概括
β-上腺素阻塞减弱了运动条件的改善,改善了心脏和血液循环,但没有骨肌肉的适应. 心脏选择性在有氧训练期间没有改变这些效应.
科学领域:
- 运动生理学 运动生理学
- 心血管适应的情况.
- 骨肌肉生理学 骨肌肉生理学
背景情况:
- 运动调节通过心脏,血液循环和骨肌肉的适应来提高运动能力.
- 在这些适应中,β-上腺素刺激的具体作用尚不清楚.
研究的目的:
- 研究β1-选择性和非选择性β-上腺素阻断对炼条件的影响.
- 为了确定心脏选择性是否会影响对有氧训练的适应.
主要方法:
- 24名健康的久坐不动的男性接受了为期6周的有氧训练计划.
- 参与者接受了安慰剂,阿诺洛尔 (β1选择性) 或纳多洛尔 (非选择性),并在训练前和训练后进行了测试.
- 测量包括最大氧气摄入量 (VO2max),运动持续时间,氧气脉冲,心率,血压,腿部血流和肌肉活检分析.
主要成果:
- 与安慰剂相比,β-上腺素阻塞 (atenolol和nadolol) 减弱了VO2max和运动持续时间的改善.
- 心脏和外周血管适应受β-上腺体阻塞影响.
- 骨肌肉的适应,包括毛细血管供应和氧化酶活性,不受β-上腺素阻塞的影响.
- 心脏选择性似乎没有改变β-上腺体阻塞的效果.
结论:
- 在有氧训练期间,β-上腺素阻塞会损害心脏和外周血管的适应性.
- 骨肌肉适应运动条件的适应性不受β-上腺体阻塞的显著影响.
- 心脏选择性在修改β-上腺素阻断对运动调节的影响方面并不至关重要.
相关概念视频
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Isoprenaline > Adrenaline > Noradrenaline
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01:27Adrenergic Antagonists: Pharmacological Actions of β-Receptor Blockers
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