Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Kowloon, Hong Kong.
Scand J Med Sci Sports. 2019 Jun;29(6):816-825. doi: 10.1111/sms.13408. Epub 2019 Mar 12.
This study aimed to investigate the influence of whole-body vibration (WBV) frequency, amplitude, and body posture on lower limb muscle activation among people with chronic stroke, and whether the EMG response to vibration stimulus differed between paretic and non-paretic side. The relationship between muscle activation and WBV transmission was also examined.
Thirty-two participants with chronic stroke performed three different exercises on the WBV platform with different vibration conditions (frequency: 20 Hz, 30 Hz, 40 Hz; amplitude: 0.8 mm, 1.5 mm), or without vibration. Muscle activity in bilateral vastus medialis (VM), medial hamstrings (MH), tibialis anterior (TA), and medial gastrocnemius (MG) was measured by surface electromyography. Acceleration at the platform and bilateral hips and knees was measured by tri-axial accelerometers.
Significantly greater muscle activity was observed in the bilateral MG (P < 0.001), TA (P < 0.001), and MH (P < 0.001), but not VM, compared with the same exercises without WBV. WBV with higher amplitude or higher frequency led to greater augmentation of muscle activation (P < 0.05). Body posture significantly affected leg muscle activation (P < 0.001). WBV-induced muscle activation was largely similar between paretic and non-paretic sides, except the TA. Greater WBV-induced leg muscle activation was associated with lower WBV transmissibility measured at the more proximal joints (P < 0.05).
Adding WBV to exercise significantly increased muscle activation in the MG, TA, and MH on both the paretic and non-paretic sides of chronic stroke survivors, and the increase was dependent on the WBV amplitude, frequency, and body posture.
本研究旨在探讨全身振动(WBV)频率、振幅和体位对慢性脑卒中患者下肢肌肉激活的影响,以及振动刺激引起的肌电反应是否在患侧和非患侧之间存在差异。还研究了肌肉激活与 WBV 传递之间的关系。
32 名慢性脑卒中患者在 WBV 平台上进行了三种不同的运动,振动条件不同(频率:20Hz、30Hz、40Hz;振幅:0.8mm、1.5mm),或没有振动。通过表面肌电图测量双侧股直肌(VM)、内侧半腱肌(MH)、胫骨前肌(TA)和内侧腓肠肌(MG)的肌肉活动。通过三轴加速度计测量平台和双侧臀部和膝盖的加速度。
与无 WBV 的相同运动相比,双侧 MG(P<0.001)、TA(P<0.001)和 MH(P<0.001)的肌肉活动明显增加,但 VM 没有增加。较高振幅或较高频率的 WBV 导致肌肉激活增加更大(P<0.05)。体位显著影响腿部肌肉激活(P<0.001)。除 TA 外,患侧和非患侧的 WBV 诱导肌肉激活差异不大。更大的 WBV 诱导的腿部肌肉激活与更靠近近端关节的更低的 WBV 可传递性相关(P<0.05)。
在慢性脑卒中幸存者的患侧和非患侧,将 WBV 添加到运动中可显著增加 MG、TA 和 MH 的肌肉激活,增加幅度取决于 WBV 振幅、频率和体位。