1. Walk or bike to work. If you are riding in a public transport, get off one stop earlier, or park your personal vehicle a little away from office.
2. Stand rather than sit. You will burn more calories standing rather than sitting. Pace continuously while talking on the phone.
3. During tea/lunch break, take a brisk walk or do some gentle stretching.
4. If while travelling for work, you are stuck at an airport, take a brisk walk. In the hotel before meetings, try to do a small work-out in the hotel gym or walk briskly around in the hotel.