One guest jumped out of the tube, causing it to overturn on the Tornado funnel slide, park spokeswoman Kristin Fitzgerald told NJ Advance Media.
The adult victim was hospitalized with back pain, the Asbury Park Press reports.
The 75-foot-high slide drops visitors down a 132-foot tunnel at about 35 feet per second, the Six Flags website says. The ride requires four-person rafts.
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