碳水化合物可用性对最大乳酸稳定状态下骑自行车耐力的影响
Colton P Quinn1, Rachel M McDougall1, Saied Jalal Aboodarda1
1Faculty of Kinesiology, Human Performance Lab, University of Calgary, Alberta, Canada.
概括
在最大乳酸稳定状态下,碳水化合物负载并没有改善循环时间到任务失败. 然而,之前的强度炼显著降低了耐力,即使补充碳水化合物,强调在MLSS测试之前避免大幅改变饮食和炼的重要性.
科学领域:
- 运动生理学 运动生理学
- 运动营养 运动营养
背景情况:
- 碳水化合物可用性对于耐力表现至关重要.
- 它对最大乳酸稳定状态 (MLSS) 的任务失败时间 (TTF) 的影响仍未得到充分研究.
研究的目的:
- 调查碳水化合物 (CHO) 可用性对TTF和MLSS运动期间生理反应的影响.
- 为了确定CHO加载是否提高了MLSS的性能.
主要方法:
- 这是一项双盲,安慰剂控制的研究,共10名参与者.
- 四个条件:CHO负载 (7g/kg) 或安慰剂,先前有或没有消耗糖原的运动 (EX).
- 测量包括坡道增量测试,MLSS确定,以及在循环人体计上进行TTF试验.
主要成果:
- 在没有先前的练习 (REST条件) 的情况下,CHO加载并没有改善MLSS的TTF.
- 之前的强度运动 (EX条件) 与REST相比,TTF减少了50%左右.
- 在EX条件下服用CHO补充剂,与安慰剂相比,TTF增加了90% (EXCHO与EXPLA).
- 在持续30分钟的条件下,血液中乳酸盐度稳定.
结论:
- 运动前的CHO补充剂不会在MLSS中增强TTF.
- 最近的强度运动显著降低了MLSS的TTF,即使服用CHO补充剂.
- 在MLSS确定之前,避免极端的饮食变化和剧烈的运动,以确保准确的结果.
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