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In Your Health today, we'll hear about new strategies for getting people off the couch. But first, the latest in sleep research. NPR's Allison Aubrey reports on how getting more sleep at night can improve everything from a 40-yard dash time to the vocabulary and the math skills of preschoolers.
ALLISON AUBREY: College is often a time of late nights and erratic sleep schedules, and athletes on campus don't seem to be much of an exception. Stanford sleep researcher Cheri Mah studied a group of football players on her campus and found surprising levels of daytime fatigue at the beginning of the season, even though the players thought they were getting adequate sleep.
So she was curious to know: If each of them added a couple of hours of sleep per night, how might that influence their performance?
Ms. CHERI MAH (Stanford Sleep Disorders Clinic): The goal is to aim for 10 hours of sleep at nighttime.
AUBREY: Wow. Ten hours. That's a lot to ask of a college football player. Yeah?
Ms. MAH: It's difficult. It definitely is difficult.
AUBREY: Throughout the season, she definitely got players sleeping more - not always the full 10 hours, but in each case a significant extension of nighttime Z's. And then she documented how these players performed on drills.
Take the 40-yard dash. Early in the season, the average time was 4.99 seconds. But after six weeks of getting more sleep each night...
Ms. MAH: We saw a drop in a tenth of a second, down to 4.89 seconds.
AUBREY: Hmm. So just a tenth of a second, I guess - is that a big deal?
Ms. MAH: A tenth of a second may sound small, but for many of these athletes, a tenth of a second is a huge difference.
AUBREY: And it's not just sleep researchers who agree on this point.
Dr. TIM CHURCH (Pennington Biomedical Research Center, Louisiana State University): Yeah. I mean, in the NFL, that's millions of dollars.
AUBREY: That's physician Tim Church of the Pennington Biomedical Research Center. He's both a fitness researcher and an athlete.
Dr. CHURCH: A tenth of a second in, you know, a 40-yard dash is a huge, huge difference from a performance standpoint.
AUBREY: But what Church says is just as significant is that these players' levels of daytime fatigue decreased significantly with more sleep, and their scores on vigor tests improved.
Dr. CHURCH: These are young individuals whose bodies have great capacity to grow and change, you know, in terms of adding muscle. And a lot of that stuff happens when you're sleeping. So it makes sense - you're young, you're training hard - that additional sleep's going to provide additional benefit.
AUBREY: So how might this connection between more sleep and improved physical performance translate to all of us who aren't collegiate athletes in top shape? Should we be catching more Z's in order to speed up a slow jogging or walking pace?
Dr. CHURCH: it's hard to translate these findings. I think the most important take-home thing is it is one more example that definitely, sleep makes a difference.
AUBREY: The benefits of adequate sleep extend far beyond what's now being documented on athletic performance. And when it comes to teaching good sleep hygiene, it seems you can never start too young.
New research being presented at a conference of sleep researchers this week explores the habits of preschool-age children to see how sleep may predict academic performance.
Dr. ERIKA GAYLOR (SRI International): It's a good time to look at things like early learning, brain development.
AUBREY: That's researcher Erika Gaylor of SRI International, a nonprofit research institute in Menlo Park, California. She analyzed a survey of some 8,000 families in which parents were repeatedly asked a slew of questions about bedtime from the time their kids were nine months through age four.
Dr. GAYLOR: They asked: What time do the children usually go to bed? What time do they usually wake up? And do you, as parents, have a rule about bedtime?
AUBREY: Researchers then completed one-on-one assessments of the children in their homes to measure math and language skills.
Dr. GAYLOR: So they asked them to point to pictures and tell stories and how can they count, and those kinds of things.
AUBREY: Gaylor says what she found is that sleep habits seem to have a unique contribution to four-year-olds' development.
Dr. GAYLOR: What was really surprising was having a rule about bedtime was associated with higher scores on language and math skills.
AUBREY: About 6 to 7 percent higher than children whose parents didn't have a rule about bedtime. It's a small but significant difference, and researchers say the study is yet another example of the power of a good night's sleep.
Allison Aubrey, NPR News.