在同位式膝盖延伸过程中,CO2平衡和力输出特征的干扰之间的关系
Takahiro Yunoki1, Kejun Zang1, Kei Hatano2
1Department of Health and Physical Education, Graduate School of Education, Hokkaido University, Sapporo, Japan.
Respiratory physiology & neurobiology
|July 19, 2023
概括
改变的二氧化碳 (CO2) 恒温会影响肌肉的力量输出. 超 (高二氧化碳) 改善了力的一致性,而低 (低二氧化碳) 和正常的二氧化碳水平导致持续收缩期间的力下降.
科学领域:
- 生理学 生理学 生理学
- 运动生理学 运动生理学
- 呼吸系统生理学 呼吸系统生理学
背景情况:
- 维持二氧化碳 (CO2) 稳态对于生理功能至关重要.
- 以前的研究已经探讨了二氧化碳对各种身体系统的影响,但它对骨肌肉力输出特征的具体影响仍然不太了解.
- 了解这些影响对于从体育科学到临床康复等领域至关重要.
研究的目的:
- 为了研究二氧化碳稳态的干扰,特别是高头和低头,如何影响在同位数收缩期间下肢肌肉的力输出特征.
- 要确定这些影响是否独立于呼吸模式变量,如频率和潮体积.
主要方法:
- 在三个条件下,参与者在30%的最大自愿收缩 (MVC) 时进行了对称膝盖延伸试验:normocapnia (NORM), hypercapnia (HYPER) 和 hypocapnia (HYPO).
- 呼吸频率和潮体积被控制并与条件相匹配.
- 测量包括持续收缩期间的力变化系数 (Fcv) 和试验前后的MVC.
主要成果:
- 强力变化系数 (Fcv) 在高头 (HYPER) 条件下明显低于低头 (HYPO) 条件下,表明更一致的输出力.
- 在超的条件下,较高的末端潮CO2部分压力与增加的Fcv正相关.
- 在normocapnia和hypocapnia的试验中,最大自愿收缩 (MVC) 显著下降,但在hypercapnia中保持稳定.
结论:
- 二氧化碳稳态的干扰显著改变下肢肌肉的力输出特征.
- 超似乎增强了力输出稳定性,而低可能会损害它.
- 观察到的二氧化碳平衡对肌肉力量的影响独立于受控呼吸模式变量.
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