Ask HN: Travel a lot? How do you keep fit?

I'm not exactly on the road a lot, but I do know a few people that are. I do, however, have very little time or space for exercise. I also do not have or want to carry heavy and expensive equipment around me the whole time. If you're a digital nomad, on the road a lot, or generally have limited time, space and budget, how do you keep your body healthy?