Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

Russia's Darya Klishina prepares for the women's long jump qualification during the athletics competitions of the 2016 Summer Olympics at the Olympic stadium in Rio de Janeiro, Brazil, Tuesday, August 16, 2016. She might be feeling the pressure of being all alone, but Darya Klishina could yet still win Russia's only athletics medal at the Rio 2016 Games. (Photo by Matt Dunham/AP Photo)

The coendou porcupine couple 'Joppi' (L) and 'Fletcher' nibble at a vegetables in their enclosure at the zoo in Frankfurt am Main, Germany, 03 December 2015. Coendou porcupines are nocturnal rodents related to porcupines and guinea pigs and native to the rain forests of Central and South America as well as Trinidad. (Photo by Arne Dedert/EPA)

Downhill bikers Kemal Mulic (R-L), Tarik Hadzic and Kamer Kolar train on the disused bobsled track from the 1984 Sarajevo Winter Olympics on Trebevic mountain near Sarajevo, Bosnia and Herzegovina, August 8, 2015. Abandoned and left to crumble into oblivion, most of the 1984 Winter Olympic venues in Bosnia's capital Sarajevo have been reduced to rubble by neglect as much as the 1990s conflict that tore apart the former Yugoslavia. (Photo by Dado Ruvic/Reuters)

A man looks at kebabs cooking on the street side in Rawalpindi, Pakistan October 2, 2017. (Photo by Caren Firouz/Reuters)

A Muslim worshipper attends a mass prayer against COVID-19, the new coronavirus, in Dakar on March 4, 2020, after two cases were confirmed in Senegal in the previous days. Across the world, 3,155 people have died from the virus. More than 92,723 have been infected in 78 countries and territories, according to AFP's latest toll based on official sources at 1700 GMT on March 3, 2020. (Photo by John Wessels/AFP Photo)

A worker repairs fishing nets, which can stretch to more than 20 metres in length, in Sakon Nakhon, Thailand on August 12, 2021. (Photo by Chanwit Wanset/Solent New)

An Iranian girl wearing a costume inspired in the fictional folklore character Hajji Firuz, dances in Tehran on March 17, 2021 as Iranians prepare to celebrate Noruz, the Iranian New Year. Noruz, “new day” in Persian, is the New Year festivity celebrated in Iran as well as in Afghanistan and Kurdish regions in several countries. It begins with the spring equinox and symbolises rebirth. (Photo by Atta Kenare/AFP Photo)