A striking exception is the National Geographic Channel’s new series “Knights of Mayhem,” in which athletes re-create Renaissance jousts in traditional armor but then, when their helmets are off, speak and act like trash-talking, chest-thumping 21st-century bros who have the sort of irrational beefs that are one of the plagues of reality television.

Since we first get to know the participants without their armor, the disparity between the gallant visuals and the vulgar, tiresome dialogue isn’t even momentarily comical. The action sequences are both too brief and too repetitive to make the hour work as a sports show. Viewers may stick around to watch a few equestrian wipeouts, but they’re likely to amble back to more familiar athletic competitions.

In the premiere, airing tonight at 9 p.m., we meet Charlie Andrews, who is attempting to take jousting, which he calls “the new extreme sport that is also the oldest extreme sport,” from Renaissance fairs and theme restaurants to arenas. He tells the camera that he is convinced jousting could be a billion-dollar business. He has invested all his money and gotten divorced while pursuing this dream.

Charlie sounds unfortunately similar to many other overbearing bosses in previous reality series. His conflicts with his associates often seem forced or faked.

For example, Charlie works with his former mentor, Patrick Lambke, who wears black armor. Charlie says that Patrick has had personal problems, but Charlie assures us that he won’t let Patrick interfere with his dreams. “If it comes down to it,” Charlie tells the camera, “I will cut his head off with a chainsaw and leave him on the side of the road.”

Later, after giving Patrick a big hug, Charlie tells him, “I’m not going to let anybody drag me down or derail the Charlie train. You either get on board, stay at the [bleep]ing depot or get ran the [bleep] over. Period.” Clearly, chivalry is not dead.

A contender named Brian Stephenson tells the camera that he’s angry with another veteran jouster, Jason Armstrong, because he believes that Jason gave him some misinformation that made him miss an important match.

When Brian shows up to prepare for a match, he confronts and then reconciles with Jason, and then repeats the process with Charlie. The scenes have the tired feeling of players going through the motions.

Charlie tells Patrick that he wants to leave the past (whatever it was) behind them. Then, while Charlie is introducing Patrick to some of his new recruits, he tells a long story about how Patrick deliberately injured him the first time they jousted.

All of this posturing seems designed to give us viewers a stake in who wins the first jousts, which are held in front of a small audience at a Renaissance faire. The climactic match, between Charlie and Patrick, plays out as it would if an unimaginative screenwriter were writing it.

The jousting footage is by far the most interesting part of the show. The scoring rules are easy to follow, once we get past the odd points:  For example, if a competitor breaks his own lance while scoring a legal hit, he gets extra points. Unhorsing one’s opponent, which happens often, is worth the most points, but it doesn’t count as a knockout. If the jouster can get back on his horse, the match continues.

The risk of serious injury or death adds suspense. Splintered lances reportedly have a way of finding vulnerable spaces in the armor.

The second episode covers the eight days leading up to and including the West Coast Jousting Championships, in Sonora, Calif. While training the newer jousters, Patrick and Charlie pick favorites. Again, this feels like an attempt to give us a rooting interest in people whom we don’t yet know well enough.

The personal relationships seem stuck where they were in the premiere episode. The action in the lists, however, is a more violent and consequently more interesting. Jason, a Canadian who is the most amiable of the principal characters, says that in the old days, the two winners of a tournament would be the two who weren’t in the infirmary.

Judging by the injuries we see, if Charlie is hoping to make jousting a major sport, he’s going to have to deal with those pesky state and federal boards that regulate things like safety and health. But there’s a bigger issue that goes unaddressed: Despite its grand name, the only competitors in the West Coast Jousting Championships seem to be Charlie and his team.

Knights were known for taking on difficult quests, but turning jousting into a major spectator sport seems impossible, even if Charlie is nobler and more idealistic than he appears on the show. The chances that “Knights of Mayhem” will be a hit are only slightly better.