Zhu Hao, He Li, Guo Jiaqi, Huang Binfeng, Elliott Jeannette, Jan Yih-Kuen
Department of Health and Kinesiology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
College of Physical Education and Sports, Beijing Normal University, Beijing, China.
J Sports Med Phys Fitness. 2025 Apr;65(4):571-582. doi: 10.23736/S0022-4707.24.16529-2. Epub 2024 Dec 9.
Isometric handgrip exercise (IHE) is recommended as a non-pharmacological treatment for managing blood pressure. However, the effect of various modes of IHE on neuromuscular fatigue and post-exercise blood pressure responses have not been explored. The purpose of this study was to investigate the effects of the duration and muscle mass factors of IHE on post-exercise blood pressure responses.
Twenty healthy participants were recruited for this repeated-measures study. Three isometric protocols with similar exercise load were conducted on 3 different days including: 1) unilateral IHE at 30% of maximal voluntary contraction (MVC) for 2 minutes; 2) bilateral IHE at 30% MVC for 1 minute; and 3) unilateral IHE at 20% MVC for 3 minutes. Each exercise had four bouts of IHE with two minutes of rest between bouts. The median frequency (MDF) and root mean square (RMS) of surface electromyography was used to assess the level of neuromuscular fatigue in the flexor digitorum superficialis (FDS), extensor carpi radialis longus (ECR), flexor carpi ulnaris (FCU), and extensor carpi ulnaris (ECU).
Correlation analysis revealed that FDS MDF fatigue during the bilateral IHE was moderately correlated with the immediate post-exercise systolic blood pressure change (SBP, r=0.456, P<0.05) and diastolic blood pressure change (DBP, r=0.682, P<0.01) and ten-minute post-exercise SBP change (r=0.510, P<0.05) and DBP change (r=0.569, P<0.01) during bilateral IHE at 30% MVC for 1 min. The RMS results indicate a significant correlation between ECR and DBP immediate post-exercise (r=-0.634, P<0.01) and DBP 10-minute post exercise (r=-0.484, P<0.05).
This study suggests that neuromuscular fatigue of FDS and ECR of IHE are related to post-exercise blood pressure changes.
等长握力训练（IHE）被推荐作为一种管理血压的非药物治疗方法。然而，不同模式的IHE对神经肌肉疲劳和运动后血压反应的影响尚未得到探索。本研究的目的是调查IHE的持续时间和肌肉量因素对运动后血压反应的影响。
招募了20名健康参与者进行这项重复测量研究。在3个不同的日子里进行了3种具有相似运动负荷的等长训练方案，包括：1）以最大自主收缩（MVC）的30%进行单侧IHE，持续2分钟；2）以30%MVC进行双侧IHE，持续1分钟；3）以20%MVC进行单侧IHE，持续3分钟。每次训练有4组IHE，组间休息2分钟。使用表面肌电图的中位频率（MDF）和均方根（RMS）来评估指浅屈肌（FDS）、桡侧腕长伸肌（ECR）、尺侧腕屈肌（FCU）和尺侧腕伸肌（ECU）的神经肌肉疲劳水平。
相关性分析显示，在以30%MVC进行1分钟双侧IHE期间，双侧IHE期间FDS的MDF疲劳与运动后即刻收缩压变化（SBP，r = 0.456，P < 0.05）、舒张压变化（DBP，r = 0.682，P < 0.01）以及运动后10分钟SBP变化（r = 0.510，P < 0.05）和DBP变化（r = 0.569，P < 0.01）呈中度相关。RMS结果表明，ECR与运动后即刻DBP（r = -0.634，P < 0.01）和运动后10分钟DBP（r = -0.484，P < 0.05）之间存在显著相关性。
本研究表明，IHE中FDS和ECR的神经肌肉疲劳与运动后血压变化有关。
