Reap the benefits by listening to your body clock
The party season has come to an abrupt end and you now face back to work, tired. You may have made every effort to be moderate in all things. Hopefully you did not drink and drive. You may have avoided making a fool of yourself at the karaoke in front of your workmates, and the unwanted attentions of your boss were rebuffed.
But most agree that Christmas Day is one to celebrate. And for some New Year's Eve has now been added to the list. Even with sensible eating and drinking, late nights are impossible to avoid at this time of year.
So on January 1 you are likely to feel sluggish and rundown in spite of your sobriety, although this is mild compared to how you felt in your wilder years. It seems difficult to accept that despite your moderation, things are still not right. One of the reasons for this is because your circadian rhythms are disturbed.
The circadian rhythm is the 24-hour physiological cycle or clock that is present in humans. This means that certain activities of our body are programmed to vary over a 24-hour period, and when this pattern is disturbed, we feel unwell.
It is these circadian rhythms that cause people to feel more energetic early in the morning or drowsy in the afternoon. Late-night partying is one cause. Those who are kept awake, such as mothers and fathers with babies, and people on night call-out, such as hospital doctors, will often describe a dramatic dip in mood during those dark hours.
Insomniacs who wake during sleep, at 4am to 5am, will often feel that the world is terrible, a place of sorrow and gloom, of fear and terror; yet this is a perspective that shifts seismically during daylight hours to optimism and joy.
It is the surge in the depressant hormone cortisol during this period that is largely responsible for these mood dips. And this may explain why some episodes of self-harm occur most often during the hours of darkness.
Other bodily functions are also affected by circadian rhythms, including pain thresholds, which are higher in the afternoon. So, if you are considering having a tooth filled, you may need less pain relief if you visit your dentist in the afternoon. Similarly if you want to exercise, you will be able to do so with greater ease in the afternoon.
On the other hand, deaths peak in the morning due to increases in clotting properties of blood at that time of day. Interestingly, it's not only humans that have such rhythms but also plants, animals and even bacteria and fungi.
It is tempting to try and change this internal clock to a longer one, because if our routine could be determined by a 36-hour cycle, we could potentially achieve much more, both personally, with our families, friends and professionally. However, it seems that the programming of this clock is fairly rigidly set at 24 hours.
Some experimental researchers tried to extend this to 25.5 hours in the last decade, but without much success.
The timekeeper is located in the base of our brain. Called the suprachiasmatic nuclei, these receive signals from outside influences, known as zeitgebers of which light, social contact and sleep are the most obvious.
If you have partied into Christmas and beyond, remember that your body, even in the absence of alcohol and rich food, will try to set its 24-hour clock each night.
If you go to bed after midnight on a regular basis, you will suffer the equivalent of jet-lag, as your timekeeper cells misread the actual time. You will feel exhausted in the morning and napping during the day may make things worse as will having a lie-in or hitting the snooze button.
The solution is to restore your regular, predictable and boring time schedule.
Your granny may be old and unhip, but she was also wise and learned when she told you that when sleeping is concerned, one hour before 12 is worth three after.
Health & Living