In BJSM , Gabel and colleagues in their paper ‘Pre-flight Exercise and Bone Metabolism Predict Unloading-Induced Bone Loss due to Spaceflight’ study skeletal health in a unique population of ‘occupational athletes’: astronauts.1 Astronauts frequently experience cardiovascular deconditioning, immune suppression, balance disorders, strength deficits and bone loss as a result of space travel.2 After more than 50 years of space missions, various contributors to bone loss in astronauts have been postulated—microgravity, radiation, stress, metabolic disruption and altered calcium homeostasis all likely play a role.3 Using high-resolution three-dimensional imaging (HR-pQCT), Gabel et al report declines in bone mineral density (BMD), bone microstructure and strength at the distal tibia, although minimal changes at the distal radius.1 Their findings are broadly similar to prior reports, revealing an average rate of bone decline nearly 10-fold higher than that seen in postmenopausal women, although with remarkable interindividual variability seen in these astronauts.4 Notably, their analyses bring several new insights to our understanding of unloading-induced bone loss. For spaceflight of 3.5–7 months, mission time predicted tibial BMD loss linearly, with accelerated trabecular bone loss in longer flights.1 A …

中文翻译：

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火箭科学：太空飞行可以告诉我们关于地球骨骼健康的信息

1 他们的研究结果与之前的报告大体相似，显示平均骨质下降率比绝经后女性高出近 10 倍，尽管在这些宇航员中发现了显着的个体差异。 4 值得注意的是，他们的分析为我们带来了一些新的见解了解卸载引起的骨质流失。对于 3.5-7 个月的太空飞行，任务时间线性预测胫骨 BMD 损失，在更长的飞行中加速小梁骨损失。1 A …