A pair of new sleep studies -- one from Penn State and one from a European medical society -- have corroborated what clinicians at Strong Memorial Hospital’s Sleep Center said are already cornerstones of their medical practice.
The research findings can be summed up pretty simply: Screens (like those on laptops, tablets and smartphones) inhibit sleep, and exercise improves it.
“Screen time is probably the No. 1 thing I talk about when we talk about sleep with kids and adolescents,” said Laura Cardella, an assistant professor of psychiatry and pediatrics at the University of Rochester Medical Center.
Cardella said she often finds herself urging teens to use their phones less around bedtime, and exercise more throughout the day.
“It’s probably talked about every single appointment I have,” she said.
Orfeu Buxton, a professor at Penn State and a lead researcher on the study about how exercise affects teens’ sleep, said his team’s findings point to what researchers call a “dose effect”: A bigger dose of exercise means more sleep.
For every extra hour of exercise, teens fell asleep about 20 minutes earlier and slept 10 minutes longer, Buxton said. And while they were asleep, they slept more soundly.
Cardella said teens who don’t get enough good, sound sleep are at risk of a number of medical and social problems.
“Chronic sleep deprivation can increase risk for anxiety, depression, substance use, suicidal behavior, increased risk of motor vehicle accidents, decreased grades, problems with attention, concentration, memory, decreased physical health, increased risk of obesity, heart disease, diabetes,” she said. “The list goes on.”
Those risks have been growing over the last few years, and Cardella said research increasingly shows a causal relationship.
“The number of hours of sleep have been decreasing, and also, in the same time period, the risk of depression has increased, and suicidal ideation and suicide attempts and suicide completions have increased,” Cardella said.
Orfeu acknowledged that some of this research can seem obvious: When you exercise, you get tired, and when you get tired, you sleep better.
“Sometimes I think of my grandmother. Her recommendations were very simple, and she already knew them and didn’t need science for them,” Buxton said. “Get to sleep when you’re tired, stay active during the day, eat well, and do something to challenge yourself.”
But he said public health policies shouldn’t be based on assumptions. That’s why the scientific rigor matters.
“You know, some of the most important science that we do is by way of finally demonstrating the deadly obvious,” said Buxton. “Most of my research program is simply proving my grandma was right.”