ABSTRACT
The work of Dr Nathaniel Kleitman, the father of sleep science, was instrumental in helping us understand internal body rhythms. One of the ways that pilots frequently encounter circadian disruptions is through the rapid crossing of multiple time zones. Whenever traveling from one time zone to another, the body's rhythms and the time-giving cues supplied by the outside world become out of sync and the syndrome of 'jet lag' arises. Unlike jet lag where environmental cues can help to resynchronize the body's clock with the new time zone. Shift lag tends to persist because the normal timing cues remain in opposition to the body's new work/rest schedule. Shift lag is hard to overcome because shift workers are constantly fighting an opposite environmental light/dark cycle. No wonder routinely flying international routes can produce a state of chronic jet lag that compromises the ability to stay awake and alert in the cockpit!.
