Wrist Activity Monitoring in Air Crew Members: A Method for Analyzing Sleep Quality Following Transmeridian and North-South Flights

Home base recordings of motor activity during bedtime, and of subjective sleep parameters, were obtained from air crew members before and after the following routes with multiple flight segments: (1) south-north (SN) across 1 time zone; (2) west-east (WE) across 17 time zones; (3) east-west (EW) across 7 time zones. For the EW route, recordings were also obtained during layover. Only after return from the EW route was bedtime motor activity (measured by a wrist-worn ambulatory monitor) enhanced, was the percentage of bedtime immobility periods reduced, and were frequency and duration of self-assessed waking after sleep onset increased. The subjects rated their sleep as less quiet and felt less rested than during baseline. The various parameters gradually reverted toward baseline during the first 4 days at home. Although sleep showed only minor impairments during the EW route, the subjective jet-lag score was high during layover and after return to home base. Ambulatory activity monitoring is a useful method for assessing sleep quality after long-haul flights.