They are too old, too exhausted or too financially stretched to wait for another year, after the pandemic forced its postponement.

One of them is 35-year-old Tetsuya Sotomura. When I met him on a sweltering afternoon earlier this week he was still hard at it in a converted factory building in a north Tokyo suburb, flying high into the air, spinning and tumbling on a massive trampoline.

Back in 2008 Tetsuya placed 4th at the Beijing Olympics, just missing a bronze medal. Since then he's fought injury that put him out of London in 2012 and Rio in 2016. Tokyo was to be his last hurrah, a hometown Olympics to end his trampolining career on a high. But another year is just too much.

"Back in 2008, if the Beijing Games had been postponed by a year I would have thought ok, it's another year to train, another year to grow," he tells me. "But now I am 35. A year feels like a very long time. So, I have decided retirement is the only option."

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