The term circadian rhythm refers to the 24 hour clock, and is often used in humans to refer to the sleep and wake cycle.
Plants and animals have circadian rhythms influenced by daylight and night – the heating and cooling cycle of the day. Our bodies also work to these circadian rhythms. Here are some examples:
- The lowest body temperature is in the early morning around 4 am.
- Blood pressure rises sharply at about 7 am and Melatonin drops sharply at about the same time.
- Morning is the time when a bowel movement is most likely.
- Mid-morning at around 10 am is when we are most alert.
- Highest body temperature is around early evening.
- The sleep hormone Melatonin rises sharply at about 9pm.
- The deepest sleep cycles are between midnight and 2 am.
Knowing how your circadian rhythm works can alter how you plan your day and manage sleep, to make the most of your body daily cycles.
- Getting up and being active during the first 2 hours of sunlight can help treat and prevent depression. Even being in the sun drinking your morning coffee or tea, or going for a walk, can set your circadian rhythm up for the next 24 hours.
- Eat breakfast because your body will use the most energy between mid-morning and the late afternoon. Not eating can cause your body to flick into starvation mode and cause a drop in concentration. Most people missing breakfast become hungry later in the day, and eating later in the evening disrupts sleep.
- Plan the most difficult tasks of the day for mid-morning. If you tackle the most challenging task in the morning, the rest of the day will go more smoothly!
- Do not eat a large or meal with lots of sugar in the evening because you don’t need the energy at this time!
- Avoid caffeine beyond your afternoon tea. Caffeine may confuse your body into thinking it is morning and get you going – which prevents sleep later at night.
- Darken the home after about 9pm. Try dim lighting. Don’t stay up at your computer in the hour before bed. Darkness helps the sleep hormone Melatonin to release.
- Do not argue, nor think about negative things after dinner. Your mind is likely to recycle your evening thoughts in your dreams all night. The hours before bed are best for reading material that you want to remember the next day, because the information will cycle in your memory during your REM sleep at night.
- Form a habit for going to bed. Avoid loud noises, wear comfortable clothes. Don’t go to bed cold. Sleep in a room that is the right temperature; not too cold and not too hot. Wear socks in winter to assist with regulating body temperature. Drink warm fluid rather than cold if you wake in the middle of the night. Cold water can drop your core temperature and cause you to stay awake in the early hours of the morning.
- Ensure you do not stay up past midnight or you will lose those few critical hours most important for sleep.
- Wake to the morning sun, or in winter try a bright light on a timer beside your bed. Waking to a bright light is more likely to stimulate your circadian rhythms into action!
While it seems logical that we respect our bodies and the naturally occurring day and night cycles (i.e. circadian rhythms), with modern technology we can stay up all night and sleep with our block out blinds all day. These modern conveniences are effective aids for shiftworkers, but not usual and even harmful if you want your body to function well.
Most people seeking the help of a psychologist will have sleep issues as one of their symptoms. Following these easy steps can save you a lot of grief and ensure your body functions in the way it was meant to!
If you still struggle with sleep, especially with nightmares, then visiting for a consultation to discuss may be helpful. Depression is another common mental health disorder that can occur due to poor sleep and those who have lost their wake and sleep cycles. Your local sleep centre can provide a report and do a sleep study if you are really concerned and this can be obtained through a referral from your GP. Please bring that report to your initial consultation if you are seeing me about primarily a sleep problem.
Author: Vivian Jarrett, B Psych (hons), AMAPS, MAICD.
To book Vivian please call 1800 877 924 or book online.