Many of us have been taught that volunteering to take on more is the way to demonstrate your ambition at work. But if you're a woman and you're constantly raising your hand to sign up for miscellaneous office tasks (and if you're regularly volunteering for tasks, you're probably a woman), chances are you're doing more to harm than help your career.
That's according to a recent Harvard Business Review study in which economics professors Linda Babcock, Maria Recalde and Lise Vesterlund found that women are most likely to volunteer for assignments that benefit the organization but have very little impact on their advancement at a company. Tasks like planning a holiday party, filling in for a missing colleague or serving on a committee, they say, are "non-promotable" duties that women often sign up for without realizing how this work can hold them back.
"This can have serious consequences for women," the report says. "If they are disproportionately saddled with work that has little visibility or impact, it will take them much longer to advance in their careers."
In a group exercise done with 696 University of Pittsburgh students, researchers found that when a volunteer was needed to complete a mundane task, women raised their hand to do the job 48 percent more often than men. And in situations where a manager wanted to quickly select someone to do an assignment, they more than likely chose a woman over a man to do the job, even when the manager was a woman.
"Both male and female managers were more likely to ask a woman to volunteer than a man," says the report. "This was apparently a wise decision: Women were also more likely to say yes."
According to the data, a request to volunteer was accepted 76 percent of the time by women, compared with 51 percent of the time by men.
"These differences matter because they help explain why, despite women's significant educational and general workplace advances, we continue to find vastly different promotion trajectories for men and women," says the report. "Women will continue to progress more slowly than men if they hold a portfolio of tasks that are less promotable."
Jessica Bennett, gender editor at The New York Times and author of "Feminist Fight Club," tells CNN Money that this issue is a combination of both internal and external sexism. As women, she says, "we think we need to be 'helpful' and 'nurturing' and take on these roles that are traditionally female." But she says more women will have to learn to say "no" when assigned these tasks.
Babcock, Recalde and Vesterlund explain that in addition to women saying "no" more often, managers also need to be more mindful of who they are consistently asking to complete these duties.
"Rather than asking for volunteers or asking women to volunteer because they are likely to say yes, managers could consider rotating assignments across employees, for example," write the authors. "Understanding that women volunteer more simply because men are reluctant to do so should also lead men to volunteer more themselves and should empower women to demand fairer treatment."
Lauren McGoodwin, CEO and founder of Career Contessa and creator of The Salary Project, notes that women also take on an unfair amount of "invisible work" at home, such as cleaning, cooking and child care.
"When women are busy doing household chores, they have less time for paid work," she tells CNBC Make It. "This ends up robbing women of their potential for advancing within their careers, earning a higher salary and contributing enormously to the economy's growth through their paid jobs."
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