Zeitgebers Defined

External Timekeepers that Impact Alertness

Zeitgebers Overview

Zeitgeber are your body's timekeeper. They are cues given by the environment that reset the circadian rhythm. These cues literally impact the expression of our genes. The science of this process is called chronobiology. 

Examples of the key zeitgebers in humans are environmental cues like sunlight, exercise, and eating. When you do these activities and how much you do them impacts your circadian rhythm and energy levels throughout the day. Temperature and the even social interactions can also create environmental cues that tell your body when to be alert. These external cues reset the internal body clock, also known as your circadian rhythm. Naturally occurring sunlight is the strongest zeitgeber because of its impact on hormones like melatonin. Even when our eyes are closed, photoreceptors in the eye can detect sunlight. These photoreceptors respond to sunlight by inhibiting melatonin. Due to the fact that we have become indoor creatures, people are often out of touch with their circadian rhythm. This happens when you do not entrench your zeitgebers within your daily schedule.


Circadian Entrenchment Solutions

Try to do the following things at a similar time every day:

• Sunlight in the morning when you wake up
• Similar bedtimes and wake times
• Eat at consistent times in the day and not too close to night
• Exercise at the same time every day
• Stimulate yourself with social interactions at the same time every day


Circadian Optimizer

The chart at the top of the Today screen in the Sleespace app is your circadian optimizer. This chart gives you insights on the best times to do different activities like sleep and exercise. Learn about your circadian optimizer