The modern pentathlon is an Olympic multisport that currently consists of fencing (one-touch épée), freestyle swimming, equestrian show jumping, laser pistol shooting, and cross country running.

[4] The initial program of the 2028 Olympics did not include modern pentathlon, but the 141st IOC Session in Mumbai, India, voted to approve the inclusion of the sport with its new format where obstacle racing replaces equestrian.

[8][9][10][11] One alternative view is provided by researcher Sandra Heck, who concluded that Viktor Balck, the President of the Organizing Committee for the 1912 Games, made use of the long tradition of Swedish military multi-sports events to create the modern pentathlon.

[8] The addition of modern to the name distinguishes it from the original pentathlon of the ancient Olympic Games, which consisted of the stadion foot race, wrestling, long jump, javelin, and discus.

[14][17] Further innovation and streamlining to maximise the sport's appeal, including changes to the fencing event, is planned for the 2028 Summer Olympics in Los Angeles.

[21] The governing body, Union Internationale de Pentathlon Moderne (UIPM) was founded in 1948 in Sandhurst, England during the London 1948 Olympic Games.

[9] In 2015 — and for the first time in the 2016 Summer Olympics — a system of an additional bonus round was added to épée fencing in international competitions.

From 1989 until 2009, the shooting discipline involved firing a 4.5 mm (.177 cal) air pistol in the standing position from 10 metres distance at a stationary target.

[24] There is a slight delay between the trigger pull and the laser firing, simulating the time it would take for a pellet to clear the muzzle.

[28][29] From the start of the 2013 season, the laser-run was changed to consist of four 800 m laps (increasing the distance to 3.2 kilometres) each preceded by laser shooting at five targets in 50 seconds or less.

[33] The riding discipline attracted criticism during the 2020 Summer Olympics after multiple athletes in the women's event struggled to control their randomly-assigned horses.

[42] A group known as "Pentathlon United" called for the IOC to investigate the UIPM's governance, and proposed a plan to maintain riding with rule changes to bring them in line with those of the International Federation for Equestrian Sports (FEI), and a focus on animal welfare.

[43] In May 2022, the UIPM announced it would hold an obstacle racing test event alongside the 2022 Modern Pentathlon World Cup final in Ankara, citing that it had received the most support out of the over 60 disciplines proposed, was more cost-effective, would help make the event more attractive to a younger audience, and was "compatible with the DNA of modern pentathlon".

[46] In October 2022, modern pentathlon's elected Athletes Committee launched a campaign entitled #OurFuture, highlighting the views of pentathletes in favour of the change.

[47] Athletes such as Olympic silver medallists Elodie Clouvel (France) and Ahmed Elgendy (Egypt) supported the transition when participating in a media conference at UIPM Headquarters in Monaco.

[48] In November 2022, the UIPM Congress voted 69–11 in favor of replacing riding with obstacle course racing; an associated motion established that the changes would take effect for junior competition in 2023.

[51] On 22 June 2023, the UIPM shared a poll of 1,500 Americans by YouGov that they commissioned in support of their decision to replace riding with obstacle course racing, citing that the survey showed that "45% of Gen Z and 41% of Millennials more likely to watch the Olympics on television if it featured a ninja-style obstacle race...taken as a percentage of the U.S. population, this would equate to nearly 45 million more people watching the Games".

"[56] The MoU was criticised by Pentathlon United, who questioned World Obstacle's finances (in particular, being funded solely by one person with no other commercial revenue).

[59] The Greek modern pentathlon coach said, "We are an Olympic sport that is on the edge... We're very, very low down, if not bottom, in a lot of ratings like ticket sales, viewership, and participation".

[60] However, KXAS-TV reporter Stephanie de Lancey called the compressed 90-minute format used at the 2024 Olympics "fast and action-packed" and said the replacement of show jumping for 2028 was "a way for the sport to evolve in the 21st century.

"[61] A 2021 study by Quartz concluded that modern pentathlon (in the form that included equestrian) was the most expensive Olympic sport for entry-level costs.