The Afterburn Effect: What You Need to Know

The promise almost seems too good to be true: If I put in the work and push myself during a workout, then I could keep burning calories for hours after it’s done? That means that after my Saturday morning sweat session, my body stays in fat-burning mode while I head out to a boozy brunch or kick back on the couch with some Netflix and a snack? Sign me up.

Known as the afterburn effect, this process is said to rev up your metabolism, helping your body burn calories for hours after you exercise. It’s a theory many High Intensity Interval Training gyms and personal trainers tout as one of the biggest benefits of their grueling workouts—promising you’ll reap the rewards of their one-hour session until the next day. But are these benefits too good to be true?

The theory makes sense on the surface. Like after revving up a car’s engine it stays warm for a while, right? But the science is a bit more varied. And like anything associated with health or losing weight, it seems like there’s a fair amount of hyperbole built into the hype. In fact, a growing body of evidence suggests that the afterburn effect, while beneficial, might not be as effective as once thought for burning fat.