# Time Management Researcher

> Browse 1 item in Time Management Researcher.

## Items

- [Nathaniel Kleitman - Ultradian Rhythm Discovery](https://timetrack.works/ar/items/nathaniel-kleitman-ultradian-rhythm-discovery) — Sleep researcher who discovered in the 1950s that the human body moves through 90-120 minute cycles (ultradian rhythms) throughout day and night, foundational for understanding natural work-rest patterns.

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