Sometimes the therapist will give you a short explanation about flushing toxins that were released. I even heard one therapist say that it will cause your body to feel the benefits of the massage for longer. That made me wonder how many massage therapists are telling people to drink water without knowing why. The explanation about the toxins is the closest to correct, but still not quite accurate. What are all of these toxins that are being flushed out? Many MTs can't tell you. No need to worry. Your body isn't suddenly releasing a whole bunch of toxins into your system when you get a massage. If that were the case, massage therapy wouldn't really be all that good for you. So let’s break down exactly what is happening and why it is a good idea to drink water.
Interstitial fluid surrounds every cell of your body. It literally means fluid between cells. Think about a sponge filled with water. The water surrounds every part of the sponge. When you press on it, the water shifts and leaks out of it. It is a similar idea in the human body. Of course, we don’t leak water when we get a massage, our skin does a nice job of keeping the fluid in, but when you press on human tissue, the fluid within it gets pushed around. The same thing happens when you work out. As you stretch and flex your muscles, the fluid gets moved around.
Interstitial fluid contains metabolic waste. The fluid is how the waste from your cells is transported through your body toward your kidneys to be cleaned. As the fluid moves around, the metabolic waste also gets moved around. By moving the interstitial fluid more than it would normally be moved, massage can actually help to speed up the process of removal of the metabolic waste because it gets to your kidneys faster.
By getting more interstitial fluid to your kidneys, they have to work a little harder to filter out the waste. For this, your kidneys need water. If the kidneys don’t have enough water, they can’t filter out all of the metabolic waste, and it just goes right back into the interstitial fluid.
Metabolic waste is not toxic, and nothing terrible will happen if it doesn’t get filtered as well as it should. You may get a headache or feel nauseous, but it will pass. Of course to prevent the headache or nausea, you can just drink some extra water to help support your kidneys.
So in conclusion, you don’t have to drink water after your massage, but you may want to in order to avoid feeling a little ill afterward. Drinking water is a good idea anyway. It is good for your skin and tissue, and your body functions better when you are well hydrated.