Fatigue from high- and low-frequency muscle stimulation: contractile and biochemical alterations.
Fatigue from high- and low-frequency muscle stimulation: contractile and biochemical alterations.
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高频和低频肌肉刺激引起的疲劳：收缩和生化改变。
DOI：
10.1152/jappl.1987.62.5.2075
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Fitts,RH
中科院分区：
文献类型：
--
作者：
Metzger,JM;Fitts,RH
本研究探讨了高（75 Hz，1分钟）和低（5 Hz，1.5分钟）频率刺激对膈肌收缩和生化特性的影响。在高频和低频刺激后，张力分别降低至初始值的21 +/- 1和54 +/- 2%（SE）。在从高频刺激恢复0、0.25、1和2分钟后，5 Hz引起比75 Hz刺激更多的力（表示为初始张力的%）。对于75 Hz和5 Hz刺激，时间0恢复值分别为初始力的21 +/- 1和78 +/- 6%。1分钟的恢复，5 Hz刺激引起的力已恢复到疲劳前的值。相反，75 Hz刺激产生的力直到10-15分钟才完全恢复。低频刺激产生疲劳后，5 Hz刺激产生的力减少到初始张力的54 +/- 2%，该值显著低于75 Hz刺激引起的初始力的71 +/- 2%。在恢复的前15秒内，5 Hz刺激产生的力迅速增加（0秒时为54 +/- 2%，15秒时为70 +/- 2%），到5分钟时，5 Hz刺激产生的力显著大于75 Hz刺激产生的力（100 +/- 3 vs. 93 +/- 1%）。如前所述，在75 Hz的刺激力的生产没有完全恢复，直到10-15分钟。这两个疲劳协议产生了显着的等长收缩和一半的放松时间延长。磷酸肌酸（CP）浓度降低，肌肉乳酸增加，这两个疲劳协议。（250字处删节）
This study examined the effect of high- (75 Hz, 1 min) and low- (5 Hz, 1.5 min) frequency stimulation on contractile and biochemical properties of the diaphragm. Tension was reduced to 21 +/- 1 and 54 +/- 2% (SE) of the initial value after high- and low-frequency stimulation, respectively. After 0, 0.25, 1, and 2 min of recovery from high-frequency stimulation, 5 Hz elicited more force (expressed as % of initial tension) than 75-Hz stimulation. Time 0 recovery values were 21 +/- 1 and 78 +/- 6% of the initial force for 75- and 5-Hz stimulation, respectively. By 1 min of recovery, force elicited by 5-Hz stimulation had returned to the prefatigue value. In contrast, force production with 75-Hz stimulation did not full recover until 10–15 min. After fatigue produced by low-frequency stimulation, force production with 5-Hz stimulation was reduced to 54 +/- 2% of the initial tension, a value significantly lower than the 71 +/- 2% of initial force elicited by 75-Hz stimulation. Force production with 5-Hz stimulation increased rapidly in the first 15 s of recovery (54 +/- 2% at 0 and 70 +/- 2% at 15 s) and by 5 min was significantly greater than the force elicited by 75-Hz stimulation (100 +/- 3 vs. 93 +/- 1%). As before, force production at 75-Hz stimulation did not fully recover until 10–15 min. Both fatigue protocols produced a significant prolongation in isometric twitch contraction and one-half relaxation times. Creatine phosphate (CP) concentration was reduced and muscle lactate increased by both fatigue protocols.(ABSTRACT TRUNCATED AT 250 WORDS)