长时间运动期间的中风体积反应取决于左心室的填充:来自β阻塞研究的证据
Fabio Giuseppe Laginestra1,2, Ole Kristian Berg3, Stian Kwak Nyberg4
1Department of Circulation and Medical Imaging, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.
概括
预防心率偏移在长时间炼期间与β-阻塞剂通过增加终端透缩体积改善了中风体积. 这表明填充时间和左心室负载条件对于中风体积调节至关重要.
科学领域:
- 运动生理学 运动生理学
- 心血管生理学心血管生理学
- 药理学 药理学是指药理学的学科.
背景情况:
- 长时间的中等强度运动通常会导致心率 (HR) 增加,这种现象被称为HR漂移.
- 这种HR偏移可能会对中风体积 (SV) 和心脏输出产生负面影响.
- 关联HR偏移到SV变化的潜在机制,特别是左心室功能,需要进一步调查.
研究的目的:
- 为了研究心血管漂移在长时间运动期间对左心室体积和中风体积的影响.
- 为了确定是否防止HR漂移改变左心室末端透缩体积 (EDV) 和末端透缩体积 (ESV),从而影响SV.
主要方法:
- 十三名健康的年轻男性在57%的最大氧气消耗 (V·o2max) 时进行了两次60分钟的骑自行车训练.
- 参与者接受了安慰剂 (CON) 或低剂量的β-1抑制剂 (BB) 来抑制HR漂移.
- 心声学被用来测量HR,EDV和ESV,同时监测其他生理参数.
主要成果:
- 贝塔抑制剂的使用成功地防止了在安慰剂条件下观察到的典型HR漂移.
- 冲击体积 (SV) 在BB组显著增加了13%,而在CON组保持不变.
- 在BB组中,这种SV的增加与终端透缩体积 (EDV) 的4%的增加有关,这表明心室填充得到改善.
结论:
- 在长时间炼期间阻断心率偏移会增加终端透静体积和中风体积.
- 这些发现凸显了填充时间和左心室负载条件在持续体力活动期间调节中风量方面的关键作用.
- 心血管漂移可能会损害心室填充,导致在耐力运动中减少中风体积.
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