to choose when and where (for instance, at home, in the office) they worked. The idea was to reduce the conflict between work and personal life, and see how it affected sleep.
Researchers hypothesized that allowing employees to be more flexible with their working schedule would lead to an increase in the amount and quality of sleep they got. Approximately half of the participants were randomly assigned to the intervention while the other half continued to work their normal schedule. Importantly, the total number of hours worked did not differ between the two groups.
Participants wore activity monitors to measure sleep quantity and quality for a total of two weeks—one baseline week at the start of the study and another week a year later. Participants were also interviewed about their sleep quality at baseline, six months and 12 months after the intervention.
Compared to people in the control group, employees in the intervention group increased their sleep by approximately one hour per week (eight minutes more each night) and their perception of sleep sufficiency improved.
It might be a small change, but any improvement in sleep duration and quality, no matter how small, is a move in the right direction towards reducing the sleep deficiency experienced by adults. Over time, this extra hour of sleep each week could lead to positive health effects.
Remember, the quality and quantity of sleep we get depends on a lot of factors. If you face a long commute to work, you may get up earlier than feels comfortable to make it into the office by a certain time. Or you might need to start your day earlier to leave the office in time to pick up kids from school.
Here it’s useful to look at employees’ interviews to gauge the impact of the flexible work arrangement. Employees in the intervention reported that having control over their work time allowed them to adjust their sleep which lead them to obtaining (to quote one employee) “more sleep than I’ve had in years.”
Subjective measures of sleep—such as how workers feel about how much sleep they get—may not always be as accurate as objective measures of how much sleep they actually get. But comments like this demonstrate how flexible work hours may improve how much people sleep.
While flexible working hours did not increase sleep duration significantly in the group studies, it is possible that any extra time gained by this flexibility was spent on family or social activities.
Although activities like going out with friends, or spending time with family can compete for sleep at times, these activities can also help to reduce stress, which in the long-term can improve sleep quantity and quality. Allowing flexible working hours may just be one part of the solution to increase sleep duration in adults.