An extreme fitness athlete has triggered a biohazard row after she soiled herself and carried on competing while covered in faeces.

Joanna Wietrzyk became unwell while taking part in the Hyrox event in Beijing on Saturday, but pushed on to win the competition.

Pictures and videos from the competition, which The Telegraph is not publishing, show faeces running down the Australian athlete’s legs, on to the mats and some equipment.

Ms Wietrzyk, a Hyrox world champion, posted a photo on social media afterwards from what appeared to be a hospital bed. Its caption read: “Go hard or go home … a win is a win. In all seriousness, thank you for all the support. I’ll be back soon x.” She later deleted the post.

Hyrox is now being forced to review its procedures after it was accused of causing a biohazard for not withdrawing Ms Wietrzyk or closing off the soiled areas.

Hyrox is an indoor extreme fitness competition which involves athletes alternating between running and exercises such as burpees, rowing and a sled push. It has surged in popularity in recent years.

Ms Wietrzyk, who won the race in a time of 1hr 1min 23secs, was criticised online, as were organisers, given that Hyrox penalises acts such as spitting and littering.

Hyrox said it launched a “major clean-up operation” by sanitising equipment and replacing sections of the carpet.

However, Ms Wietrzyk’s fellow participants have demanded an apology and a refund, arguing that they came into contact with contaminated equipment.

Joe Ho, a male competitor at the event, said: “For people who were exposed to that situation, there could be genuine physical and psychological consequences.

“I paid Hyrox to provide a professionally organised and safe event. So while I understand the athlete perspective, ultimately my contract and expectation is with Hyrox.

“If the organisation accepts that something went wrong, why not offer affected participants refunds, credits, or some meaningful form of compensation?”

Participants have questioned why the fitness company allowed Ms Wietrzyk to continue.

Erica Dodge, a US-based nurse, wrote on Instagram: “From a basic health and sanitation standpoint, the athlete should have been stopped immediately, and any contaminated areas should have been closed off and properly cleaned before other athletes were allowed through.”

In a statement published on Monday, Hyrox said it had “clear biocontaminant and medical procedures in place”.

It said: “In this instance, an unforeseen situation arose in which protocols designed for elite competition and mass participation became blurred, creating ambiguity in how they were applied and understood.”

It added: “We recognise that this can understandably lead to frustration, questions and strong views within our community. Those concerns are legitimate and, as organisers, we must be prepared to hear them, examine what happened and take responsibility for continuing to improve. And we will.” The German company criticised the online abuse directed at Ms Wietrzyk.

Athletes relieving themselves in high-intensity endurance events is not uncommon.

Paula Radcliffe, the former marathon runner, was forced to relieve herself on the side of the road at mile 22 during the London Marathon in 2005 because of severe stomach cramps. She went on to win the race.

Gary Lineker also soiled himself on the pitch while playing for England against Ireland at the World Cup in 1990. He called it the most horrendous experience of his playing career.