An executive who has worked on short sleep for months may feel that the routine is manageable. Feeling familiar with the routine does not show that performance is unchanged.
In Van Dongen and colleagues' sleep-restriction experiment, performance deficits accumulated while subjective sleepiness did not reflect the full change. The findings are more specific than the common claim that every short night is equivalent to a fixed number of hours awake.
Look at the repeated pattern
Record the sleep opportunity allowed by the working week. Include the late calls, early travel and unfinished preparation that move bedtime. These arrangements are often easier to identify than a general feeling of fatigue.
Do not use a good morning or a successful meeting to conclude that the pattern has no cost. Equally, do not attribute every difficult decision to sleep. Examine preparation, information and the work itself.
Change the schedule that creates the deficit
Pick a recurring source of lost sleep that can be changed. A call may be moved, a trip shortened or a briefing prepared by someone else. Agree on what happens during genuinely exceptional periods so that the exception does not become the default.
Consumer sleep trackers can help describe trends, but their estimates should not be treated as a diagnosis. Persistent insomnia, breathing interruptions or daytime sleepiness call for qualified assessment.
Review whether the changed arrangement gives people a realistic opportunity to sleep. Advice about recovery has limited value if the organization continues to require work at both ends of the night.
