Was Nurmi ever formally declared a professional runner?
Yes
No
He was a semi-professional runner
The records are unclear
Answer
No, Paavo Nurmi was never formally declared a professional runner. He ran in many major competitions and set numerous world records, but he always did so as an amateur. This was in contrast to many of his competitors, who were paid to run by their sponsors.
The Flying Finn: Testing Your Knowledge on Paavo Nurmi!