两种强度疲劳性运动引起血K^+和血PH值变化及其对活动肌和非活动肌表面肌电图的影响  

Change of Plasma K^+ and pH Induced by Two Fatiguing Exercises with Different Intensity and Their Effects on Surface EMG of Active and Inactive Muscles

作　　者：何伟 

出　　处：《北京体育大学学报》1994年第S2期37-42,共6页Journal of Beijing Sport University

摘　　要：为探索K+、H+与肌肉疲劳和肌电变化的关系，检测了同一批受试者200W和120W蹬功率车至疲劳前和运动后即刻、5min，10min、20min时，血K+、血PH值以及活动肌和非活动肌定量负荷等长收缩10s的EMG。结果表明，两次运动后血K+和AM－MPF、明显改变（P＜0．001），二者高度负相关，并在20min时基本恢复。200W运动后20min内血PH值一直明显低于安静值（P＜0．001），但在120W运动后无变化，并与肌电无相关关系。120W运动后20min内的IM－IEMG明显低于安静值（P＜0．05）。结果表明，细胞外高K+是肌肉疲劳和AM－MPF下降的主要因素之一，并可能也是IM-IEMG下降的原因之一。H+不是疲劳形成的主在原因，并对肌电无直接影响。This study was undertaken to explore the relationship between plasma K+, H+ and muscle fatigue as well as electromyogram changes. Fourteen male students performed two exercise tests of different intensity (respectively 200 watts and 120 watts)to fatigue on a cycle ergometer. The plasma K+, pH and EMG of active and inactive muscles during 10 sec. isometric contraction with fixed load were measured before exercise and at 0, 5, 10, 20 minutes after exercise. Both plasma K+ and MPF of the active muscles changed significantly (p<0. 001) after exercise,but recovered in 20 minutes and were highly negatively interrelated. Plasma PH at 20 minutes after 200 watts exercise was significantly lower than at rest, but did not change after 120 watts exercise, and no interrelation was found between pH and EMG. IEMG of inactive muscles at 20 minutes after 120 watts exercise was significantly iower than at rest (p<0. 05). The results showed that high extracellular K+ concentration was one main factor inducing fatigue and MPF decrease of active muscles, but H+ was not a main factor for fatigue and of no direct effect on EMG.

关 键 词：肌肉疲劳 血K^+ 血PH值 活动肌EMG(简写AM-EMG) 非活动肌EMG(简写IM-EMG) 

分 类 号：G804[文化科学—运动人体科学]