Among Australian high school students involved in a 4-week healthy lifestyle class, researchers report the "surprising" finding that 95 percent of the subjects had at least one type of sleep problem.

Still, "It seems the Sunday morning sleep-in is something they don't want to give up," Dr. Michael Gradisar, at Flinders University in Adelaide, South Australia, told Reuters Health.

The 81 students commonly reported taking a long time to fall asleep, not getting enough sleep, or having inconsistent bedtimes.

During the 4-week intervention, students, who were 16 years old on average and 33 percent male, tended to lessen the discrepancy between their school-day and weekend rise times by about 30 minutes, the investigators report in the journal Sleep.

"But this change was small and short-lived," Gradisar said.

At the intervention school, 41 students participated in four 50-minute classes designed to increase their knowledge about healthy lifestyle behaviors, and specifically about healthy sleep patterns.

Another 40 students, attending a different school, received standard health education, but completed the same questionnaires as the intervention students.

At the start of the study, 53 percent of the students reported insufficient school-night sleep (less than 8 hours). Nearly 78 percent reported more than a 2-hour discrepancy between their school-day and weekend rise times.

Another 60 percent said they required more than 30 minutes to fall asleep at night, and 35 percent reported excessive daytime sleepiness.

After completing the intervention, almost 42 percent of the students said they valued sleep more, and now considered sleep as important as diet and exercise in maintaining a healthy lifestyle.

We were pleased to hear the teenagers honestly report they wanted to get more sleep on school nights, Gradisar said. However, since they were not necessarily prepared to regularize their sleep patterns to obtain more sleep, Gradisar's team plans to assess how a revised, sleep-focused intervention might motivate students to improve their general sleep health.