Imagine that you've just arrived at work exhausted. As you walk to your office, a co-worker asks if you can help them with a task. If your first instinct is to say yes, a new study says you should rethink that.
Researchers from the Michigan State University found that helping a colleague complete their own tasks in the morning before your own exacerbates feelings of mental exhaustion and tiredness. This, in turn, decreases your productivity.
Scientists studied 91 full-time employees over a period of 10 workdays. Participants completed two surveys a day, in the morning and afternoon, on their workplace experiences.
"The increase in mental fatigue from helping co-workers in the morning led employees to reduce their helping behaviors in the afternoon," says Michigan State associate professor of management Russell Johnson in a statement.
"Perhaps more interestingly, they engaged in more self-serving political behaviors in the afternoon as well," he adds.
The research also found that when people don't focus on themselves first thing in the morning, these negative feelings and their mental exhaustion worsen throughout the day.
"They switched from being other-oriented in the morning to being selfish in the afternoon," says Johnson.
The study suggests getting your work done before helping a fellow employee to avoid these feelings in the office.
These findings are built off a 2016 Michigan State study, also co-authored by Johnson, which found that helping co-workers can wear you out and seriously hurt your job performance.
"Helping co-workers can be draining for the helpers, especially for employees who help a lot," says Johnson in the Journal of Applied Psychology.
The draining effects of helping others out are even worse for employees who are motivated by assisting others. "When these folks are asked for help, they feel a strong obligation to provide help, which can be especially taxing," says the co-author.
The 2016 findings suggest that employees should "exercise caution when agreeing to help" because doing so may leave them "depleted and less effective at work."
When employees find themselves having to help out frequently on a given day, they should try to bolster their energy by taking breaks, naps and stimulants like caffeine, according to the study.
Researchers also suggest that people who often ask for help curtail this habit and realize how detrimental it can be for the "helper."
The findings do not suggest that people shouldn't assist their colleagues. Rather, the workers should show discretion, especially early in the morning when they're tired or fatigued.
"This is not to say that co-workers should avoid seeking help," says the study, "but that they ought to consider the magnitude and solvability of the issue before doing so and avoid continually seeking help from the same person."
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