Category: Circadian Rhythm Sleep Cycles

Many people want to explain circadian rhythms so they can better understand why they feel alert at certain times and sleepy at others. Circadian rhythms are internal biological processes that repeat roughly every 24 hours and shape sleep, mood, appetite, and many bodily functions. This article explains how these rhythms work, how they connect to […]

An internal clock governs many of the daily processes that keep us alert, rested, and healthy. Often referred to as the internal body clock, this timing system coordinates sleep, hormone release, body temperature, and metabolism. Understanding how the internal clock works — what scientists call the circadian rhythm — helps explain why you feel sleepy […]

Sleep is influenced by two connected systems: the body’s internal clock, which helps determine when you feel awake or sleepy, and the repeating stages of sleep, which shape what happens after you fall asleep. Understanding both can make it easier to identify why sleep feels restorative on some nights and disrupted on others. What is […]