Table of Contents Author Guidelines Submit a Manuscript
Rehabilitation Research and Practice
Volume 2018, Article ID 9319258, 11 pages
https://doi.org/10.1155/2018/9319258
Clinical Study

Effects of Stochastic Resonance Whole-Body Vibration in Individuals with Unilateral Brain Lesion: A Single-Blind Randomized Controlled Trial: Whole-Body Vibration and Neuromuscular Function

1Department of Physiotherapy, Bern University Hospital, Inselspital Bern, Switzerland
2SRO AG, Hospital of Langenthal, Langenthal, Switzerland
3Department of Health Professions, Bern University of Applied Sciences, Bern, Switzerland
4Academy of Physiotherapy and Training Education, Grenzach-Wyhlen, Germany

Correspondence should be addressed to Slavko Rogan; hc.hfb@nagor.okvals

Received 27 January 2018; Accepted 18 July 2018; Published 1 August 2018

Academic Editor: Trentham Furness

Copyright © 2018 Kaspar Herren et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Introduction. Stochastic resonance whole-body vibration (SR-WBV) devices are promising sensorimotor interventions to address muscle weakness and to improve balance and mobility particularly in the elderly. However, it remains inconclusive whether individuals with stroke or traumatic brain injury (TBI) can profit from this method. The aim of this prospective single-blind randomized controlled trial was to investigate the effects of SR-WBV on muscle strength as well as gait and balance performance in this population. Methods. Forty-eight individuals with stroke or TBI were randomly allocated to an experimental and a sham group. Participants were exposed daily to 5 consecutives 1-minute SR-WBV sessions, whereas the experimental group trained in a standing position with 5 Hz and the sham group in a seated position with 1 Hz. Isometric muscle strength properties of the paretic knee extensor muscles as well as balance and gait performance were measured at baseline, after the first session and after two weeks of SR-WBV. Results. Both groups showed short- and long-term effects in gait performance. However, no between-group effects could be found at the three measurement points. Discussion. Complementary SR-WBV showed no beneficial effects immediately after the intervention and after two weeks of conventional rehabilitation therapy. Future research is needed to identify the potential efficacy of SR-WBV in individuals with stroke and TBI using shorter and less exhausting test procedures and a generally prolonged intervention time.

1. Introduction

Stroke was reported to be the largest cause of complex disability in adults and traumatic brain injury (TBI) is the most common cause of long-term disability and death among young adults [15]. Both conditions represent an enormous socioeconomic and healthcare burden [57]. Individuals with stroke or TBI suffer from reduced muscle strength, spasticity, sensorimotor deficits, contractures, impaired balance resulting in gait disorders, and therefore reduced independence in everyday life [813]. It was shown that individuals with stroke walking at 0.25 m/s (SD 0.1) only achieve household ambulation, whereas only 18% are able to walk at 0.80 m/s (SD 0.15) after rehabilitation, a gait speed needed for community ambulation [10, 1416]. In addition, they were at a four times higher risk of falling and a ten times higher risk of hip fractures compared to healthy individuals [14]. For these reasons, many of the stroke or TBI survivors are not anymore able to participate in their premorbid social and daily life [8, 17].

A major aim of neurological rehabilitation is to improve muscle function, balance, and gait performance, with improving walking ability being one of the most often stated goals by individuals with stroke [18, 19]. Lower extremity strength and balance performance appear to be interrelated as well as directly correlated with gait performance in individuals with stroke and TBI, whereby decreases in these parameters are reported to be important risk factors for falls in these populations [9, 2027]. The evident sensorimotor impairments can be treated with a conventional multidisciplinary rehabilitation approach, which was recently successfully supplemented by robotic devices, virtual reality, treadmill training, electrical stimulation, or whole-body vibration (WBV) training [15, 2831].

Vibration plates that are frequently used in elderly population [30, 33, 34] generate either sinusoidal vertical vibration with a frequency between 30 and 60 Hz and amplitude of 0-12 mm or side alternating sinusoidal vibrations with a frequency of 12-30 Hz and an amplitude of 0-12 mm [30, 33]. Huang et al. [35] postulated WBV amplitude, frequency, body postures, and their interactions significantly influenced the vibration transmissibility and signal purity among person with chronic stroke. The transmissibility decreased with increased frequency, increased amplitude, or increased knee flexion angle. The average vibration intensity measured was up to 4.94 g and the transmissibility ratio was 0.04-0.30 and the vibration intensity was 0.11-0.60 g.

The evidence on the treatment effects of sinusoidal WBV (SS-WBV) in individuals with stroke, however, is somewhat contradictory. Whereas some studies showed beneficial short- and long-term effects on gait and balance performance as well as mobility, trunk stability, muscle strength, and muscle tone [3642], others reported no benefits or even adverse effects of SS-WBV compared to conventional exercise therapy [4350]. In addition, no studies were found investigating the effects of SS-WBV on the impairments of individuals with TBI.

The physiological mechanisms responsible for the effects of SS-WBV are based on different theories. On the one side, it was postulated that SS-WBV causes changes in the length of the muscle-tendon complex, which, as a consequence, stimulates muscle spindles leading to increased reflexive activation of the alpha-motor units [32, 51]. On the other side, an increase of intramuscular temperature or a postactivation potentiation of the muscle twitch response was hypothesized to lead to an acute enhancement of muscle power [52, 53]. Moreover, changes in thixotropic properties of the vibrated muscles, enhanced hormonal secretion of testosterone, cortisol, and growth hormones, and even placebo effects might be responsible for effects such as strength increase [46, 5456].

In contrast to SS-WBV platforms, the Zeptor med® vibrates randomly (stochastic) in three different planes with frequencies of 1-12 Hz and an amplitude of 3 mm [34, 57, 58]. In contrast to sinusoidal signals, stochastic stimuli are known to efficiently affect the membrane potential of nerve cells, resulting in an activation of the neuromuscular systems already at low intensities [34]. However, no studies are available evaluating stochastic resonance WBV (SR-WBV) as a treatment option for individuals with stroke or TBI. In general, any of the aforementioned forms of WBV can be recommended as a safe additional training intervention with very rare and normally harmless side effects such as tingling sensations in the legs, muscle soreness, fatigue, or mild dizziness [50, 59]. The physical strain of WBV is low and the training is not time consuming and therefore potentially useful for many different complaints of young and even frail elderly people [28, 6062]. For these reasons, the aims of the current study were to investigate whether a complementary SR-WBV intervention has beneficial short- and long-term effects on isometric muscle strength properties, balance, and gait performance in individuals with an acute unilateral brain lesion due to stroke or TBI.

2. Methods

2.1. Study Design

This study was conducted as a single-center, single-blind randomized controlled trial. The study protocol was approved by the ethics committee of the Cantone of Bern, Switzerland (Reference no. 225/08).

2.2. Participants

Study participants were consecutively recruited among individuals with a first-ever stroke or TBI that were hospitalized at the Neurology Department of the Bern University Hospital between June 2010 and October 2014. Inclusion criteria were clinical diagnosis of an acute (less than 3 months but more than 8 days after onset) first-ever unilateral brain lesion by means of stroke or TBI, aged between 18 and 80 years, presence of balance and gait disorders but the ability to stand still and to walk 10 meters without assistance, and sufficient cognitive and linguistic skills to understand the test and therapy instructions. Individuals were excluded in case of documented comorbidities such as Parkinson’s disease, polyneuropathy, severe uncorrected visual impairments or alcohol abuse, and complaints defined as contraindications for the intervention [6365]. All participants provided written informed consent before inclusion.

The allocation to an experimental or a sham group as well as the determination of the order of the biomechanical measurements was concealed and conducted separately for the individuals with stroke or TBI using computer-generated 4-block randomization schemes. For each wave of participants, the prepared sealed opaque envelopes were randomly allocated by an administrative assistant not associated with the study. Participants, investigators, and statistician were blinded concerning assignment to interventions, whereas therapists could not be blinded.

2.3. Measurement Procedures

After inclusion, the participants’ performance in activities of daily life, injury severity, and self-perceived fear of falling was assessed using the Extended Barthel Index (EBI), the National Institute of Health Stroke Scale (NIHSS), and the Falls Efficacy Scale International (FES-I) [6669]. Subsequently, the participants’ affected leg was equipped with bipolar surface electrodes (Ambu Blue Sensor N, Ambu A/S, Ballerup, Denmark) for the derivation of the electromyographic (EMG) activity of the muscles vastus medialis (VM), vastus lateralis (VL), tibialis anterior (TA), soleus (SOL), and medial gastrocnemius (GM). Electrode placement was conducted in accordance with the SENIAM recommendations [70] and electrodes were replaced when the skin impedance was greater than 5 kΩ. In addition, a triaxial accelerometer (Model 317A, Noraxon, Scottsdale, AZ, USA) was attached to the lateral malleolus of the affected leg for gait event detection. The electrodes were connected via preamplifiers (base gain: 500; integrated band-pass filter: 10–500 Hz) and the accelerometer directly to a telemetric system (TeleMyo 2400 G2, Noraxon USA Inc., Scottsdale, AZ, USA), whereby the transmitter unit was carried by the participants on their back. Furthermore, the EMG activity of the investigated muscles during a maximal voluntary isometric contraction (MVIC) was assessed for normalization purposes.

The following biomechanical measurements were carried out in a randomized order:(1)Isometric strength properties of the quadriceps muscle: individuals were placed in a sitting position on a previously introduced custom-built knee extension table [71]. The hip and knee joints were thereby fixed in 90° flexion and the lower end of the tibia of the affected leg was attached by a sling to a unidimensional strain gauge (KM 1500S, Megatron, Munich, Germany). Each individual was then instructed to explosively generate a maximal isometric force towards extension and to maintain this maximal force for five seconds. After a practice trial, the individuals performed two measurement trials with 15 seconds of rest in between.(2)Balance properties: individuals were instructed to assume a semi-tandem stance position (affected leg placed behind) on a force plate (type 9286BA, Kistler, Winterthur, Switzerland) and to maintain this position for 15 seconds with the gaze fixed at a point on the wall in front of them. The position of the feet was standardized with a rigid plastic frame. To ensure the individuals’ safety, a physiotherapist was standing next to them during the task. After a rest of at least 30 seconds, the task was repeated one more time.(3)Gait characteristics: individuals were asked to walk a distance of 10 meters on a level surface as fast and as safely possible. Gait characteristics were thereby measured using the Locomètre® system (Satel, Toulouse, France), which was connected to the individuals’ feet by two thin filaments [72]. To ensure the individuals’ safety, a physiotherapist was walking next to them during the task. After a rest of at least 1 minute, the task was repeated one more time.

Strain gauge, force plate, EMG, and accelerometer signals were amplified using a custom-built universal amplifier (UMV, uk-labs, Kempen, Germany) and sampled at a rate of 1 kHz using the software package ads (version 1.12, uk-labs, Kempen, Germany), whereas the Locomètre signals were recorded without additional amplification using a software package provided by the manufacturer.

The biomechanical measurements as well as the FES-I were carried out at baseline (pre) and immediately after one series of SR-WBV training at the same day (post 1) and after the intervention period lasting two weeks (post 2), whereas the NIHSS and EBI were conducted at baseline (pre) and at the end of the intervention phase (post 2) only.

2.4. Intervention

Independently of the group allocation, all participants received individual conventional rehabilitation therapy (motor learning therapy, occupational, speech, and neuropsychological therapy) at every working day over a period of two weeks, resulting in ten days of therapy.). On each day of therapy as well as immediately after the baseline measurements, the individuals were additionally exposed to five one-minute sessions of SR-WBV (experimental group: frequency 5 Hz, amplitude 3 mm, noise level 4; sham group: 1 Hz, 3 mm, noise level 0) using a SR-WBV device (Zeptor med®, Frei Swiss AG, Zurich, Switzerland). The individuals in the experimental group were thereby assuming a free-standing position with the knees slightly flexed, while the individuals in the sham group were sitting on a wooden box with the legs placed on the vibration device. In addition, all individuals were asked to balance a half-filled 500 ml water bottle on a tray with their nonaffected arm during vibration exposure. After each vibration session, they were allowed to rest for one minute in a seated position.

2.5. Data Analysis and Outcome Measures

Several signals that were recorded during the strength and balance measurements were analyzed using the “ADS” software, whereas the gait measurements were processed using the Locomètre software and a custom-made LabVIEW program (version 11.0.1, National Instruments Corp., Austin, TX, USA).

The primary outcome parameters were defined as maximal voluntary isometric contraction (MVIC [N]) and rate of force development (RFD [N/s]), postural sway distance [32] and sway velocity [mm/s] in the mediolateral and anterior-posterior axes (calculated on the basis of the proportion of the four force sensors signals of the force plate), and gait velocity [m/s], step length [m], and stance phase duration [% of gait cycle] of the affected and unaffected legs. Secondary outcome parameters included average EMG activity [%MVIC] of several muscles during the balance task, average EMG activity [%MVIC] of several muscles during a gait cycle of the affected leg, and total scores of the NIHSS, EBI, and FES-I. For the biomechanical measurements, parameters from both trials were averaged.

2.6. Statistics

Based on an a priori power analysis using the software GPower (Faul et al. 2007), a theoretical sample size of N=70, was determined (repeated measures: within-between interactions ANOVA approach; effect size f=0.20, α error probability=0.05, power 1-β=0.90, groups=2, repetitions=2, correlation among repeated measures=0.5, nonsphericity correction ε=1, and expected dropouts=2).

Statistical analyses were based on the intention-to-treat approach (LOCF: last observation carried forward) and carried out using the software package SPSS 24 (SPSS Inc., Chicago, IL, USA). Shapiro Wilk normality tests revealed nonnormal distribution for the majority of the parameters and therefore, nonparametric procedures were applied. To investigate the short-term and long-term effects within the experimental group and sham group separately, parameters were compared between the baseline measurements (pre) and the retest measurements immediately after the first intervention (post 1) and the retest measurements after two weeks of intervention (post 2), respectively, using the Wilcoxon signed-rank test. Comparisons between the experimental group and sham group at the time points pre, post 1, and post 2 were conducted using the Mann–Whitney U test. A Bonferroni-corrected alpha-level of 0.025 was used to determine statistical significance for all tests.

3. Results

3.1. Participants

The recruitment period started in June 2010 and was stopped in October 2014 due to a lack of eligible participants. Four of the 52 initially assessed participants had to be excluded due to cognitive deficits, thrombophilia, retinal hemorrhage, and discharge during intervention time (Figure 1). Forty-eight participants were finally randomly and uniformly assigned to the experimental and sham group and completed the intended treatment. Based on the intention-to-treat approach, the 3 participants that discontinued the intervention in the experimental group were also included into final analysis.

Figure 1: CONSORT diagram of flow of participants through the study.

Group comparisons showed no significant differences for demographics at baseline as well as amount of completed complementary SR-WBV sessions at discharge (post 2) (Table 1).

Table 1: Demographics of the individuals with stroke and traumatic brain injury (TBI), therapy characteristics [n, arithmetic mean (lower/upper limit 95% confidence interval), and significance test] at baseline (pre) and amount of completed complementary SR-WBV sessions at discharge (post 2).
3.2. Primary and Secondary Outcome Parameters

Descriptive statistics were calculated and presented as medians with the respective 25th and 75th percentiles (Table 2). No statistically significant between-group differences were found at pre, post 1, and post 2 (Table 3).

Table 2: Descriptive statistics for the primary and secondary outcome parameters, presented as median with the and percentiles in brackets.
Table 3: Results for the within- and between-group comparisons (Wilcoxon signed-rank and Mann–Whitney U test, respectively) of the primary and secondary outcome parameters. Statistical significance was accepted at the p≤0.025 level (Bonferroni corrected).

Within-group comparisons, on the other hand, revealed short-term main effects (pre to post 1) for gait velocity as well as step length and stance phase duration on the affected and unaffected sides in both groups. In the experimental group, muscle activity was found to be increased for VM during gait and balance and decreased for GM during gait. The FES-I indicated no short-term effects after one SR-WBV training session.

Long-term effects (pre to post 2) could be found by a distinct increase in isometric muscle strength (experimental group) and a reduction of sway distance (ml, ap) and sway velocity (ap) in the sham group. Both groups improved regarding gait velocity, step length, and stance phase duration of the affected and unaffected leg. Tibialis anterior activity in the sham group during gait was higher after the complete intervention period compared to baseline. Long-term effects could also be found in the total scores of the FES-I and EBI in both groups and the NIHSS in the sham group.

4. Discussion

This study examined the short- and long-term effects of complementary SR-WBV on balance, strength, gait, fear of falling, and performance in activities of daily life in individuals in the acute phase of stroke and TBI randomly allocated to an experimental or sham group. The results indicated no beneficial between-group effects for complementary SR-WBV on isometric quadriceps strength, static balance, and gait performance immediately after one session and after two weeks of daily training. Both groups showed comparable short- and long-term effects for gait performance, FES-I, NIHSS, and EBI. In addition, long-term effects were found for balance performance but only in the sham group.

On the one side, these findings are in line with the results of several systematic reviews and meta-analyses showing no benefits or even adverse effects of SS-WBV on muscle strength, balance, fall rate, gait performance, mobility, activity, and participation after stroke [45, 73, 74]. On the other side, the current findings deviate from those of many individual experimental studies reporting WBV-dependent functional improvements in a stroke population.

4.1. Short-Term Effects

Tihany et al. [38], for instance, showed significant transient improvements of isometric and eccentric maximum knee extensor strength (36.6% and 22.2%, respectively) in individuals with acute stroke after one session of WBV with a frequency of 20 Hz and an amplitude of 5 mm, which has been shown to be an effective treatment modality in healthy young adults to increase muscle strength [75, 76]. Van Nes et al. [42] provided preliminary evidence for positive short-term effects of SS-WBV on some aspects of static balance in 23 individuals with chronic stroke using an economic test setting with long rest intervals of 30 minutes in order to minimize exhaustion. Furthermore, results of an investigation on the effect of a 10-minute SS-WBV session (frequency: 12 Hz, amplitude: 4 mm) on gait performance indicated improvements in gait speed and mobility quantified by the Timed Up and Go Test [36].

These discrepancies are most likely due to several factors. The vibration intensity used in the current study (frequency: 5 Hz, amplitude: 3 mm) might have been too low in order to induce the expected effects.

In addition, the participants wore shoes to stabilize their ankle joints during SR-WBV and therefore, it cannot be excluded that the possibly insufficient impulse was additionally damped by the participants’ shoes [77]. According to Freeman and Wyke [78], sensorimotor exercises are best performed without shoes to provide a maximum amount of appropriate afferent information for the sensorimotor system. Rogan et al. [79] showed that vibration training without shoes in comparison to vibration training with shoes [80] improved significantly the isometric rate of force development and increased the physical performance level in frail elderly individuals after four weeks of SR-WBV.

Furthermore, the duration of the functional measurements was about 90 minutes and included almost no resting periods. Considering the fact that individuals with stroke and TBI complain about increased mental fatigue and physical fatigability [8185], where such an intensive testing procedure might have resulted in pronounced fatigue.

4.2. Long-Term Effects

Tihany et al. [41] described a significant increase in isometric and eccentric strength of the knee extensors after 4 weeks of SS-WBV with a frequency of 20 Hz and an amplitude of 1 mm, whereby the affected leg could benefit more (32.8% and 24%, respectively) than the unaffected one (10.4% and 11.6%, respectively). For eccentric strength, an increase exceeding 22% was previously considered a clinically relevant improvement for individuals with stroke [86]. Tankisheva et al. [28] reported an isometric knee extensor strength gain of 18.7% after 6 weeks SS-WBV with increasing intensity (frequency: 35-40 Hz, amplitude: 1.7-2.5 mm). Both of these studies included challenging dynamic strength exercises such as squatting during SS-WBV sessions. Furthermore, several studies showed beneficial long-term effects of 4-6 weeks SS-WBV with vibration frequencies of 15-40 Hz on balance performance in individuals with stroke [28, 39, 40, 87, 88]. Regarding gait performance, Guo et al. [89] reported improvements in gait speed after an 8-week SS-WBV training in individuals with stroke.

As for the short-term effects, it can be assumed that the vibration intensity in the current study was too low to induce detectable changes. This assumption was to some extend supported by Petit et al. [90], who compared the effects of a high frequency/high amplitude (50 Hz/4 mm) with a low-frequency/low amplitude (30 Hz/2 mm) 6-week SS-WBV intervention in young male students. They found that high frequency/high amplitude vibration training was more effective in enhancing knee extensor strength and jump performance. Interestingly, Lee [40] could improve postural control in chronic stroke survivors using a vibration plate generating horizontal vibrations at a rate of 1-3 Hz and an amplitude of 3 mm. However, placebo effects can thereby not be excluded due to a missing sham intervention.

In the current study, participants had to stand quietly with slightly flexed knees on the vibration platform, which together with the low vibration intensity might have resulted in an even weaker physiological stimulus. In addition, all participants were standing on two separately vibrating platforms. Individuals with stroke or TBI though are not always able to distribute their body weight equally over their feet and therefore, it cannot be excluded that the participants shifted their body weight mainly over the healthy leg, resulting in an insufficient stimulation of the affected leg [91, 92].

Considering that several of the above-mentioned studies included intervention periods of 4 or more weeks, the two weeks with altogether 11 SR-WBV sessions in the current study might not have been sufficient. In contrast to this assumption, however, there is evidence showing that even with higher vibrations intensities and longer treatment durations, no beneficial effects of WBV were found in postacute and chronic stroke survivors [43, 4750]. Moreover, some of the above described beneficial effects have to be interpreted carefully, mainly due to small sample sizes (n≤20) and to the fact that WBV was administered as a supplementary treatment in the experimental group, but not in the control group [28, 38, 41].

4.3. Limitations

The fact that the participants were in the acute phase of stroke and TBI, during which spontaneous recovery can be observed [9396], was considered a limitation. The current study findings are therefore not applicable individuals with chronic stroke, whereas spontaneous recoveries could have distorted the treatment effects.

Due to difficulties in finding enough eligible patients, recruitment was stopped after 4 years of intensive efforts and 48 instead of the targeted 70 participants. Consequently, statistical analyses were underpowered, which represented another limitation of this study.

5. Conclusions

This study evaluated the short- and long-term effects of complementary SR-WBV on muscle strength, balance, and gait performance in individuals with stroke and TBI. Complementary daily SR-WBV sessions showed no additional effects compared to a sham intervention. Future research is required to identify the potential efficacy of SR-WBV protocols in individuals with stroke or TBI, particularly with regard to intensity of the vibration parameters and the duration of the intervention considering the impaired physical and mental capability of the individuals.

Data Availability

The datasets generated during the current study are available from the corresponding author on reasonable request.

Disclosure

This paper was presented as a poster at the Physioswiss Congress 2016 in Basel, Switzerland, and at the WCPT Congress 2017 in Cape Town, South Africa.

Conflicts of Interest

The authors declare that there are no conflicts of interest regarding the publication of this paper.

Acknowledgments

This study was funded by the Swiss National Science Foundation (no. 13DPD6_127280) and supported by the team of physical therapists of the Department of Physiotherapy at the Bern University Hospital.

References

  1. J. Adamson, A. Beswick, and S. Ebrahim, “Is stroke the most common cause of disability?” Journal of Stroke and Cerebrovascular Diseases, vol. 13, no. 4, pp. 171–177, 2004. View at Publisher · View at Google Scholar · View at Scopus
  2. C. Brogårdh and J. Lexell, “Effects of cardiorespiratory fitness and muscle-resistance training after stroke,” PM&R : The Journal of Injury, Function, and Rehabilitation, vol. 4, no. 11, pp. 901–907, 2012. View at Publisher · View at Google Scholar · View at Scopus
  3. J. Bruns Jr. and W. A. Hauser, “The epidemiology of traumatic brain injury: a review,” Epilepsia, vol. 44, supplement 10, pp. 2–10, 2003. View at Google Scholar · View at Scopus
  4. J. F. Burke, L. D. Lisabeth, D. L. Brown, M. J. Reeves, and L. B. Morgenstern, “Determining stroke's rank as a cause of death using multicause mortality data,” Stroke, vol. 43, no. 8, pp. 2207–2211, 2012. View at Publisher · View at Google Scholar
  5. K. Hackenberg and A. Unterberg, “Schädel-Hirn-Trauma,” Der Nervenarzt, vol. 87, no. 2, pp. 203–216, 2016. View at Publisher · View at Google Scholar
  6. A. Di Carlo, “Human and economic burden of stroke,” Age and Ageing, vol. 38, no. 1, pp. 4-5, 2009. View at Publisher · View at Google Scholar · View at Scopus
  7. S. M. A. A. Evers, J. N. Struijs, A. J. H. A. Ament, M. L. L. Van Genugten, J. C. Jager, and G. A. M. Van Den Bos, “International comparison of stroke cost studies,” Stroke, vol. 35, no. 5, pp. 1209–1215, 2004. View at Publisher · View at Google Scholar · View at Scopus
  8. M. Åström, K. Asplund, and T. Åström, “Psychosocial function and life satisfaction after stroke,” Stroke, vol. 23, no. 4, pp. 527–531, 1992. View at Publisher · View at Google Scholar · View at Scopus
  9. J. J. Eng and P.-F. Tang, “Gait training strategies to optimize walking ability in people with stroke: a synthesis of the evidence,” Expert Review of Neurotherapeutics, vol. 7, no. 10, pp. 1417–1436, 2007. View at Publisher · View at Google Scholar · View at Scopus
  10. S. E. Lord, K. McPherson, H. K. McNaughton, L. Rochester, and M. Weatherall, “Community ambulation after stroke: how important and obtainable is it and what measures appear predictive?” Archives of Physical Medicine and Rehabilitation, vol. 85, no. 2, pp. 234–239, 2004. View at Publisher · View at Google Scholar · View at Scopus
  11. B. J. McFadyen, B. Swaine, D. Dumas, and A. Durand, “Residual Effects of a Traumatic Brain Injury on Locomotor Capacity: A First Study of Spatiotemporal Patterns during Unobstructed and Obstructed Walking,” The Journal of Head Trauma Rehabilitation, vol. 18, no. 6, pp. 512–525, 2003. View at Publisher · View at Google Scholar · View at Scopus
  12. K. M. Michael, J. K. Allen, and R. F. MacKo, “Reduced ambulatory activity after stroke: the role of balance, gait, and cardiovascular fitness,” Archives of Physical Medicine and Rehabilitation, vol. 86, no. 8, pp. 1552–1556, 2005. View at Publisher · View at Google Scholar · View at Scopus
  13. G. P. Williams, A. G. Schache, and M. E. Morris, “Mobility after traumatic brain injury: Relationships with ankle joint power generation and motor skill level,” The Journal of Head Trauma Rehabilitation, vol. 28, no. 5, pp. 371–378, 2013. View at Publisher · View at Google Scholar · View at Scopus
  14. B. H. Dobkin, “Strategies for stroke rehabilitation,” The Lancet Neurology, vol. 3, no. 9, pp. 528–536, 2004. View at Publisher · View at Google Scholar · View at Scopus
  15. B. H. K. Dobkin, S. E. Nadeau, A. L. Behrman et al., “Prediction of responders for outcome measures of Locomotor experience applied post stroke trial,” Journal of Rehabilitation Research and Development , vol. 51, no. 1, pp. 39–50, 2014. View at Publisher · View at Google Scholar · View at Scopus
  16. J. Perry, M. Garrett, J. K. Gronley, and S. J. Mulroy, “Classification of walking handicap in the stroke population,” Stroke, vol. 26, no. 6, pp. 982–989, 1995. View at Publisher · View at Google Scholar · View at Scopus
  17. G. Williams, L. Ada, L. Hassett et al., “Ballistic strength training compared with usual care for improving mobility following traumatic brain injury: Protocol for a randomised, controlled trial,” Journal of Physiotherapy, vol. 62, no. 3, p. 164, 2016. View at Publisher · View at Google Scholar · View at Scopus
  18. R. W. Bohannon, A. W. Andrews, and M. B. Smith, “Rehabilitation goals of patients with hemiplegia,” International Journal of Rehabilitation Research, vol. 11, no. 2, pp. 181–183, 1988. View at Publisher · View at Google Scholar · View at Scopus
  19. J. E. Harris and J. J. Eng, “Goal Priorities Identified through Client-Centred Measurement in Individuals with Chronic Stroke,” Physiotherapy Canada, vol. 56, no. 3, pp. 171–176, 2004. View at Publisher · View at Google Scholar
  20. F. A. Batchelor, S. F. Mackintosh, C. M. Said, and K. D. Hill, “Falls after stroke,” International Journal of Stroke, vol. 7, no. 6, pp. 482–490, 2012. View at Publisher · View at Google Scholar · View at Scopus
  21. K. F. Carlson, L. A. Meis, A. C. Jensen et al., “Caregiver reports of subsequent injuries among veterans with traumatic brain injury after discharge from inpatient polytrauma rehabilitation programs,” The Journal of Head Trauma Rehabilitation, vol. 27, no. 1, pp. 14–25, 2012. View at Publisher · View at Google Scholar · View at Scopus
  22. T. T. Duong, J. Englander, J. Wright, D. X. Cifu, B. D. Greenwald, and A. W. Brown, “Relationship between strength, balance, and swallowing deficits and outcome after traumatic brain injury: A multicenter analysis,” Archives of Physical Medicine and Rehabilitation, vol. 85, no. 8, pp. 1291–1297, 2004. View at Publisher · View at Google Scholar · View at Scopus
  23. C. M. Kim and J. J. Eng, “The relationship of lower-extremity muscle torque to locomotor performance in people with stroke,” Physical Therapy in Sport, vol. 83, pp. 49–57, 2003. View at Publisher · View at Google Scholar
  24. S. Nadeau, A. B. Arsenault, D. Gravel, and D. Bourbonnais, “Analysis of the clinical factors determining natural and maximal gait speeds in adults with a stroke,” American Journal of Physical Medicine & Rehabilitation, vol. 78, no. 2, pp. 123–130, 1999. View at Publisher · View at Google Scholar · View at Scopus
  25. S. L. Patterson, L. W. Forrester, M. M. Rodgers et al., “Determinants of walking function after stroke: differences by deficit severity,” Archives of Physical Medicine and Rehabilitation, vol. 88, no. 1, pp. 115–119, 2007. View at Publisher · View at Google Scholar · View at Scopus
  26. D. Drijkoningen, K. Caeyenberghs, C. Vander Linden, K. Van Herpe, J. Duysens, and S. P. Swinnen, “Associations between Muscle Strength Asymmetry and Impairments in Gait and Posture in Young Brain-Injured Patients,” Journal of Neurotrauma, vol. 32, no. 17, pp. 1324–1332, 2015. View at Publisher · View at Google Scholar · View at Scopus
  27. S. F. Tyson, M. Hanley, J. Chillala, A. Selley, and R. C. Tallis, “Balance disability after stroke,” Physical Therapy in Sport, vol. 86, no. 1, pp. 30–38, 2006. View at Publisher · View at Google Scholar · View at Scopus
  28. E. Tankisheva, A. Bogaerts, S. Boonen, H. Feys, and S. Verschueren, “Effects of intensive whole-body vibration training on muscle strength and balance in adults with chronic stroke: a randomized controlled pilot study,” Archives of Physical Medicine and Rehabilitation, vol. 95, no. 3, pp. 439–446, 2014. View at Publisher · View at Google Scholar · View at Scopus
  29. S. Rogan and L. Radlinger, “From no-go to go-go future training procedures for elderly,” Journal of Gerontology & Geriatric Research, vol. 5, no. 1, 2016. View at Google Scholar
  30. S. Rogan, J. Taeymans, L. Radlinger et al., “Effects of whole-body vibration on postural control in elderly: An update of a systematic review and meta-analysis,” Archives of Gerontology and Geriatrics, vol. 73, pp. 95–112, 2017. View at Google Scholar
  31. S. Rogan, L. Radlinger, H. Baur, D. Schmidtbleicher, R. A. de Bie, and E. D. de Bruin, “Sensory-motor training targeting motor dysfunction and muscle weakness in long-term care elderly combined with motivational strategies: a single blind randomized controlled study,” European Review of Aging and Physical Activity, vol. 13, no. 1, 2016. View at Google Scholar · View at Scopus
  32. S. Rogan, L. Radlinger, C. Portner-Burkhalter et al., “Feasibility study evaluating four weeks stochastic resonance whole-body vibration training with healthy female students,” International Journal of Kinesiology and Sports Science, vol. 1, pp. 1–9, 2013. View at Google Scholar
  33. S. Rogan, E. D. de Bruin, L. Radlinger et al., “Effects of whole-body vibration on proxies of muscle strength in old adults: A systematic review and meta-analysis on the role of physical capacity level,” European Review of Aging and Physical Activity, vol. 12, no. 1, 2015. View at Google Scholar · View at Scopus
  34. S. Rogan, R. Hilfiker, A. Schenk, A. Vogler, and J. Taeymans, “Effects of whole-body vibration with stochastic resonance on balance in persons with balance disability and falls history - a systematic review,” Research in sports medicine (Print), vol. 22, no. 3, pp. 294–313, 2014. View at Publisher · View at Google Scholar · View at Scopus
  35. M. Huang, C. Tang, and M. Y. Pang, “Use of whole body vibration in individuals with chronic stroke: Transmissibility and signal purity,” Journal of Biomechanics, vol. 73, pp. 80–91, 2018. View at Publisher · View at Google Scholar
  36. K.-S. Chan, C.-W. Liu, T.-W. Chen, M.-C. Weng, M.-H. Huang, and C.-H. Chen, “Effects of a single session of whole body vibration on ankle plantarflexion spasticity and gait performance in patients with chronic stroke: a randomized controlled trial,” Clinical Rehabilitation, vol. 26, no. 12, pp. 1087–1095, 2012. View at Publisher · View at Google Scholar · View at Scopus
  37. A. T. Silva, M. P. F. Dias, R. Calixto Jr. et al., “Acute effects of whole-body vibration on the motor function of patients with stroke: A randomized clinical trial,” American Journal of Physical Medicine & Rehabilitation, vol. 93, no. 4, pp. 310–319, 2014. View at Publisher · View at Google Scholar · View at Scopus
  38. T. K. Tihanyi, M. Horváth, G. Fazekas, T. Hortobágyi, and J. Tihanyi, “One session of whole body vibration increases voluntary muscle strength transiently in patients with stroke,” Clinical Rehabilitation, vol. 21, no. 9, pp. 782–793, 2007. View at Publisher · View at Google Scholar · View at Scopus
  39. S.-J. Choi, W.-S. Shin, B.-K. Oh, J.-K. Shim, and D.-H. Bang, “Effect of training with whole body vibration on the sitting balance of stroke patients,” Journal of Physical Therapy Science, vol. 26, no. 9, pp. 1411–1414, 2014. View at Publisher · View at Google Scholar · View at Scopus
  40. G. C. Lee, “Does whole-body vibration training in the horizontal direction have effects on motor function and balance of chronic stroke survivors? A preliminary study,” Journal of Physical Therapy Science, vol. 27, no. 4, pp. 1133–1136, 2015. View at Publisher · View at Google Scholar · View at Scopus
  41. J. Tihanyi, R. Di Giminiani, T. Tihanyi, G. Gyulai, L. Trzaskoma, and M. Horváth, “Low resonance frequency vibration affects strength of paretic and non-paretic leg differently in patients with stroke,” Acta Physiologica Hungarica, vol. 97, no. 2, pp. 172–182, 2010. View at Publisher · View at Google Scholar · View at Scopus
  42. I. J. W. Van Nes, A. C. H. Geurts, H. T. Hendricks, and J. Duysens, “Short-term effects of whole-body vibration on postural control in unilateral chronic stroke patients: preliminary evidence,” American Journal of Physical Medicine & Rehabilitation, vol. 83, no. 11, pp. 867–873, 2004. View at Publisher · View at Google Scholar · View at Scopus
  43. C. Brogrdh, U. B. Flansbjer, and J. Lexell, “No specific effect of whole-body vibration training in chronic stroke: a double-blind randomized controlled study,” Archives of Physical Medicine and Rehabilitation, vol. 93, no. 2, pp. 253–258, 2012. View at Publisher · View at Google Scholar · View at Scopus
  44. K. J. Hwang and Y. U. Ryu, “Whole body vibration may have immediate adverse effects on the postural sway of stroke patients,” Journal of Physical Therapy Science, vol. 28, no. 2, pp. 473–477, 2016. View at Publisher · View at Google Scholar · View at Scopus
  45. J. Lu, G. Xu, and Y. Wang, “Effects of whole body vibration training on people with chronic stroke: A systematic review and meta-analysis,” Topics in Stroke Rehabilitation, vol. 22, no. 3, pp. 161–168, 2015. View at Publisher · View at Google Scholar · View at Scopus
  46. P. J. Marín, C. M. Ferrero, H. Menéndez, J. Martín, and A. J. Herrero, “Effects of whole-body vibration on muscle architecture, muscle strength, and balance in stroke patients: a randomized controlled trial,” American Journal of Physical Medicine & Rehabilitation, vol. 92, no. 10, pp. 881–888, 2013. View at Publisher · View at Google Scholar · View at Scopus
  47. M. Y. Pang, R. W. Lau, and S. P. Yip, “The effects of whole-body vibration therapy on bone turnover, muscle strength, motor function, and spasticity in chronic stroke: a randomized controlled trial,” European Journal of Physical and Rehabilitation Medicine, vol. 49, pp. 439–450, 2013. View at Google Scholar
  48. I. J. W. van Nes, H. Latour, F. Schils, R. Meijer, A. Van Kuijk, and A. C. H. Geurts, “Long-term effects of 6-week whole-body vibration on balance recovery and activities of daily living in the postacute phase of stroke: a randomized, controlled trial,” Stroke, vol. 37, no. 9, pp. 2331–2335, 2006. View at Publisher · View at Google Scholar · View at Scopus
  49. L.-R. Liao, G. Y. F. Ng, A. Y. M. Jones, M.-Z. Huang, and M. Y. C. Pang, “Whole-Body Vibration Intensities in Chronic Stroke: A Randomized Controlled Trial,” Medicine & Science in Sports & Exercise, vol. 48, no. 7, pp. 1227–1238, 2016. View at Publisher · View at Google Scholar · View at Scopus
  50. R. W. K. Lau, S. P. Yip, and M. Y. C. Pang, “Whole-body vibration has no effect on neuromotor function and falls in chronic stroke,” Medicine & Science in Sports & Exercise, vol. 44, no. 8, pp. 1409–1418, 2012. View at Publisher · View at Google Scholar · View at Scopus
  51. M. Roelants, S. M. P. Verschueren, C. Delecluse, O. Levin, and V. Stijnen, “Whole-body-vibration-induced increase in leg muscle activity during different squat exercises,” The Journal of Strength and Conditioning Research, vol. 20, no. 1, pp. 124–129, 2006. View at Publisher · View at Google Scholar · View at Scopus
  52. D. J. Cochrane, S. R. Stannard, E. C. Firth, and J. Rittweger, “Acute whole-body vibration elicits post-activation potentiation,” European Journal of Applied Physiology, vol. 108, no. 2, pp. 311–319, 2010. View at Publisher · View at Google Scholar · View at Scopus
  53. C. J. De Ruiter and A. De Haan, “Temperature effect on the force/velocity relationship of the fresh and fatigued human adductor pollicis muscle,” Pflügers Archiv - European Journal of Physiology, vol. 440, no. 1, pp. 163–170, 2000. View at Publisher · View at Google Scholar · View at Scopus
  54. P. Arias, M. Chouza, J. Vivas, and J. Cudeiro, “Effect of whole body vibration in Parkinson's disease: a controlled study,” Movement Disorders, vol. 24, no. 6, pp. 891–898, 2009. View at Publisher · View at Google Scholar · View at Scopus
  55. C. Bosco, M. Iacovelli, O. Tsarpela et al., “Hormonal responses to whole-body vibration in men,” European Journal of Applied Physiology, vol. 81, no. 6, pp. 449–454, 2000. View at Publisher · View at Google Scholar · View at Scopus
  56. M. Cardinale, R. L. Soiza, J. B. Leiper, A. Gibson, and W. R. Primrose, “Hormonal responses to a single session of wholebody vibration exercise in older individuals,” British Journal of Sports Medicine, vol. 44, no. 4, pp. 284–288, 2010. View at Publisher · View at Google Scholar · View at Scopus
  57. K. H. Madou and J. B. Cronin, “The effects of whole body vibration on physical and physiological capability in special populations,” Hong Kong Physiotherapy Journal, vol. 26, pp. 24–38, 2008. View at Publisher · View at Google Scholar · View at Scopus
  58. S. Rogan, E. D. de Bruin, L. Radlinger et al., “Effects of whole-body vibration on proxies of muscle strength in old adults: a systematic review and meta-analysis on the role of physical capacity level,” European Review of Aging and Physical Activity, vol. 12, no. 1, 2015. View at Publisher · View at Google Scholar
  59. K. Herren and L. Radlinger, “Risks and side-effects of whole-body vibration training,” Physiotherapy, p. 97, 2011. View at Google Scholar
  60. K. Herren, C. Holz Hängärtner, A. Oberli et al., “Cardiovascular and metabolic strain during stochastic resonance therapy in stroke patients,” Physioscience, vol. 5, pp. 13–17, 2009. View at Google Scholar
  61. L.-R. Liao, G. Y. F. Ng, A. Y. M. Jones, and M. Y. C. Pang, “Cardiovascular stress induced by whole-body vibration exercise in individuals with chronic stroke,” Physical Therapy in Sport, vol. 95, no. 7, pp. 966–977, 2015. View at Publisher · View at Google Scholar · View at Scopus
  62. S. Rogan, D. Schmidtbleicher, and L. Radlinger, “Immediate effects after stochastic resonance whole-body vibration on physical performance on frail elderly for skilling-up training: a blind cross-over randomised pilot study,” Aging Clinical and Experimental Research, vol. 26, no. 5, pp. 519–527, 2014. View at Publisher · View at Google Scholar · View at Scopus
  63. A. F. J. Abercromby, W. E. Amonette, C. S. Layne, B. K. McFarlin, M. R. Hinman, and W. H. Paloski, “Vibration exposure and biodynamic responses during whole-body vibration training,” Medicine & Science in Sports & Exercise, vol. 39, no. 10, pp. 1794–1800, 2007. View at Publisher · View at Google Scholar · View at Scopus
  64. R. D. Prisby, M.-H. Lafage-Proust, L. Malaval, A. Belli, and L. Vico, “Effects of whole body vibration on the skeleton and other organ systems in man and animal models: what we know and what we need to know,” Ageing Research Reviews, vol. 7, no. 4, pp. 319–329, 2008. View at Publisher · View at Google Scholar · View at Scopus
  65. H. Sievänen, S. Karinkanta, P. Moisio-Vilenius, and J. Ripsaluoma, “Feasibility of whole-body vibration training in nursing home residents with low physical function: A pilot study,” Aging Clinical and Experimental Research, vol. 26, no. 5, pp. 511–517, 2014. View at Publisher · View at Google Scholar · View at Scopus
  66. L. B. Goldstein and G. P. Samsa, “Reliability of the National Institutes of Health Stroke Scale. Extension to non-neurologists in the context of a clinical trial,” Stroke, vol. 28, no. 2, pp. 307–310, 1997. View at Publisher · View at Google Scholar · View at Scopus
  67. J. Janša, T. Pogačnik, and P. Gompertz, “An evaluation of the Extended Barthel Index with acute ischemic stroke patients,” Neurorehabilitation and Neural Repair, vol. 18, no. 1, pp. 37–41, 2004. View at Publisher · View at Google Scholar · View at Scopus
  68. G. I. J. M. Kempen, L. Yardley, J. C. M. van Haastregt et al., “The short FES-I: a shortened version of the falls efficacy scale-international to assess fear of falling,” Age and Ageing, vol. 37, no. 1, pp. 45–50, 2008. View at Publisher · View at Google Scholar · View at Scopus
  69. M. Prosiegel, S. Böttger, T. Schenk et al., “Der erweiterte Barthel-Index (EBI)–eine neue Skala zur Erfassung von Fähigkeitsstörungen bei neurologischen Patienten,” Neurologie & Rehabilitation, vol. 1, pp. 7–13, 1996. View at Google Scholar
  70. H. J. Hermens, B. Freriks, R. Merletti et al., “European recommendations for surface electromyography,” Roessingh Research and Development, vol. 8, pp. 13–54, 1999. View at Google Scholar
  71. C. Mebes, A. Amstutz, G. Luder et al., “Isometric rate of force development, maximum voluntary contraction, and balance in women with and without joint hypermobility,” Arthritis Care & Research, vol. 59, no. 11, pp. 1665–1669, 2008. View at Publisher · View at Google Scholar · View at Scopus
  72. P. Bessou, P. Dupui, R. Montoya, and B. Pages, “Simultaneous recording of longitudinal displacements of both feet during human walking,” Journal de Physiologie, vol. 83, no. 2, pp. 102–110, 1988. View at Google Scholar · View at Scopus
  73. L.-R. Liao, M. Huang, F. M. H. Lam, and M. Y. C. Pang, “Effects of whole-body vibration therapy on body functions and structures, activity, and participation poststroke: A systematic review,” Physical Therapy in Sport, vol. 94, no. 9, pp. 1232–1251, 2014. View at Publisher · View at Google Scholar · View at Scopus
  74. X. Yang, P. Wang, C. Liu, C. He, and J. D. Reinhardt, “The effect of whole body vibration on balance, gait performance and mobility in people with stroke: A systematic review and meta-analysis,” Clinical Rehabilitation, vol. 29, no. 7, pp. 627–638, 2015. View at Publisher · View at Google Scholar · View at Scopus
  75. M. Cardinale and J. Lim, “The acute effects of two different whole body vibration frequencies on vertical jump performance,” Medicina dello Sport, vol. 56, no. 4, pp. 287–292, 2003. View at Google Scholar · View at Scopus
  76. S. Torvinen, H. Sievänen, T. A. H. Järvinen, M. Pasanen, S. Kontulainen, and P. Kannus, “Effect of 4-min vertical whole body vibration on muscle performance and body balance: a randomized cross-over study,” International Journal of Sports Medicine, vol. 23, no. 5, pp. 374–379, 2002. View at Publisher · View at Google Scholar · View at Scopus
  77. P. J. Marín, D. Bunker, M. R. Rhea, and F. N. Ayllón, “Neuromuscular activity during whole-body vibration of different amplitudes and footwear conditions:Implications for prescription of vibratory stimulation,” The Journal of Strength and Conditioning Research, vol. 23, no. 8, pp. 2311–2316, 2009. View at Publisher · View at Google Scholar · View at Scopus
  78. M. A. Freeman and B. Wyke, “The innervation of the ankle joint. An anatomical and histological study in the cat.,” Cells Tissues Organs, vol. 68, no. 3, pp. 321–333, 1967. View at Publisher · View at Google Scholar · View at Scopus
  79. J. Kessler, L. Radlinger, H. Baur, and S. Rogan, “Effect of stochastic resonance whole body vibration on functional performance in the frail elderly: A pilot study,” Archives of Gerontology and Geriatrics, vol. 59, no. 2, pp. 305–311, 2013. View at Publisher · View at Google Scholar · View at Scopus
  80. S. Rogan, L. Radlinger, D. Schmidtbleicher, R. A. de Bie, and E. D. de Bruin, “Preliminary inconclusive results of a randomised double blinded cross-over pilot trial in long-term-care dwelling elderly assessing the feasibility of stochastic resonance whole-body vibration,” European Review of Aging and Physical Activity, vol. 12, no. 1, 2015. View at Google Scholar · View at Scopus
  81. M. H. de Groot, S. J. Phillips, and G. A. Eskes, “Fatigue associated with stroke and other neurologic conditions: implications for stroke rehabilitation,” Archives of Physical Medicine and Rehabilitation, vol. 84, no. 11, pp. 1714–1720, 2003. View at Publisher · View at Google Scholar · View at Scopus
  82. B. H. Dobkin, “Fatigue versus activity-dependent fatigability in patients with central or peripheral motor impairments,” Neurorehabilitation and Neural Repair, vol. 22, no. 2, pp. 105–110, 2008. View at Publisher · View at Google Scholar · View at Scopus
  83. J. L. Ingles, G. A. Eskes, and S. J. Phillips, “Fatigue after stroke,” Archives of Physical Medicine and Rehabilitation, vol. 80, no. 2, pp. 173–178, 1999. View at Publisher · View at Google Scholar · View at Scopus
  84. A. Schillinger and F. Becker, “Fatigue/utmattelse etter traumatisk hjerneskade og hjerneslag,” Tidsskrift for Den norske legeforening, vol. 135, no. 4, pp. 331–335, 2015. View at Publisher · View at Google Scholar
  85. F. Staub and J. Bogousslavsky, “Fatigue after stroke: a major but neglected issue,” Cerebrovascular Disease, vol. 12, no. 2, pp. 75–81, 2001. View at Publisher · View at Google Scholar · View at Scopus
  86. U. B. Flansbjer, A. M. Holmbäck, D. Downham, and J. Lexell, “What change in isokinetic knee muscle strength can be detected in men and women with hemiparesis after stroke?” Clinical Rehabilitation, vol. 19, no. 5, pp. 514–522, 2005. View at Publisher · View at Google Scholar · View at Scopus
  87. E.-T. Choi, Y.-N. Kim, W.-S. Cho, and D.-K. Lee, “The effects of visual control whole body vibration exercise on balance and gait function of stroke patients,” Journal of Physical Therapy Science, vol. 28, no. 11, pp. 3149–3152, 2016. View at Publisher · View at Google Scholar · View at Scopus
  88. J. Merkert, S. Butz, R. Nieczaj, E. Steinhagen-Thiessen, and R. Eckardt, “Combined whole body vibration and balance training using Vibrosphere®. Improvement of trunk stability, muscle tone, and postural control in stroke patients during early geriatric rehabilitation,” Zeitschrift für Gerontologie und Geriatrie, vol. 44, no. 4, pp. 256–261, 2011. View at Publisher · View at Google Scholar · View at Scopus
  89. C. Guo, X. Mi, S. Liu et al., “Whole body vibration training improves walking performance of stroke patients with knee hyperextension: A randomized controlled pilot study,” CNS and Neurological Disorders - Drug Targets, vol. 14, no. 9, pp. 1110–1115, 2015. View at Publisher · View at Google Scholar · View at Scopus
  90. P.-D. Petit, M. Pensini, J. Tessaro, C. Desnuelle, P. Legros, and S. S. Colson, “Optimal whole-body vibration settings for muscle strength and power enhancement in human knee extensors,” Journal of Electromyography & Kinesiology, vol. 20, no. 6, pp. 1186–1195, 2010. View at Publisher · View at Google Scholar · View at Scopus
  91. R. Dickstein, Z. Dvir, E. Ben Jehosua, M. Rois, and T. Pillar, “Automatic and voluntary lateral weight shifts in rehabilitation of hemiparetic patients,” Clinical Rehabilitation, vol. 8, no. 2, pp. 91–99, 1994. View at Publisher · View at Google Scholar · View at Scopus
  92. S. W. Kong, Y. W. Jeong, and J. Y. Kim, “Correlation between balance and gait according to pelvic displacement in stroke patients,” Journal of Physical Therapy Science, vol. 27, no. 7, pp. 2171–2174, 2015. View at Publisher · View at Google Scholar · View at Scopus
  93. M. Furlan, G. Marchai, F. Viader, J.-M. Derlon, and J.-C. Baron, “Spontaneous neurological recovery after stroke and the fate of the ischemic penumbra,” Annals of Neurology, vol. 40, no. 2, pp. 216–226, 1996. View at Publisher · View at Google Scholar · View at Scopus
  94. M. Newman, “The process of recovery after hemiplegia,” Stroke, vol. 3, no. 6, pp. 702–710, 1972. View at Publisher · View at Google Scholar · View at Scopus
  95. R. J. Nudo, “Recovery after brain injury: mechanisms and principles,” Frontiers in Human Neuroscience, vol. 7, article 887, 2013. View at Publisher · View at Google Scholar · View at Scopus
  96. D. T. Wade, V. A. Wood, and R. L. Hewer, “Recovery after stroke--the first 3 months.,” Journal of Neurology, Neurosurgery & Psychiatry, vol. 48, no. 1, pp. 7–13, 1985. View at Publisher · View at Google Scholar