Understanding Adolescent Sleep

Our sleep needs change as we age and during adolescence, teenage sleep undergoes a shift that often works against many expectations set forth by academic and social schedules. It is important to understand how these changes affect children during their middle school and high school years in order to best support their physical health and wellbeing, academic success and extracurricular participation from the arts to athletics to part time jobs.

The “afternoon crash” is well-documented: people of all ages may feel drowsy in the afternoon, experiencing an energy deficit that prompts some to take a nap and others to look for a snack. Many people experience drowsiness at another set time, but they don’t notice it because they’re asleep: the second crash happens between 2-4 a.m., according to the National Sleep Foundation.

It is our circadian rhythm that is responsible for this — it is the force that regulates our internal clock and drives our sleep/wake cycle. The severity of the energy crash is heightened in people who don’t get enough sleep. By contrast, those who get adequate rest typically do not experience as much of a swing in energy levels. Circadian rhythms change with age, and that also affects energy levels — including in teenagers.

Read also: The Importance of our Circadian Rhythm.

Circadian rhythms change, as children who need significantly more sleep than adults age into adolescence. This change causes teenagers to become more alert in the evening, which makes it harder for them to fall asleep at night. Parents might notice their teenagers staying up later and finding it harder to wake up and start their day the next morning.

According to the American Academy of Sleep Medicine (AASM), children aged 6-12 need between 9 and 12 hours of sleep and teenagers aged 13-18 should get between 8 and 10 hours of sleep every night.  Not surprisingly, the wide spread sleep deprivation is not limited to adults – surveys show that the majority of American adolescents do not get enough sleep.  In fact, nearly 60% of middle school aged students and more than 70% of high school aged students do not get the recommended amount of sleep each night.

Shifts in Circadian Rhythm Shift Energy Levels

When teenagers start staying up later, they may have a difficult time getting sufficient sleep, depending on when they have to get up to get ready for school. Teens sleep an average of 9.25 hours but typically need at least 8 hours of sleep to function at peak levels (although this varies by individual). When sleep is disrupted, energy deficits can occur between 3-7 a.m. but can persist as late as 10 a.m.

Low energy levels can be a problem for teenagers year-round if they need to wake up early for work, athletics, or other activities. It is a significant issue during the school year since sleep deprivation affects the ability to focus and learn. Now consider that the average start time for U.S. high schools is 8 a.m., meaning teens have to wake up even earlier to get to school on time.

Recognizing that teens have a different circadian rhythm, the Seattle Public Schools changed start times across the district in 2016, shifting the opening bell from 7:50 a.m. to 8:45 a.m. University of Washington researchers studied the effects of the change and found that teens used the additional time to sleep in, with a median increase of 34 minutes of sleep per night. Research on the change also found that extra sleep measurably improved students’ academic performance.

In 2022, California became the first state to mandate later school start times.  With this new law, middle schools cannot start earlier than 8:00 AM and high schools cannot start earlier than 8:30 AM.  In fact, the American Academy of Pediatrics (AAP) recommends that middle and high school start at 8:30 AM or later to give students the opportunity to get adequate sleep which is critical for both their physical wellbeing and academic performance.

What Parents Can Do to Help Teenagers Get Enough Rest

So, what can parents do to make sure their teens get sufficient rest? Studies suggest maintaining a regular bedtime is key. A sleep study published in the Journal of Sleep Research found that teenagers perform better academically when they turn in between 10-11 p.m. Among teens participating in the study, those who kept to the same sleep schedule on weekends had the highest grades.

Read also: Why Worry about Sleep Deprivation Among Students

But grades aren’t the only or even the most important reason to make sure teens get sufficient sleep. Lack of sleep interferes with decision-making, leading to poor impulse control. Drowsiness has an impact on memory and the ability to concentrate, which can have safety implications, especially while driving. And sleep deprivation can affect health, leading to poor nutritional choices.  Youth are experiencing higher levels of mental health issues as a result of fatigue and poor sleep.

Parents who want to help their teenagers make better decisions about sleep might consider sharing information with their adolescents so they understand the science behind sleep recommendations. An overview geared toward teenagers, like the National Sleep Foundation’s Teens and Sleep page, can help start the conversation. Encouraging teens to go to bed around the same time every night is also a good idea.

Good habits start early, and getting adequate rest is important for lifelong health and wellness.