So Billy C L, Kwok Manny M Y, Lee Nakita W L, Lam Andy W C, Lau Anson L M, Lam Allen S L, Chan Phoebe W Y, Ng Shamay S M
Gait and Motion Analysis Laboratory, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong, China.
Healthcare (Basel). 2023 Feb 3;11(3):441. doi: 10.3390/healthcare11030441.
(1) Background: Forward step-up (FSU) simulates the stance phase in stair ascension. With the benefits of physical properties of water, aquatic FSU exercise may be more suitable for patients with lower limb weakness or pain. The purpose of this study is to investigate the effect of progressive steps per min on the surface electromyography (sEMG) of gluteus maximus (GM), biceps femoris (BF), rectus femoris (RF), and gastrocnemius (GA), when performing FSU exercise with different steps per min in water and on land. (2) Methods: Participants (N = 20) were instructed to perform FSU exercises at different steps per min (35, 60, and 95 bpm) in water and on land. The sEMG of the tested muscles were collected. The percentage maximum voluntary isometric contraction (%MVIC) of GM, RF, GA and BF at different environments and steps per min was compared. (3) Result: There was a statistically significant difference of %MVIC of RF at all steps per min comparisons regardless of the movement phases and environments ( < 0.01, except for descending phases of 35 bpm vs. 60 bpm). All tested muscles showed a statistically significant lower muscle activation in water ( < 0.05) (4) Conclusion: This study found that the %MVIC of the tested muscle in both investigated environments increase as steps per minute increases. It is also found that the movement pattern of FSU exercise activates RF the most among all the tested muscles. Muscle activation of all tested muscles is also found to be smaller in water due to buoyancy property of water. Aquatic FSU exercise might be applicable to patients with lower limb weakness or knee osteoarthritis to improve their lower limb strength.
(1) 背景：向前上台阶（FSU）模拟上楼梯时的站立阶段。鉴于水的物理特性带来的益处，水上FSU运动可能更适合下肢无力或疼痛的患者。本研究的目的是调查在水中和陆地上以不同每分钟步数进行FSU运动时，每分钟递增步数对臀大肌（GM）、股二头肌（BF）、股直肌（RF）和腓肠肌（GA）表面肌电图（sEMG）的影响。(2) 方法：指导参与者（N = 20）在水中和陆地上以不同的每分钟步数（35、60和95次/分钟）进行FSU运动。收集受试肌肉的sEMG。比较不同环境和每分钟步数下GM、RF、GA和BF的最大自主等长收缩百分比（%MVIC）。(3) 结果：无论运动阶段和环境如何，在所有每分钟步数比较中，RF的%MVIC均存在统计学显著差异（P < 0.01，35次/分钟与60次/分钟下降阶段除外）。所有受试肌肉在水中的肌肉激活均显示出统计学显著降低（P < 0.05）。(4) 结论：本研究发现，在两个研究环境中，受试肌肉的%MVIC均随每分钟步数增加而增加。还发现FSU运动的运动模式在所有受试肌肉中对RF的激活最大。由于水的浮力特性，所有受试肌肉在水中的肌肉激活也较小。水上FSU运动可能适用于下肢无力或膝关节骨关节炎患者以增强其下肢力量。
