A Michigan State University study found that riding Big Thunder Mountain Railroad helped some riders pass kidney stones, with the back cars performing best.

Riding Disney's Big Thunder Mountain Railroad roller coaster might help pass kidney stones, particularly in the back carriages. This is a fun twist on medical advice, suggesting an amusement park ride could offer a surprisingly simple and effective treatment for a common ailment, potentially saving people a trip to the doctor.

Riding the Big Thunder Mountain Railroad roller coaster at Disney World can help patients pass small kidney stones, particularly if they sit in the back row of the ride vehicle. This medical phenomenon was verified by researchers who found the G-forces and vibrations of the ride successfully dislodged stones in a high percentage of trials.

The Data at a Glance

Ride Location: Big Thunder Mountain Railroad, Disney World Researchers: David Wartinger and Marc Mitchell Institution: Michigan State University Success Rate (Front Seat): 17 percent Success Rate (Back Seat): 64 percent Ideal Stone Size: Less than 4 millimetres

Why It Matters

This research proves that mechanical vibration and centripetal force can serve as a non-invasive, low-cost therapeutic intervention for a condition that typically involves excruciating pain or expensive surgical procedures.

The Origin: A Patient’s Unexpected Holiday

The study began when patients reported an unusual pattern to Dr David Wartinger, an urologist at Michigan State University. One patient specifically claimed he passed a kidney stone after riding Big Thunder Mountain Railroad three times in a row.

To test the theory scientifically, Wartinger and his colleague Marc Mitchell created a synthetic 3D-printed model of a kidney. They loaded the model with three actual kidney stones of varying sizes and placed it in a backpack.

The researchers then boarded the ride at the Magic Kingdom in Orlando. They received permission from Disney staff to carry the simulated organ on the ride, ultimately filming and recording the results over 20 runs.

The Physics of the Back Row

The study, published in The Journal of the American Osteopathic Association, revealed that seating position is the primary variable in success. While the front of the train offered a modest 17 percent success rate, the back of the train—where the whip-like motions and centrifugal forces are most intense—resulted in a 64 percent success rate.

Unlike modern hyper-coasters that rely on extreme speed and inverted loops, Big Thunder Mountain is a centrifugal coaster with a bumpy, wooden-style track. The researchers noted that high-speed, smooth coasters like Space Mountain or Rock 'n' Roller Coaster were less effective.

The stones passed were all smaller than 4 millimetres. For stones of this size, the ride essentially acts as a manual agitator, helping the stone navigate the narrow passage into the ureter before it has a chance to grow large enough to cause a blockage.

Practical Applications

This discovery is more than a novelty for theme park fans. It offers a potential preventative strategy for patients who have undergone lithotripsy—a common medical procedure that breaks large kidney stones into smaller fragments.

Riding a coaster shortly after lithotripsy could help clear those remaining fragments before they regroup or cause secondary issues. It also suggests that people prone to stones might benefit from activities involving moderate mechanical jarring.

Interesting Connections

• Ig Nobel Prize: This study was so distinctive that it won the 2018 Ig Nobel Prize for Medicine, an award given to research that first makes people laugh, then makes them think.
• The Roller Coaster Effect: The study has prompted further discussion into how intense vibration affects other bodily functions, including gallbladder sludge and inner ear crystals.
• Historical Medicine: Before modern urology, doctors often suggested horseback riding or travelling in bumpy carriages to help patients pass stones, making the Disney treatment a high-tech version of an ancient remedy.

Does this work for all kidney stones?

No. The study focused on small stones under 4 millimetres. Larger stones may become lodged in the ureter, which can cause severe pain and require emergency medical intervention. Always consult a doctor before attempting a coaster-based treatment.

Why did they specifically choose Big Thunder Mountain?

The ride was chosen because it is rugged and jerky without being overly fast. The researchers found that the erratic, vibrating motion of this specific coaster was superior to the smooth, high-speed g-forces of more modern steel coasters.

Do I need to ride it multiple times?

In the initial anecdotal case, the patient passed three stones over three consecutive rides. The researchers suggest that multiple repetitions increase the likelihood of the stones moving through the kidney's internal architecture.

Key Takeaways

• Seating Matters: The back car of the roller coaster is nearly four times more effective at moving kidney stones than the front car.
• Specific Motion: The jerky, vibrating movements of a mine-train style coaster are more effective than the smooth loops of modern thrill rides.
• Preventative Potential: This method is most effective for clearing small fragments and preventing larger, more painful stones from forming.
• Academic Rigour: While it sounds whimsical, the study was a peer-reviewed project from Michigan State University that has changed how we view mechanical therapy.

While a trip to Florida is an expensive prescription, the data suggests that for certain patients, the wildest ride in the wilderness might be the most efficient way to avoid the operating table.