If you’ve ever seen a TV commercial for inversion tables—those tilting contraptions that allow you to hang upside down by your ankles—and you suffer from back pain, you’ve probably been tempted to buy one.
The ads claim that by dangling upside-down, bat-like, you’ll create separation between the vertebrae of your spine and neck. That separation supposedly reduces pressure on the nerves running between and around these vertebrae. You’ll relax tense muscles, and increase the flow of “nutrients” to the disks of your spine—all of which should help relieve back pain and promote better physical health.
Beyond these apparatuses, yoga is also a big proponent of inversion. Assuming postures that elevate your legs above your head and lower body are said to be restorative—to help stretch the back and spine, and to increase blood flow to the brain.
These are all intuitive and appealing pitches. It’s easy to imagine gravity resting on your head and shoulders, squishing you down until your poor compressed bones and joints are nearly suffocated. By inverting yourself, it makes sense that you’d reverse this pressure and allow blood to flow more freely. Unfortunately, experts who’ve gone looking for evidence that inversion can do all this have mostly come up empty handed.
Maurits van Tulder, a professor of health sciences at VU University Amsterdam in the Netherlands, has studied the effectiveness of traction treatments for back pain. Traction is the application of a force that pulls two bones apart from each other, creating greater joint space. “The idea is that increasing the joint space between two vertebrae may free an entrapped nerve or relieve the pressure on [it],” he says. (What van Tulder describes sounds a lot like those TV commercials.)
He explains that traction is usually done either mechanically (with motorized devices) or manually (during a physical therapy or chiropractic treatment). “Hanging upside down is sometimes considered traction because gravity is the force that may draw apart two adjacent vertebrae,” he explains. “The question is whether the force of gravity is strong enough to increase the joint space between the vertebrae, and whether this would lead to a relief of symptoms.”
His research has shown that traction treatments—even the kinds performed with machines or a therapist’s able hands—are not effective remedies for back pain. Another recent review study came up with similarly disappointing results, he says, and inversion tables that rely only on gravity to create separation are unlikely to provide any back pain benefits.
“The evidence is quite convincing that traction is not a useful treatment,” van Tulder says. Inversion tables, he adds, are “a waste of money and misleading to patients.”
To understand why hanging upside-down doesn’t provide all those appealing spine-separating perks, it helps to understand how tightly the bones of your back are bound to one another. “There is so much muscle and tissue wrapped around the lumbar spine that it’s really hard to create separation [of the vertebrae] and decrease pressure,” says Dr. Edward Laskowski, co-director of Mayo Clinic Sports Medicine and a professor of physical medicine and rehabilitation at the Mayo Clinic College of Medicine.
Simply dangling upside-down is unlikely to exert enough force to create meaningful separation, Laskowski says. Even if inversion could open up some space between the bones of your back, any pain reductions would be short lived. “When you stand back up and are challenged by gravity again, everything would go back,” he says. “So there would be a transient benefit, at best.”
He says that some people report feeling a drop in back pain after inversion. But like many pain conditions, back pain is notoriously susceptible to sham or placebo treatments. One recent study from Harvard Medical School found that back pain sufferers who took a pill they knew to be a placebo reported significant reductions in both pain symptoms and disability scores.
“The other thing to be aware of with inversion is that when you get the body upside-down, blood pressure increases, heart rate goes down, pressure in the eyeball builds and other physiological changes occur,” Laskowski says.
“Our bodies are not designed to be in inverted position,” he adds. “So people with hypertension or heart conditions or glaucoma probably shouldn’t try this.”
What should people with back pain try? “Stay active and try to maintain your ideal body weight,” he says. Losing one pound of weight from your front takes four pounds of pressure off your back, he explains.
Meanwhile, exercise really does boost blood flow to your muscles and joints. Strengthening the muscles around your trunk and spine also creates added protection against back pain. “These muscles can act like a corset and take the pressure off your spine by offering support,” Laskowski says. And while a single inversion pose in yoga, like headstand, may not be enough to allay pain, the practice of yoga—like many types of exercise—has been shown to be good for stubborn back pain.
“Everyone’s looking for a magic device or pill,” he says. “But it’s better to get back to the basics.”