It's late at night, and as you are getting ready to turn out the light, you check your cell phone one last time, thinking you'll get a leg up on tomorrow. Bad idea, according to a pair of studies by researchers at Michigan State University.
Work with your phone tonight and you'll be less productive tomorrow.
The researchers found that the use of smartphones for business late at night (after 9 pm) by workers in all kinds of jobs — from nursing to manufacturing — cuts into a person' sleep and saps their energy on the job the next day. The use of phones was more disruptive to productivity than other electronic devices.
“Smartphones are almost perfectly designed to disrupt sleep,” said study author Russell Johnson in a statement. “Because they keep us mentally engaged late into the evening, they make it hard to detach from work so we can relax and fall asleep.”
Smartphones that emit blue light, which affects melatonin production, are the most sleep disruptive.
In both studies, people filled out daily surveys. The first study looked at upper-level managers, while the second surveyed a broad spectrum of workers that included accountants, dentists and mechanics.
Results from the two studies showed next day energy depletion from nighttime smartphone use. And the second study indicated a stronger negative effect from using a smartphone than from watching TV or using a tablet computer or laptop at night.
Johnson, an assistant professor of management in the Eli Broad College of Business at Michigan State, particularly singled out smartphones that emit blue light.
Blue is the color of light most disruptive to sleep because it suppresses the production of the hormone melatonin. Without enough melatonin, people find it difficult, or even impossible, to fall asleep.
Johnson admits he sleeps with his phone at his bedside, turned on, but one solution is to turn off the phone at night or put it in another room.
Doing what you can to protect your sleep is important. It's no secret that we live in a sleep-deprived society, and researchers continue to find new reasons why sleep is essential to good health.Recently it was confirmed that sleep serves the important function of helping the brain take out its trash, helping us stay sharp.
Smartphones are among the most important productivity aids ever invented. These studies, however, reveal their downside. Of course there are nights when you just have to get the job done. But in general, it seems that a good night's sleep may be the best road to success at work.
An article on both studies will appear in a future issue of Organizational Behavior and Human Decision Processes.