Likewise, those who prefer to go to bed earlier may not do well with social or cultural activities that are programmed later in the evening. People who have a later chronotype may suffer from social jetlag and feel permanently tired if they need to wake up early for work or school. When a person’s natural chronotype comes into conflict with the demands of their schedule, this is termed social jetlag. Scientists consider it very difficult or impossible to purposely change your chronotype, though it may shift throughout the course of your life. For this reason, night owls have historically faced more difficulty adapting to typical work schedules. If most adults need between seven and nine hours of sleep a night, this is usually much easier to accomplish for an early bird than for a night owl, who has trouble falling asleep before 1 am. Conversely, an early bird may wake up bright and chipper for their 7 am shift, but then start to feel sleepy already in the late afternoon.Ĭhronotype does not influence total sleep time. Thus, a natural night owl may be able to wake up at 7 am every day for work, but they may not be productive until later in the day. However, while circadian rhythm can be “ trained” by adhering to a strict schedule, the underlying chronotype exists on a more permanent basis. Sleep chronotype is closely related to circadian rhythm, which controls the day-to-day sleep-wake cycle and releases melatonin in response to environmental cues such as light and temperature. It is responsible for the fact that you feel more alert at certain periods of the day and sleepier at others. In addition to regulating sleep and wake times, chronotype has an influence on appetite, exercise, and core body temperature. Chronotype is the natural inclination of your body to sleep at a certain time, or what most people understand as being an early bird versus a night owl.

Sleep chart by age and wake up time