Circadian rhythm -- your internal body clock

  • Published
  • By Senior Airman Sigmund A. Tanseco
  • 71st Medical Operations Group, Aerospace Physiology Flight
VANCE AIR FORCE BASE, Okla. --  A circadian rhythm is not the latest dance craze or newest genre of music. It is your internal body clock. More literally, it means "about a day," which is roughly a 23- to 26-hour cycle. 

This cycle involves various body processes that control sleep-wake cycles and directly affects alertness and performance. If your circadian rhythm is disrupted, you may start to experience chronic fatigue; which will negatively impact your performance. 

The two most common circadian rhythm problems are sleep-cycle disruptions and circadian rhythm desynchronization. 

Sleep-cycle disruptions occur when you change your normal rest and wake cycles. This happens when you either wake up earlier or stay up later than usual. If you cut your sleep over a long period of time, you shorten the part of your sleep cycle that is vital to mental alertness. 

You can experience mental fatigue, resulting in a reduced attention span, concentration, and increased reaction time, and perceptual errors. You should maintain a consistent sleep time, even on the weekends or days you have off. 

You can attempt to minimize or eliminate sleep cycle disruptions by adjusting the time you go to sleep. Eventually, your body will become accustomed to the new sleep times. 

Circadian rhythm desynchronization is more commonly known as "jet lag." This occurs when you cross one or more time zones. For every time zone you cross, it can take up to two weeks to completely adapt. 

Traveling from north to south in the same time zone does not result in jet lag, and traveling westbound through time zones is easier on the body than traveling eastbound. 

Desynchronization leads to problems such as decreased mental agility, impaired judgment and decision-making skills, decreased communication and problem-solving skills, and increased irritability. 

To combat desynchronization, you should slowly adapt to the new time zone by eating and sleeping according to their time zone. Trying to force your routine to conform to the local time will have an adverse effect on your circadian cycle. 

It is important to stabilize your circadian rhythm. If you can't avoid disrupting your circadian rhythm, take the appropriate steps to adapt and bring it back to normal as soon as possible. That way, you can rest assured that your "body clock" keeps on ticking.