Sleep loss leads to profound performance decrements. Yet many individuals believe they adapt to chronic sleep loss or that recovery requires only a single extended sleep episode...
Despite recurrent acute and substantial chronic sleep loss, 10-hour sleep opportunities consistently restored vigilance task performance during the first several hours of wakefulness. However, chronic sleep loss markedly increased the rate of deterioration in performance across wakefulness, particularly during the circadian “night.” Thus, extended wake during the circadian night reveals the cumulative detrimental effects of chronic sleep loss on performance, with potential adverse health and safety consequences.
In other words a 10 hour session of “make up” sleep is not restorative if sleep deprivation is chronic, defined as getting 7 or fewer hours sleep per night over time. Researchers don't know how long it takes to recover from chronic sleep deprivation other than to say that 3 days doesn't seem to be enough.
I work a 7 day on 7 day off schedule and this rings true to me. I progressively accumulate sleep debt during the on week. It seems to take most of the off week to recover. But it was even worse back in the days of working every week with rotating night call---like having jet lag once a week.
H/T to Clinical Cases and Images.