Tomida Kouki, Nakae Hajime
Department of Physical Therapy, Akita Rehabilitation College, 1-4-80, Barajima.
Department of Emergency and Critical Care Medicine, Graduate School of Medicine, Akita University 1-1-1 Hondo Akita, Japan.
Medicine (Baltimore). 2020 Nov 20;99(47):e23156. doi: 10.1097/MD.0000000000023156.
Muscular contracture may be caused by immobility-induced muscle atrophy and skeletal muscle hypoxia. Belt electrode skeletal muscle electrical stimulation (B-SES) is a new type of neuromuscular electrical stimulation that can simultaneously contract the lower limb muscle groups, in contrast to the conventional pad-type electrodes. B-SES can suppress muscular atrophy and relieve hypoxia of the skeletal muscle and is considered an appropriate strategy for preventing muscular contracture. However, the effect of B-SES on muscle flexibility has not been verified. This study aimed to compare the immediate effects of B-SES on skeletal muscle flexibility using different stimulation modes before the clinical study.
We conducted a randomized controlled pilot trial with cross-over analysis of 10 healthy subjects. The participants were subjected to three stimulus conditions (Disuse B-SES, Metabolic B-SES, and Control) with a minimal interval of 1 day between interventions, and the lower limb flexibility before and after the B-SES intervention was evaluated. Lower extremity flexibility was evaluated based on the hamstring muscle stiffness and sit-and-reach distance. For each endpoint, within-group comparisons were performed before and after the intervention and were compared between the groups using paired t-tests. Changes in each endpoint before and after the intervention were analyzed using repeated-measures analysis of variance and the Bonferroni method. The significance level was 0.05.
Ten healthy individuals participated in all three interventions with a washout period between each intervention. In the Metabolic B-SES group, the sit-and-reach distance after the intervention was significantly higher than that before the intervention (P < 0.05). A comparison of the change in the sit-and-reach distance among the three groups before subsequent tests showed that the Metabolic B-SES group had a significantly increased sit-and-reach distance compared with the control group (P < 0.05).
Metabolic B-SES was effective for the immediate improvement of flexibility of the lower limb muscles. Therefore, Metabolic B-SES may be useful as a strategy for preventing muscular contracture.
肌肉挛缩可能由制动引起的肌肉萎缩和骨骼肌缺氧所致。与传统的贴片式电极不同，带状电极骨骼肌电刺激（B-SES）是一种新型的神经肌肉电刺激，可同时使下肢肌群收缩。B-SES可抑制肌肉萎缩并缓解骨骼肌缺氧，被认为是预防肌肉挛缩的一种合适策略。然而，B-SES对肌肉柔韧性的影响尚未得到验证。本研究旨在在临床研究之前，比较B-SES使用不同刺激模式对骨骼肌柔韧性的即时影响。
我们对10名健康受试者进行了一项采用交叉分析的随机对照试验。参与者接受三种刺激条件（废用性B-SES、代谢性B-SES和对照），干预之间的间隔至少为1天，并评估B-SES干预前后的下肢柔韧性。基于腘绳肌僵硬度和坐立前屈距离评估下肢柔韧性。对于每个终点，在干预前后进行组内比较，并使用配对t检验在组间进行比较。使用重复测量方差分析和Bonferroni方法分析干预前后每个终点的变化。显著性水平为0.05。
10名健康个体参与了所有三种干预，每次干预之间有洗脱期。在代谢性B-SES组中，干预后的坐立前屈距离显著高于干预前（P<0.05）。后续测试前三组之间坐立前屈距离变化的比较表明，与对照组相比，代谢性B-SES组的坐立前屈距离显著增加（P<0.05）。
代谢性B-SES对即时改善下肢肌肉柔韧性有效。因此，代谢性B-SES可能作为预防肌肉挛缩的一种策略。
