Farup J, Rahbek S K, Bjerre J, de Paoli F, Vissing K
Section for Sports Science, Department of Public Health, Aarhus University, Aarhus, Denmark.
Department of Biomedicine, Aarhus University, Aarhus, Denmark.
Scand J Med Sci Sports. 2016 May;26(5):498-506. doi: 10.1111/sms.12481. Epub 2015 May 6.
The present study investigated the changes in contractile rate of force development (RFD) and the neural drive following a single bout of eccentric exercise. Twenty-four subjects performed 15 × 10 maximal isokinetic eccentric knee extensor contractions. Prior to and at 24, 48, 72, 96, and 168 h during post-exercise recovery, isometric RFD (30, 50 100, and 200 ms), normalized RFD [1/6,1/2, and 2/3 of maximal voluntary contraction (MVC)] and rate of electromyography rise (RER; 30, 50, and 75 ms) were measured. RFD decreased by 28-42% peaking at 48 h (P < 0.01-P < 0.001) and remained depressed at 168 h (P < 0.05). Normalized RFD at 2/3 of MVC decreased by 22-39% (P < 0.01), peaked at 72 h and returned to baseline at 168 h. These changes in RFD were associated with a decrease in RER at 48 h-96 h (P < 0.05-P < 0.001). Accumulated changes (area under curve) revealed a greater relative decrease in accumulated RFD at 100 ms by -2727 ± 309 (%h; P < 0.05) and 200 ms by -3035 ± 271 (%h; P < 0.001) compared with MVC, which decreased, by -1956 ± 234 (%h). In conclusion, RFD and RER are both markedly reduced following a bout of maximal eccentric exercise. This association suggests that exercise-induced decrements in RFD can, in part, be explained decrements in neural drive.
本研究调查了单次离心运动后力量发展收缩速率（RFD）和神经驱动的变化。24名受试者进行了15×10次最大等速离心膝关节伸展收缩。在运动后恢复的24、48、72、96和168小时，测量等长RFD（30、50、100和200毫秒）、标准化RFD[最大自主收缩（MVC）的1/6、1/2和2/3]和肌电图上升速率（RER；30、50和75毫秒）。RFD在48小时时下降28%-42%达到峰值（P<0.01-P<0.001），并在168小时时仍处于较低水平（P<0.05）。MVC的2/3处的标准化RFD下降22%-39%（P<0.01），在72小时时达到峰值，并在168小时时恢复到基线水平。RFD的这些变化与48小时至96小时时RER的下降相关（P<0.05-P<0.001）。累积变化（曲线下面积）显示，与MVC相比，100毫秒时累积RFD的相对下降幅度更大，为-2727±309（%h；P<0.05），200毫秒时为-3035±271（%h；P<0.001），而MVC下降了-1956±234（%h）。总之，单次最大离心运动后RFD和RER均显著降低。这种关联表明，运动引起的RFD下降部分可以由神经驱动的下降来解释。
