A good night's sleep will do more than help you feel rested and refreshed. A new study suggests that getting more sleep will also reduce your sensitivity to pain.
"Our results suggest the importance of adequate sleep in various chronic pain conditions or in preparation for elective surgical procedures," said lead author Timothy Roehrs, PhD, of the Sleep Disorders and Research Center at Henry Ford Hospital in Detroit.
The small study by researchers at Henry Ford and Wayne State University involved 18 healthy, pain-free, and tired volunteers. They were randomly assigned to either four nights of their usual amount of sleep or an extended sleep period of 10 hours in bed per night.
The extended sleep group slept an average of 1.8 hours more per night. The added sleep not only increased their daytime alertness, it also reduced their sensitivity to pain in a heat test.
The well-rested group kept their finger on a radiant heat source 25 percent longer than the control group; even though the control group was given a 60 mg dose of codeine to dull their pain.
"We were surprised by the magnitude of the reduction in pain sensitivity, when compared to the reduction produced by taking codeine," said Roehers.
In the 1960s, average sleep duration was estimated to be about 8 hours a day; whereas by 2005 it was 7 hours or less. A recent national survey reported that 21% of the population slept 6 hours or less a day.
Researchers say a number of factors are contributing to this trend, including 24 hour access to entertainment, social and family responsibilities, time spent commuting, and around-the-clock demand for commercial services that require working overnight. By some estimates, up to 25 percent of the population suffers from sleep deprivation.
While some sleep disorders, such as obstructive sleep apnea and narcolepsy, stem from physiological conditions, for most people sleepiness is due to insufficient time in bed and reduced sleep time.
What's important, according to Roehrs, is that many of the medical problems caused by lack of sleep are reversible, and can be accomplished in a short period of time.
"The results of the current study indicate that a relatively short bedtime extension, four nights, is sufficient to provide benefit for alertness and pain sensitivity for individuals with this level of excessive sleepiness," he said.
Roehrs says this is the first study to show that extended sleep in mildly sleep deprived volunteers reduces their pain sensitivity. He adds that the results, combined with data from previous research, indicate that increased pain sensitivity in sleepy individuals is the result of their underlying sleepiness.
The study appears in the December issue of the peer-review, scientific journal SLEEP, which is published online by the Associated Professional Sleep Societies LLC, a joint venture of the American Academy of Sleep Medicine and the Sleep Research Society.