Alarm clocks are never pleasant. But they become even more obnoxious when they go off an hour earlier, as they will this coming Sunday when Germany implements daylight savings time.

For some that's not a problem, but teenagers in particular seem to struggle more than others. Scientists agree that teens need about three times as long to adjust to the new time as adults.

The urge to turn around and stay in bed or the ability to get up effortlessly is mainly determined by our genes. But during adolescence hormones take over and interfere with our sleep rhythm, turning most students into night owls who cannot get to sleep at night and have trouble getting up in the morning.

"The sleep duration and the different sleep phases change with aging," Dr. Thomas Penzel, senior researcher at the Berliner Interdisciplinary Center for Sleep Medicine, told DW. "Very small children like babies need up to 16 hours of sleep a day and maybe only eight hours when they are 15, and then after puberty there is again a lengthening of sleep of roughly one hour."

But for most teenagers and young adults, going to bed early to make up for this increased need for sleep is not really an option. Not only does their changed sleep rhythm keep them awake, but sleep is not very high on their agenda if alternatives like socializing, TV and computers come into play. Part-time jobs, hobbies and even studying disrupt sleeping patterns even more.

Catching up on the weekend

To the astonishment of many parents and teachers, teenagers do well with a schedule of sleep deprivation during the week and going out on the weekends if they can then sleep all day Saturday and Sunday.

"Catching up on sleep after staying up all night actually works," explained Dr. Heidi Danker-Hopfe, head of the Competence Center of Sleep Medicine at the Charité Berlin. "The next night we will have a bit of a recovery sleep, which makes our sleep more efficient. But overall this cannot cover for a chronic sleep deprivation during the night."

It's the total sleep duration that matters in recovering properly. This sleep need varies from person to person, but is usually between six and nine hours. During those hours our bodies go through different sleep phases that are repeated throughout the night. Doctors talk about light sleep, deep sleep and REM sleep (rapid eye movement sleep).

"Each phase is important in its own way," said Dr. Thomas Penzel. "Deep sleep is really important for the immune system, for the growth hormone so that we grow as we age, and the REM sleep is very important for learning and memory."

This suggests that placing a book under the pillow and "absorbing" the information while sleeping is not as far fetched as it sounds. The key is not just to sleep on the book but read it just before going to sleep. Then learning while sleeping can actually work, especially when getting enough uninterrupted sleep.

Dangerous behavior

But sleepiness and poor concentration are not the only problems teenagers have when not getting enough sleep, said Dr. Heidi Danker-Hopfe. "Other consequences of poor sleep during the night are increased risk-taking behavior, so some may be more likely to use a drug for example or [demonstrate] risk-taking behavior and we also know that there is a negative effect on mood."

Despite the research showing how important sleep is, students won't stop going out and start putting their noses in their books instead. But maybe timing it a bit better and making sure to catch up on sleep are some things teenagers can do to make it through those years.

Also not eating or drinking too much before going to bed and not watching TV or staring at computer screens all night can improve sleep as well. And then dealing with the cutting sound of the alarm clock in the morning might not be so hard after all.