Health Updates

Resetting Your Sleep Clock

Does the following description sound at all familiar? You're sitting in class. It's close to the end of the period or to dismissal time, and you're having trouble stifling that yawn. It's not as though you didn't get any sleep the previous night. So what's the problem?

Scientists working in a new field called chronobiology have come up with a possible explanation. Chronobiology is the study of effects of time on living things. This science is based on the assumption that our bodies run on internal clocks. Unlike the clock on the wall, these inner clocks run on their own time. This is why people experience "jet lag" when they travel across several time zones.

Time Out

What chronobiologists have discovered is that teens' internal clocks are set differently from other people's. As a rule, adults and young children beginning feeling tired a few hours after sunset. Teens, on the other hand, run on clocks whose "drowsy" setting does not occur until several hours later. If you have a bedtime of 9 or 10 o'clock and don't feel sleepy, this may be why.

In the best of all worlds, you'd be able to stay up later and rise later the next morning. In the real world, things aren't like that. School starts early. This means you need to be up and out in time for school–even if you were up late the night before. The resulting problem is known as sleep deprivation. This problem can lead to other problems, most of them serious. They include:

• Difficulties concentrating and learning. One study showed that students who are sleep-deprived lose 30 percent of what they learned the previous day.
• Motor vehicle collisions. A recent study in North Carolina revealed that 55 percent of crashes in which the driver fell asleep involved people 25 years old or younger.
• Behavioral problems. A tendency to fight a lot or to act up in confrontations with parents can sometimes be traced to a lack of sleep.

Early to Bed, Early to Rise?

Okay, so the old saying about getting to bed and getting up early doesn't necessarily apply to teens. What can be done to fix the problem?

One answer, being tried by some high schools, is a later start time. The entire school day begins and ends later. This trend, however, is far from widespread. What can you personally do if you are suffering from too little sleep?

• Avoid doing strenuous exercise at bedtime. The belief that exercise will tire you out is a myth. If anything, the extra blood pumping through your veins will keep you awake longer and later.
• Steer clear of stress—producing activities as bedtime approaches. If you're having problems with a friend, don't call at 9 p.m. to straighten things out. On the other hand, don't let causes of stress in your life build up. You don't want to lie awake at night thinking about your problems. Instead take constructive action during the day.
• Skip that afternoon nap. Many teens take a short snooze when they get home from school. There is nothing unhealthy about napping, but remember it may make it harder for you to get to sleep at bedtime. Also, sleep specialists believe that the best sleep is sleep that extends over larger blocks of time.

Just the Facts

1. What is a chronobiologist?
2. Define sleep deprivation. Name three problems that can be caused by sleep deprivation.
3. What are two habits you should avoid close to bedtime if you have problems getting to sleep at night? Why should you avoid them?

Beyond the Facts

4. Explain in your own words why many teens are not sleepy at their assigned bedtimes.
5. What effect do you think staying up late on Friday and Saturday nights has on a teen's sleeping patterns? Explain your reaction.

Applying the Facts

Another way to beat sleep problems is by trying to reset your body clock. Try the following experiment for four school days. Keep a log of your results.

Day One: Set your alarm clock to go off 15 minutes earlier than usual. Get up and perform your normal morning activities. Use the extra time to enjoy a good breakfast, eating slowly. Try getting into bed 15 minutes earlier than usual.

Day Two: Set your alarm clock to go off 30 minutes earlier than usual. Use the extra time to plan your day or chat pleasantly with family members. Go to bed one half hour earlier than normal.

Day Three: Set your alarm clock to go off 45 minutes earlier than usual. Use the extra time to complete a homework assignment you may have left unfinished the night before. Again, retire to bed 45 minutes earlier than you normally would.

Day Four: Set your alarm clock for the normal time. Notice at what time that night you begin to feel sleepy.

Share your log and results with classmates.