What happens in sleep that cannot happen during meditation?
Sleep can be divided into five phases, or stages. The first four
are numbered 1-4, and the last one is REM. Natural sleep, one that
does not involve the use of drugs of any kind, has all five stages.
The stage four part of sleep is when your body repairs itself and
can only be reached through natural sleep. Also, your muscles
become paralyzed during REM sleep.
The main thing is in sleep one becomes unaware. Thoughts happen,
dreams happen, images pass through the mind, but for the most part,
there is no awareness of these things.
When meditating, these things happen, but there is a witness, a
watcher on the hill: there is awareness of what is happening in the
body-mind.
Meditation is great for keeping calm during waking hours, but is
not a substitute for 7-8 hours of good natural sleep. Though
meditation may help someone calm their mind so they get a better
nights sleep, it is only natural sleep that has a deep delta sleep
as in stage four non-REM sleep.