Play basketball, football, baseball, tennis or badminton. Many doctors have recommended sports as an effective way to stay fit and healthy. Sports can also be done in moderation. Do not take it seriously. Shooting basketball with a friend is one moderate exercise that is also considered a sport.
If you still do not have exercises programs at work, then why not start it? You can talk to your boss about it and start with your colleagues. You do not only lose calories but it is also one good way to bond with them. This can be done 30 minutes, 3 times a week.