I have heard that supposedly when after you receive a massage you are
often told to drink lots of water (or fluids, I would guess) because
receiving a massage releases toxins and you need to flush them out of
your system. Frankly, this sounds like hippie stuff. Is there any
actual hard scientific evidence to support or refute this claim?  If
your answer is good, I?ll add a $10 tip.

Frankly, any time I see claims that something removes unnamed toxins
from the body, my pseudoscience skepticism is activated. I've gathered
some online info that I hope will help you to evaluate the "massage
myth."

"The ability of massage to remove muscle 'toxins' or lactic acid has
also been claimed to result in benefits to the healing of muscle
damage and DOMS [delayed onset muscle soreness]. It has been well
established that lactic acid does not cause muscle soreness sensation
and that lactic acid and 'toxins' have no influence on
exercise-induced muscle damage. Hence this suggestion can be dismissed
outright. In addition, human studies have demonstrated that massage
has no influence on post-exercise blood lactate clearance, while mild
exercise can significantly speed up its removal. Since, as previously
mentioned, massage has little influence on muscle blood flow, this
finding is not surprising. Several recent studies have also found
little consistent effect of massage on DOMS. One earlier study, albeit
with a limited subject pool, also found no effect of massage on
circulating levels of the potential analgesic hormone, b-endorphin."

IVIS: A Review of Human Massage Therapy
http://www.ivis.org/proceedings/AAEP/2000/302.pdf

"There's a statement, seemingly pervasive throughout massage education
and massage books, that unspecified toxins accumulate in the body, and
that these toxins can be flushed out by massage. I believe this is yet
another myth that continues to be passed on as misinformation to
massage students. This is not to dispute that there are very real
toxins that accumulate in the body, notably persistent organic
pollutants (POPs) in fatty tissues and heavy metals in skeletal
tissues. However, these toxins are too chemically bound to their
target tissues to be significantly liberated by the mechanical motions
of massage."

Massage Today: Flushing Out Myths
http://www.massagetoday.com/archives/2002/12/08.html

"To examine the effects of leg massage compared with passive recovery
on lactate clearance, muscular power output, and fatigue
characteristics after repeated high intensity cycling exercise, with
the conditions before the intervention controlled and standardised...

Conclusions: No measurable physiological effects of leg massage
compared with passive recovery were observed on recovery from high
intensity exercise, but the subsequent effect on fatigue index
warrants further investigation."

British Journal of Sports Medicine: Effects of leg massage on recovery
from high intensity cycling exercise
http://bjsm.bmjjournals.com/cgi/content/full/38/2/173

"This investigation highlights the comparison of blood lactate removal
during the period of recovery in which the subjects were required to
sit down as a passive rest period, followed by active recovery at 30%
VO(2)max and short term body massage, as the three modes of recovery
used.... Analysis of lactate values indicated no remarkable difference
between massage and a passive type of sitting recovery period. It was
observed that in short term massage recovery, more oxygen was consumed
as compared to a passive type of sitting recovery. It is concluded
from the study that the short term body massage is ineffective in
enhancing the lactate removal and that an active type of recovery is
the best modality for enhancing lactate removal after exercise."

PubMed Abstract: Comparative study of lactate removal in short term
massage of extremities, active recovery and a passive recovery period
after supramaximal exercise sessions
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8833711&dopt=Abstract

Some additional interesting reading:

Quackwatch: Massage Therapy: Riddled with Quackery
http://www.quackwatch.org/01QuackeryRelatedTopics/massage.html

Quackwatch: A Massage School Experience
http://www.quackwatch.org/01QuackeryRelatedTopics/massageschool.html

Ask Metafilter: Does massage release toxins?
http://ask.metafilter.com/mefi/22571

I am aware that massage has spiritual significance for many. I have
found no scientific studies that address the effects that spiritual
beliefs about massage may have on body chemistry. In posting the
information that I've gathered on this subject, I intend no disrespect
to those who practice massage and related therapies.

Staying well-hydrated is, of course, very important. But I have seen
no good evidence that there is any special reason for those who are
receiving massages to consume extra fluids (unless the massage also
involves heat treatments or active exercise that might cause
dehydration). There's no proof than any significant "flushing of
toxins" is achieved as a result of having one's muscles manipulated.
Indeed, although anecdotal endorsements and theories abound, there
isn't much hard evidence of any kind about massage:

"There are many theories about how massage may work, although none has
been scientifically proven. There is limited research in this area. It
is suggested that massage may have local effects on muscles and soft
tissues, reduce inflammation, soften or stretch scar tissue, reduce
the buildup of lactic acid in muscles, stimulate oxygenation of
tissues, break up adhesions, induce muscle fiber relaxation and
stimulate healing of connective tissues or damaged muscles. Other
proposed effects include immune system enhancement, reduction of blood
pressure, central nervous system relaxation and sedation,
parasympathetic stimulation, blockage of sensations from nerves that
sense pain (the "gate theory"), stimulation of blood and lymphatic
circulation, decreases in heart rate, increases in skin temperature,
endorphin release, alteration of hormones such as cortisol,
stimulation of substance P release, stimulation of somatostatin
release, sleep enhancement or removal of blood toxins. Practitioners
suggest that Swedish massage may assist the body in delivering
nutrients and removing waste products from various tissues.

There is little high-quality research of massage. Scientifically based
conclusions about the effectiveness of massage cannot be drawn at this
time for any health condition... Massage has been suggested for many
other uses, based on tradition or on scientific theories. However,
these uses have not been thoroughly studied in humans, and there is
limited scientific evidence about safety or effectiveness."

InteliHealth: Massage
http://www.intelihealth.com/IH/ihtIH/WSIHW000/8513/34968/365286.html?d=dmtContent

My Google search strategy:

Google Scholar: massage toxins
http://scholar.google.com/scholar?q=massage+toxins

Google Web Search: massage toxins
://www.google.com/search?hl=en&q=massage+toxins

I hope this is helpful! If anything is unclear or incomplete, please
request clarification; I'll be glad to offer further assistance before
you rate my answer.

Best regards,
pinkfreud

Just as I suspected!  Thanks for the great work.  You should get the
tip as promised.

Thank you very much for the five stars and the generous tip!

~pinkfreud

If you need citations for a class paper this would be a good way to go
about doing that. If you want some kind of personal proof try this, it
won't even cost you $20.

Don't drink water for a day or two, just a minimum ammount to get
through the day. Next do as many calf raises as are needed to ensure
you will be sore and tired for the next day or two. Get a friend to
massage out that sore calf you now have. Alternatively you can do this
yourself, just work on stretching the muscle back and forth, this is a
pretty intrinsic action and doesn't require much explanation. Note how
you feel the next day. Repeat this entire process a couple times, then
try a couple more times without having a massage. Also try a few times
while drinking plenty of water and having a massage. If the worked
calf feels considerbly worse one day following a massage while being
dehydrated in respect to being well hydrated that would support the
toxin (read lactic acid) hypothesis.

You may react differently than 99.9% of other people to having a
massage or being dehydrated so if you want to know what a massage
would do to you, a journal of medicine or google search has very
little, if any, gravity regarding you as a unique person. Personal
experience is pretty valuable.

Really this is something anyone can do if they have a dictionary to
stand on and some water to drink, plus the excercise can't hurt. I'm
assuming this question was for for the purpose of writing a paper so
this information may really only be relevant to others who search this
same topic.

Massage is a ripoff.

Excuse me, but massage is not a myth. If it was, Greek Olymixc
trainers would not have subscribed to this treatment for 700 years of
Ancient Olympic training.  However, as in most areas of health
affecting the human body, the effects of the medical treatment are
strongly tied to the quality of the doctor, or practitioner. I have
tried many types of massage:

1- A highly physical massage by a heavily muscled turkish bath
attandant in Istanbul- outstanding results in terms of relaxation and
reduction of muscyular tension;

2- A whole body massage by another bath attendant who did not exert
himself; result: no clear benefits felt afterward.

3- A scientific massage by a 55 year old Kashmiri man who is not
licensed professionally, but was trained by his grandfather in an
ancient healing system that is thousands of years old. I call it
scientific because this man would study the patient, and tie the
external condition or symptoms, to specific internal deficiencies. In
my case, while examining me, he saw that I had a yellowish overall
skin tone that clearly showed that I was unhealthy; usually this
yellowish coloring is caused by Jaundice which in turn has  various
possible causes in the body. Anyway, he explained to me, in his own
way, that my waste liquids are not being removed properly from my
tissues. This was a very interesting explanation to me, as I had
already studied Jaundice carefully and one of the causes is a poorly
functioning Lymphatic fluid system. This system is responsible for
carrying away the  waste fluids from tissue cells all over the body
and returning the fluid to the liver, where it is filtered out and the
waste materials are sent to the kidneys. A disruption in this process
can lead to a build up of toxins in the various tissues in the body. 
He gave me six one hour massage sessions, and after the second
session, I found a strong change in skin tone, no more yellow tint,
and a definate increase in energy. The massage was painful, as he
would concentrate on deep muscular massage of the legs, using his
hands of course, moving in an upward fashion, from toes to the upper
thighs and buttocks. In effect, he was squeezing the tissues very
strongly, just as you might squeeze a sponge, in addition to linear
movements, and the tissues would expel the internal fluids as a result
of this high pressure massage. Conclusion: His theory was correct, his
prectical treatment was painful but highly beneficial, and my yellow
skin tint has been gone for 8 months now. I agree fully that >>>
correctly done <<<< massage will remove toxins from the body, and
naturally to assist this process, extra liquids should be ingested to
reduce blood viscosity and increase kidney detoxification  by
supplying the necessary water. This way, the kidneys can contribute by
removing the toxic metabolic wastes that have been expelled by the
deep tissue massage.