Transcript for Son Dies While Competing in Extreme Obstacle Course

We're back, now, at 7:42, with the tough mudder fitness craze. An Oregon mother is suing for the downing death of her son on one of the courses. Reporter: This morning, new questions about one of the fastest-growing competitions in the country is too dangerous. It's called tough mudder, an endurance competition with 35 events a year, and thousands of runners at each event. Subjecting them to an obstacle course several miles long, that includes freezing water, electric shock and plenty of mud. The mother of 28-year-old avishek Sengupta filed a lawsuit against tough mudder and its sponsoring saying that tough mudder acted with gross negligence and indeference to the safety of its participants. And had improper staffing. Sengupta died after participating in a tough mudder event in West Virginia. After jumping from an obstacle called walk the plank. You can see Sengupta jump from the ledge into the water and others jump right after him. But Sengupta never emerged. He was underwater for 8 to 11 minutes. And by that time, the trauma that had been done to him underwater was too severe. Reporter: Is there real danger in these extreme obstacle sports? Some experts say absolutely. You can't prepare for many of the obstacles. And that lack of training makes you more vulnerable. Reporter: Tough mudder and General Mills declined to comment on the lawsuit. But tough mudder said the event, quote, was staffed with more than 75 A.L.S., E.M.T., paramedics, water rescue technicians and emergency personnel. And Sengupta's was the first fatality in the three-year history of the company. Thank you, Ryan. Coming up, Ricki lake is here live this morning. Talking about her documentary

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