Sleeping is not just necessary for relaxation. Even while we sleep, our bodies are constantly moving and important activities such as recovery of the muscles and release of gasses are happening as brain waves frequently change. Only when such processes go smoothly can we maintain our health and well-being.
1) The mouth and eyes become dry.
Saliva is secreted usually during waking hours especially when consuming food, while saliva secretion diminishes dramatically during sleep. For this reason, people may wake up in the morning and experience a dry mouth and sore throat. Moreover, tear production halts while sleeping, so your eyes may feel dry and stiff when you wake up.
2) The eyeballs move.
While other organs of the body are in rest mode during the time of sleep, the eyeball continues to move. There are four stages of sleep: Non-REM (NREM) sleep (Stages 1, 2 & 3) and REM sleep. While in REM, also known as rapid eye movement sleep, eye movements are, as it would appear by the name, rapid as your eyes move from side to side. Not only do your eyeballs rapidly move, but brain waves are also more active than in Stages 2 & 3 of sleep.
3) Digestion slows down and muscles are formed.
While we are in regular sleep, the digestive system goes into rest mode, slowing gastric emptying. REM sleep is typically associated with faster gastric emptying. Getting enough sleep helps the muscles recover and grow on their own. Moreover, while we are in deep sleep, muscles torn through exercise recover leading to growth.
4) Gas is released.
While you sleep, the anal sphincter, which is a group of muscles located at the end of the rectum that surrounds the anus and allows for the release of stool, relaxes. Therefore, intestinal gas is easily released out of the body. If the gas is not released efficiently, it will inevitably lead to abdominal distention.
Getting enough sleep every night is important because important activities and processes are undergone, such as recovery of the muscles and release of gas, all occurring while you sleep. Therefore, sleeping 8 hours each night is highly recommended in order to stay healthy.