Spectral Properties of H-Reflex Recordings After an Acute Bout of Whole-Body Vibration

Context:Despite the widespread use of whole-body vibration (WBV), especially in recent years, its neurophysiological mechanism is still unclear and it is yet to be determined whether acute and short-term WBV exposure produce neurogenic enhancement for agility.Objective:To compare the acute and short-term effects of WBV on the H-reflex-recruitment curve and agility.Design:Cross-over study.Setting:Clinical electrophysiology laboratory.Participants:20 nonathlete male volunteers (mean age 24.85 ± 3.03 y).Main Outcome Measures:Subjects were randomly divided into 2 groups, H-reflex and agility. In the sham protocol, subjects stood on the turned-off vibration plate while maintaining the semisquat position, and then, after a 2-wk washout, vibration-training sessions were performed in the same position with a frequency of 30 Hz and an amplitude of 3 mm. H-reflex-recruitment curve was recorded and the agility test of a shuttle run was performed before and after the first session and also 48 h after the 11th session in both sham and vibration-training protocols.Results:Acute effects of WBV training caused a significant decrease of threshold amplitude and H-max/M-max (P = .01 and P = .04, respectively). Short-term WBV training significantly decreased the threshold intensity of the soleus H-reflex-recruitment curve (P = .01) and caused a decrease and increase respectively, in the threshold intensity and the area under the recruitment curve.Conclusions:The results suggest an inhibitory effect of acute WBV training on the H-reflex response.

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Acute exposure to microgravity does not influence the H-reflex with or without whole body vibration and does not cause vibration-specific changes in muscular activity

Journal of Electromyography and Kinesiology ◽

10.1016/j.jelekin.2013.02.010 ◽

2013 ◽

Vol 23 (4) ◽

pp. 872-878 ◽

Cited By ~ 11

Author(s):

Andreas Kramer ◽

Albert Gollhofer ◽

Ramona Ritzmann

Keyword(s):

Whole Body Vibration ◽

Muscular Activity ◽

H Reflex ◽

Acute Exposure ◽

Whole Body ◽

Body Vibration

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Motoneuron Function Does not Change Following Whole-Body Vibration in Individuals With Chronic Ankle Instability

Journal of Sport Rehabilitation ◽

10.1123/jsr.2017-0364 ◽

2019 ◽

Vol 28 (6) ◽

pp. 614-622 ◽

Cited By ~ 2

Author(s):

Dana M. Otzel ◽

Chris J. Hass ◽

Erik A. Wikstrom ◽

Mark D. Bishop ◽

Paul A. Borsa ◽

...

Keyword(s):

Ankle Instability ◽

Whole Body Vibration ◽

Position Sense ◽

Chronic Ankle Instability ◽

Joint Position Sense ◽

Whole Body ◽

Control Group ◽

Joint Position ◽

Acute Bout ◽

Body Vibration

Context: Following a lateral ankle sprain, ∼40% of individuals develop chronic ankle instability (CAI), characterized by recurrent injury and sensations of giving way. Deafferentation due to mechanoreceptor damage postinjury is suggested to contribute to arthrogenic muscle inhibition (AMI). Whole-body vibration (WBV) has the potential to address the neurophysiologic deficits accompanied by CAI and, therefore, possibly prevent reinjury. Objective: To determine if an acute bout of WBV can improve AMI and proprioception in individuals with CAI. Design and Participants: The authors examined if an acute bout of WBV can improve AMI and proprioception in individuals with CAI with a repeated-measures design. A total of 10 young adults with CAI and 10 age-matched healthy controls underwent a control, sham, and WBV condition in randomized order. Setting: Biomechanics laboratory. Intervention: WBV. Main Outcome Measures: Motoneuron pool recruitment was assessed via Hoffmann reflex (H-reflex) in the soleus. Proprioception was evaluated using ankle joint position sense at 15° and 20° of inversion. Both were assessed prior to, immediately following, and 30 minutes after the intervention (pretest, posttest, and 30mPost, respectively). Results: Soleus maximum H-reflex:M-response (H:M) ratios were 25% lower in the CAI group compared with the control group (P = .03). Joint position sense mean constant error did not differ between groups (P = .45). Error at 15° in the CAI (pretest 0.8 [1.6], posttest 2.0 [2.8], 30mPost 2.0 [1.9]) and control group (pretest 0.8 [2.0], posttest 0.6 [2.9], 30mPost 0.5 [2.1]) did not improve post-WBV. Error at 20° did not change post-WBV in the CAI (pretest 1.3 [1.7], posttest 1.0 [2.4], 30mPost 1.5 [2.2]) or control group (pretest −0.3 [3.0], posttest 0.8 [2.1], 30mPost 0.6 [1.8]). Conclusion: AMI is present in the involved limb of individuals with CAI. The acute response following a single bout of WBV did not ameliorate the presence of AMI nor improve proprioception in those with CAI.

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