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Sisu: The Finnish Secret of Inner Strength and Resilience

Why we all need a bit of sisu to keep going through tough times.

Key points

  • Sisu is a Finnish construct that describes the ability to push through one’s limits when facing adversity and continue on against the odds.
  • While perseverance is usually seen a good thing, too much sisu may impair an individual’s judgment about when to give up and when to persist.
  • Sisu is likely not a uniquely Finnish phenomenon but a universal trait.

It’s a Sunday morning in Helsinki in early February. The sky is overcast, with occasional faint glimpses of sunshine breaking from the clouds. The temperature is around 0 degrees C, but the wind makes it feel much colder. I’m out for my usual workout, but the icy wind cuts right through my running tights, and I feel like I’m out there naked, having nothing on at all.

My hands suffer the most, my fingers frozen and numb from clutching the Nordic walking poles. I try different strategies, but the one that seems to work best is that I simply use one pole at a time while trying to warm up the other hand. By the time I reach the seaside promenade near Kaivopuisto Park, I’m reminded that there is no such thing as bad weather, just the wrong clothing.

The seaside walk is full of locals, all appropriately dressed in waterproof coats and matching pants. There are singles, couples, families, young and old, all enjoying their Sunday walk by the sea in these grueling weather conditions as if they were taking a stroll along the French Riviera. This must be the famous Finnish sisu, I find myself thinking, and I instantly wonder if some of it had spread over to me during my three weeks in Helsinki. Or perhaps, as a native of the neighboring country of Estonia, I might have sisu, too? The word, after all, has a similar etymology in the sister languages, pertaining to the inside or the inner contents.

Sisu, Sauna, and Sibelius

It’s been said that sisu is the favorite word of Finns, their ethnic symbol, and a cornerstone of the Finnish cultural and national identity alongside sauna and Sibelius (Palo Stoller, 1996). Sisu is “a word that explains Finland,” the New York Times declared in January 1940. Sisu is believed to be the social glue that helped to define the Finnish nation when Finland declared its independence from Russia in 1917, and it was at the heart of the Finnish resistance against the Soviet invasion during the Winter War in 1939-1940. I haven’t seen the link being made, but I wouldn’t be surprised if sisu was also seen as responsible for Finland having the most heavy metal bands per capita.

And yet, the exact meaning of sisu seems elusive and difficult to describe. The word cannot be easily translated, and it doesn’t have a direct equivalent in English or arguably in any other language. Even Finns struggle to define it when asked. This only makes it even more special and precious to Finns and adds to the hype that surrounds sisu outside of Finland, where it’s been claimed to be another Nordic export following the success of hygge, lagom, and fika. So what is it, then?

Three Qualities of Sisu

In the words of a Finnish psychologist and sisututkija (sisu researcher in Finnish) Emilia Elisabet Lahti, sisu is “an age-old Finnish cultural construct traditionally used to describe the ability of individuals to push through unbearable challenges” (Lahti, 2019). Despite sisu being one of the quintessential features of Finnishness, there are only a handful of studies that have studied the meaning of sisu in detail. When Lahti asked more than 500 Finns about how they would define sisu and analysed their answers using thematic analysis, the following three main components or features of sisu emerged.

  • Extraordinary perseverance. The first, and the most prominent quality of sisu relates to the ability to overcome one’s preconceived capacities, both mental and physical, when facing adversity and acting against the odds, by accessing and using one’s inner reserves of strength and energy. As the participants of Lahti’s study said, sisu “means not giving up even when the obstacles seem insurmountable”; it is “beating the odds, achieving what no one thought possible."
  • Action mindset. The second aspect of sisu can be described “as an action mindset,” that is, a tendency to take action when failure is a likely result. It’s about having guts and following what feels right and trusting oneself and one’s potential.
  • Latent power. The third important characteristic of sisu refers to its latent power. Sisu is an innate quality, an ultimate power potential that exists deep within individuals and that can be accessed and employed when things get really tough and one’s limits are tested and stretched. When it manifests, it “is almost like magic, in the sense that with it, you can do what others think is not possible."

In sum, sisu bears a similarity to concepts such as perseverance, resilience, grit, endurance, and willpower but as Lahti explains in her paper, none of these fully captures the meaning of sisu, which, in the words of Finns, often assumes almost supernatural or magical qualities.

Can Too Much Sisu Be Harmful?

While perseverance is certainly a good trait to have, there are times in our lives when the best possible choice is not to push through the impossible but to quit and move on. So can too much sisu be a bad thing? Henttonen and colleagues (2022) developed a scale to measure the psychological content of sisu and found that in addition to beneficial sisu—comprising the components described above—harmful sisu indeed emerged as an independent construct in their study. Constantly testing and exceeding one’s limits can cause harm, both mental and physical, not just to an individual but also to others around them.

People with too much sisu can become obsessed with their quest and become indifferent and even intimidating to others. Too much sisu may also impair an individual’s judgement about when to give up and when to persist. In Henttonen and colleagues’ study (2022), harmful sisu was associated with higher levels of stress and depressive symptoms and lower levels of well-being. Beneficial sisu, on the other hand, showed positive relationships with various measures of mental fortitude, well-being, and personality traits such as extraversion, openness, and conscientiousness.

A Concept With Universal Relevance

Despite being deeply embedded in the Finnish culture and national character, sisu researchers believe that sisu is likely not a uniquely Finnish phenomenon but a universal trait. Even if there are no exact equivalents of sisu in other languages, the underlying idea of some sort of unimaginable inner drive and fortitude that surfaces in extreme situations and keeps one going intuitively makes sense to most people, regardless of their cultural background. We all have and need a bit of sisu to endure and keep going through tough times. But, as with most good things in life, moderation is the key: Too much sisu can hold you back instead of moving forward.


Henttonen, P., Määttänen, I., Makkonen, E., Honka, A., Seppälä, V., Närväinen, J., . . . Lahti, E. (2022). A measure for assessment of beneficial and harmful fortitude: development and initial validation of the Sisu Scale. Heliyon, 8(11), e11483.

Lahti, E. (2019). Embodied fortitude: An introduction to the Finnish construct of sisu. International Journal of Wellbeing, 9(1), 61-82. doi:10.5502/ijw.v9i1.672

Pdoi:10.5502/ijw.v9i1.672alo Stoller, E. (1996). Sauna, sisu and Sibelius: Ethnic identity among Finnish Americans. The Sociological Quarterly, 37(1), 145-175. doi:10.1111/j.1533-8525.1996.tb02335.x

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