Department of Kinesiology and Health Promotion, The University of Kentucky, Lexington, KY, USA.
J Musculoskelet Neuronal Interact. 2024 Jun 1;24(2):107-119.
The current study investigated performance fatigability (PF) and time course of changes in force, electromyographic amplitude (EMG AMP) and frequency (EMG MPF), and neuromuscular efficiency (NME) during a sustained, isometric, handgrip hold to failure (HTF) using the rating of perceived exertion (RPE)-Clamp Model.
Twelve males performed a handgrip HTF anchored to RPE=5. The time to task failure (T), force (N), EMG AMP and MPF, and NME (normalized force/ normalized EMG AMP) were recorded. Analyses included a paired samples t-test for PF at an alpha of p<0.05, 1-way repeated measures ANOVA across time and post-hoc t-tests (p<0.0025) for force, EMG AMP and MPF, and NME responses.
The PF (pre- to post- maximal force % decline) was 38.2±11.5%. There were decreases in responses, relative to 0% T, from 40% to 100% T (force), at 30%, 60%, and 100% T (EMG AMP), from 10% to 100% T(EMP MPF), and from 50% to 65%, and 80% to 100% T (NME) (p<0.0025).
The RPE-Clamp Model in this study demonstrated that pacing strategies may be influenced by the integration of anticipatory, feedforward, and feedback mechanisms, and provided insights into the relationship between neuromuscular and perceptual responses, and actual force generating capacity.
本研究采用感觉疲劳评分（RPE）钳夹模型，调查了在等长、手握持力衰竭（HTF）至力衰竭过程中，力、肌电图幅度（EMG AMP）和频率（EMG MPF）、神经肌肉效率（NME）的疲劳表现（PF）和变化时程。
12 名男性进行了手 HTF 至 RPE=5 的 HTF。记录了任务失败时间（T）、力（N）、EMG AMP 和 MPF 以及 NME（归一化力/归一化 EMG AMP）。分析包括对 PF 进行配对样本 t 检验（α值为 p<0.05），对力、EMG AMP 和 MPF 以及 NME 进行 1 路重复测量方差分析和事后 t 检验（p<0.0025）。
PF（最大力前至后百分比下降）为 38.2±11.5%。与 0% T 相比，从 40%至 100% T （力）、30%、60%和 100% T（EMG AMP）、10%至 100% T（EMG MPF）以及 50%至 65%和 80%至 100% T（NME）的反应都有所下降（p<0.0025）。
本研究中的 RPE 钳夹模型表明，节奏策略可能受到预期、前馈和反馈机制的综合影响，并深入了解了神经肌肉和感知反应与实际产生力能力之间的关系。
