[[Special:MyLanguage/Biphasic|Biphasic]] sleep is often used for the recovery as well. Having two blocks of sleep, it is possible to use an alarm for one of them, without restrictions for the second one.
二相睡眠也是被常用的回复类型。因为这种时程有两个睡眠段落，可以对其中一个中使用闹钟，而对第二个不设限制。
