NeuroMuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.
Department of Human Movement and Sports Performance, University of Seville, Seville, Spain.
Exp Physiol. 2022 Sep;107(9):1046-1060. doi: 10.1113/EP090371. Epub 2022 Aug 17.
What is the central question of this study? Do males and females differ in fatiguability during dynamic loadings, and what are the acute neuromuscular and hormonal responses to 20 versus 40% velocity-loss resistance loadings? How does an 8-week velocity-loss resistance training period modify acute neuromuscular and hormonal responses in males and females? What is the main finding and its importance? Using resistance training methods that regulated the within-set fatigue limit, males appeared to be more susceptible to fatigue than females before the training period. This between-sex difference was diminished after training. The predominant mechanisms of fatigue from 20 and 40% velocity-based resistance training appear to be within the musculature.
Scientific examination of velocity-based resistance training (VBRT) has increased recently, but how males and females respond to different VBRT protocols or how these acute responses are modified after a period of training is unknown. Habitually resistance-trained males and females followed either a 20 or 40% velocity-loss programme for 8 weeks. Acute squat loading tests (five sets, 70% one-repetition maximum load, 3 min rest) were performed before and after the training period. Tests of maximum neuromuscular performance and blood sampling were conducted before, within 10 min of completion (POST) and 24 h after each acute loading test. Testing included countermovement jump, resting femoral nerve electrical stimulation and bilateral isometric leg press. Blood samples were analysed for whole-blood lactate, serum testosterone, cortisol, growth hormone and creatine kinase concentrations. Countermovement jump height, maximum isometric bilateral leg-press force and the force from a 10 Hz doublet decreased in all groups at POST after 20 and 40% velocity loss. Only males showed reduced force from the 100 Hz doublet and voluntary force over 100 ms at POST before training. The 40% velocity loss led to increased blood lactate and growth hormone responses before training in both males and females. After training, more systematic and equivalent responses in force over 100 ms, force from a 100 Hz doublet and blood lactate were observed regardless of sex/VBRT protocol. Overall, acute responses were greater from 40% VBRT, and males were more susceptible to acute loss in force production capacity before the training period. These VBRT protocol- and sex-related differences were diminished after training.
本研究的核心问题是什么？在动态负荷下，男性和女性的疲劳程度是否存在差异，以及对 20%和 40%速度损失阻力负荷的急性神经肌肉和激素反应是什么？8 周的速度损失阻力训练如何改变男性和女性的急性神经肌肉和激素反应？主要发现及其重要性是什么？使用调节组内疲劳极限的阻力训练方法，男性在训练前似乎比女性更容易疲劳。这种性别差异在训练后减弱。来自 20%和 40%基于速度的阻力训练的疲劳的主要机制似乎在肌肉内。
最近对基于速度的阻力训练（VBRT）的科学研究有所增加，但男性和女性对不同的 VBRT 方案的反应如何，或者经过一段时间的训练后这些急性反应如何改变，尚不清楚。习惯性抗阻训练的男性和女性分别进行了 8 周的 20%或 40%速度损失方案。在训练前后进行了急性深蹲负荷测试（五组，70%一次重复最大负荷，3 分钟休息）。在每次急性负荷测试前、完成后 10 分钟内（POST）和 24 小时后进行最大神经肌肉性能测试和血液取样。测试包括下蹲跳、休息时股神经电刺激和双侧等长腿推。血液样本分析全血乳酸、血清睾酮、皮质醇、生长激素和肌酸激酶浓度。在 POST 时，所有组在 20%和 40%速度损失后，下蹲跳高度、最大双侧等长腿推力量和 10Hz 双脉冲的力量下降。只有男性在训练前 POST 时显示 100Hz 双脉冲的力量和超过 100ms 的自愿力量下降。在训练前，40%速度损失导致男性和女性的血液乳酸和生长激素反应增加。训练后，无论性别/ VBRT 方案如何，100ms 以上的力量、100Hz 双脉冲的力量和血液乳酸的反应更加系统和等效。总的来说，来自 40% VBRT 的急性反应更大，在训练前男性更容易出现急性力量产生能力下降。这些 VBRT 方案和性别相关的差异在训练后减弱。
