My instruction time has specified breaks, but often the students do not take them, even if I urge them to. This results in them working and listening to my instruction while they are overdone. I tell them this is a marathon, not a sprint, and they will have the rest of their lives to sit in a chair in front of a keyboard, but they do not take the break, or they get a sip of water in the hallway and sit back down. This is impeding their learning and making them unhealthy ("Sitting is the new smoking", right?).
Have you found any effective ways to get students out of the chair to take their full breaks, other than having them take up smoking (thus defeating the purpose) or yelling Fire?