Lead researcher Adrian Taylor of the University of Exeter in England said the study involved 78 regular chocolate-eaters invited to enter a simulated work environment, after two days abstinence from chocolate snacking.
Two groups were asked to take a brisk, 15-minute walk on a treadmill and were then given work to complete at a desk. One group was given an easy, low-stress task, while the other was asked to complete a more demanding job.
The other two groups were asked to have a rest before completing the same tasks as the first two groups. Again, half were given an easier task and the remainder a more challenging one, Taylor said.
Chocolate was available in a bowl on the desk for all participants as they carried out their work.
The study, published in the journal Appetite, found those who exercised before working consumed on average half the amount of chocolate as the others -- one small "treat size" or "fun size" chocolate bar instead of two.
"We often feel that these snacks give us an energy boost, or help us deal with the stress of our jobs, including boredom," Taylor said in a statement. "People often find it difficult to cut down on their daily treats but this study shows that by taking a short walk, they are able to regulate their intake by half."