Recovering after a run of night shifts
Updated October 12, 2026 · with an example to try
In one study of shift workers, one day off after a run of nights wasn't enough to recover, two usually were, and long shifts in long runs needed three. In a study of nurses, alertness on days off was lowest on the first one. So a day shift 24 hours after your last night comes before you've recovered, even if you feel fine after one good sleep.
See a day shift after three nights
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An end time at or before the start means the shift ends the next day.
- Shifts
- Assumed sleep
- Predicted alertness
- Below 7: likely sleepy
| Shift | Lowest alertness | At the end | Sleep in the 24 h before | Awake at start |
|---|---|---|---|---|
| Mon, Nov 2 19:00 to 07:00 | 5.0 at 05:45, below 7 | 5.1 at 07:00 | 8 h | 12 h |
| Tue, Nov 3 19:00 to 07:00 | 4.2 at 05:45, below 7 | 4.3 at 07:00 | 4.5 h | 6.5 h |
| Wed, Nov 4 19:00 to 07:00 | 3.8 at 05:30, below 7 | 3.9 at 07:00 | 4.5 h | 6.5 h |
| Fri, Nov 6 07:00 to 19:00Less than 2 days after 3 nights in a row: in the research, one day off wasn't enough to recover (why). | 9.3 at 07:00 | 10.4 at 19:00 | 11.5 h | 1 h |
An estimate from a model that combines time awake, the body clock and assumed sleep: not a measurement of how you slept or feel, and naps aren't modeled. Higher is more alert; below 7, people are likely sleepy. "At the end" is the drive home. The model counts one good sleep as enough, so it can't show the slower recovery marked in amber.
Three 12-hour nights, then a day shift 24 hours after the last one ends. The curve shows the day shift as alert, because the model counts one good sleep as enough; the people in the studies below took longer, so the shift is marked. How the model works.
What the research found
- In one study, one day of recovery after nights wasn't enough, two days usually were, and long shifts in long runs needed three (Åkerstedt and colleagues, 2000).
- Among 61 nurses followed for 28 days, alertness was lowest on the first rest day after a night shift, and rest days after nights were worse than rest days after day shifts (Totterdell and colleagues, 1995).
- In a lab study of 159 adults, one long recovery night, even 10 hours in bed, didn't undo 5 nights of short sleep (Banks and colleagues, 2010).
Planning the switch back to days
- Ask for 2 days off, at least 48 hours, between your last night and a day shift, and 3 after a night float block or another long run of long shifts.
- If you moonlight or work at two sites, count those shifts too: a day shift elsewhere 24 hours after your nights is still a short recovery.
- The free two-calendar check puts the calendars of two or three jobs together and lists every day or evening shift less than 48 hours after a run of 2 or more nights.
Common questions
- How many days off do I need after a run of nights?
- Two, in the research, and three after long runs of long shifts, such as a night float block.
- Why am I so tired on my first day off?
- You start it short of sleep, with your body clock still set to nights. In a study of 61 nurses, alertness on days off was lowest on the first one.
Chart your own shifts over time.
Capillary Health makes scheduling software for hospitals and clinics. The free checks keep nothing; a free account is different. It saves your work calendar's shifts and charts your hours, nights and rest between shifts over time. No one in your department or hospital sees them (who can see what).