People who trained vigorously for 45 minutes at a level of effort that increased body temperature, raised heart rate, and induced sweating burned an average of 190 extra calories in the 14 hours following the training session.
They also burned about 590 total calories in the exercise session itself. This contrasts with low intensity exercise, which does not increase caloric expenditure in the hours following exercise sessions.
As this article points out, if you need mental refreshment, a coffee break will probably backfire, but a growing body of research shows that making contact with live plants and animals, even if vicarious (photos of forests) is more effective than other diversions. A little time enjoying the sights and sounds of nature also has proven successful at relieving depression and anxiety and boosting cognitive performance.