Fullpower-AI’s ongoing analysis of its 250+ million-night dataset has identified consistent weekly cycles embedded within the previously documented seasonal heart rate patterns. This week’s infographic zooms into the weekly structure, using continuous nocturnal heart rate data captured non-invasively by the Sleeptracker-AI platform.

The seasonal signal holds: nocturnal heart rate is lower in summer and higher in winter — a pattern Sleeptracker-AI’s machine learning models identified independently, which is also corroborated by an independent study conducted in Japan.

Within each season, a reliable weekly rhythm is also present. Heart rate is lowest early in the week, rises progressively toward the weekend, then recovers — repeating consistently week after week. The weekly periodicity is driven by the same behavioral factors identified previously: bedtime discipline, diet, and alcohol consumption loosening toward the weekend and tightening again at the start of the work week. The regularity of this cycle across the full dataset makes it one of the more structurally stable patterns in the data.