Hundreds of athletes, including U.S. sprinter Justin Gatlin, participated in a test event at the Olympic Stadium on Sunday, as organisers fined tuned operations and practiced Covid-19 countermeasures with under three months to go before the Tokyo Games begin.
No spectators were present in the stadium, where the Olympics opening and closing ceremonies will be held, as Tokyo remains under a state of emergency to tame a rise in coronavirus infections.
Sunday's event, involving 420 athletes, including nine from abroad, was split into morning and evening sessions with Gatlin on the start list for the 100-metre in the evening.
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Despite the state of emergency, organisers have operated more than 11 test events since last month with no reported coronavirus cases resulting.
Four of those of events - volleyball, diving, marathon and Sunday's athletics - included athletes from abroad.
Opinion surveys have shown that most Japanese oppose holding the Games this summer due to worries about the pandemic.
World Athletics President Sebastian Coe sought to ease those worries.
"We are very empathetic to the need to be fully recognising that communities around the world are inevitably nervous about many things related to Covid," he told a news conference at the stadium.
"We take those concerns very, very seriously. The Covid protocols, particularly that World Athletics have developed over the last year and a half by our health and science teams who are extremely good at this, have consistently helped deliver events in a safe and secure environment."
Many athletes, however, want the Games to go forward.
"People are really worried about people coming from overseas as coronavirus variants are spreading, but as an athlete I want the Olympics to be held with people from various countries running," said Suzuha Kobari, after participating in the women's 100 metres in the morning session.
Japanese rhythmic gymnast Nanami Takenaka said at a separate test event the previous day she understood there were opposing views, but that gave her team an extra reason to bring cheer through their performances.
"We'll focus on the things that we can do and when the Olympics are held we want to give our best performance so that people can smile and feel glad they took place," she said.
Sunday's morning session also included the men's shot put, the women's triple jump and the women's 200 metres.
The evening session is to include several events including finals for the pole vault, high jump, javelin throw and the men's 100 metres.
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