YOU SAID:

On that day, for no particular reason, I decided to go for a little run

INTO JAPANESE

その日は特に理由もなく、ちょっと走りに行くことにした

BACK INTO ENGLISH

That day, I decided to go for a run for no particular reason.

INTO JAPANESE

その日、特に理由もなくランニングに行くことにした。

BACK INTO ENGLISH

That day, I decided to go for a run for no particular reason.