How much sleep should you be getting a night and why?

There's no magical number of hours required. We don't need any set of amount of sleep - and depends on many factors BUT it's all down to genes and whether we feel fresh and alert during the day.

Healthy sleep is characterized by specific sleep sequence of stages.During sleep, while our bodies rest and recharge, we cycle between two main types of sleep: rapid eye movement sleep (REM) and non-rapid eye movement sleep (NREM). These two types of sleep usually take place over four non-REM stages and one REM stage throughout the night.

Non-rapid eye movement sleep (NREM)

During NREM sleep, our bodies repair and regenerate tissue, build bone and muscle, and are thought to recharge our immune systems. It is devided into 4 stages

NREM : STAGE ONE
During this stage, our sleep is quite light and we can be awakened fairly easily. Our eye movement and muscle activity also slow down.

NREM : STAGE TWO
This is also a stage of light sleep, but our eye movement stops and our brain waves slow down. Our heart rate also begins to slow and our body temperature decreases. This is when our bodies prepare to move into deep sleep.

NREM: STAGE THREE & FOUR

known as "deep (slow-wave) sleep," the most restful kind of sleep. During these stages, extremely slow brain waves, called delta waves, are produced and there is no eye movement or muscle activity.

REM Sleep

REM is defined by brief spurts of increased activity in the brain. REM sleep is considered the dreaming stage of sleep. It typically occurs about 70 to 90 minutes after we fall asleep. Our breathing becomes shallow and irregular, our muscles relax, our eyes begin to move rapidly, our heart rate increases, and our blood pressure rises. During this stage we often experience vivid dreams.

The sleep cycle usually begins with a period of about 80 minutes of NREM sleep followed by about 10 minutes of REM sleep. This 90-minute cycle is repeated four to six times each night. If the sequence is interrupted (for example, by external noise or a sleep disorder), the quality of our sleep suffers.

So although the amount of sleep you get is very important, your stages of sleep determine how well-rested you'll be when you awake.

Getting more NREM sleep
Deep sleep is perhaps the most vital stage.It is the first stage that the brain attempts to recover when sleep deprived, and the strongest effects of sleep deprivation are from inadequate deep sleep.To maximize your deep sleep make sure your sleep environment is as comfortable as possible and minimize outside noise. Or do whatever to make sure that you get some time of uninterrupted sleep. Don’t be afraid to ask for help.

Getting more REM sleep
REM sleep, or dream sleep, is essential to our minds for processing and consolidating emotions, memories and stress. It helps boost your mood during the day. To get more REM sleep there is ONE simple way is to try to sleep a little more in the morning. As your sleep cycles through the night, it starts with longer periods of deep sleep. By the morning, the REM sleep stage is longer. Try sleeping an extra half hour to hour and see if your mood improves.

Prof Horne, the author of Sleepfaring says: "The test of insufficient sleep is whether you are sleepy in the day or if you remain alert through most of the day". In another place he says also "A journey through the science of sleep, says the idea that Victorians got lots of sleep and had a better work-life balance is a myth.

If you sleep for eight hours a night go to work and find yourself lolling and drooling on the keyboard, you aren't getting enough. If you're sleeping five hours and running the country, you probably are getting enough.

The US National Sleep Foundation suggests seven to nine hours a night is advisable for adults, and a survey it conducted in 2002 suggested three-quarters of Americans had problems sleeping and a third were so sleepy during the day their activities were affected. Infants tend to need the most sleep, averaging about 16 hours a day, while teenagers need about 9 hours.