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Adolescents' Unique Biological Sleep Needs Often Conflict with High School Start Times

August 19, 1999, WASHINGTON, DC /PRNewswire/

Teenagers returning to school for the academic year need to take specific steps now to tune their unique sleep needs with the demands of the school year, urges the National Sleep Foundation (NSF).

With puberty comes a delay in the timing of teens' internal body clocks, or circadian clocks, which regulate sleepiness and wakefulness. Teenagers aren't able to fall asleep until at least 11 p.m. or later, and awaken later in the day. Typically, they also need more sleep than their younger siblings and their parents -- about 9 hours and 15 minutes. Shifting to an early morning school schedule is difficult for adolescents after summer vacation, when most teens go to bed very late and "sleep in," a pattern that more closely resembles their internal clock than the school year schedule.

"Because of their unique sleep needs, teenagers' brains are not ready to be alert until long after the typical high school day has already begun," explains Richard Gelula, NSF Executive Director. "Also, researchers have found that even adolescents who get an adequate amount of sleep tend to be drowsy during the mid-morning and alert in mid-afternoon because of their internal clock."