Photo: Murray Head/Corbis

Women who have done both say that running a marathon is kind of like giving birth, in that the memory of the pain fades astonishingly quickly — or else you’d never, ever do the thing again. It’s not a perfect analogy, obviously: One event leaves you with an adorable, tiny human of your very own, whereas the other is significantly more likely to leave you with fewer toenails than you had when you started. Regardless, there’s some new evidence that marathoners, like new mothers, quickly forget the pain of the ordeal, according to a new study published recently in the journal Memory.

Psychologist and Science of Us contributor Christian Jarrett reported on the research at the British Psychological Society’s Research Digest, writing:

Przemyslaw Bąbel recruited 62 runners (39 men) who took part in the 11th Cracovia Marathon in Cracow, Poland in 2012. Moments after they crossed the finishing line he asked them to complete a series of questionnaires about the intensity of the pain they were in, its unpleasantness, and the positive and negative emotions they were feeling. The key finding is that when he contacted them again, three or six months later, and asked them to recall how much pain they’d been in at the end of the marathon, most of them underestimated the pain they’d experienced, both in terms of its intensity and unpleasantness.

Specifically, when asked right after the race, the runners rated their pain at 5.5 on average, on a seven-point scale. When asked again a few months later, that had dropped to 3.2.

Runners whose races went particularly poorly, in that they’d suffered more intense pain during the race, did tend to rate their pain higher than those whose races had gone okay (though even these runners rated the pain lower months later); this, of course, is evidence of the psychological component of the perception of pain. It also echoes a recent finding on the perception of pain among new moms, which found that the moments of peak pain in childbirth were what stood out; even a shorter birth with more intense pain somewhere in the middle was recalled as overall more painful than a longer birth with more consistently moderate pain.

Finding a reliable way to measure people’s pain is so hard to do, because, obviously, the way people experience pain is so subjective. And although there have been at least a few scientific inquiries into how people remember pain after the fact, Jarrett notes that this may be the first one to look at the subject from the perspective of exercise. Standard caveats apply — this is just a first glance at the subject and so more research is needed before anything can be said definitively. But at the very least, it does seem to suggest one reason why marathoners would repeatedly sign themselves up for the grueling race: They’ve forgotten how grueling it actually is!