Using Controlled Daylight Exposure and Sleep Timing in the Prevention of Shift Lag during Night Operations.

摘要

In the Army aviation community, a significant component of combat and training missions is night operations. Mission requirements often necessitate an initial shift from daytime to nighttime duty hours within 24 to 48 hours. Rapid shifts from daytime to nighttime work, and nighttime to daytime sleep usually result in loss of sleep, degradation of alertness, increased fatigue, and reduced work effectiveness. These symptoms are referred to as 'shift-lag' because the body's physiological adjustment lags behind the rapid shift to the new work schedule. Research on shiftwork provides a variety of approaches to avoid the deterioration of performance and health of shiftworkers. Shift-lag prevention plans may consider the speed of shiftwork rotation, the duration of each shift, age of workers, physical strength associated with work demands, diet, timing of sleep, and in some cases, the use of drugs to induce sleep and attempt to resynchronize the body's internal biological clock. However, the use of controlled timing of daylight exposure and of sleep schedules are of overriding importance. In the Army aviation context, consequences of shifts to nocturnal work schedules without the implementation of a shift-lag prevention plan have been recently documented. This work reviews the mechanism of biological timing in humans, the role of environmental lighting, and specifically identifies methods of preventing sleep loss and fatigue during the transition from daytime to nighttime duty hours. Shift-lag countermeasures, Circadian rhythms, Coping strategies, Shiftwork, Night operations.