SLEEP
... or do you frequently wake up during the middle of the night and struggle to go back to sleep? ... If your answer is yes to any one of these questions, you could have a sleep debt that is affecting you in ways you dont even realize. ... It is important to understand the reasons humans need sleep; how much is needed; the factors and affects of lack of sleep and practices for good shut eye. It may sound trivial to some but since 1/3 of our life is spent on sleep, where the average human sleeps about 8 hours a day (equivalent to 122 days a year), it seems to be worth noting. Sleep is more than just beauty rest for the body; it helps restore and rejuvenate the brain and organ systems so that they function properly. The emotional and mental benefits of sleep are also significant. ... Chronic lack of sleep is hazardous to a persons health, performance, memory and mood. While studies indicate that most people can decrease the amount of their sleep by two or more hours without immediate harmful side effects, there are some essential elements to sleep. Briefly, this is how we sleep: After shutting our eyes, we enter into a deep sleep, also known as stage 4 or slow wave sleep. ... This stage changes on a 90 minute cycle with Rapid Eye Movement - which is sleep characterised by a high level of activity and dreaming. ... There are also stages of non REM sleep, where heart rate and respiration slow down and blood pressure declines. ... REM sleep (which makes up 20% of our sleep time) is what we cant do without - disrupting it continuously can kill us, but only after stages of reduced learning ability, memory loss and hallucinations.