As Tokyo organized an athletics test event at the Olympics Stadium on Sunday, fake cheers, empty seats and the sound of pounding feet offered a glimpse of what a COVID-era Olympics, which Japan seems determined to hold at all costs, may look like.

The event brought home the reality of hosting an Olympics during the pandemic, with athletes competing in a muted atmosphere and excitement hard to muster.

Foot strikes echoed around Tokyo's 68,000-capacity Olympic Stadium during Sunday's track events, with recorded crowd noises reaching a crescendo as the runners approached the finish.

A fanfare of music greeted the end of the race, before the runners quickly departed down the tunnel, leaving a smattering of media and officials in the otherwise empty stadium.

"It's weird running in a stadium with no fans," U.S. sprinter Justin Gatlin said after winning the men's 100-meter event.

"It feels almost like a time trial or kind of like an intra-squad meet."

The athletics meet, one of a series of test events taking place in Tokyo, involved more than 400 competitors, only nine of them from overseas.

The atmosphere could be similar at this summer's coronavirus-delayed Games, with overseas fans already barred and organizers set to decide in June how many domestic spectators can attend, if any at all.

Although the test events are unusual, they lend weight to the argument that the Olympics can be held despite the pandemic, which has left Tokyo and other areas under a state of emergency.

There was more noise outside the stadium Sunday, with around 100 people protesting against an Olympics that polls show a majority of Japanese oppose.

"COVID-19 infection numbers are high in Tokyo and Osaka, with many severe cases," said protestor Takashi Sakamoto.

"I would like the money (for the Games) to be used in hospitals instead," he told AFP.

A new poll on Monday by the Yomiuri Shimbun daily found 59% of respondents want to cancel the postponed 2020 Games, which will open on July 23. The poll did not offer the option of a further postponement.

A separate survey by the TBS television channel found 37% back cancelation, while 28% want the Games delayed again.

'Beyond safe'

Japan's Prime Minister Yoshihide Suga was forced on the defensive on Monday, insisting in parliament he has "never put the Olympics first" and his priority remains "the lives and health of the Japanese people."

An online petition urging the Games be canceled has gathered more than 315,000 signatures since last Wednesday, but the organizers insist the mega-event can be held safely with strict virus rules.

"I felt beyond safe," said Gatlin. "I've been tested every day, either saliva or nasal swab every morning.

"The bubble has been very successful. The only time I've seen the outside is when we get on the bus to go to the track."

The rules were similarly strict at the Diving World Cup the previous weekend, which featured more than 200 divers from almost 50 countries somersaulting in silence with no fans present.

"We've been spitting in tubes a lot," said British diver Tom Daley.

There were some frustrations, with Germany's sports director, Lutz Buschkow, describing the restrictions as slightly claustrophobic.

"The most disappointing thing is that we can't breathe any fresh air. That's a really big burden for the athletes and trainers," he told reporters.

"It would at least be nice if we got a chance to walk in the hotel garden or car park ... it would be good if there was a way to fix these things."

Gatlin said he hoped organizers might be "just a little more lenient" come the Games, but that is unlikely.

In an indication of the risks, organizers reported two coronavirus cases during the events: a diving coach who tested positive on arrival in Japan and was quarantined, and a support member of a rowing team who tested positive during the competition.

But neither case forced a halt to events, and there were no immediate reports of additional cases being detected.