Which is better for you: working out in the morning or working out in the evening?

It’s a question that has nagged at the minds of many fitness enthusiasts at one time or another. Time magazine reporter Jamie Ducharme recently asked Anthony Hackney, a professor of sports science at the University of North Carolina at Chapel Hill, for an answer and got one. Although Hackney stresses that consistency is by far the most important element of any exercise regimen, he gives morning workouts the edge.

“In the early morning hours, you have a hormonal profile that would predispose you to better metabolism of fat,” Hackney says. In plain English: You’ll burn more calories working out in the morning than in the afternoon or evening.

But if you’re a night owl rather than an early bird, no sweat. Hackney says that in the end, any hour of the day or night is a good time to exercise.