Matsuura Ryouta, Ogata Hisayoshi, Yunoki Takahiro, Arimitsu Takuma, Yano Tokuo
Laboratory of Exercise Physiology, Graduate School of Education, Hokkaido University, Sapporo, Japan.
J Physiol Anthropol. 2006 Jul;25(4):267-73. doi: 10.2114/jpa2.25.267.
The purpose of this study was to determine whether neuromuscular activation is affected by blood lactate concentration (La) and the level of oxygen uptake immediately before a cycling sprint (preVO(2)). The tests consisted of ten repeated cycling sprints for 10 sec with 35-sec (RCS(35)) and 350-sec recovery periods (RCS(350)). Peak power output (PPO) was not significantly changed despite an increase in La concentration up to 12 mmol/L in RCS(350). Mean power frequency (MPF) of the power spectrum calculated from a surface electromyogram on the vastus lateralis showed a significantly higher level in RCS(350). In RCS(35), preVO(2) level and La were higher than those in RCS(350) in the initial stage of the RCS and in the last half of the RCS, respectively. Thus, neuromuscular activation during exercise with maximal effort is affected by blood lactate concentration and the level of oxygen uptake immediately before exercise, suggesting a cyclic system between muscle recruitment pattern and muscle metabolites.
本研究的目的是确定在自行车冲刺前即刻，神经肌肉激活是否受血乳酸浓度（La）和摄氧量水平（preVO₂）的影响。测试包括进行10次重复的10秒自行车冲刺，恢复期分别为35秒（RCS(35)）和350秒（RCS(350)）。尽管在RCS(350)中La浓度增加至12 mmol/L，但峰值功率输出（PPO）无显著变化。从股外侧肌表面肌电图计算得到的功率谱平均功率频率（MPF）在RCS(350)中显著更高。在RCS(35)中，RCS初始阶段的preVO₂水平和RCS后半段的La分别高于RCS(350)中的相应水平。因此，竭尽全力运动期间的神经肌肉激活受血乳酸浓度和运动前即刻的摄氧量水平影响，提示肌肉募集模式与肌肉代谢物之间存在循环系统。
