Graduate School, Department of Physical Therapy, College of Health Science, Gachon University, Incheon 21936, Korea.
Department of Rehabilitation Sciences, College of Applied Medical Sciences, King Saud University, Riyadh 11451, Saudi Arabia.
Int J Environ Res Public Health. 2022 Oct 26;19(21):13891. doi: 10.3390/ijerph192113891.
Muscles are affected at the cellular level by exercised-induced fatigue, inducing changes in their stiffness. Examining muscle stiffness can improve the knowledge of various pathologic conditions, such as pain and injury. The objective of this study was to examine the stiffness of the medial gastrocnemius (MG) muscle and the lateral gastrocnemius (LG) muscle to determine the changes in stiffness, and to assess the differences in the stiffness between the MG and the LG, as affected by muscle fatigue measured using shear wave elastography (SWE) and a MyotonPRO after inducing muscle fatigue. A total of 35 healthy young adults participated in the study. The stiffness of the MG and the LG were assessed before and after a muscle fatigue protocol (MFP), which included three sets of 50 eccentric contractions of the calf muscles of the dominant leg, at rest, and at maximum voluntary contraction (MVC). The measurements were taken with SWE and the MyotonPRO simultaneously. Compared to baseline, the resting stiffness of the MG and the LG significantly increased immediately, 24 h, and 48 h after muscle fatigue ( < 0.05); however, during MVC, the stiffness of the MG decreased ( < 0.05) and that of the LG showed no change ( > 0.05). When the stiffness of the MG and the LG were compared before and after the MFP, changes in the stiffness of the MG were significantly greater than those in the LG ( < 0.05). This signifies that the MG was more affected by the exercise-induced muscle fatigue than was the LG. The assessment of musculoskeletal tissue and its characteristics, before and after eccentric exercise, is crucial in the prevention of overuse injuries associated with repeated exposure to both low and high levels of force.
肌肉在细胞水平上受到运动引起的疲劳的影响，导致其硬度发生变化。检查肌肉硬度可以提高对各种病理状况的认识，例如疼痛和损伤。本研究的目的是检查内侧腓肠肌（MG）和外侧腓肠肌（LG）的硬度，以确定硬度的变化，并使用剪切波弹性成像（SWE）和 MyotonPRO 评估肌肉疲劳后测量的肌肉疲劳对 MG 和 LG 之间硬度差异的影响。共有 35 名健康的年轻成年人参与了这项研究。在肌肉疲劳方案（MFP）之前和之后评估 MG 和 LG 的硬度，该方案包括三组 50 次主导腿小腿肌肉的离心收缩，在休息时和最大自主收缩（MVC）时进行。同时使用 SWE 和 MyotonPRO 进行测量。与基线相比，MG 和 LG 的静息硬度在肌肉疲劳后立即、24 小时和 48 小时显着增加（<0.05）；然而，在 MVC 期间，MG 的硬度降低（<0.05），而 LG 的硬度没有变化（>0.05）。当比较 MFP 前后 MG 和 LG 的硬度时，MG 的硬度变化明显大于 LG（<0.05）。这表明 MG 比 LG 更容易受到运动引起的肌肉疲劳的影响。在预防与反复暴露于低水平和高水平力相关的过度使用损伤方面，评估肌肉骨骼组织及其特征在离心运动前后至关重要。
