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Which of the following statements correctly describes the amount of recovery sleep required to repay an accumulated sleep debt? The amount of sleep required to make up a deficit..
  • A
    is roughly half the number of hours of sleep missed.
  • B
    is at least twice the number of hours of sleep missed.
  • C
    is slightly greater than the number of hours of sleep missed.
  • D
    equals the number of hours of sleep missed.


The sleep/wake cycle can be thought of as a credit and debit system. In this system the individual is given two points for every hour spent asleep and has one point deducted for every hour spent awake. This is only a rough measure, as individuals vary considerably in the amount of sleep they require. The maximum credit available is 16 points. You cannot store credit points above 16 in anticipation of a long period awake.

The fewer points you have the readier you are to sleep. Normally the person will sleep when he/she has little or no credit and will sleep for about 8 hours, followed by a wakeful period of about sixteen hours when the sleep credit will be exhausted.

  • Hours Slept x 2 = Hours of Sleep Credit

Note: We believe there are 2 different questions out there, one referring to the hours of sleep missed and the other one which refers to the hours being awake.
1 h of sleep = 2 h awake
If one is 4 h awake, he/she will need 2 h of sleep to balance.
(Sleep hours = half the time of being awake)

If one has lost 4 h of sleep, he/she will need 4 h of sleep to balance.
(Sleep hours missed = sleep hours needed)

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