The internet and email have made it infinitely easier for humans to stay in touch, but for employees trying to maintain a healthy work-life balance, that may not always be a good thing. According to new research that will be presented at the Academy of Management's annual meeting, the expectation that employees should respond to emails outside of work hours may cause exhaustion and burnout.

Researchers at Lehigh University, Virginia Tech, and Colorado State University analyzed data from 385 surveys completed by professionals in a range of fields. Participants answered questions about the amount of time spent on email outside of work, their emotional exhaustion levels, perceptions of work-family balance, and their perceived psychological detachment from work during off-hours. In general, researchers found that after-hours emails were a significant job stressor for volunteers, with an impact similar to high workload and interpersonal conflict.

Researchers also discovered that it wasn’t just the amount of time spent responding to emails outside of work that was stressful—the mere anticipation of after-hours emails caused stress. That is, just knowing that a work-related email could be on its way contributed to emotional exhaustion.

“Email is notoriously known to be the impediment of the recovery process,” the researchers explain. “Its accessibility contributes to experience of work overload since it allows employees to engage in work as if they never left the workspace, and at the same time, inhibits their ability to psychologically detach from work-related issues via continuous connectivity.”

While it may be impossible for some of us to completely ignore our emails outside of work, researchers say it’s important to find some time to fully disconnect, especially if you’re feeling stressed. They also suggest that businesses implement email-free days or rotating email shifts to ensure employees are able to take the occasional vacation from their work emails.