Moving around, even if you're not breaking into a sweat, gives your mind a break from your current task, helps with circulation, facilitates the drawing of glucose into your cells so that it can be used as energy (the same thing insulin does) and decreases levels of the inflammatory mediator c-reactive protein which can damage your heart and lead to heart disease. Additionally, if you had been munching away at your desk, taking a break to walk to the water cooler for a refreshment or chat with a co-worker may give your hands and mouth something else to do other than eating.
According to Dr. Genevieve Healy from the University of Queensland, who led the study, "the potential adverse health impact of prolonged sitting (which is something that we do on average for more than half of our day), is only just being realised". She went on to say that the findings of this current research, which showed that even making small changes can be beneficial to your health and can assist with weight loss, "are likely to have implications for settings where prolonged sitting is widespread, such as in offices." Her advice? "Stand up, move more, more often". Hey - Isn't it break time right about now?