Do you take advantage of an early start on the day or try to catch some more sleep?

The best answer depends on a few factors, experts tell Fortune, but generally leans toward heading back to bed. That’s because sleep has restorative properties and impacts multiple body systems.

The first question to ask yourself: whether or not you’ve gotten the recommended seven to nine hours of shut-eye. That’s according to Joachim Behar, a sleep researcher and the head of the Artificial Intelligence in Medicine Laboratory at the Technion – Israel Institute of Technology in Haifa, Israel.

Keep reading at fortune.com.