July 20, 2000 -- Researchers at the University of Memphis found that teaching a relaxation technique to college students with insomnia could help them sleep. But they also found that improved sleep did not, in turn, help these students function any better the next day.
Researcher Melanie K. Means tells WebMD that while most sleep studies focus on improving the quality of sleep, there hasn't been as much research on the effect of a good night's sleep on daytime performance. "The belief is if sleep improves, so will performance," says Means, a graduate student in the university's psychology department. "We weren't so sure that was so."
In the National Sleep Foundation's 1999 survey, "Sleep in America," 62% of adult Americans reported having slept poorly during the past year. Of those, only 4% said they were seeing a doctor or other health care provider for advice or treatment. According to the survey, 56% reported experiencing one or more symptoms of insomnia, including difficulty falling asleep, waking during the night, waking too early, and awaking feeling unrefreshed.
College students, as a group, are known for poor sleep. For the Memphis study, the researchers recruited 118 undergraduate psychology students, just under half of whom complained of insomnia. The 57 insomniacs were further divided into two groups: 28 were given instructions in programmed relaxation, while the rest received no treatment.
The students in the study ranged from 17 to 44 years old, with an average age of 21. Those in the insomnia group had been experiencing sleep difficulties for an average of just more than 3 1/2 years. Nearly 70% of the students with insomnia were female, which is not surprising. The National Sleep Foundation estimates that 40% or more of females have trouble sleeping, compared to 30% of males. Their greater incidence of sleep problems may be at least partially due to hormonal shifts from menstruation, and later from pregnancy and menopause.
For the study, which was published in the journal Behavior Research and Therapy, students were considered to be suffering from insomnia if they had sleep problems lasting at least two months, including:
- trouble falling asleep
- waking up during the night
- waking earlier than they wanted
- dissatisfaction with sleep
- inability to function the next day due to tiredness
James Walsh, PhD, National Sleep Foundation Insomnia Council, says people who consistently lack sound, quality sleep experience a significant level of performance problems during the day. "We know that people who are sleepy are less productive and more prone to accidents -- on the road and at home," says Walsh, executive director of St. Luke's Hospital Sleep Medicine and Research Center in St. Louis and of the National Sleep Foundation's Insomnia Council.
The National Institutes of Health says insomnia is not defined by the number of hours of sleep a person gets or how long it takes to fall asleep, as individuals vary in their need for sleep. Insomnia may be classified as transient (lasting from a single night to a few weeks), intermittent, or chronic (occurring most nights and lasting a month or more).
In the study, the students with insomnia who were given relaxation therapy received three sessions, in which they were taught techniques for relaxing 16 muscle groups over a 20-minute period. The students were asked to practice the technique at home twice a day, including at bedtime. All the participating students were asked to keep sleep diaries during the two-week study.
While the students who used the relaxation technique reported small to moderate improvements in sleep quality and duration, there was no corresponding improvement in their functioning during the day, even though they did say they felt less sleepy during their waking hours.
"It could be the length of treatment was too short," Means says. Other studies have shown increases in quality of sleep after five to eight weeks of relaxation practices. This study lasted only two weeks.
Means believes that insomniacs who continued to practice relaxation after the study ended could very well see greater improvements later on. "As they become more proficient with the technique, I suspect their daytime functioning ultimately will improve," she says.