Data gathered from space missions and ground-based research simulating weightlessness has shown that exposure to microgravity leads to significant changes in human skeletal structure. Loss of bone mass and complex changes in mineral balance and content are associated with some of the most profound physiological alterations resulting from space flight. Characterizing the mechanisms of these changes, and developing countermeasures to them, is critical to long-term habitation of space on the International Space Station and during extended missions.
The Bone and Mineral Laboratory provides comprehensive bone mineral, muscle, and body composition testing and evaluation. Testing of ISS astronaut and cosmonaut crewmembers occur in the USA and Russia. Skeletal health reports are provided to NASA and astronauts are followed long term to monitor changes in skeletal health during crew career and to ensure that medical standards are met for crew re-flight certification. This laboratory also provides support in developing ground experiments including the testing during flight and ground-analog studies (e.g., bed-rest studies).
Ground-based and in-flight research is conducted to determine the effects of real or simulated space flight on the musculoskeletal system and to develop countermeasures. Changes in bone mineral density and quality, decreases in muscle volume, and changes in the size and composition of intervertebral discs are measured. State of the art equipment and techniques, including bone densitometry, magnetic resonance imaging, quantitative computed tomography, and ultrasound/acoustic assessment of bone quality are all utilized within the Bone and Mineral Laboratory.
Promising countermeasures to minimize bone loss include the use of medications and the addition of resistive exercise (weight lifting). Current research is focusing on both individual and combination therapeutic regimens.