G耐受性和血管交感反射反应受到重复长时间暴露于增强力场的影响
Ola Eiken1, Michail E Keramidas2, Antonis Elia2
1Joint Medical Division, Air Component Command, Swedish Armed Forces, Uppsala, Sweden.
概括
通过增加血管硬度,重复暴露于头到座位的G负荷改善了飞行员的快速G耐受性. 这种训练并没有增强整体的同情反应或巴罗反射灵敏度,但减少了前庭交感反射.
科学领域:
- 航空航天医学 航空航天医学
- 人体生理学 人体生理学
- 心血管生理学心血管生理学
背景情况:
- 对于战斗机飞行员来说,高G力耐受性至关重要.
- 了解适应性响应G负荷对于飞行安全和性能至关重要.
研究的目的:
- 为了研究重复的头到座位 (+Gz) G负荷暴露如何影响放松的+Gz容忍度.
- 为了检查对G-保护性交感反射压力反应的影响.
主要方法:
- 12名男性在5周内接受了15次40分钟+Gz暴露.
- 在训练前和训练后使用快速 (ROR) 和逐渐 (GOR) 发病率G暴露来评估耐受性.
- 心血管反应在+Gx暴露,静止挑战和带气质受体操纵期间被测量.
主要成果:
- G训练增加了17%的ROR+Gz耐受性 (P=0.04),但没有改变GOR+Gz耐受性或静态耐受性.
- Carotid baroreflex 灵敏度和操作压力范围保持不变.
- 对+Gx暴露的动脉压反应减少了 (P<0.001),这表明静脉交感反射变.
结论:
- 重复的+Gz暴露增加了对快速G发作的耐受性,这可能是由于局部血管适应,例如增加了毛囊前血管硬度.
- 总体而言,这种训练方案并没有改善血管交感反应和頸動脈巴洛反射功能.
- 这种训练可能会降低前庭交感反射响应能力.
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