Superlatives fall like thudding hooves in the Netflix documentary series “Fearless,” available on Friday. Bull riding is “definitely the most dangerous sport in the world.” It’s “the fastest-growing sport in America.” Professional Bull Riders, whose 2015 season the series chronicles, is “a global phenomenon.”

“Fearless” plays like an elaborate promo — the first name in the credits is Sean Gleason, a co-producer of the series and the chief executive of P.B.R. You might think of the recent $4 billion sale of Ultimate Fighting Championship to WME-IMG and wonder if the bull riding league is being groomed for a similar deal. But WME-IMG already owns it, having bought it last year for an estimated $100 million.

Between the entertainment-sports conglomerate WME-IMG and Netflix, the deep-pocketed streaming service, there was probably a lot of money available to produce four hours of television (across six episodes) about bull riding. “Fearless,” directed by Michael John Warren, looks good and moves smoothly. The graphic design and music are several levels above those of the cable reality series in this genre. Much of the series was shot in Brazil, which supplies riders to P.B.R. the way the Dominican Republic supplies shortstops to Major League Baseball, and the Brazilian unit captures misty, idyllic images of the ranches where the self-described cowboys train.

There isn’t quite enough content to fill those four hours, though. The wary but amicable relationship between American and Brazilian riders provides some diversion. Yet the competitions, including the season championship, aren’t terribly dramatic, except for the somber moments when paramedics have to be called into the ring. And most of the time is spent in endless discussions of why a man would devote his days to climbing on the back of a 1,500-pound bull that’s bred to buck, and trying to stay on it for eight seconds, over and over again. Is it the golden champion’s buckle? Is it the million-dollar grand prize? After the first hour, you don’t care anymore.