Fooling Your Internal Clock

We changed to daylight savings time this weekend and I thought that this would be an interesting time to try an experiment with your internal clock. Making the change on April 1, which we celebrate as April Fool's Day in the USA, also seems appropriate. April Fool's Day is a day for playing harmless tricks, so we will try to learn something from the trick Daylight Savings Time plays on your internal clock.

You will need:

• yourself
• a notepad or computer to keep a journal
• a clock

While you may not have thought about it, we do have our own, built-in clocks. This internal clock may not be as accurate as the one on the wall (and mine is definitely a bit slow), but it is surprising how well your body keeps track of time. To investigate this, I want you to keep a journal for the coming week. Pay attention to the things that you usually do every day at the same time. For instance, getting up. Whether you are getting up for school or work, you probably get up at the same time on most days. If you are in the USA or other parts of the northern hemisphere that observes daylight savings time, you have probably just set your clock back one hour. That means that if you usually get up at 6:00 AM, your body will think that you are getting up at 5:00 AM instead. Each morning when you get up, notice if you feel more sleepy than usual. Keep track of how many days it takes for you to get your internal clock reset to your new schedule.

You can do the same thing with going to bed. Notice if you get sleepy at an earlier time than you usually do. Pay attention to when you get hungry. You might even keep track of things like remembering your favorite TV show. Do you think of it just as it is going off? If other family members are willing to keep a journal as well, you can compare to see how well each one adapts to the change.

It really is amazing how well your internal clock works. It varies a lot from person to person, but many people will wake up close to the proper time, even if the alarm does not go off. As I child, I would wake up automatically at 6:30 AM every Saturday morning to watch Superman on TV. Of course that did not work for school days, when I would sleep as long as I could.

Your pets have internal clocks too. Our dog Calley knows that her supper time is 6:00 PM and is accurate to within minutes, letting me know that it is time to stop what I am doing and feed her. Pay attention to your dog, cat, fish, etc., and you will probably find that they know when it is feeding time, even before you start to prepare the food. This should be a good week to observe that as well. In fact, our dog Calley is letting me know very strongly that it is time for me to feed her, so I had better get this out and start feeding. Have a good week.

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