If women want to lean in to work, they may first want to lay down for a good night's rest. A Washington State University-led study indicated that sleep quality impacted women's mood and changed how they felt about advancing in their careers. Meanwhile, men's aspirations were not impacted by sleep quality.

The researchers discovered this finding in a two-week-long survey study of 135 workers in the U.S. Each day the participants first noted how well they had slept and the quality of their current mood, and then later in the day how they felt about striving for more status and responsibility at work.

"When women are getting a good night's sleep and their mood is boosted, they are more likely to be oriented in their daily intentions toward achieving status and responsibility at work," said lead author Leah Sheppard, an associate professor in WSU's Carson College of Business. "If their sleep is poor and reduces their positive mood, then we saw that they were less oriented toward those goals."

For the study published in the journal Sex Roles, Sheppard and co-authors Julie Kmec of WSU and Teng Iat Loi of University of Minnesota-Duluth surveyed full-time employees twice a day for two consecutive work weeks for a total of more than 2,200 observations. The participants answered questions about their previous night's sleep and current mood around noon every day and in the evenings answered questions about their intentions to pursue more responsibility, status, and influence at work.

Both men and women reported good and bad sleep quality over the course of the study, notably with no gender difference in reported sleep quality. However, women more often reported lowered intentions to pursue more status at work on days following a night of poor sleep.

The researchers can only speculate about exactly why sleep's impact on mood effects women's aspirations and not men's, but they suspect it may have to do with gender differences in emotion regulation as well as societal expectations—or some combination of these forces.

Neuroscience research has shown that women tend to experience greater emotional re-activity and less emotion regulation than men, and this can be reinforced by cultural stereotypes of women as more emotional. At the same time, stereotypes of men as being more ambitious than women likely add more pressure for them to scale the corporate ladder, so perhaps poor sleep quality would be less likely to deter men from their work aspirations.

These findings hold some good news for women who want to advance their careers, though, Sheppard said. For instance, they might take some practical steps to improve work aspirations, ranging from practicing meditation to help with both sleep and emotion regulation to putting better boundaries on work hours—and of course, simply striving to get better sleep.

"It's important to be able to connect aspirations to something happening outside the work environment that is controllable," she said. "There are lots of things that anyone can do to have a better night's sleep and regulate mood in general."