Finnish has a word, sisu, that resists a clean English translation but roughly describes a capacity to keep acting through hardship, discomfort, or fear rather than a simple synonym for grit or willpower. For years it circulated mostly as cultural folklore. In 2022, a team of Finnish researchers led by Pentti Henttonen, Ilmari Määttänen, and Emilia Lahti tried to turn it into something measurable, publishing a validated psychometric scale in the journal Heliyon designed to assess sisu directly rather than take the folk concept on faith.
What they found complicates the version of “comfortable with discomfort” that gets repeated as an unqualified virtue. The Sisu Scale did not confirm a single trait. It split into two separable factors: a beneficial form, made up of extraordinary perseverance, an action mindset, and a sense of latent reserve power, and a distinct harmful form, involving harm to oneself, harm to one’s own reasoning, and harm to others. This is one validation study, not a settled account of the construct, but the split itself is the finding worth taking seriously: pushing through discomfort is not automatically healthy just because it is effortful.
What the two forms of pushing through actually predict
A follow-up study using the same scale, published in 2024 in Heliyon and based on 455 participants in a Finnish workplace wellbeing project, found that the beneficial form of sisu tracked with better mental and physical health, higher satisfaction, and stronger professional accomplishment. The harmful form did the opposite: it was specifically linked to intensified work stress, aligning with an established model of workplace strain in which high effort combined with low reward predicts burnout. Tolerating discomfort, in other words, is not one trait with one effect. Whether it helps or harms appears to depend on which version of it someone is actually practicing, something a person cannot necessarily tell from the outside, or even always from their own account of their own behavior.
Where the embodied version of this gets tested directly
Nordic winter swimming, dipping into near-freezing open water as a regular practice, is sometimes framed as a literal, physical version of building comfort with discomfort. A 2024 systematic review and meta-analysis in PLOS ONE pooled eleven controlled studies and 3,177 participants examining cold-water immersion’s effects on stress, mood, sleep, inflammation, and related measures. The results were considerably more mixed than the wellness framing usually suggests. Inflammation markers rose significantly in the hour immediately following cold-water immersion, a genuine acute physiological cost. Stress levels showed no significant change immediately afterward, at one hour, at twenty-four hours, or at forty-eight hours, and only became significantly lower a full twelve hours after immersion. Sleep quality and quality of life improved across the pooled studies. Mood did not improve by a statistically significant margin.
The review’s authors were also direct about its limits: six of the eleven studies tested only a single immersion rather than a repeated practice, which leaves the question of long-term, habitual cold exposure considerably less settled than the single-session data can speak to, and only one of the eleven studies included any female participants at all, a serious limitation on how broadly the findings can be applied.
What both bodies of research point toward together
Put the two findings side by side, and a more precise account of “getting comfortable with discomfort” emerges than either folklore or a single wellness headline tends to offer. The immediate experience of discomfort, whether cold water or a difficult task pushed through, does not reliably produce an immediate benefit; in the cold-water research, the body’s stress response briefly worsens before any measurable improvement shows up hours later. And the psychological trait that lets someone tolerate discomfort in the first place is not a single, uniformly good quality. The same capacity that shows up as beneficial perseverance in one person’s data can show up as self-harm or worsened stress in another’s, measured on the very same validated scale.
What this does not settle
Both bodies of research are still early. The Sisu Scale has been validated in Finnish samples specifically, and how well the same two-factor structure holds up outside Finland has not been established. The cold-water immersion meta-analysis is built mostly from single-exposure studies with a near-total absence of female participants, so it cannot speak reliably to what happens with a sustained, years-long winter swimming habit, or to whether the pattern looks the same for women. Neither literature settles whether deliberately seeking out discomfort is, on balance, a good strategy for any specific person. What both point toward is a more cautious middle ground: discomfort tolerance is a real and measurable capacity with a real physiological and psychological cost attached, not a shortcut to resilience that skips the cost entirely. The more useful question, based on what these two studies actually measured, may not be whether someone can tolerate discomfort at all, but which of the two directions their particular tolerance for it tends to run.