The 47-year-old is set to compete in the T13 1500m and 5,000m events at next year's Paralympics, postponed to August 24 to September 5 as a result of the COVID-19 pandemic.

Kirwa revealed it would be his last Paralympics. 

"Tokyo Games will mark the end of my Paralympic career, but I am not done yet," he said.

"I shall compete in marathon after Tokyo Games.

"I'm no more a young man, I'm now 47. 

"All sports people face this grim reality some time or the other. 

"As years advance, focusing on one event would be good – I have chosen the marathon.

"I will be able to concentrate on building my endurance and stamina, a key need of marathon running." 

Kirwa first competed at Beijing 2008, earning Paralympic gold in the T13 1500m and 5,000m, and T12 10,000m. 

He finished with bronze in the T12 5,000m at London 2012, before upgrading to gold in the same event at Rio 2016 and claiming another bronze in the T13 1500m.

Kirwa also acted as Kenya's flag bearer for the Opening Ceremony of Rio 2016. 

With the global health crisis disrupting the sports calendar, Kirwa had to sell 40 trees from his farm to cover expenses. 

He was able to remain positive after qualifying for Tokyo 2020 in April, however. 

"The financial situation is not good as we are not getting support from the Government but we must keep training," Kirwa said. 

"I encourage my Paralympic family to remain strong and to keep training and not lose hope."