在南极探险后的骨平衡
Charlotte V Coombs1, Stefano Capella2, Natalie Taylor3
1Army Health and Performance Research, Army Headquarters, Andover, United Kingdom.
Journal of applied physiology (Bethesda, Md. : 1985)
|November 10, 2025
概括
极端的探险会由于能量不足而导致骨密度下降. 虽然骨平衡标志物表现出个体的变化,但整体群体水平保持稳定,这表明尽管累积骨损失,流的快速正常化.
科学领域:
- 人类生理学 人类生理学
- 骨的新陈代谢 骨的新陈代谢
- 环境的极端情况.
背景情况:
- 远征会导致大量的运动量和能量赤字,可能会影响骨矿物质密度和平衡.
- 面积骨矿物质密度 (aBMD) 是骨健康和平衡的关键指标.
研究的目的:
- 为了研究长时间穿越南极对骨矿物质密度 (aBMD) 和骨平衡的影响.
- 为了评估同位素比率 (δ44/42Ca) 的变化,作为极端环境压力期间骨平衡的标志物.
主要方法:
- 九名参与者进行了一次911公里长的南极穿越,在47天内拖走85公斤的雪.
- 全身aBMD使用DXA测量,测量前后.
- 在多个时间点收集尿液样本以测量同位素比率 (δ44/42Ca).
- 血液样本分析了关键激素,包括副甲状腺激素,维生素D,生殖激素和甲状腺激素.
主要成果:
- 在不同地区观察到体重 (-3.3%),身体脂肪百分比 (-21.4%) 和aBMD (-1.3%至-12.1%) 显著下降.
- 虽然小组级尿液 δ44/42Ca 没有显著变化,但观察到相当大的个体间反应变化.
- 甲状腺刺激激素和总T3水平在远征后增加,而大多数生殖激素和其他测量参数保持稳定.
结论:
- 观察到的aBMD的下降很可能归因于远征期间经历的长期能源赤字.
- 尽管减少了BMD,但团队级骨平衡没有变化,这可能是由于 δ44/42Ca.追踪的短期流的快速正常化.
- 这项研究强调了极端环境,能量平衡和骨健康之间的复杂相互作用,利用一种新的同位素方法来评估动态.
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