After Finland defended itself and repelled the Soviet invasion, a 1940 New York Times article described sisu as the "word that explains Finland".
"Finland was a small nation, but it showed that Finns were stubborn or dogged enough to fight against a bigger country, and sisu was presented as a Finnish national characteristic," researcher Tanja Helminen tells APN of the word that has come to take on huge historical and cultural significance in Finnish society.
APN takes a ride to Lahti's Ski Museum for an exhibition entitled 'Sweat, Sisu and Ski Heroes', where we hear from collection curator Laura Häkkinen about a trailblazing Finnish skier of the 1950s.
"[Siiri Rantanen] was a very resilient woman. She became an Olympian after she was a mother of two and a wife, and she worked full time and still became an Olympian," Häkkinen tells APN. "She is a really great example of sisu."
And we dive into the chilly Baltic waters off the coast of Helsinki with author and self-care advocate Katja Pantzar, who defines sisu as "fortitude, resilience and perseverance in the face of challenges, big or small".
"I make a practice of coming here every morning no matter how tired I am, or if I'm stressed, or if I'm feeling anxious or depressed. I come here, I dip in the sea and I leave it all behind in the sea," Pantzar explains.
We also round up all the rest of the week's news from Finland.
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This week's show was presented by Ronan Browne and the sound engineer was Juha Hjelm.
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