He said Mr. Glenn would awaken and go back to sleep during the middle of his sleep period, something the former astronaut said he did not remember doing.
Longer naps can cause sleep inertia, or a period of grogginess and reduced performance caused by waking in the middle of deep sleep.
And right now we're in the middle of a sleep deprivation crisis, with devastating effects on our health, our job performance, our relationships, and our happiness.
Set an alarm clock for the middle of your sleep cycle.
I sleep in my middle-of-the-range sleeping bag, wearing all of my clothes – four pairs of trousers, three fleeces, two hats and waterproofs.
"People just went running off into the woods, going for walks to the middle of nowhere, sleeping out in the fields".
Before our young narrator knows what's happening, she's in the middle of nowhere, sleeping in a dank, windowless dormitory full of persecuted elders -- a group of "undesirable human weeds," which in this case are some of the most important scholars in China.
Often time after being woken up early or in the middle of a deep sleep, it can be difficult to get back to sleep.
For me, the chief asset was in being woken up by a vibration at my wrist at the end of a deep sleep cycle (it will wait, you see, instead of catching you in the middle of a deep sleep, which would leave you lethargic) rather than by my alarm clock.
In the middle of a sound sleep a few weeks ago, John W. Mack, the president of the Los Angeles Urban League, was awakened by a sound he had hoped had vanished from the night here: the unmistakable rattle of gunfire echoing through the streets.
