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In today’s busy and fast paced world, sleep is considered a luxury.  It seems to me that most adults and probably many children are sleep deprived.  Only by becoming a sleep consultant did I begin to realize that I in fact am sleep deprived.  I generally get about 6.5- 7 hours of sleep a night.  I have always felt that anything more was really unnecessary and indulgent.  I’m a busy mom with a career -why in the world would I expect to get more than my standard 6.5-7 hours?

 

Well, since becoming a sleep consultant I have learned a great deal and I would like to share those lessons with you.  I will begin by explaining the two types of sleep and the stages involved in each type.

 

Non-REM (Rapid Eye Movement) is the first type of sleep and has 4 stages.  (Some studies will put stage 3 and 4 together.) 

 

Stage 1:  Transition to sleep.   It lasts about 5 minutes and during this time muscle activity slows down, eyes move slowly under the lids and you are easily awakened. This is also a time when you might experience what is called a myoclonic jerk (startled) or the sense that you are falling.

 

Stage 2:  Light sleep.  This stage lasts from 10-25 minutes.  Heart rate and body temperature go down.  Eyes stop moving.

 

Stage 3: Transitioning to deep sleep as slow brain waves known as “delta” waves begin to emerge.

 

Stage 4:  Deep sleep.  You cannot be easily awakened and if you do wake you will feel groggy and disoriented.  Your brain waves have slowed down considerably and your blood flow is directed towards your muscles in order to restore your physical energy.  You may dream during this stage but the dreams will be disconnected, less vivid and less memorable than during REM sleep.

 

REM (Rapid Eye Movement) Sleep:

 

This is known as dream sleep. It takes place about 70-90 minutes after falling asleep.  Your eyes move rapidly and your heart rate and blood pressure increase.  Your muscles are paralyzed.  (If you ever have a frightening dream and you want to get away from whatever is threatening you, this explains why you can’t!)  The first cycle of REM sleep may last for a short period of time, but with each cycle the length of time will increase and can last up to an hour as sleep progresses.  REM sleep is important for mood and memory.

 

Every stage of sleep is important because your body needs each in order to fully restore itself.   You will usually cycle through these stages 4-6 times a night in a total of 90 minutes.  These cycles however do not go in order.  You will begin with stages 1,2,3,4 and then back to 3 and 2 before you go to REM sleep. Once REM is over you will return to stage 2.  Deep sleep takes place in the earlier part of the night, while REM and stage 2 in the later part.  This can explain why you may wake at 3 in the morning yet not at 1.

 

When we talk about sleep deprivation we are talking about a lack of deep sleep. Deep sleep is essential for the body to repair itself, for boosting of the immune system and overall general maintenance which keeps us healthy.

 

The average adult spends 50% of sleep in stage 2 (light sleep), 20% in REM and 30% in the other stages.

 

So how much is enough sleep?  Adults should get between 7.5 to 9 hours of sleep a night.  What are some of the things you can do to make sure you are getting the correct amount for optimal health and alertness?

 

• avoid alcohol, caffeine and nicotine and heavy meals close to bed time.
• make your sleeping environment dark, cool and quiet.
• avoid the use of computers and cell phones before going to bed and while in bed as these have the effect of decreasing melatonin   (the sleep hormone) in your body.
• go to bed earlier at night or get up later in the morning.

 

If you are experiencing memory or mood issues, try to increase your amount of sleep in the morning.  The early hours of the morning are when most of REM sleep takes place.

 

Above all, try to be consistent about when you go to bed, and if on weekends or holidays you are able to sleep a bit later to make up for a sleep debt, by all means do so!