Is Massage Moving Fluids And Causing Dehydration?
I recently listened to a presentation which talked about online arguments and how to handle things appropriately.
One of the points brought up by the presenter is to make sure you actually give credit to a person for putting themselves out there and being vulnerable. Whether the person makes a comment, writes an article or is just sharing information, it is important to recognize their effort.
A week or two ago an article was being circulated arguing that said getting a massage if you’re hungover is probably a bad idea and will make you feel worse because of the massage contributing to dehydration. While the writer made a great effort to inform people, the information isn’t exactly accurate and sadly is something still being taught in our massage education system.
Like so many of the other myths out there, we have to change our understanding and more importantly our patients understanding of what massage does and doesn’t do.
Is Massage Moving Fluid?
We’ve heard so much over the years about how massage increases circulation.
When I first started working in hockey, there was a player on the team who had a major health scare. He had blood clots in his lungs as a result of a Deep Vein Thrombosis and was put on blood thinners as a result. Once the clots were remedied, he went back to playing hockey but had to remain on the blood thinners. According to what we had been taught in school, this would have been a contra-indication to getting a massage. Being a worried student, I asked one of my teachers if a massage would increase his circulation enough to be a concern? His answer was profoundly simple – “no more than playing hockey would.”
That simple answer changed everything for me.
When we look into the research available concerning massage and blood flow, the results are again staggeringly simple. What do most people come in to get massage for? To relax!
Study(1) after study shows that getting a massage actually decreases blood pressure and heart rate. Other studies have shown that massage post exercise actually impairs blood flow and removal of lactic acid (another one of those wonderful myths), not increase it. While focused on the effects of sport massage, another study showed that massage did not increase femoral artery blood flow, but did increase skin temperature and skin blood flow to the area being treated (in this case the anterior quads). This showed a possibility of muscle blood flow being diverted to the skin, but also shows limited possibility of any metabolic change. Or the increase in skin temperature, could just be conduction of heat from the therapists hands?
One review on the subject points out that while some studies support the idea of massage increasing local blood flow it would also depend on the type of stroke used. The squeezing effect of some massage strokes could help to promote venous return (due to effect on skeletal muscle pump), but also points out the same strokes could temporarily occlude arteries causing a temporary reduction of blood flow, which would in turn cause an increase in blood flow when the pressure is released.
Overall there is not much evidence to support the idea of massage increasing circulation, or moving fluids around and certainly doesn’t increase it more than the effort it took for the patient walking into your clinic.
Photo by: RMTBC
Dehydration
There are a few ways to become dehydrated:
- Sweating too much (exercise, hot temperature).
- Diarrhea or vomiting.
- Urinating too much (i.e.: breaking the seal when you’re out drinking).
- Fever.
- And of course, just not drinking enough fluid.
Now, if someone is coming in after a night out on the town and are a bit (or a lot) hungover, they are probably already a bit dehydrated because alcohol is a diuretic, which in turn causes you to pee a lot. Then water loss is greater than water gain, and if body mass is reduced by 2% because of fluid loss, this causes mild dehydration. When blood volume decreases because of the fluid loss, blood pressure decreases, the kidneys and various nerve impulses trigger the thirst centre in the hypothalamus, telling us to drink fluids.
The other things that stimulate thirst:
- Your mouth is dry from decreased amount of saliva.
- Baroreceptors in the heart and blood vessels detect lower blood pressure.
I know what you’re thinking: “you just wrote a paragraph on how massage lowers blood pressure and now you’re telling me lower blood pressure causes dehydration!”
Not so fast.
The baroreceptors are sensing lower blood pressure and increasing thirst not dehydration. If your patient had been out drinking the night before, they’re already behind the eight ball as far experiencing some level of dehydration, so their blood pressure is probably already down to some degree because of the decrease in blood osmolarity. When we look at the mechanisms that actually cause dehydration, there is nothing happening in a massage that is causing sweat, diarrhea, urinating or fever. Nor is it possible for a massage to decrease body mass by 2% (otherwise we’d all be a lot busier!). Plus if a treatment could drop blood pressure that much, every person we treat would need to drink after their treatment.
While your patient probably wasn’t feeling great when they came in, a massage isn’t necessarily going to make them feel all that much better because their body is basically telling them they’re an idiot from the night before (my body has said this to me several times). The massage isn’t going to make them any more dehydrated than if I was at my buddies place and his kids were climbing on my back while I laid on his couch. But neither one is going to make me feel all that pleasant. So while it is nice to give your patients that bottle or glass of water after their treatment, can we do it just cause it’s nice, feels good and is good for them? And can we please stop telling them it’s because they’re dehydrated or the massage has released toxins that need flushing out?
References:
- Alan David Kaye, Aaron J. Kaye, Jan Swinford, Amir Baluch, Brad A. Bawcom, Thomas J. Lambert, and Jason M. Hoover. The Journal of Alternative and Complementary Medicine. March 2008, 14(2): 125-128. doi:10.1089/acm.2007.0665.
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Great article, thanks for sharing! So many people are still misinformed these days…