Your body’s internal circadian biological clock is responsible for regulating your sleep and wake periods throughout the day. This clock, also referred to as the circadian rhythm, is a 24-hour cycle thatreleases “sleep” and “wake” hormones. This clock is controlled by an area in your brain called the Superchiasmatic Nucleus (SCN) which is located in the hypothalamus. The optic nerves in your eyes pick up light and dark signals and send messages to your brain. Light signals tell your brain and body when it is daytime and time to be awake. This awake signal increases body temperature and releases the hormone cortisol, while also reducing melatonin levels. Melatonin is a hormone that helps you sleep and is released when your brain receives dark signals from the optic nerves.
A natural 24-hour sleep-wake cycle mimics the rise and setting of the sun. Before artificial light was invented, humans would go to bed when it was dark and wake when the sun rose. In modern day this is not as common and not always possible, but our body’s internal clock still runs on a 24-hour cycle. Whether your circadian rhythm mimics this natural cycle, or varies, it is important to maintain a routine as much as possible. A change or disruption to your sleep routine and your 24-hour internal clock may cause tiredness, brain fog, and other issues especially if you aren’t getting the recommended 7-9 hours of sleep each night.
Go to sleep and wake-up at the same time each day, even on the weekends. Although you may look forward to sleeping in, if you reset your circadian rhythm and get 7-9 hours of sleep per night, you won’t crave this extra sleep as your 24-hour clock will be on-time.
Depending on the time of year and when you go to sleep, it may still be light outside when you’re ready to hit the pillow. This light can make it difficult for your body to know when it is time to sleep. It can be helpful to keep the lighting inside your house similar to the natural light outside to mimic a natural sleep cycle. If you sleep during the day - dim the lights inside, use window coverings, and sleep in a dark room by using blackout curtains, blinds, or a sleep mask. The dark signals picked up by your optic nerve will tell your brain to release the hormone melatonin which will help you fall and stay asleep.
Ideally you should use natural light to wake-up. If you cannot wake-up by sunlight you can try a light-emitting alarm clock. Typically, these clocks gradually increase light for about 30 minutes before the alarm. This light triggers your optic nerve to signal your brain to decrease melatonin levels and increase cortisol so that you wake-up. Another option is to go outside after you wake-up or sit by a window for about 30 minutes to get some sunlight and signal your body that it is morning. If it is dark when you wake-up, you can try a light therapy lamp that mimics sunlight for the same effect (speak to your doctor about using a light therapy lamp).
There are many strategies that can help to improve your sleep quality and by resetting your clock you will have a good foundation for a restful sleep.
Other strategies to improve sleep quality include:
- Limit caffeine intake late in your day
- Avoid mentally stimulating activities before bed – ex: competitive games, studying, etc.
- Avoid alcohol intake before bed as it may help you get to sleep faster, but it can disrupt your sleep cycles leading to poor quality sleep
- Avoid looking at screens for 1-2 hours before bed as the blue light emitted can interfere with your sleep signals – this includes phones, tablets, TV’s, etc.
- Avoid exercising in the 3 hours before sleep, if possible
- Don’t eat or snack too close to your bedtime
- Keep your bedroom dark and cool
- Try relaxation and breathing exercises before bed