There's a German word for the exact brand of tired you might be feeling right now: frühjahrsmüdigkeit. Yawn in front of a continental European around this time of year, and they will likely tell you you're feeling "spring fatigue." The phenomenon is strongly felt in German-speaking countries, but it is also casually diagnosed in Turkish, Finnish and Eastern European cultures.
The only problem: it's a total myth.
New research from Switzerland has found that the label of spring fatigue does not describe a real phenomenon, but instead only makes people pay more attention to their pre-existing tiredness. In the study, many participants said they suffered from spring tiredness. However, detailed questioning of hundreds of people over a year provided no indication of this. "That should have shown up in the survey data analysis," said study leader Christine Blume of the University of Basel.
According to their findings, the much-cited phenomenon is a myth, Blume and sleep researcher Albrecht Vorster wrote in the Journal of Sleep Research. The study argues that the phrase is so powerful because it is so firmly established, amounting to a kind of self-fulfilling prophecy.
Blume said she had the idea for the study because journalists regularly contacted her to explain spring tiredness. "There are numerous hypotheses to explain the phenomenon," Blume said. "But no one has ever checked whether it exists at all."
One common explanation is that rising temperatures dilate blood vessels and lower blood pressure. Hormones are also often cited — for example an excess of melatonin at the end of winter. "From a chronobiological perspective, that is entirely implausible," said Blume. "Melatonin is produced and broken down in a 24-hour rhythm. There is no kind of melatonin surplus at the end of winter that makes us tired and first has to be cleared."
To address the question, Blume and Vorster launched an online survey. From April 2024, 418 people provided information on their sleep quality and tiredness levels every six weeks for a year. While 47% said they themselves were affected by spring tiredness, the individual surveys provided no confirmation: There were no signs of increased exhaustion, greater daytime sleepiness or lower sleep quality in that season. "In spring the days get longer quickly," said Blume. "If spring tiredness were a real biological phenomenon, this transition phase is exactly when it should show up. But in the data, the speed at which day length changed played no role."
So where does the belief come from? Psychologists call this a labelling effect. "It has to do with our expectations," Blume explained. "If I expect to be tired in spring, that also changes how I interpret such 'symptoms'." Physicians speak of a nocebo effect — the confirmation of a negative expectation.
A further psychological explanation is cognitive dissonance reduction: as the cold season ends, we feel the urge to make use of better weather. If the necessary surge of energy fails to appear, spring tiredness offers a comforting explanation. Perhaps the most significant indication that the phenomenon is a myth is that the concept is entirely unheard of elsewhere. "When I tell colleagues in other countries about it, they are amazed," Blume said.