‘My talent is in the water.’ Black South Africans embrace kayaking.

As a kid growing up in South Africa, Nkosi Mzolo and his friends had a front-row seat each summer to Africa’s largest river kayak race, a 75-mile endurance paddle over bone-rattling rapids.

But as he sat on the banks of the Msunduzi River near Durban watching the paddlers stream by in a rainbow of bright spandex, he couldn’t imagine being in their shoes. “I thought that was a sport for white people,” he says.

But Mr. Mzolo happened to grow up straddling a revolution. When he was born, in 1988, Black South Africans like Mr. Mzolo couldn’t vote or live in most parts of the country, let alone play sports with white