From fatigue to readiness: Rethinking watchkeeping schedules for submariner performance
- 24-h anchored watch systems outperform non-24-h rotations — they support longer, more consolidated sleep and reduce circadian misalignment.
- Extended off-watch periods are optimal — they provide restorative rest, improve alertness, and are preferred by crews.
- One schedule does not fit all missions — short, high-tempo operations may tolerate compressed patterns, while long patrols require circadian-friendly designs.
- Circadian-informed lighting is a powerful countermeasure — blue-enriched light during watch boosts alertness, and dim/blue-depleted light before rest improves sleep.
