Like most animals on earth, humans have a built-in biological clock, which is a roughly attuned to the 24-hour day-night cycle of the Earth. However, sleeping patterns vary considerably depending on genetics, age and personal habits.
Most people sleep about eight hours a night, but bed times vary. There are 'morning people' and 'night people' who function better at different times during the day. Some people function better early in the morning, others late at night.
Many teenagers stay up late at night and may only average 5 or 6 hours of sleep. Various medical authorities are worried about how this lack of sleep is affecting the health of teenagers and their attention at school. See: Teenage Obesity and Teen Weight Gain Linked to Late Sleeping Patterns.
Sleep researchers have shown that with adequate training and persistence most people can reset their biological clocks and even 'night people' can become 'morning people'.
This article shows how this can be done.
Recent research has shown that the human biological clock is much closer to 24 hours than previously thought.
Early research suggested that the activity rhythm and body temperature rhythm averaged about 25 hours in adults, and tended to get shorter with age. This led to the concept of 'drift', with the 25 hour period being out of alignment with the 24 hour cycle of the earth.
The idea was that if we missed the dawn, bright-light trigger that resets the internal clock back to align with the earth cycle we would drift out of alignment. This could lead to insomnia, problems waking up, jet lag issues and general problems of staying alert during the day.
However, recent research has shown that the human circadian pacemaker averages 24.18 hours. This cycle applies to people of all ages.
The rotation of the Earth imposes a 24-hour period on the lives of humans and other living things. The human biological clock is composed of a tiny group of nerve cells (called the 'suprachiasmtic nucleus') embedded deeply in the brain and linked to the optic nerves of the eyes.
A closer match between the earth's 24 hour rotation has led to new strategies for dealing with sleep problems and wake-up times involving night work, jet lag issues, or just not being able to go to sleep and wake up on time after the week-end sleep-in sessions.
Accepting the near-24-hour period means that old concept of 'drift' has to be re-thought. The concept was that we drift to wake-up times that are much later on weekends, because we fail to reset our internal clocks as we do on week-days. Our internal clocks were said to 'drift' out of alignment reverting to the 25 hour period if there were no reset signals (such as bright lights at dawn).
The new research shows that we are not drifting but we are simply pushing ourselves to wake-up later with our continuous exposure to electric lights and TV / Computer screens from sunset to bedtime. This behavior sends a series of reset signal to our biological clocks that become very confused.
These clock issues can be solved by going to bed earlier on weekends and using bright light to reset our clocks.
► To begin the reset process, set your alarm to wake you up 20 minutes earlier each day over a week or more. If you usually get up at 8 AM, but really need to get up at 6 AM., set the alarm for 20 minutes earlier each day.
► When you wake up make sure you get out of bed straight and don't linger in bed. Turn on a bright light - better still use a timer instead of an alarm, so that the bright light is turned on automatically and you have to get up to turn it off yourself with light.
► Try Bright Light Therapy which works by resetting the biological clock see article. If the sun is already up, take a short stroll outside or open the curtains to let the light into the room. If you wake before sun rise, keep yourself in a well-lit room or work close to a bright lamp that will act to reset your internal clock.
► In theory, with this approach you should get sleepy about 20 minutes earlier each night. You can help the process by minimizing bright light exposure from televisions or computers as you near bedtime. Also avoid the usual things that keep you awake such as coffee after 5 PM, caffeinated soft drinks, sugar-laden snacks, chocolate, etc.
► Wake up at your revised time each morning by setting an alarm. This may be hard at first, especially if you don't adjust the time you go to bed, but over two or three weeks it works.
It may take a couple of days for you to get used to the altered time schedule.