Internal Sleep Clock

Our body tries to conform its sleep-wake cycle (called circadian rhythm) to the 24-hour cycle of the planet's rotation. However, different people may have different rhythms that are not equal to 24 hours.

You are more likely to experience sleep problems if your internal sleep-wake cycle is strong but does not match the 24-hour day cycle.

If you have insomnia, you need to maintain a regular, daily rhythm, even if it's a struggle.

Many shift workers suffer from insomnia. Usually, it takes at least two weeks for a body to adjust to the new schedule. By then, their shift rotates, and the internal clock gets reset again. The circadian rhythm cycle has no chance to get re-establish, and shift workers spend their lives in a perpetual kind of jet lag.

Adjusting Your Sleep Clock

It is important to realize that the length of the sleep-wake rhythm changes during our lifetime. Sleep research recommends these different approaches for younger and older people when adjusting their internal clock to the world's 24-hour schedule:

For the young, the best way is to always get up in the morning at the same time. It doesn't matter that that time is, but it should be a consistent time.
For elderly, the best way is go to bed at consistent time.

Obviously, there is no clear age borderline when to use which of these two approaches. It just depends on the individual. If one does not work, try another. In my opinion, the first approach (waking up at regular times) has a greate chance of helping with insomnia. - The reason is that you can set the alarm on certain time to wake you up, but you can't force yourself to sleep.

Try to determine if your insomnia reveals itself periodically, by keeping a sleep log. For example, you typically may have few weeks of good sleep, alternating with a few weeks of bad sleep. If this is the case, you may have a circadian rhythm disorder. It may be that your sleep-awake cycle is either shorter or longer than 24 hours, which periodically comes in and out of "sync" with the 24-hour day cycle.

Phototherapy

The light has a strong effect on the body's internal clock. Try treating a fast, slow, or out-of-sync sleep cycle clock by using phototherapy.

If you have difficulties falling asleep in the evening, go outside and get bright light in the morning.
If you wake up too early, get out in the evening for some bright light and go to bed later.

The light has to be sufficiently strong for the phototherapy to work. Artificial light has to be at least 10,000 LUX. However, bright outdoor light has the best effect. Do not wear sunglasses (see more on sunglasses later).

You need to experiment with the length of the light exposure. Typically, it could be between 30 minutes and one hour.

Try phototherapy for at least two or three weeks, and see if your sleep improves. If your sleep-wake clock has adjusted, you can reduce the amount of the light exposure and maintain your clock synchronized at lower light levels. If phototherapy has no effect after two weeks of two hours of daily light exposure, your insomnia problem is likely to be somewhere else.

Insufficient amount of light during the day (dark office and home environment) can impair the establishment of the strong sleep-wake cycle and contribute to your insomnia problems. Get high intensity light during long indoor hours.

Even the amount of ordinary household light can have an effect on some people: you might be helped with dimmer light in hours before bedtime, sleeping in a very dark room, and letting the sunlight stream into your bedroom in the morning.

Effects of Sunglasses

Sunglasses can block from 20% to 80% of the sunlight entering our eyes. Additionally, most people who wear sunglasses wear them when they don't even need to.

As light plays an important role in maintaining body's internal clock and healthy sleep, wearing sunglasses makes it harder to maintain the proper sleep-wake cycle.

Many insomniacs receive a boost of better sleep and energy throughout the day simply by wearing their sunglasses less often, or eliminating the use of them completely.

However, sunlight can be damaging to our eyes in certain circumstances. Therefore, try to minimize your use of sunglasses, and use your common sense as to when they may be appropriate.