Podcast: Play in new window | Download
Listen to the audio version at the bottom of the page or watch here.
A circadian rhythm is a roughly 24-hour cycle in physiology and behavior that repeats daily. These rhythms are endogenous, as they are generated by a biological clock, and they tend to have near-24-hour periods. They are found in plants, animals, fungi, and cyanobacteria.
The circadian rhythm is a natural process that helps organisms to anticipate and prepare for regular changes in their environment. For example, plants open their leaves during the day and close them at night, and animals are more active during the day and sleep at night.
The circadian rhythm is controlled by a master clock in the brain, called the suprachiasmatic nucleus (SCN). The SCN receives input from the eyes, which allow it to track the day-night cycle. The SCN then sends signals to other parts of the body, which coordinate the body’s circadian rhythms.
Circadian rhythms are important for maintaining health and well-being. When the circadian rhythm is out of sync with the environment, it can lead to problems such as jet lag, insomnia, and seasonal affective disorder.
There are a number of things you can do to help keep your circadian rhythm in sync. These include:
- Getting regular exposure to sunlight. Sunlight helps to regulate the SCN and keep your circadian rhythm on track.
- Going to bed and waking up at the same time each day, even on weekends. This helps to keep your body’s internal clock in sync with the 24-hour day.
- Avoiding caffeine and alcohol. Caffeine and alcohol can disrupt sleep and make it harder to fall asleep at night.
- Creating a relaxing bedtime routine. A relaxing bedtime routine can help you to wind down and fall asleep more easily.
An infradian rhythm is a biological rhythm that has a period longer than 24 hours. The most well-known example of an infradian rhythm is the menstrual cycle, which lasts for about 28 days. Other examples include seasonal affective disorder, which can occur during the winter months, and hibernation, which some animals do during the winter.
Infradian rhythms are controlled by the body’s internal clock, which is located in the hypothalamus. The hypothalamus is a small region of the brain that is responsible for many important functions, including regulating body temperature, sleep, and appetite.
The body’s internal clock is influenced by a number of factors, including light, food, and exercise. When these factors are consistent, the body’s internal clock keeps a regular rhythm. However, when these factors are disrupted, the body’s internal clock can become out of sync. This can lead to problems such as jet lag, insomnia, and seasonal affective disorder.
There are a number of things you can do to help regulate your body’s internal clock. These include:
- Getting regular exposure to sunlight. Sunlight helps to regulate the body’s production of melatonin, a hormone that helps to regulate sleep.
- Eating a healthy diet. A healthy diet can help to keep your body’s metabolism running smoothly.
- Getting enough exercise. Exercise helps to promote the production of endorphins, which have mood-boosting effects.
- Avoiding caffeine and alcohol. Caffeine and alcohol can disrupt the body’s sleep-wake cycle.
- Creating a relaxing bedtime routine. A relaxing bedtime routine can help you to wind down and fall asleep more easily.