Effects of arterial oxygen content on peripheral locomotor muscle fatigue
Effects of arterial oxygen content on peripheral locomotor muscle fatigue
复制标题
DOI：
10.1152/japplphysiol.01596.2005
复制
发表时间：
2006-07-01
影响因子：
3.3
通讯作者：
Dempsey, Jerome A.
中科院分区：
文献类型：
--
作者：
Amann, Markus;Romer, Lee M.;Dempsey, Jerome A.
在健康、训练有素的男性运动员中评估动脉氧含量（Ca-O2）对股四头肌疲劳的影响。在不同的日子里，八名参与者在固定工作负荷（314 +/- 13 W）下在自行车测力计上完成了三次恒定工作负荷试验。第一次试验是在受试者呼吸低氧气体混合物[吸入的O-2分数（FIO 2）= 0.15，Hb饱和度= 81.6%，Ca-O2 = 18.2 ml O-2/dl血液; Hypo]直到耗尽（4.5 +/- 0.4 min）时进行的。其余两项试验是随机的，时间与Hypo匹配。第二项和第三项试验分别在受试者呼吸常氧（FIO 2 = 0.21，Hb饱和度= 95.0%，Ca-O2 = 21.3 ml O-2/dl血液;正常）和高氧（FIO 2 = 1.0，Hb饱和度= 100%，Ca-O2 = 23.8 ml O-2/dl血液;高）气体混合物时进行。在运动前和运动后2.5分钟，通过磁股神经刺激（1-100 Hz）评估股四头肌疲劳。在整个运动过程中，股外侧肌的肌电活动由表面电极获得。运动后即刻，Hypo、Norm和Hyper的1-100 Hz范围内的平均力反应值较运动前值分别下降了-26 +/-2、-17 +/-2和-13 +/-2%（P < 0.01）;每种下降幅度都有显著差异（P < 0.05）。在整个运动过程中，Hypo、Norm和Hyper的综合肌电图分别显著增加23 +/- 3、10 +/- 1和6 +/- 1%（P < 0.01）;每种增量均显著不同（P < 0.05）。Hypo（-15 +/-2%）期间平均功率频率下降更多（P < 0.05）; Norm（-7 +/-1%）和Hyper（-6 +/-1%）之间的差异不显著（P = 0.32）。我们的结论是，三角洲Ca-O2在剧烈的全身运动在相同的工作量和持续时间影响运动肌肉疲劳的发展速度。
The effect of arterial O-2 content (Ca-O2) on quadriceps fatigue was assessed in healthy, trained male athletes. On separate days, eight participants completed three constant-workload trials on a bicycle ergometer at fixed workloads (314 +/- 13 W). The first trial was performed while the subjects breathed a hypoxic gas mixture [inspired O-2 fraction (FIO2) = 0.15, Hb saturation = 81.6%, Ca-O2 = 18.2 ml O-2/dl blood; Hypo] until exhaustion (4.5 +/- 0.4 min). The remaining two trials were randomized and time matched with Hypo. The second and third trials were performed while the subjects breathed a normoxic (FIO2 = 0.21, Hb saturation = 95.0%, Ca-O2 = 21.3 ml O-2/dl blood; Norm) and a hyperoxic (FIO2 = 1.0, Hb saturation = 100%, Ca-O2 = 23.8 ml O-2/dl blood; Hyper) gas mixture, respectively. Quadriceps muscle fatigue was assessed via magnetic femoral nerve stimulation (1-100 Hz) before and 2.5 min after exercise. Myoelectrical activity of the vastus lateralis was obtained from surface electrodes throughout exercise. Immediately after exercise, the mean force response across 1-100 Hz decreased from preexercise values (P < 0.01) by -26 +/- 2, -17 +/- 2, and -13 +/- 2% for Hypo, Norm, and Hyper, respectively; each of the decrements differed significantly (P < 0.05). Integrated electromyogram increased significantly throughout exercise (P < 0.01) by 23 +/- 3, 10 +/- 1, and 6 +/- 1% for Hypo, Norm, and Hyper, respectively; each of the increments differed significantly (P < 0.05). Mean power frequency fell more (P < 0.05) during Hypo (-15 +/- 2%); the difference between Norm (-7 +/- 1%) and Hyper (-6 +/- 1%) was not significant (P = 0.32). We conclude that Delta Ca-O2 during strenuous systemic exercise at equal workloads and durations affects the rate of locomotor muscle fatigue development.