Research Institute for Sport and Exercise, University of Canberra, ACT, Canberra, Australia.
Australian Institute of Sport, Canberra, ACT, Australia.
J Strength Cond Res. 2022 Sep 1;36(9):2622-2627. doi: 10.1519/JSC.0000000000003843. Epub 2020 Oct 15.
Everett, KLA, Chapman, DW, Mitchell, JA, and Ball, N. Changes in loaded countermovement jumps during precompetition and competition training mesocycles in elite rowers. J Strength Cond Res 36(9): 2622-2627, 2022-To assess changes in velocity, displacement, and power as an indicator of neuromuscular fatigue (NMF) within and between precompetition and competition mesocycles in elite male rowers using loaded countermovement jumps (CMJs). Twenty highly trained rowers completed regular training (on-water rowing, rowing ergometer, and resistance training sessions) in 2 consecutive mesocycles. Athletes completed a single set of 6 loaded (20 kg) CMJs in the first and final week of each mesocycle. Countermovement jumps were assessed for jump height (JH), eccentric displacement, mean velocity (MV), eccentric MV (EMV), and mean power. Changes between time points were reported as Cohen's d effect sizes (95% confidence interval [CI]). The magnitude of the differences was also considered based on their relative strength levels using a linear mixed model. Within the precompetition mesocycle, trivial-to-small reductions for all variables (0.5-4.1%) were observed. During the competition mesocycle, trivial-to-small increases were shown for EMV (1.4%) and eccentric displacement (2.0%) with no change in JH and small reductions in MV (0.5%) and mean power (2.8%). No differences between the precompetition and competition mesocycles were shown. Only mean power showed a significant reduction in weaker athletes (3.2%) compared with stronger athletes (2.3%). Training completed during a precompetition and competitive mesocycle did not result in significant decreases in athlete's loaded CMJ performance, indicating that NMF was minimized. Alternatively, use of a loaded CMJ may not be sensitive enough to observe NMF in elite rowers during the mesocycle immediately leading into and during a competition mesocycle.
埃弗雷特、KLA、查普曼、DW、米切尔、JA 和鲍尔，N. 精英赛艇运动员在比赛前和比赛训练中周期性变化对负荷反跳的影响。J 力量与调节研究 36(9):2622-2627,2022-评估使用负荷反跳（CMJ）的速度、位移和功率变化，作为精英赛艇运动员比赛前和比赛周期性变化中神经肌肉疲劳（NMF）的指标。20 名高水平赛艇运动员在连续 2 个周期性变化中完成了常规训练（水上划船、划船测功计和阻力训练课程）。运动员在每个周期性变化的第一周和最后一周完成了一组 6 次的 20 公斤负荷 CMJ。CMJ 评估了跳跃高度（JH）、偏心位移、平均速度（MV）、偏心 MV（EMV）和平均功率。报告了时间点之间的变化，以 Cohen 的 d 效应大小（95%置信区间 [CI]）。还根据线性混合模型中它们的相对强度水平考虑了差异的幅度。在比赛前的周期性变化中，所有变量（0.5-4.1%）都观察到微不足道的小幅度减少。在比赛周期性变化中，EMV（1.4%）和偏心位移（2.0%）表现出微不足道的小幅度增加，JH 没有变化，MV（0.5%）和平均功率（2.8%）略有减少。比赛前和比赛周期性变化之间没有差异。只有平均功率在较弱的运动员（3.2%）中比较强的运动员（2.3%）显著减少。在比赛前和比赛周期性变化期间完成的训练并没有导致运动员负荷 CMJ 表现显著下降，表明 NMF 最小化。或者，在比赛周期性变化之前和期间，使用负荷 CMJ 可能不足以观察精英赛艇运动员的 NMF。
