国际空间站上男性宇航员的基质代谢:ENERGY研究
Elisa Le Roux1, Alexandre Zahariev1, Isabelle Chery1
1Université de Strasbourg, CNRS, IPHC UMR 7178, Strasbourg, F-67000, France.
NPJ microgravity
|March 28, 2024
概括
国际空间站的宇航员在禁食期间转向使用碳水化合物而不是脂肪,这主要是由于饮食变化. 饭后的燃料使用变化取决于身体成分和体力活动水平.
科学领域:
- 空间生理学空间生理学
- 人类新陈代谢的人类新陈代谢.
- 营养科学 营养科学
背景情况:
- 床上休息改变了对碳水化合物的燃料选择,影响了宇航员的健康和性能.
- 了解长期太空飞行期间的代谢变化对于机组人员的福祉至关重要.
研究的目的:
- 为了调查长期国际空间站 (ISS) 任务后宇航员的燃料利用转变.
- 探索燃料选择,饮食,体力活动和身体组成在空间中的变化之间的相关性.
主要方法:
- 在国际空间站任务前和期间,间接热量计测量了11名男性宇航员的呼吸系数 (RQ),碳水化合物和脂肪氧化.
- 评估了饮食摄入量 (食物系数 - FQ),身体成分 (脂肪质量 - FM,无脂肪质量 - FFM) 和体力活动 (PA).
- 餐后基质的使用是使用营养氧化和ΔRQ (饭后RQ的变化) 来分析的.
主要成果:
- 太空飞行增加了禁食RQ和碳水化合物氧化,同时降低了禁食脂质氧化.
- 增加的FQ表明任务期间的饮食修改.
- 禁食基质氧化转移与飞行中的饮食变化 (FQ) 相相关.
- 餐后基质使用 (营养氧化,ΔRQ) 平均没有显著改变.
- 饭后脂质和碳水化合物氧化变化的变化与FFM,FM和有氧运动的变化有关.
结论:
- 在太空飞行期间观察到的禁食基质氧化转变可能是由饮食修改驱动的.
- 餐后燃料选择的个体差异与宇航员体质组成和体力活动水平的变化有关.
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