What if I told you that every morning you needed to bounce up and down on a trampoline simply to activate your brain? That, somehow, your brain had evolved to be sluggish and unresponsive until you had vigorously jumped up and down on a device that dates back to the 1930s? You probably wouldn’t believe me and for good reasons.
But a similar claim has been made for decades regarding the activation of a lesser-known part of our body: the lymphatic system. Often described as our waste removal network, it is too lethargic to be effective on its own, according to many websites. To improve its function, you need to bounce on a trampoline, an activity known as “trampolining” or “rebounding.”
Looking into this bizarre and risky recommendation, I was reminded of the wellness community’s obsession with detox and how little scientific evidence it needs to recommend something truly pie in the sky.
Much more than just a sewer
The lymphatic system used to be known as a “footprint” of our blood vessels, as one textbook puts it, an echo or shadow of it. As early as 300 BCE, our ancestors left records of their observations of “white blood” in the human body and of vessels that seemed to contain milk. We had to wait until 1622 for Italian anatomist Gasparo Asellius to clearly define these little tubes and give them a name: lacteals, after the root word for “milk.”
What these vessels transport is not milk but a liquid we now call lymph. It is made up of the fluid between cells, and as it circulates throughout the body, it picks up cells, proteins, and fat molecules and interacts with our blood. The dense network of vessels it moves through is connected via lymph nodes and organs like our tonsils, spleen, and thymus.
The more we study the lymphatic system, the more of its functions we discover. It absorbs what little blood leaks out from blood vessels and into surrounding tissues and recycles it. It can both promote inflammation and put an end to it. It absorbs fats from our diet. It plays roles in cancer, transplant rejection, and cardiovascular diseases. It is, as a review article notes in its title, “much more than just a sewer.”
But it is that function—in which lymph carries waste products and bits of cells, as well as potential pathogens for our immune system to recognize and fight—that has drawn the attention of the trampoline crowd. They believe that our lymphatic system needs a bit of help taking out the trash.
Over the moon about NASA’s study
The people who want to sell you the idea of trampolining (and often sell you the trampoline itself) will often say that, unlike your circulatory system, your lymphatic system doesn’t have a pump. Your heart pushes your blood around, but what pushes your lymph? Nothing. That’s why you need to jump! The quick changes in gravity cause your lymphatic vessels to expand, they claim, which maintains good lymph circulation.
It is true that the lymphatic system does not have a pump, but that’s rarely a problem. The vessels of the lymphatic system are made up of cells that overlap, creating one-way valves, allowing fluid to enter but not leave these vessels when enough pressure builds up. This fluid then moves according to pressure gradients that come about from our own respiration and the action of muscles. Pumps need not apply.
As for the claim that bouncing on a trampoline will help your lymphatic system detoxify you, this is simply the central tenet of the wellness movement: that modern living has poisoned our bodies with ill-defined toxins and that the solution is to detox. This is not true. Our lymphatic system, liver, kidneys, lungs, digestive system, and skin are more than capable of excreting the waste products our bodies create, and if we become genuinely poisoned, it takes a lot more than a trampoline, a special diet or colonic irrigation to reverse the process.
The idea of trampolining to speed up our body’s garbage disposal system is not new: I was able to find references to it on the Internet as far back as the year 2000. And yet, best of luck finding scientific studies lending support to the idea, or even simply investigating this hypothesis. The only one I could find was published in 2018 in the Journal of Alternative and Complementary Medicine and comes from Montreal. This pilot study recruited participants who had lower limb lymphedema, a condition that results from the accumulation of fluid in the legs. It can be difficult to treat and it makes regular activities like walking and gardening more difficult. Using compression bandaging and having the area massaged to drain it of its accumulated fluid can help, although the scientific evidence is of low quality. These Montreal researchers were curious to know if specific exercises, including the use of a trampoline, could help. Given that they only managed to recruit and test seven women in total, it’s fair to say that not much can be concluded from this pilot study.
But what about that famous NASA study, you may ask? Everyone who endorses trampolining to help the flow of lymph makes sure to mention that NASA studied this intervention and reported its benefits. The study itself dates back to many moons ago, 1980 to be exact. Its researchers were curious about the best type of exercise for astronauts to do in a zero-gravity environment to prevent deterioration of the heart, muscles, and bones. What they did is a very focused study of how fast various parts of the body accelerate during specific exercises. For example, how fast does an astronaut’s ankle go up and down in speed as the astronaut runs compared to jumping up and down on a trampoline. There was no measure of lymph flow or of accumulation of waste products. Nothing to do with the claims made by the trampolining crowd, which seems to have hitched its wagon to the wrong star.
If the evidence for trampolining doesn’t come from the scientific literature, where does it actually come from?
Canada’s first full-time practicing lymphologist
“Learning how to Lymphasize can completely change your life…” So states the now-defunct website of David G. Scrivens, a self-described “certified lymphologist,” Canada’s first, apparently.
It does not appear that Scrivens invented the idea of trampolining to speed up the flow of lymph in the body: webpages describing the phenomenon in the early 2000s make no mention of him. But he is frequently cited and quoted in more recent write-ups on the intervention and he seems to have popularized it.
What is a lymphologist? It’s unclear to me. According to his two LinkedIn profiles, he studied electronics engineering at the Algonquin College of Applied Arts and Technology to become first a technician, then a technologist. He also holds a yoga certificate from the PranaShanti Yoga Centre. On his YouTube channel, he claims to have gone to “lymphology school” and to be “one of the engineers of the original Canadian Internet.” He now sells “hydrogen kits” that guarantee better miles-per-gallon on the highway.
An archived copy of his website from 2005 looks like a parade of red flags. He asks his visitors if they want “total body detox.” He rattles off a list of diseases he can help with, including cancer and multiple sclerosis. He quotes Einstein. He pronounces himself an “International Ambassador of Health & Peace.” And he, of course, highlights the one true cause of all diseases: a dysfunction of the lymphatic system.
“We are zero-disease specialists,” an ad for his services proclaims in a 2009 edition of Ottawa Natural. “Corporate Packages Available.”
I have nothing against exercise. In fact, it’s the closest thing to a miracle drug we have. But there are safer exercises than jumping on a trampoline, irrespective of whether or not you think it might help your lymphatic system. The U.S. Consumer Product Safety Commission revealed that there were more than 300,000 trampoline injuries in 2018 in the United States that required medical treatment. To be fair, over 90% of trampoline injuries are sustained not by adults but by children (mostly between the ages of 5 and 14), which is why the Canadian Paediatric Society recommends that parents not buy trampolines for their children or teenagers. While websites endorsing trampolining are quick to say that it is a safer activity than jogging or running, I’m not sure where they are getting their information. Running can result in sprains, blisters, pulled muscles and skin injuries, but bouncing on a trampoline ups the stakes with fractures, dislocations, and head injuries. We all have different risk thresholds, but we should not delude ourselves that jumping up and down on a trampoline is safer than running on an even surface.
The problem with trampolining is that it is a hazardous solution to a non-existing problem. Your lymph probably does not need help circulating around your body, and if it does (because you have lymphedema), there are much less dangerous interventions to help with that, like compression and manual lymphatic drainage.
Trampolining is yet another strange idea, sold to the worried-well as all-natural and empowering. But when we look past the best justification for it—that exercising is generally beneficial to our physical and mental health—we find a complete absence of evidence and an unscientific justification based on the irrational fear of toxins.
No need to jump on this particular bandwagon, with or without the assistance of a trampoline.
Take-home message:
- Trampolining or rebounding is the practice of bouncing on a trampoline in an attempt to help your lymphatic system do its job of removing so-called toxins from the body
- Detox in the context of wellness is an unscientific idea, and there is no evidence to show that using a trampoline improves the flow of lymph in the body
- Unlike claims found on the Internet, trampolining is not likely to be safer than running or jogging, as the types of injuries sustained while trampolining tend to be more serious
