How about working out in centrifuges for one hour a day at ... 0.5 G? (2001, here we come!) This should be testable on Earth with people kept in bed 23 h/day a

How about working out in centrifuges for one hour a day at ... 0.5 G? (2001, here we come!) This should be testable on Earth with people kept in bed 23 h/day and mild exercise. (It is like quite a few coding people's lifestyle.)