Most drivers are not aware that an internal mechanism is secretly plotting to create problems for them at the wheel.
We all have this nasty creature living in our bodies and we all are affected by it.
Knowing of its existence and effects can make a big difference to our safety and that of those with whom we share the road.
This demon is our circadian rhythm — a patterns of activity that occurs on a 24-hour cycle. Circadian rhythms are important biological regulators that exist in virtually every living creature.
In humans and other animals, the internal circadian clock is in our brain and it regulates sleep and wake cycles, as well as body temperature, blood pressure, and the release of various hormones.
Circadian rhythms, like our sleep-wake cycle are generated by an internal clock synchronized to light-dark cycles in the environment, and other cues. Our internal circadian clock has been rewound every day by sunlight, since time began.
Don’t take this too lightly. Last year the Nobel Prize for medicine was awarded to a trio of men who have identified the molecular structures that control circadian rhythms.
Scientists are hard at work trying to determine what role circadian rhythm plays in everything from heart disease to obesity. What we do know is that circadian rhythm plays a vital role in driving. Each day we experience profound changes in both mental and physical condition as our body and brain alternate between periods of rest and activity — day and night for most of us.
These cycles are driven by our circadian rhythms — which commonly vary by as little as minutes per day. Studies conducted with volunteers have shown that even when deprived of light and other outside factors the circadian clock kept accurate time for several days.
Think of your circadian rhythm as a wave with peaks and valleys. At maximum amplitude we are most alert and at the peak of our functionality.
At the other extreme we are least alert and can hardly function. The trick is that our circadian rhythm operates on a 24-hour cycle — with two peaks and troughs per day — 12 hours apart.
During the lows we can easily become drowsy or fall asleep — here is the issue. For most of us the low points occur somewhere between two and four am and 2-4 p.m.
The latter is the problem. If you are behind the wheel at that time, there is a strong possibility, baring any outside influence, you can nod off or that your concentration will lapse dangerously.
If you are not already aware of your personal circadian rhythm, try to become so. Monitor your concentration — the problem will usually occur when driving alone on during periods of low traffic on high-speed roads where little driver input is required.
You may find your eyes closing briefly, your attention lapsing, or that you do not remember the last km or so of travel.
For example, if your circadian low occurs between 2:30 and 2:45 each day, it is not due to the usual after-lunch excuse. The problem is real, and serious.
People who do a lot of driving during the afternoon will likely be aware of this phenomenon — and adjust or allow for it even if they cannot name it.
The problem lies with infrequent drivers, those who on vacation, or for some other reason, take the wheel at this critical time.
With the sun beating down warming the interior it is awfully easy — and fatal — to succumb to the body’s internal clock.
Once you’ve identified your personal “low,” avoid driving at this critical time. Plan your lunch or a break around it.
And remember, just like a watch, our circadian rhythm must be reset to local time when travelling and during time changes each spring and fall.
