The most amusing study that I've read in a while, but hey, if it works - why not? Bottom line: Riding certain types of roller coasters (such as Big Thunder Mountain at Disney World) enables some people to pass kidney stones. Kidney stones are small, hard mineral deposits that form inside the kidneys, affecting up to 15 percent of people in developed countries.
The researchers made a model kidney (and used actual kidney stones and urine) and brought it on the roller coaster ride multiple times - and found that what they were hearing from patients was true. Riding the medium intensity roller coaster dislodged the kidney stones in many cases so that they can be passed. Can you imagine a prescription for kidney stones that says "Go ride a roller coaster"? Note that "the ideal coaster is rough and quick with some twists and turns, but no upside down or inverted movements." From Futurity:
Riding a roller coaster helps patients pass kidney stones with nearly a 70 percent success rate, research shows. David Wartinger, a professor emeritus in the department of osteopathic surgical specialties at Michigan State University, led both a pilot study and an expanded study to assess whether the stories he was hearing from patients were true. “Basically, I had patients telling me that after riding a particular roller coaster at Walt Disney World, they were able to pass their kidney stone,” Wartinger says. “I even had one patient say he passed three different stones after riding multiple times.”
This resulted in Wartinger going out and testing the theory. Using a validated, synthetic 3D model of a hollow kidney complete with three kidney stones no larger than 4 millimeters inserted into the replica, he took the model in a backpack on Big Thunder Mountain at the theme park 20 times. His initial results verified patient reports. “In the pilot study, sitting in the last car of the roller coaster showed about a 64 percent passage rate, while sitting in the first few cars only had a 16 percent success rate,” Wartinger says.
The expanded study, conducted with Mark Mitchell, a Michigan State University resident at the time, included riding the same roller coaster with multiple kidney models attached to the researchers. They discovered even better results while sitting in the back of the coaster, with a passage rate of nearly 70 percent. They also found that both studies showed a 100 percent passage rate if the stones were located in the upper chamber of the kidney.
“In all, we used 174 kidney stones of varying shapes, sizes and weights to see if each model worked on the same ride and on two other roller coasters,” Wartinger says. “Big Thunder Mountain was the only one that worked. We tried Space Mountain and Aerosmith’s Rock ‘n’ Roller Coaster and both failed.” Wartinger went on to explain that these other rides are too fast and too violent with a G-force that pins the stone into the kidney and doesn’t allow it to pass. “The ideal coaster is rough and quick with some twists and turns, but no upside down or inverted movements,” he says.
Lithotripsy, which breaks apart kidney stones that are too large to pass, is a common treatment for the problem. Wartinger says the procedure is usually used in cases where the kidney stone is larger than 5 millimeters. “The problem though is lithotripsy can leave remnants in the kidney which can result in another stone,” Wartinger says. “The best way to potentially eliminate this from happening is to try going on a roller coaster after a treatment when the remnants are still small.” He adds that patients could even try going on a coaster once a year as maintenance, lessening the chances of future issues and minimizing health care costs.
The original pilot study from the Journal of the American Osteopathic Association: Validation of a Functional Pyelocalyceal Renal Model for the Evaluation of Renal Calculi Passage While Riding a Roller Coaster