Health experts at one of the world’s leading institutions have explained how understanding one thing about sleep can transform how you feel when you wake up. Scientists at Harvard Medical School in the US said that, of course, sleep was essential for helping the body to recover, repair itself and function at its best.
Further, they said understanding sleep cycles could “help you improve your sleep hygiene and wake up feeling truly refreshed”. They said that most of us think of sleep as simply not being awake.
But they said it wasn’t that straightforward, explaining that “scientists divide sleep into two major types: REM (rapid eye movement) sleep or dreaming sleep, and non-REM or quiet sleep. Surprisingly, they are as different from each other as each one is from waking — yet both may be important for energy”.
They said: “Non-REM sleep involves three stages: light sleep, deeper sleep, and deep sleep. Sleep specialists believe that the last stage, known as deep sleep or slow-wave sleep, is the main time when your body renews and repairs itself. This stage of sleep appears to be the one that plays the greatest role in energy, enhancing your ability to make ATP, the body’s energy molecule.
“In deep sleep, blood flow is directed less toward your brain, which cools measurably. At the beginning of this stage, the pituitary gland releases a pulse of growth hormone that stimulates tissue growth and muscle repair. Researchers have also detected increased blood levels of substances that activate your immune system, raising the possibility that deep sleep helps prepare the body to defend itself against infection.”
They explained that someone whose deep sleep was restricted would wake up feeling less refreshed than a person who got adequate deep sleep. When a sleep-deprived person gets some sleep, they “will pass quickly through the lighter sleep stages into the deeper stages and spend a greater proportion of time there, suggesting that deep sleep fills an essential role in a person’s optimal functioning”.
The expert added: “REM sleep helps restore your mind, perhaps in part by helping clear out irrelevant information. Studies of students’ ability to solve a complex puzzle involving abstract shapes suggest that the brain processes information overnight. Students who got a good night’s sleep after seeing the puzzle fared much better at solving it compared to those asked to solve the puzzle immediately.
“Other studies, from Harvard Medical School and elsewhere, have found that REM sleep facilitates learning and memory. People who were tested on how well they had learned a new task improved their scores after a night’s sleep. If they were prevented from having REM sleep, the improvements were lost.”
More information can be found via Harvard Medical School’s Special Health Report, Boosting Your Energy.