Sleep–It’s Body Repair Time Series: Part 5 (Body’s Internal Sleep Clock) - ICN INDIA

Sleep–It’s Body Repair Time Series: Part 5 (Body’s Internal Sleep Clock)

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By: Dr. Sanjay Kumar Agarwal, Sr. Associate Editor, ICN Group

(In the last article, we knew about the different sleep cycles during the night. Today, we will know about the body’s internal sleep clock.)

Body’s Internal Sleep Clock

Have you ever wondered, how some members of your family wake up at the same time every day without using alarm clock? The answer is simple. This is because of body’s internal sleep clock. Your internal sleep clock provides you clues and automatically works on those clues to tell you when to take rest, when to sleep, how deep to sleep, and how long to sleep. 

Sleep clock and body temperature 

The first important element of your sleep clock is your body temperature. Your inner sleep clock is aligned with the rhythm of your body temperature, which keeps on changing during different parts of the day. With increase in body temperature, we tend to feel energetic and with drop in body temperature, we start feeling lethargic. Normally, the body temperature gradually starts rising in the early morning hours and starts decreasing from afternoon. It again begins to increase during evening; and at night, it again starts decreasing, reaching its lowest point early morning, say at about 4 AM. If you understand this cycle of body temperature, it would not be difficult for you to understand, why your body needs afternoon nap and why after taking a small afternoon nap, you feel energised and become more productive for rest of your evening. Change in body temperature rhythms is also a primary reason behind ‘Jet Lag’ because when you travel across different time zones, your body may be in different time zones and different climatic zones, but your body temperature rhythm still tends to follow its regular pattern. 

Sleep clock and Melatonin

The second important element of your sleep clock is your melatonin hormone level, and your exposure to natural sunlight. Have you ever thought why do we normally sleep at night only? Is there any message from God in this regard? No. I think it is mainly because of two reasons:-

First reason is obvious that during the day, there is sunlight and it soothes to work in the natural light and it will be difficult to work during the night, therefore, daytime happened to be the first choice to do the work and night is the first choice to take the rest. 

Second reason is that there is an inbuilt system in our body that controls our sleep patterns on the basis of light & darkness. Our body produces one hormone, called ‘Melatonin’, which is mainly responsible for making us ready to sleep. 

Melatonin is a hormone, controlled by the exposure to light, specially sunlight. Your brain secretes more melatonin in the evening when there is low sunlight and less during the day when it is bright light and you need to be alert. It is produced in high quantity in the darkness. It also differentiates between natural sunlight and artificial light. Higher the exposure to natural sunlight, it will delay the drop in bodily temperature and you will stay energised for longer period of time. If your exposure to natural sunlight is less, your body temperature will drop speedily and melatonin production will increase and you will start feeling drowsy & tired and your body will start wanting sleep. The bright lights of TV or computer screen may result in lesser production of melatonin, thus it will make for you harder to sleep. Maximum exposure to sunlight during the day is the key, whether at office or at home. During night, before sleep, try low wattage bulbs.

To slightly raise the body temperature during the evening and delaying fall in temperature, you can start playing some physical game or do some physical activity during the late evening hours. If you do some physical activity in the evening or play some game, like table tennis or badminton in the evening (but remember, before dinner, as doing any heavy physical activity after dinner may carry harmful effects), it will slower the fall in body temperature, and you will remain energised for longer period. This will also result in dramatic fall in body temperature in the night which will make you enjoy more restful sleep during the night. 

Don’t change your wake up time by 1-2 hours at one go

Normally, your body temperature developed over a period of time tends to remain the same even if you change your wake up time. Suppose, by now, you are habitual of waking up at 7 AM and suddenly you want to start waking up at 5 AM, you will wake up at your alarm’s call, but your body temperature will be low, as over a period of time, your body has become habitual of waking up at 7 and your body’s temperature starts rising only after 7. This is the main reason why sudden change in wake up time is not advisable. 

If you want to change your wake up time by two hours, do it gradually by 15 minutes at a time. This will benefit you in two manners. One, your body temperature cycle will start adjusting to your changed habits and will adapt to the new wake up time in 15-20 days. Second, your bedtime in the night will also start adjusting by 15 minutes at a time and you will not experience fatigue due to sudden early rising. 

This is the main reason that most of the people, who take a wow to rise early, are not able to continue this for more than a week. They don’t understand the internal sleep mechanism of the body and start complaining that early rising is painful and they cannot follow this.  

Now with this understanding, you must be aware that you don’t have to decide that you are going to reduce your sleeping time by one hour or so. Let your body decide it for you.

Your sleep clock will gradually adapt to your sleep cycles and you will start rising early than ever before. This difference in sleep time may vary from person to person but for most of the people, this will be in the range of 1 to 2 hours, depending upon when stage 5 of your sleep cycle is finished and your internal urge to urinate becomes more urgent for you than entering in another sleep cycle. 

[In the next article, we will know about benefits of waking up early. So, stay tuned to improve your sleep patterns.]

Dr. Sanjay Kumar Agarwal, Creator & trademark holder of the concept G.O.P.T.A.®  is an Author, Growth Accelerator Coach, GOPTA NLP Trainer and Strategic Interventionist. ( He is recipient of Honorary Doctorate of Excellence (Management) by prestigious Young Scientist University, California, USA. He is creator of ‘Ethical Mind Influence’ program for growth & success ( ). He is Founder of ‘International GOPTA NLP Academy’ and is popularly known among his fans & followers across the globe as ‘Time and Goal Guru’.

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