Tick Tock, Our Internal Clock

We’ve all felt it: It’s two in the afternoon and you’re dragging.

If you’re making coffee in the middle of the workday in a weak attempt to stay on task, you can thank your body’s circadian rhythm. (Why our body thinks we need to sleep during the middle of the day, though, is still a mystery…)

Each of us has an individual sleep schedule kept on track by our body’s internal clock, which is controlled by our circadian rhythm. Your circadian rhythm relates to the physical, mental and behavioral changes that follow a 24-hour cycle and respond to light and darkness in the environment. They regulate your periods of sleepiness throughout the day, which dip and rise at different times. The sleepiness we experience during these dips may be less or more intense depending on the amount of sleep we get at night. The average adult’s strongest sleep drive usually occurs between 2am and 4am and 1pm and 3pm, although variations can occur depending on whether you’re a “morning bird” or a “night owl.”

Healthy Sleep

Sleep Disruptions

A disruption in our circadian rhythm, such as jet lag or a bout of insomnia, makes us feel sleepy and unable to complete tasks efficiently. In order to adjust to these disruptions, our body is forced to stray from its normal pattern of how it reacts to time and light cues. Jet lag is the most well-known internal clock disruption, but these symptoms can occur during our everyday lives as well.

Having an inconsistent sleep schedule can disrupt your circadian rhythm and, as a result, may cause sleeping disorders such as delayed sleep phase syndrome (DSPS) and advanced sleep phase syndrome (ASPD). These disorders are not permanent, however, and can be fixed by maintaining a healthy sleep pattern.

It’s important to find a sleep-wake rhythm that works with your schedule—and to stick to it. Even on the weekends, you should try not to deviate from your sleep schedule more than one or two hours. The transition back into a healthy sleep schedule needs to happen gradually, so try shifting the time you go to sleep and wake up five to 10 minutes a day until you reach your desired time frame. (Parents, keep this in mind come end of summer when it’s time to get the kiddos ready to go back to school!)

Napping can interfere with your ability to fall asleep at night, so avoid taking naps even if you feel tired. Even one day of napping on a lazy Sunday can disrupt all the progress you’ve made. During the day, try to get at least 15 minutes of sunlight so your body understands when you need to be awake. If you work indoors, step outside for a quick break to take in some sunshine. The most important thing for healthy sleep is consistency in your schedule (so keep your late-night antics to a minimum, you party animal).