Credit: Kim Ratliff, Augusta University AUGUSTA, Ga. (Feb.18, 2021) - Extended time in space weakens astronauts' bones, so scientists are working to better understand how bone senses and responds to the usual forces placed upon it with the goal of keeping their bones strong. The skeleton's ability to adapt to mechanical loading -- the forces put on bone by both gravity and muscle in response to movement -- is critical to bone health, and circumstances like spaceflight or a spinal cord injury can interfere, says Dr. Meghan E. McGee-Lawrence, biomedical engineer in the Department of Cellular Biology and Anatomy at the Medical College of Georgia.