Can you 'bank' sleep in advance?

Banking sleep will protect you for one all-nighter, but no more than that.


Asked by: Clare Hastings, by email

To a limited extent, yes. A 1991 study at Wright State University in Dayton, Ohio found that after an ordinary night's sleep, subjects could take an extra nap in the afternoon and then work through the night with greater alertness that a control group who didn't nap. The study also found that performance was proportional to the length of the nap – but the effect doesn't last.

After a second consecutive night without sleep, all of the subjects performed equally badly, regardless of how much sleep they had initially. It may be that all of us are normally slightly sleep-deprived and one really good night's sleep will bring us back up to 100%, but that the 'tank' isn't big enough to buffer us against more than one all-nighter.

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