All athletes competing in the Tokyo Olympics must sign a document to acknowledge that they may face health risks or death caused by coronavirus infections and intense heat during the Games.

While it is normal for Olympic athletes to sign a waiver, the 2021 version includes a change in wording which protects the International Olympic Committee and the Japan organisers specifically against the consequences of the virus.

The existence of the new document was first revealed early last week by Jules Boykoff, an American academic, author and former professional soccer player. He writes extensively on the policies surrounding the Olympic Games and has been a strident critic of the IOC decision to press ahead with the Games.

At the time, athletes and coaches contacted in both Ireland and the US by Independent.ie were aware of the new controversial rule.

However, at a virtual forum last Thursday featuring IOC members and athletes’ representatives it was acknowledged by IOC President Thomas Bach that the document existed and that "this is concern for a number of you (athletes)."

Yahoo Sport obtained a copy of the new waiver. The relevant section states: "I agree that I participate in the Games at my own risk and own responsibility, including any impact on my participation to and/or performance in the Games, serious bodily injury or even death raised by the potential exposure to health hazards such the transmission of COVID-19 and other infectious disease or extreme heat conditions while attending the Games."

The 2016 form did not mention disease or heat even though there were concerns in Rio about the mosquito-borne Zika virus which resulted in a number of athletes including some of the world’s top golfers withdrawing from the Games.

Likewise, in 2010 the Vancouver Winter Olympics went ahead despite concerns about over the global outbreak of swine flu

IOC chief operating officer Lana Haddad confirmed that "entry forms have been in place for previous Games, and have been updated to include COVID-19-related consideration." She said that this was "to provide transparency and ensure the informed consent from the Games participants."

Haddad claimed that the waivers were "within the framework of the law." In a statement to Yahoo Sports, the IOC reiterated that claim.

Both also said that such waivers were "consistent with standard practice of other big event organizers," and indeed are common in amateur sports at all levels.

When asked via email by Yahoo Sport what would happen if athletes refused to sign the waiver, an IOC spokesperson did not directly answer the question.

An updated ‘Playbook’ – which is essentially a set of rules and guidelines – will be issued to athletes later this month.

The previous version released in April stressed that competitors must be accountable for their decision to take part.

“We trust that the measures laid out will mitigate the risks and impacts involved in participating in the games, and we fully count on your support to comply with them. However, despite all the care taken, risks and impacts may not be fully eliminated, and therefore you agree to attend the Olympic and Paralympic Games at your own risk,” it said.