[sandworm101]

My GP is big on bones, specializing in old people. He helped develop some of the fancy bone scanners decades ago. He told me that astronaut bone loss is a solved problem, that if they want too they can keep bones strong for a year or more. He was of the opinion that when astros come back with reduced bone it is because they have been part of a study. The goal isn't to save all the bone, but to study exactly how little exercise is needed to achieve satisfactory results.

[Neeek]

That makes sense, easy to forget they are sometimes called on to be highly skilled/paid lab rats at times :)