Imagine you’re running the toughest race of your life, dragging yourself through the last hours of an exhausting work week, or struggling through an emotional rough patch.

What do all of these situations have in common? They force you to draw upon a deep well of resilience, an internal energy that drives you to keep going and push past your limitations, bringing out a powerful mixture of courage, perseverance, and grit.

We can’t describe this inner power using a single English word, but the people of Finland (the happiest country in the world) have a hundreds-of-years-old term for it: “sisu.”

Pronounced “see-soo” — and one of several Scandinavian buzzwords to emerge in pop culture lately, following “hygge” and “pyt” — the term is hard to sum up in one neat definition. A study of more than 1,000 Finns and others familiar with the concept, led by doctoral student Emilia Lahti of Aalto University, activist and founder of the Sisu Not Silence campaign, found that the meaning of sisu can be described in many ways. Some refer to it as an “extraordinary perseverance” that pushes you forward when you think you’ve reached your limits, while others consider it an almost “magic source of power” that carries people through hard times; it’s akin to the British term “fire in the belly.”

Sisu centers on the notion that you are stronger than you think. It comes into play most visibly when the odds are stacked against us, when we reach crisis point and the end of our perceived strength. That’s the time to reach for the reserve fuel tank,” Joanna Nylund, author of Sisu: The Finnish Art of Courage, tells Thrive.

Though sisu originated in Finland, and was even called “the word that explains Finland” by The New York Times in the 1940s, Lahti explains that the concept itself is universal.

Sisu as a word is Finnish, historically. But sisu as the ability of humans to unearth latent hidden energy is universal,” Lahti says. “The ability to persevere through the transformative fire, through the challenges we face, is a key, integral part of human life. That is something that keeps the world going and moving forward.”

Sisu shows us that we can access deep reserves of energy to push past our limits, but it’s important to be careful that, when doing so, we don’t accidentally deplete them.

“Too much sisu… leads to a world where we drive ourselves to the point where we will break,” Lahti says. “If we constantly keep pushing without paying attention to what is happening within us, outside of us, in our environment… we are in danger of creating a world where there’s very little space for survival. Because what does not bend will break, ultimately. We can’t have a conversation about sisu without having a conversation about balance.”

Channeling sisu in moderation — and finding that balance — can be extremely beneficial. And it’s not just reserved for extreme adversity, either; Nylund says that it can be used to motivate yourself through smaller tasks every day.

“Even outside of crises, sisu is a form of tenacity that is useful in most situations in life, which is why it’s so beneficial to be aware of and nurture,” she tells Thrive.

Take a cue from the happiest country in the world, and channel your inner sisu with these tips.

Connect with yourself

“It all starts with the wisdom that is captured in a line from ancient Greece: ‘know thyself,’” Lahti says. “Practicing healthy sisu begins with knowing who we are, knowing our potential for exceeding ourselves, and knowing that what we see here in this moment is not the entirety of us.”

Nylund agrees. “Dare to connect with yourself on a daily basis, taking the time to sort through feelings and events rather than rush to the next thing. We excel at distracting ourselves, don’t we? But there is no way we can tap into our inner strength if we barely know who we are,” she says.

Whether your preferred method is meditation, a walk in nature, or another personal practice, take a few quiet moments each day to check in with yourself and identify where you want to go, and what your limits are. This will help you channel your sisu toward your goals in a healthy way.

Set small, manageable goals

If (like most people) you’re easily overwhelmed by large, burdensome tasks, try breaking them up into smaller but more achievable goals.

“Setting a simple goal and training yourself to stick with it is a great way to foster sisu,” Nylund tells Thrive. She also suggests using bite-sized goals as a starting point for going out of your comfort zone.

“A big secret is to not always choose the most comfortable option. Whatever builds character tends to build resilience. It takes practice, but gaining that healthy self-reliance is so rewarding,” she says.

To do this, Lahti says, it’s important to have honest conversations with ourselves and foster awareness of what is and is not working. She suggests noticing how you feel as you work towards your goals, and identifying the beginning of discomfort or tension, where sisu starts. From here, she tells Thrive, you can work towards expanding your sisu zone and accomplishing even larger goals.

Live with integrity

According to Nylund, sisu comes with internal acceptance.

Sisu and integrity are closely linked. Ask yourself: ‘Am I living according to my values? Do I have the courage to stand up for what I believe in and those weaker than myself? How about online — can I be proud of how I conduct myself there?’” she suggests. “This taps deeply into the notion of taking responsibility for my actions in this world and believing that I have the strength to impact it for good.”

When you believe in your own abilities and power to make change, you will believe that you can conquer even extremely challenging tasks as well.

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