Jost P D
Hippokratia. 2008 Aug;12 Suppl 1(Suppl 1):37-40.
In a recent review on bed rest studies of the past 20 years, it was concluded that head-down bed rest has proved its usefulness as a reliable simulation model for most physiological effects of spaceflight. Much of this research has been conducted to find countermeasures against the negative effects, which are associated with gravitational unloading. There have been partial successes in the prevention of, for example muscle wasting, cardio-vascular deconditioning, adverse metabolic changes, and bone demineralization. Reviews refer to bone-related measurements of the U.S. and Russian space programmes, as well as data from bed rest analogues, and conclude that in spite of the wealth of knowledge obtained thus far, many questions remain regarding bone loss, bone recovery, and the factors affecting these skeletal processes. Bed rest research has also direct relevance for medical science on Earth. Valuable data on physiology and early reversible pathological changes that are associated with a sedentary lifestyle on Earth can be obtained. A good example is the conclusion from a metabolic protocol implemented during the 2001/2002 90-day ESA/CNES/NASDA male bed rest study. The results of that experiment on fatty acid oxidation suggest that Mediterranean diets should be recommended in recumbent patients. Some other unexpected results obtained during the ESA/NASA/CNES/CSA 60-day female bed rest study WISE-2005 may well prompt the development of a treatment for certain cardiac diseases. A nutritional supplement that was designed to alleviate skeletal muscle atrophy turned out to preserve cardiac muscle mass. In order to optimise bed rest research, a systematic and standardised approach will be beneficial. During the last years, serious efforts have been made towards such standardisation on an international level. It is expected that results from future studies, combined with in-flight validation, will provide the answers to many biomedical problems that currently limit safe long-duration human space exploration beyond lower earth orbit.
在最近一篇关于过去20年卧床休息研究的综述中，得出的结论是，头低位卧床休息已证明其作为模拟太空飞行大多数生理效应的可靠模型是有用的。这项研究大多是为了寻找对抗与重力卸载相关的负面影响的对策。在预防例如肌肉萎缩、心血管功能失调、不良代谢变化和骨质流失方面已取得部分成功。综述参考了美国和俄罗斯太空计划中与骨骼相关的测量数据，以及卧床休息模拟实验的数据，并得出结论，尽管迄今已获得大量知识，但关于骨质流失、骨质恢复以及影响这些骨骼过程的因素仍有许多问题。卧床休息研究对地球上的医学也有直接相关性。可以获得与地球上久坐不动的生活方式相关的生理学和早期可逆病理变化的宝贵数据。一个很好的例子是在2001/2002年欧洲航天局/法国国家空间研究中心/日本宇宙航空研究开发机构男性90天卧床休息研究期间实施的一项代谢方案得出的结论。该脂肪酸氧化实验的结果表明，对于卧床患者应推荐地中海饮食。在欧洲航天局/美国国家航空航天局/法国国家空间研究中心/加拿大航天局2005年WISE-60天女性卧床休息研究期间获得的一些其他意外结果很可能会促使开发出针对某些心脏病的治疗方法。一种旨在减轻骨骼肌萎缩的营养补充剂结果却能维持心肌质量。为了优化卧床休息研究，采用系统和标准化的方法将是有益的。在过去几年里，国际层面已为实现这种标准化做出了认真努力。预计未来研究的结果，结合飞行中的验证，将为目前限制安全进行低地球轨道以外的长期载人太空探索的许多生物医学问题提供答案。
