The summer Olympics and the World Athletics Championships have traditionally been held in July-August, but Coe said warming temperatures were increasingly causing problems for endurance athletes.

At the Tokyo Olympics in 2021 many competitors struggled with extremely hot and humid conditions.

Organisers had moved the race walk events and two marathons 800 kilometres (500 miles) north of Tokyo to Sapporo in the hope of cooler weather. That, however, did not materialise as the northern Hokkaido region battled a heatwave.

"It's a really important question because the fact is we now live in a world that is changing very fast, and climate change is in so many ways impacting on things that we do," Coe said ahead of the World Cross-Country Championships in Australia on Saturday.

"I think we're going to have to look at the calendar in a very different way in the years to come. I can't see how any of the immediate (heat) challenges are going to be resolved in the foreseeable future."

He gave as an example the US track and field trials several years ago in Oregon where they rescheduled the men's 5,000 and 10,000 metres because of soaring temperatures in June -- a time when it is usually milder.

"Had the (2024) Paris Olympic Games been last summer or the summer before, you would have been in exactly the same situation," he said.

"So I think we are going to have to spend a great deal of time thinking about what the calendar looks like and maybe... uncoupling some of the tougher endurance events from our world championships in the summer months."

© 2023 AFP