NORMAL
BM
Defecation
(make a BM, pooping, take a shit, drop the kids off at the
pool, do a number two, take a dump, etc.)
So
what happens during a bowel movement?
The
small and large intestines are muscular tubes. Normally,
these tubes contract in different ways to both mix the digesting
material and to slowly force the contents down the gut towards
the anus. About four times a day, a mass movement
forces the stool through the colon and towards the rectum.
When you eat a meal, food traveling through your upper gut
causes muscle to contract throughout your gut, and stool
from your colon is pushed into the rectum. This is called
the GASTROCOLIC reflex. This is why your morning coffee
can trigger you to need to move your bowels. This is also
why babies poop after they eat. The reason why you
don't poop after every meal is because you have learned
to control when and where you pass stool as you were growing
up.
Defecation,
or the act of passing stool, is partially voluntary and
partially involuntary. In other words, you can control
some parts of it, but not others!
When
stool enters the rectum, the rectum expands. This causes
a nerve reflex, which relaxes the internal sphincter of
the ANUS, and gives you the urge to move your bowels.
At this point you tighten your external sphincters until
you can find a toilet or other appropriate place to evacuate
your bowels. When you are ready to make a BM, you
take the position (sitting or crouching) and consciously
relax your external sphincters. The muscles of your pelvic
floor (levator ani - L) will also relax, thus allowing the
stool in your rectum to pass through to your anus.
Muscular contractions and gravity help push the stool through
your anus, and out.
How
often should I be moving my bowels?
There
are no set rules as to how often is normal. Though
the majority of people move their bowels once a day, this
varies considerably depending on your diet, activity, illness,
and many other factors. Once a day is a general rule-of-thumb,
although some "normal" people may have a bowel movement
only once in 2 or even 3 days. Sometimes people can
have more than one BM a day.
What
does a normal bowel movement look like?
A
normal bowel movement should be some shade of brown, should
be soft but still formed, and should be roughly the size
and shape of sausage links, although this can vary with
the softness of the stool. Your stool takes the shape of
your colon. Foods and vitamins you eat can affect how your
stool looks and smells, but so can diseases discussed in
the following section. Normal bowel movements DO NOT contain
blood, and are not black or tarry.
