[cesnja]

There were 20000-year old footprints discovered in Australia [1], the estimated speed of these barefoot runners was comparable to olympic sprinters.

[1] https://www.nationalgeographic.com/history/article/20-000-ye...

[mkl]

Subsequent work has revised that estimate downwards quite a bit: https://www.originalwisdom.com/wp-content/uploads/bsk-pdf-ma...

[yread]

It could be that those people were just better at running than us. Tech that makes shoes and track more springy makes things measurably faster