Japan suffered a record heatwave this year with temperature reaching 41.1 degrees Celsius, raising concerns that similar conditions in 2020 could disrupt the Games.

At least 96 people died of heatstroke across Tokyo's 23 wards in July.

The Olympics in the Japanese capital are due to take place from July 24 to August 6.

The International Olympic Committee (IOC) established a working group to make recommendations in order to ensure the health of athletes and spectators would not be impacted if similar temperatures occur.

Concerns were particularly raised with regard to marathons, with both the Japan Medical Association and the Tokyo Medical Association calling for start times to be moved to 5:30am.

They argued the decision from the IOC and Tokyo 2020 organisers to move the starts time up 30 minutes to 7:00am was insufficient and could prove a health risk to spectators and athletes.

IOC President Thomas Bach, speaking after the second day of their Executive Board meeting here in the Japanese capital, admitted the situation remained a "work in progress".

He added that the working group are discussing proposals to combat heat in athletics, but also in rugby and in cycling disciplines.

"We have there a working group with representatives from the sports department to address this issue," Bach said.

"There are different proposals under consideration concerning in principle three sports.

"With regard to athletics the marathon and the race walks, while there is a rugby proposal not to have matches at noon time.

"Then there was a proposal for the BMX and mountain bike with regard to the scheduling of the event.

"These are now proposals which will have to be discussed with the IFs (International Federations) and with the Athlete Commissions.

"A decision will then be taken."

Bach added that the timing of a decision would also need to be considered.

"This does not only concern athletes but also spectators, referees and every participant at the Games," he said.

"Then they [the working group] will have to take the decision or make a recommendation to the Executive Board.

"The principle question is when to take a decision.

"We will not know when there is another heatwave, there may be one, there may not be one.

"They may have to evaluate what is better – whether to take a decision before the Olympic Games or maybe they need to wait until there is a reliable forecast for this period of time."

Tokyo 2020 chief executive Toshirō Mutō confirmed an interim report was given by IOC vice-president and Medical and Scientific Commission chair Uğur  Erdener at their meeting today.

A final report is also expected to be delivered at the Tokyo 2020 Coordination Commission meeting, set to begin on Monday (December 3).

Mutō revealed that he hoped progress could be made by the conclusion of the three-day visit.

It is possible that the starting time of events could be earlier than originally scheduled or events starting in the afternoon could potentially be delayed until temperatures decrease, Mutō admitted. 

He added that the schedule would need to be worked on as soon as possible, because decisions could impact transportation, staff members, public transportation and rights holders.