ANCSLEEP BLOG

What Is the Ultradian Rhythm?

The ultradian rhythm is a natural biological cycle that repeats multiple times throughout the day, typically every 90 to 120 minutes. Unlike the circadian rhythm, which follows a 24-hour cycle, ultradian rhythms regulate shorter bursts of energy, focus, and rest.

These cycles influence how alert, productive, and mentally fatigued you feel throughout the day—even if you don’t notice them consciously.