It was an incident that triggered international headlines. But while an HYROX athlete's mid-race bowel movement has raised questions about hygiene and fairness, the urge to go is a familiar reality for many endurance athletes.
HYROX is a fitness and endurance race that combines 8km of running with exercises such as rowing, sled pushes and wall balls, carried out in indoor exhibition halls.
The co-founder of the global sport, Moritz Fürste, apologised on Monday after Australian athlete Joanna Wietrzyk soiled herself during a race in Beijing over the weekend and went on to win.
Footage posted on social media showed Wietrzyk, who holds the sport's women's solo pro world record, competing at stations with faeces on her legs.
"I apologise to all that were directly or indirectly affected, as well as to everyone who felt like we did not handle the situation like we should have," Fürste's statement said.
"HYROX made a mistake by not reacting immediately during the race."
Fürste said the organisation had immediately begun improving its event processes and had introduced new rules and procedures to prevent a similar situation from occurring again.
The incident preceded opposition online, with some arguing it had affected other racers' ability to compete in a safe and hygienic environment.
"These competitors pay hundreds of dollars to participate and spend weeks, if not months, training for these events. Their health, safety, and ability to perform should matter just as much as anyone else's," read one comment which received thousands of likes.
Critics also questioned why officials did not intervene, given HYROX imposes penalties for other acts such as spitting and nostril clearing.
It's not unusual for endurance athletes to experience gastrointestinal symptoms during competition, nor is it unheard of for them to continue despite soiling themselves.
During the 2005 London Marathon, eventual winner Paula Radcliffe stopped and relieved herself in view of TV cameras.
She later explained she had been running through stomach cramps — likely affecting her speed — because of her reluctance to relieve herself in front of "however many thousands of people were watching on television".
French race walker Yohann Diniz experienced intestinal issues during the 2016 Olympics, but continued walking for many kilometres despite soiling himself.
According to research by Monash University, strenuous exercise lasting two hours or more — running — appears to exacerbate gut disturbances.
Researchers estimate 30 to 70 per cent of athletes experience gastrointestinal symptoms, with endurance athletes susceptible.
Bec Hoschke, a former professional triathlete and Ironman champion who now coaches endurance athletes in Sydney, told SBS News gut health can be a "highly sensitive thing for many endurance athletes".
She said the HYROX incident was a "very difficult situation" for the parties involved: the competition, the athlete and her competitors.
"Athletes make enormous sacrifices for international competition," she said. "For some athletes, it's their living."
She said the issue was not only one of public health and hygiene but also of the health and well-being of the athlete involved.
"I can't imagine the mental impact all of this is having on someone. I think she's only in her early 20s as well. It's enormously confronting for someone to have to deal with at that age."
Wietrzyk reportedly posted on her Instagram story after the race showing herself attached to an IV, writing "go hard or go home they say... A win is a win", but later deleted the post.
Her coach, Chris Bayens, said what had happened was "extraordinary", "unforeseen" and difficult to comprehend in real time.
"Decisions were made under competition conditions by an athlete, judges and officials, all responding to a situation none of them could reasonably have prepared for," he wrote in an Instagram post.
He said discussion and review of those decisions was legitimate, but "the hatred and personal attacks that have followed are not".
"Sport occasionally produces moments that are imperfect and deeply human."
Hoschke said HYROX presents different considerations to more individualised endurance events like marathon running because athletes compete in a contained space and use shared equipment.
"I hope that the public and the people that are involved in the sport can get something out of this conversation for the benefit of the sport," she said.