Once Again… Re-revised Science Fair Project? Please Help?

You may think I put this question in the wrong section, but no one has answered it yet. I want to test sleep deprivation versus bone health, but I wouldn’t know how to test it. I mean, I could have people record in their diaries the amount of sleep they got, but I wouldn’t know how to show how the bones change over time. If that is impossible, is there an experiment that I could create using the idea of how astronauts get a lot of bone fractures and osteoporosis and factors that could improve it before going into space where there is zero gravity? Could I use a skeletal structures and have one that did not have a lot of exercise in a lifetime and another structure that did and create a fake zero gravity to test the results? All I know that my project must contribute to humanity and it can’t be that easy…. thank you so much. I need constructive criticism Any ideas are helpful.