The speed 'race' (Old Norse) and the human 'race' (Italian) are completely unrelated words that collided in English.
A competition of speed, in which participants attempt to complete a course or reach a goal in the shortest time.
From Middle English 'ras' (a rush, running, swift course), from Old Norse 'rás' (running, rush, race), from Proto-Germanic '*rēsō' (a rushing). The underlying sense is rapid forward movement. This word is entirely unrelated to 'race' meaning a group of people sharing physical characteristics, which derives from Italian 'razza' (kind
The two English words spelled 'race' — the competition and the human category — have completely different origins that accidentally collided in spelling. The speed contest comes from Old Norse; the human grouping comes from Italian 'razza,' probably via French, with no connection whatsoever to the Norse word.