If you want to get more done during your day, stop multitasking. It’s that simple.

“Psychologists who study what happens to cognition (mental processes) when people try to perform more than one task at a time have found that the mind and brain were not designed for heavy-duty multitasking,” according to the American Psychological Association.

The APA says multitasking can take place when someone tries to perform two tasks at the same time, switch from one task to another, or perform two or more tasks in rapid succession.

For decades, studies have shown that you aren’t saving time by multitasking. But most of us still try to toggle between projects.

“Although switch costs may be relatively small, sometimes just a few tenths of a second per switch, they can add up to large amounts when people switch repeatedly back and forth between tasks. Thus, multitasking may seem efficient on the surface but may actually take more time in the end and involve more error,” the APA says.

Instead, try blocking off chunks of time to focus on a single project. When you finish one task, move on to the next.

You can also try finishing easy tasks quickly to get them off your plate. Build in time during your day for urgent assignments and some flexibility in case tasks take longer than expected.

What about emails and messages? You don’t need to check email constantly throughout the day—try checking it two or three times a day. There are phone apps and computer platforms that can help you stay focused by eliminating distractions.