Dwindling interest and a reputation for being outdated couldn’t change modern pentathlon. A brief video clip of a coach punching a horse at the Tokyo Olympics has altered it forever.

After more than a century of having its participants compete by running, shooting, fencing, swimming and riding, modern pentathlon will drop equestrian jumping from the event, the sport’s federation said Thursday. The decision came after two members of Germany’s Olympic team were accused of mistreating a horse at the Tokyo Games.

A replacement sport for riding will be named later, the federation said. Several news reports said competitors would continue to ride in the event — by trading horses for bicycles — but the organization made a point of disputing that: “It is untrue to say it will be replaced by cycling,” it said.

The federation said Thursday that it would not add a sport that “falls under the governance of another I.O.C.-recognized international federation.” That would seem to rule out any other Olympic sport, like cycling, rowing or canoeing, as well as I.O.C. recognized non-Olympic sports, a wide list that includes karate, squash, billiards and chess.

The federation cited several criteria for the replacement sport, including that it “be attractive and relevant for global youth and future generations,” “be exciting and easily understandable for TV” and “be low-cost for both athletes and organizers.”

The change will take effect after the 2024 Paris Olympics, the federation said, and the sport’s horse-free future will be in place in time for the 2028 Games in Los Angeles.

Thursday’s announcement came three months after an incident involving the mistreatment of a horse at the 2020 Tokyo Games cast an unwelcome spotlight on modern pentathlon. Unlike in the standard equestrian competitions at the Olympics, competitors in the sport are randomly assigned horses for riding rather than providing their own. Sometimes those horses perform flawlessly. Other times they do not.

In Tokyo, that led to accusations of abuse after a German pentathlete and medal contender, Annika Schleu, was assigned a stubborn horse that refused to jump at all. Her coach Kim Raisner was captured on video punching the horse while Schleu tried to get it to continue, and Schleu was accused of whipping it excessively. Schleu denied the charge, but Raisner was sent home from the Games.

But that incident, and the death of a horse injured in an equestrian event at the Tokyo Games, led some animal rights activists to call on the International Olympic Committee to remove equestrian sports from the Olympic program altogether.

Changing one-fifth of a sport like modern pentathlon, though, will have a significant effect on athletes who have trained in the traditional disciplines for years. The federation seemed to acknowledge as much in setting the ground rules for any new sport, insisting that it “be easy to learn and train based on athletes’ existing skills.”

“If it changed to cycling, I wouldn’t be in the sport,” the reigning men’s gold medalist, Joe Choong of Britain, told Sportsmail this week. “It would not suit me at all. I am sure a lot of athletes would feel the same.”

But Greg Whyte, another British Olympian, told The Guardian: “I don’t think it is necessarily a bad thing. All sports evolve, and no sport is immune from change in the modern TV era.”

One might say the modern pentathlon is neither modern, nor a pentathlon. Although it joined the Olympic program in 1912, it is called “modern” to contrast it to the ancient Greek pentathlon, which included wrestling, running, javelin, discus and long jump. The current disciplines were said to have been chosen to represent the skills required of a military cavalry officer.

There have been several efforts to, well, modernize the modern pentathlon in recent years, as the sport, generally near the bottom of Olympic popularity rankings, has fought to stay relevant. Notably, running and shooting were combined into one event in 2012, making the pentathlon more of a quadrathlon.

Once a five-day event, modern pentathlon was reduced to a single day in 1996, and plans are underway to conclude the whole competition in a rapid-fire 90 minutes at the Paris Summer Games in 2024.

These changes came in part because as the Games add sports with youth appeal, some creaky events like modern pentathlon might begin to seem irrelevant. The sport’s Olympics place has seemed threatened on several occasions.

A quaint element of modern pentathlon is that it comes with a story: Envision a soldier trapped behind enemy lines. He might ride a horse, fight with sword and pistol, run and swim to reach safety. The pentathlon simulates this little tale in an athletic setting.

That story will have to change.