Fatigue responses during repeated sprints matched for initial mechanical output
Fatigue responses during repeated sprints matched for initial mechanical output
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DOI：
10.1249/mss.0b013e31815669dc
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发表时间：
2007-12-01
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影响因子：
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通讯作者：
Bishop, David
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文献类型：
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作者：
Mendez-Villanueva, Alberto;Hamer, Peter;Bishop, David
Mendez-Villanueva，A.，P.Hamer和D.Bishop。重复冲刺时的疲劳反应与初始机械输出相匹配。地中海医院。SCI。《体育运动》，第39卷，第12期，第2219-2225页，2007年。目的：比较在非疲劳和疲劳状态下两组初始机械输出相匹配的重复自行车短跑过程中的肌肉疲劳性。方法：8名青年男子在自行车测功机上进行10，6-S全力性短跑，中间穿插恢复30名S，被动恢复6分钟后，再进行5次6-S短跑，中间穿插30名S恢复。结果：在总功的基础上，短跑11跑成绩(79.8+/-4.8J·kg(-1))与短跑4级成绩(80.3+/-5.3J·kg(-1))差异无统计学意义；第4短跑后的5个短跑阶段(即第4至第8短跑阶段)的TW平均下降14.5%(P<；0.00 1)，显著低于第11至15短跑阶段的TW(20.3%；P<；0.05)。尽管短跑4和11的TW值没有显著差异，但在短跑11中记录的肌电(即均方根)信号的幅度(0.398+/-0.03V)比短跑4(0.452+/-0.02V)低12.0%(P<；0.05)。而短跑4次(85.5+/-5.5 Hz)和11次(89.3+/-7.2 Hz)记录到的肌电中位数频率(Mf)无显著差异(P=0.33)。然而，两组短跑的肌电活动(即RMS和MF)的下降速度是相似的。结论：这些发现表明，无论最初的机械输出量如何，先前的疲劳重复冲刺运动，然后是休息时间，在随后的重复冲刺运动中会导致更大的疲劳性，并且这些变化与急性神经肌肉调节有关。
MENDEZ-VILLANUEVA, A., P. HAMER, and D. BISHOP. Fatigue Responses during Repeated Sprints Matched for Initial Mechanical Output. Med. Sci. Sports Exerc., Vol. 39, No. 12, pp. 2219-2225,2007. Purpose: To compare muscle fatigability during two sets of repeated cycling sprints matched for initial mechanical output in a nonfatigued and fatigued state. Methods: Eight young men performed 10, 6-s all-out sprints on a cycle ergometer interspersed with 30 s of recovery, followed, after 6 min of passive recovery, by five 6-s sprints, again interspersed by 30 s of recovery, Results: On the basis of total work (TW), performance in sprint 11 (79.8 +/- 4.8 J.kg(-1)) was not significantly different to performance in sprint 4 (80.3 +/- 5.3 J.kg(-1); P = 0.81). The decrease in TW for the five sprints after sprint 4 (i.e., sprints 4 to 8) averaged 14.5% (P < 0.00 1), which was significantly less than the decrement in TW from sprints 11 to 15 (20.3%; P < 0.05). Despite no significant differences in TW values achieved in sprints 4 and 11, the amplitude of the electromyogram (EMG) signal (i.e., root mean square (RMS)) recorded during sprint 11 (0.398 +/- 0.03 V) was 12.0% lower (P < 0.05) than in sprint 4 (0.452 +/- 0.02 V). In contrast, values of EMG median frequency (MF) recorded during sprint 4 (85.5 +/- 5.5 Hz) and 11 (89.3 +/- 7.2 Hz) were not significantly different (P = 0.33). However, the rate of decrease in EMG activity (i.e., RMS and MF) was similar for the two set of sprints. Conclusions: These findings suggest that previous fatiguing repeated-sprint exercise, followed by a rest period, induces greater fatigability during subsequent repeated-sprint exercise, regardless of the initial mechanical output, and that these changes are associated with acute neuromuscular adjustments.