The effect of whole body vibration exposure on balance and functional mobility in older adults: a systematic review and meta-analysis

Effect of 10-Week Whole-Body Vibration Training on Falls and Physical Performance in Older Adults: A Blinded, Randomized, Controlled Clinical Trial with 1-Year Follow-Up

Whole-body vibration training (WBV) training has shown positive effects on bone strength, muscle strength, and balance, but the evidence on fall prevention is not yet persuasive. This study aimed to evaluate the effectiveness of WBV training in preventing falls and improving physical performance among older adults at fall risk. The study was an assessor- and participant-blinded, randomized, and controlled 10-week training trial with a 10-month follow-up. One hundred and thirty older adults (mean age 78.5 years, 75% women) were randomly allocated into the WBV group (n = 68) and the low-intensity wellness group (n = 62). Falls were prospectively collected using monthly returned and verified diaries. Physical performance was evaluated at baseline before randomization, after the intervention, and follow-up with established methods. The data were analyzed on an intention-to-treat basis. Negative binomial regression was used to estimate the incidence rate ratios for falls, and Cox regression models were used to calculate the hazard ratios for fallers. Between-group differences in physical performance were estimated by generalized linear mixed models. The retention rate was 93%, and the mean adherence to the WBV training was 88% and 86% to the wellness training. Sixty-eight participants fell at least once, and there were 156 falls in total. In the WBV group, the incidence rate of falls was 1.5 (95% confidence interval 0.9 to 2.5) compared to the wellness group (p = 0.11). The hazard ratio for fallers in the WBV group was 1.29 (0.78 to 2.15) (p = 0.32). There was no between-group difference in physical performance after the training period, but by the end of the follow-up, WBV-related benefits appeared. The chair-rising capacity was maintained in the WBV group, while the benefit disappeared in the wellness group (p = 0.004). Also, the 0.5-point difference in short physical performance battery (SPPB) score favored WBV training (p = 0.009). In conclusion, progressive side-alternating WBV training was feasible and well-tolerated among fall-prone older adults. During the one-year follow-up, WBV training was associated with improved physical performance but did not prevent falls compared to chair-based group exercises.

Intervention Hypothesis for Training with Whole-Body Vibration to Improve Physical Fitness Levels: An Umbrella Review

Whole-body vibration (WBV) is a training modality, and it seems to be a safe and efficient exercise especially to improve different aspects of physical fitness in different populations. The protocols for WBV are still not standardized. The difficulty in comparing the data confuses the real efficacy of this instrument. Consequently, the objective of this umbrella review is to analyze the protocols previously adopted and eventually to propose a standard operating procedure for WBV training. Systematic review and meta-analysis of randomized controlled trials on WBV were searched on the electronic databases PubMed, Web of Science, and Scopus until 18 March 2024. A quality assessment of the studies included has been performed. A total of 20 studies were included in this umbrella review and frequency, magnitude, and amplitude intensity data were recorded. Detailed information about the protocols (static or dynamic exercises, barefoot or with shoes, intensity duration, weekly frequency, and vibration characteristics) was also collected. WBV presents widely different protocols. Consequently, a standard operating procedure has not been proposed for WBV training. A hypothesis of intervention was instead written in which parameters for frequency, amplitude, acceleration, and training mode were proposed.

Whole-Body Vibration to Improve Physical Function Parameters in Nursing Home Residents Older Than 80 Years: A Systematic Review With Meta-Analysis

OBJECTIVE

Loss of functional independence is more likely in older adults who reside in an institution as a consequence of a decline in muscle mass and a loss of force production capacity. The aim of this review was to assess the effect of whole-body vibration (WBV) interventions on the strength, balance, and mobility of nursing home residents older than 80 years.

METHODS

An electronic search in MEDLINE, Scopus, and CINAHL databases was conducted. Randomized controlled trials that involved nursing home residents older than 80 years, that investigated WBV interventions compared with nonintervention, usual care, or placebo, and that measured physical function outcomes including strength, balance, gait, and mobility were included. Risk of bias was assessed by 2 reviewers using the Physiotherapy Evidence Database scale. The standardized mean differences (SMD) between the experimental and control groups were calculated with a random-effects model for each outcome, and subgroup analysis was conducted for different outcomes.

RESULTS

In total, 2864 articles were identified; of these, 14 randomized controlled trials met the inclusion criteria. The meta-analysis revealed that WBV significantly increased the lower limb muscle strength (SMD = 0.59; 95% CI = 0.16 to 1.03), mobility (SMD = 0.45; 95% CI = 0.10 to 0.81), gait score (SMD = 0.26; 95% CI = 0.01 to 0.51), balance (SMD = 0.41; 95% CI = 0.01 to 0.81), and physical performance (SMD = 1.33; 95% CI = 0.33 to 2.33).

CONCLUSION

WBV may be an effective intervention to improve the strength, balance, mobility, walking ability, and physical performance of older nursing home residents.

IMPACT

WBV presents a safe, accessible alternative for improving health in this vulnerable population, warranting further research and integration into health care practices.

The Efficacy of Whole-Body Vibration in Managing Postburn Victims' Complications: A Systematic Review

Burn injury is a complicated traumatic event with both systemic and local consequences. These complications include long periods of bed rest, pain, muscle weakness, vitamin D deficiency, and bone mineral density loss. Whole-body vibration demonstrated effectiveness in improving muscle power and bone mineral density in various musculoskeletal populations. This systematic review of randomized controlled trials aims to assess evidence for the effectiveness of using whole-body vibration on postburn survivors with at least 1% total body surface area on sensory and motor outcomes. A systematic search was conducted across six databases, which are, PubMed, Cochrane, PEDro, Scopus, Web of Science, and Google Scholar, from inception till March 2022. Retrieved studies were screened by title and abstract and full-text in two stages using Rayyan web-based. Included studies were assessed for risk of bias using the Cochrane risk of bias tool ROB 2.0. Six randomized controlled trials with 203 participants were included. Five of the included studies demonstrated an overall high risk of bias. Compared to conventional physiotherapy programs, whole-body vibration demonstrated improvement in functional mobility and balance using timed up and go and Biodex balance assessment, respectively. However, there were no differences between whole-body vibration and conventional physiotherapy program alone in bone mineral density and muscle power. Although the current evidence of whole-body vibration is limited, whole-body vibration combined with traditional physical therapy programs may improve functional mobility and balance in postburn survivors compared to physical therapy programs alone.

Sensorimotor integration is affected by acute whole-body vibration: a coherence study

Introduction: Several whole-body vibration (WBV) effects on performance have been related to potential changes in the neural drive, motor unit firing rate, and sensorimotor integration. In the present paper, motor unit coherence analysis was performed to detect the source of neural modulation based on the frequency domain. Methods: Thirteen men [25 ± 2.1 years; Body Mass Index (BMI) = 23.9 ± 1.3 kg m2; maximal voluntary force (MVF): 324.36 ± 41.26 N] performed sustained contractions of the Tibialis Anterior (TA) at 10%MVF before and after acute WBV. The vibrating stimulus was applied barefoot through a platform to target the TA. High-Density surface Electromyography (HDsEMG) was used to record the myoelectrical activity of TA to evaluate coherence from motor unit cumulative spike-trains (CSTs). Results: Mean coherence showed a significant decrease in the alpha and low-beta bandwidths (alpha: from 0.143 ± 0.129 to 0.132 ± 0.129, p = 0.035; low-beta: from 0.117 ± 0.039 to 0.086 ± 0.03, p = 0.0001), whereas no significant changes were found in the other ones (p > 0.05). The discharge rate (DR) and the Force Covariance (CovF%) were not significantly affected by acute WBV exposure (p > 0.05). Discussion: According to the significant effects found in alpha and low-beta bandwidths, which reflect sensorimotor integration parameters, accompanied by no differences in the DR and CovF%, the present results underlined that possible neural mechanisms at the base of the previously reported performance enhancements following acute WBV are likely based on sensorimotor integration rather than direct neural drive modulation.

Effects of Physical Activity Interventions on Strength, Balance and Falls in Middle-Aged Adults: A Systematic Review and Meta-Analysis

BACKGROUND

Weak lower body strength and balance impairments are fundamental risk factors for mobility impairments and falls that can be improved by physical activity (PA). Previous meta-analyses have focused on these risk factors in adults aged ≥ 65 years. Yet, the potential of PA for improving these risk factors in middle-aged populations has not been systematically investigated. This systematic review and meta-analysis aim to examine the effect of general and structured PA on lower limb strength, postural balance and falls in middle-aged adults.

METHODS

A computerized systematic literature search was conducted in the electronic databases MEDLINE, CINAHL, Web of Science and Cochrane Library. PA intervention types were classified according to the ProFaNE taxonomy. Randomized controlled trials exploring the effects of PA on strength (e.g., leg press one-repetition-maximum), balance (e.g., single limb stance) and falls (e.g., fall rates) in adults aged 40-60 years were systematically searched and included in a network analysis. Moderator analyses were performed for specific subgroups (age, sex, low PA). The methodological quality of the included studies was assessed using the Physiotherapy Evidence Database (PEDro) Scale.

RESULTS

Out of 7170 articles screened, 66 studies (median PEDro score 5) with 3387 participants were included. Strong, significant effects on muscle strength were found for strength (SMD = 1.02), strength-aerobic (SMD = 1.41), strength-endurance (SMD = 0.92) and water-based (SMD = 1.08) training (52 studies, I² = 79.3%). Strength training (SMD = 1.16), strength-aerobic (SMD = 0.98) and 3D training (SMD = 1.31) improved postural balance (30 studies, I² = 88.1%). Moderator analyses revealed significant effects of specific intervention types on certain subgroups and subdomains of strength and balance. No studies were found measuring falls.

CONCLUSIONS

Structured PA interventions in middle-aged adults improve strength and balance outcomes related to functional impairments and falls. Strength training increases both strength and balance and can be recommended to prevent age-related functional decline. However, the interpretability of the results is limited due to considerable heterogeneity and the overall low methodological quality of the included studies. Long-term trials are needed to determine the preventive potential of PA on strength, balance and falls. This meta-analysis may inform guidelines for tailored training during middle age to promote healthy aging. Prospero registration: CRD42020218643.

The acute effects of whole-body vibration on motor unit recruitment and discharge properties

Introduction: several studies have reported improved neuromuscular parameters in response to whole-body vibration (WBV). This is likely achieved by modulation of the central nervous system (CNS). Reduced recruitment threshold (RT), which is the % of Maximal Voluntary Force (%MVF) at which a given Motor Unit (MU) is recruited, may be responsible for the force/power improvements observed in several studies. Methods: 14 men (25 ± 2.3 years; BMI = 23.3 ± 1.5 kg m² MVF: 319.82 ± 45.74 N) performed trapezoidal isometric contractions of the tibialis anterior (TA) at 35-50-70 %MVF before and after three conditions: WBV, STAND (standing posture), and CNT (no intervention). The vibration was applied through a platform for targeting the TA. High-density surface electromyography (HDsEMG) recordings and analysis were used to detect changes in the RT and Discharge Rate (DR) of the MUs. Results: Mean motor unit recruitment threshold (MURT) reached 32.04 ± 3.28 %MVF before and 31.2 ± 3.72 %MVF after WBV, with no significant differences between conditions (p > 0.05). Additionally, no significant changes were found in the mean motor unit discharge rate (before WBV: 21.11 ± 2.94 pps; after WBV: 21.19 ± 2.17 pps). Discussion: The present study showed no significant changes in motor unit properties at the base of neuromuscular changes documented in previous studies. Further investigations are needed to understand motor unit responses to different vibration protocols and the chronic effect of vibration exposure on motor control strategies.

Effects of whole-body vibration training with different frequencies on the balance ability of the older adults: a network meta-analysis

Purpose: To compare the effects of whole-body vibration training (WBVT) with different frequencies on the balance ability of older adults. Methods: Randomized controlled trials (RCTs) on the WBVT interventions on balance ability in older adults were searched through PubMed, Web of Science, The Cochrane Library, ProQuest, Embase, Opengrey, China National Knowledge Infrastructure (CNKI), Wanfang, and China Science and Technology Journal Database (CSTJ) databases from the establishment of the database to August 2022, and all literature that met the PICOS (Participants, Intervention, Comparison, Outcomes, Study design) criteria were enrolled. Two reviewers screened and assessed the methodological quality of the included literature according to the physiotherapy evidence database (PEDro) scale criteria. Statistical analysis was performed using Stata 14.0 software after data extraction. Results: Twenty-five RCTs with a total of 1267 subjects were finally included. The results of the pairwise comparison of the Network Meta-analysis showed that the Timed Up and Go Test (TUGT) values of Low-frequency whole-body vibration training (LF-WBVT) was lower than the placebo and traditional rehabilitation groups, and the difference was statistically significant [WMD = -1.37, 95% CI (-2.53, -0.20)] [WMD = -1.84, 95% CI(-3.17,-0.51)]. The Five-repetition Sit-to-Stand Test (5STS) values of LF-WBVT, Medium-frequency whole-body vibration training (MF-WBVT), and High-frequency whole-body vibration training (HF-WBVT) were lower than the placebo and traditional rehabilitation groups, but none of them were statistically significant. In addition, the TUGT and 5STS values of HF-WBVT had a tendency to be lower than those of LF-WBVT and MF-WBVT, but neither of them was statistically different. The cumulative probability ranking results of both TUGT and 5STS showed that HF-WBVT was the best protocol. Conclusion: Current evidence shows that HF-WBVT may be the best protocol for improving balance in older adults. Due to the study's limitations, the conclusion obtained in this study still needs to be further confirmed by more high-quality studies. Systematic Review Registration: [https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42021250405].

Short-term effects of side-alternating Whole-Body Vibration on cognitive function of young adults

Recent research in rodents and humans revealed that Whole-Body Vibration (WBV) is beneficial for cognitive functions. However, the optimal WBV conditions are not established: contrary to vertical WBV, side-alternating WBV was not investigated before. The present study investigated the short-term effects of side-alternating WBV in standing and sitting posture on specific cognitive function of young adults. We used a balanced cross-over design. Sixty healthy young adults (mean age 21.7 ± 2.0 years, 72% female) participated. They were exposed to three bouts of two-minute side-alternating WBV (frequency 27 Hz) and three control conditions in two different sessions. In one session a sitting posture was used and in the other session a standing (semi-squat) posture. After each condition selective attention and inhibition was measured with the incongruent condition of the Stroop Color-Word Interference Test. WBV significantly (p = 0.026) improved selective attention and inhibition in the sitting posture, but not in the standing posture. The sitting posture was perceived as more comfortable, joyous and less exhaustive as compared to the standing posture. This study demonstrated that side-alternating WBV in sitting posture improves selective attention and inhibition in healthy young adults. This indicates that posture moderates the cognitive effect of WBV, although the effects are still small. Future studies should focus on the working mechanisms and further optimization of settings, especially in individuals who are unable to perform active exercise.

Can two multimodal psychomotor exercise programs improve attention, affordance perception, and balance in community dwellings at risk of falling? A randomized controlled trial

BACKGROUND

Falls are associated with cognitive and physical function deterioration. Attention decline, inaccurate affordance perception, and balance impairment are considered to be risk factors for falls. Furthermore, few studies have reported psychomotor intervention as a fall prevention program. This study aimed to investigate the effects of two multimodal programs on attention, perceptual and stepping-forward boundaries, and balance in community-dwelling older adults at risk of falling.

METHODS

Fifty-one community-dwelling older adults were recruited to participate in a 24-week randomized controlled trial. Participants (75.4 ± 5.6 years) were randomly assigned to one of three groups: the 1) multimodal psychomotor program [EG1], 2) combined program (multimodal psychomotor program + whole-body vibration program) [EG2], and 3) control group. Participants were assessed at baseline, at post-intervention, and after a 12-week no-intervention follow-up period.

RESULTS

The within-group comparisons showed significant improvements in attention and balance in EG1 and EG2 after the intervention (p <  0.05). The magnitudes of the treatment effects were similar in both EGs, ranging from medium to large. Decreases in the fall rate were also observed in EG1 (- 44.2%) and EG2 (- 63.0%) (p <  0.05). During the follow-up period, these improvements in attention were maintained, while those in balance were reversed in both EGs. No significant differences between groups were found.

CONCLUSIONS

These study results suggest that both multimodal exercise programs were effective for fall prevention and were well tolerated by the participants. Specifically, EG1 and EG2 showed identical improvements in attention, and EG2 presented a slightly larger enhancement in balance and a larger decrease in the fall rate. Our findings demonstrate the benefits of maintaining the psychomotor intervention program by itself or in combination with the whole-body vibration program to prevent cognitive and physical function deterioration.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03446352 . Date of registration: February 26, 2018.

Favorable Effects of 24-Week Whole-Body Vibration on Glycemic Control and Comprehensive Diabetes Therapy in Elderly Patients with Type 2 Diabetes

BACKGROUND

Elderly patients with type 2 diabetes (T2DM) are vulnerable to treatment-inducible hypoglycemia, falls, and depressive symptoms. Although it is challenging for elderly patients to adhere to regular exercise, its positive effect on functional ability, glycemic control, and mental wellness offers comprehensive diabetes treatment. In the present study, we aimed to investigate a novel exercise approach for the elderly, focusing on whole-body vibration (WBV).

METHODS

This retrospective cohort study was conducted in a primary-care setting at a medical fitness center affiliated with the incorporated medical institution of THY (TOTAL HEALTH YARD). Fourteen (WBV group) and 12 (control group) elderly patients with T2DM undergoing and not undergoing our WBV program, respectively, for > 6 months were analyzed. Primary endpoints were the functional ability changes, evaluated by Timed Up and Go (TUG), Sit-to-Stand test (SST), gait length, and grip test. Secondary endpoints were global glycemic control and questionnaires, namely the Diabetes Treatment Satisfaction Questionnaire (DTSQ) and Geriatric Depression Scale (GDS). All records of exercise adherence and any adverse events were followed.

RESULTS

Significant improvements in TUG and SST were found only in the WBV group [TUG: 7.1 ± 0.9, 7.1 ± 0.8 to 7.0 ± 1.0, 6.6 ± 0.9 (s), P = 0.63, 0.01; SST: 10.4 ± 1.9, 11.3 ± 2.4 to 9.7 ± 2.3, 9.5 ± 2.1 (s), P = 0.62, P < 0.01, control vs. WBV group, respectively]. The WBV group demonstrated significant improvement of hemoglobin A1C levels (7.2 ± 0.8 to 6.9 ± 0.5, P < 0.01) and DTSQ and GDS scores, while the control group did not. There were no hypoglycemic events during the study. The WBV program adherence was 93.3 ± 8.0%.

CONCLUSION

We demonstrated the favorable effect of WBV training on balance, diabetes treatment, and mood. Therefore, WBV training can be proposed as comprehensive therapy in a safe manner and potentially has a positive effect on health-related quality of life in elderly patients with T2DM.

Effectiveness of whole-body vibration or biofeedback postural training as an add-on to vestibular exercises rehabilitation therapy in chronic unilateral vestibular weakness: A randomized controlled study

BACKGROUND

The efforts to achieve better functional results in vestibular rehabilitation have been continued by using different visual and somatosensory stimuli for a long time. Whole-body vibration (WBV) is a mechanical vertical stimulation that provides high frequency vibration stimulus to the proprioceptive receptors. Biofeedback provides continuous information to the subject regarding postural changes. These techniques may aid to improve vestibular rehabilitation.

OBJECTIVE

We aimed to investigate the effect of adding WBV or biofeedback postural training (BPT) to standard rehabilitation exercises in patients with chronic unilateral vestibular weakness.

METHODS

Ninety patients were randomized into three groups. Group 1 had WBV and Group 2 BPT in addition to the standard rehabilitation exercises. Group 3 only carried out the home-based exercises and served as the control. Outcome measures such as static posturography, Berg Balance Scale, Timed Up-and-Go test, Visual Analog Scale, and Dizziness Handicap Inventory (DHI) were used for comparison.

RESULTS

Statistically significant gains were achieved in all groups with all parameters at the end of treatment when compared to baseline (p < 0.05). The patients in Group 1 (WBV), however, were significantly better than those in Groups 2 and 3 at the static posturographic stability score, Berg Balance Scale, and DHI (p < 0.05).

CONCLUSION

Adding WBV to a rehabilitation program may be an effective strategy to improve postural stability and achieve better physical, functional and emotional outcomes.

EFFECTS OF WHOLE-BODY VIBRATION ON MUSCLE STRENGTH, BALANCE AND FUNCTIONAL MOBILITY IN PATIENTS WITH MULTIPLE SCLEROSIS: A SYSTEMATIC REVIEW AND META-ANALYSIS

Multiple sclerosis (MS) is a type of degenerative syndrome that causes impaired physical function, decreased walking, imbalance, spasticity, sensory impairment, muscle weakness, fatigue, and demyelination of the central nervous system. The purpose of this review was to critically examine available studies on the efficacy of whole-body vibration (WBV) in patients with MS during rehabilitation training to increase strength, balance, and functional mobility. An organized literature search was performed on databases from various sources, including PubMed, MEDLINE, CINAHL, and EMBASE, to identify relevant randomized clinical trials (RCTs). Eight studies were finally selected based on exclusion and inclusion criteria. Attempts were made to identify factors affecting the improvement in muscle strength, balance, and functional mobility in MS patients as a result of WBV. A meta-analysis was performed if two or more studies measured the same outcome of interest. The meta-analysis found that the WBV intervention showed significant improvement over control groups in Body Balance Score (BBS) (MD = [Formula: see text]2.86, 95%CI = [Formula: see text]5.29 [Formula: see text] 0.43; [Formula: see text], [Formula: see text], heterogeneity ([Formula: see text]%). In addition, walking endurance (6MWT) favored control groups over WBV intervention (MD [Formula: see text], 95%CI [Formula: see text][Formula: see text] 99.41; [Formula: see text] = 2.97, [Formula: see text]). Timed-Up-and-Go Test (TUG) and Expanded Disability Status Scale (EDSS) ([Formula: see text]) had no significant effect on WBV. Restoration of balance and functional mobility appeared to respond better to WBV with additional exercise protocols compared to WBV alone. Although there is evidence of an overall effect of WBV on strength and some measures of balance and mobility, its impact remains inconclusive. Therefore, more robust RCTs examining exposure to WBV on balance and functional mobility in patients with MS are warranted.

Effects of vibration therapy on muscle mass, muscle strength and physical function in older adults with sarcopenia: a systematic review and meta-analysis

Background

Sarcopenia, a progressive loss of muscle mass and function with advancing age, is a prevalent condition among older adults. As most older people are too frail to do intensive exercise and vibration therapy has low risk and ease of participation, it may be more readily accepted by elderly individuals. However, it remains unclear whether vibration therapy would be effective among older adults with sarcopenia. This systematic review and meta-analysis examined the effect of vibration therapy including local vibration therapy and whole-body vibration therapy, for enhancing muscle mass, muscle strength and physical function in older people with sarcopenia.

Methods

A systematic literature search was conducted in March 2019 in the following 5 electronic databases: PubMed, CINAHL, Embase, PEDro, and the Cochrane Central Register of Controlled Trials, with no restriction of language or the year of publication. Randomized controlled trials and quasi-experimental studies examining effects of vibration therapy on muscle mass, muscle strength or physical function in older adults with sarcopenia were included in this systematic review. Two reviewers independently assessed the methodological quality of the selected studies.

Results

Of the 1972 identified studies, seven publications from six studies involving 223 participants were included in this systematic review. Five of them conducted whole-body vibration therapy, while two conducted local vibration therapy. A meta-analysis of randomized controlled studies indicated that muscle strength significantly increased after whole-body vibration therapy (SMD 0.69, 95% CI 0.28 to 1.11, I² = 0%, P = 0.001) and local vibration therapy (SMD 3.78, 95% CI 2.29 to 5.28, P < 0.001). Physical performance measured by the sit-to-stand test and the timed-up-and-go test were significantly improved after the intervention (SMD -0.79, 95% CI − 1.21 to − 0.37, I² = 0%, P < 0.001) and SMD -0.83, 95% CI − 1.56 to − 0.11, I² = 64%, P = 0.02, respectively).

Conclusion

Vibration therapy could be a prospective strategy for improving muscle strength and physical performance in older adults with sarcopenia. However, due to the limited number of the included studies, caution is needed when interpreting these results. More well-designed, large sample size studies should be conducted to further explore and validate the benefits of vibration therapy for this population.

Immediate Effects of Local Vibration and Whole-body Vibration on Postural Control in Patients with Ataxia: an Assessor-Blind, Cross-over randomized trial

Vibration interventions are used in neurorehabilitation to improve postural control in recent years. Little is known about the immediate effects of vibration interventions on postural control in patients with ataxia. The aim of this study is to investigate and compare the immediate effects of local vibration (LV) and whole-body vibration (WBV) on postural control in patients with ataxia. This study was designed as cross-over, single blind randomized clinical trial. Twenty-one patients with ataxia met the inclusion criteria. LV (frequency, 80 Hz; amplitude, 1 mm) and WBV (30 Hz, 2 mm) were applied to all patients. There was a 1-week washout time between interventions. Each patient was assessed 3 times: pre-intervention and 1 and 60 min post-intervention. The assessor was blinded to the interventions. Outcome measures were limits of stability (LoS), and postural sways (Bertec Balance Check Screener), gait parameters (GAITRite), and static balance (one-leg stance test). Twenty patients completed both interventions. The mean patient age was 39.43 ± 9.67 years. LV increased the left-LoS post-vibration (1 and 60 min post) more than WBV did (p ˂ 0.05). LV increased the LoS stability score and the base of support at 1 min post-vibration, while WBV decreased them (p ˂ 0.05). This study demonstrated different immediate effects of a single session of LV versus WBV and showed that LV has better effects on postural control in patients with ataxia. ClinicalTrials.gov. nr NCT04183647.

Acute whole-body vibration reduces post-activation depression in the triceps surae muscle

PURPOSE

Acute whole-body vibration (WBV) is known to enhance neuromuscular activation. Especially mechanisms which act presynaptically are discussed to be involved in this modulation, but evidence is still limited. Therefore, this study aimed to investigate if 2 min of WBV might impact the premotoneuronal mechanism of post-activation depression (PAD).

METHODS

PAD in m. soleus was assessed by paired-pulse stimulation in 28 healthy participants prior, 2 min, 4 min and 10 min after 2 min of side-alternating WBV (10 Hz, 2 mm). Methodologies involved electromyography (m. soleus, m. tibialis anterior) and goniometric recordings (ankle, knee joint). H-reflexes were elicited with peripheral nerve stimulation and assessed by means of conditioned H-reflexes (ISI 1 s, H_cond) versus control H-reflexes (ISI₁₀, H).

RESULTS

H_cond/H was significantly enhanced by +55% (2 min), +32% (4 min) and +35% (10 min) following WBV (P < 0.05). Baseline muscle activity and joint positions were shown to be reliable (Cronbach's α values >0.990) throughout the testing procedure.

CONCLUSION

Vibratory-induced spinal inhibition is accompanied by diminished PAD at the presynaptic terminals which interconnect the Ia afferents with the α-motoneuron. Functionally, the PAD reduction might explain enhanced motor performance following vibration therapy, but future studies will be needed to verify this assumption.

Acute Effects of a Whole Body Vibration Session on the Vibration Perception Threshold in Patients with Type 2 Diabetes Mellitus

BACKGROUND

Type 2 Diabetes Mellitus (T2DM) is a chronic disease that affects millions of people, and according to the International Diabetes Federation, 46.5% of people have undiagnosed diabetes. One of the most common complications of diabetes mellitus is loss of peripheral sensation. Whole Body Vibration (WBV) is a therapy, and it would be interesting to know if it can be considered as a training method to improve the Vibration Perception Threshold (VPT). The aim of the study is to verify whether there are really acute effects on the VPT after a WBV training session in people with T2DM.

METHODS

Ninety people with T2DM (56 men and 34 women) were randomly allocated to two groups: the WBV group and the placebo group. The ninety subjects went through a VPT training test before receiving the assigned intervention, and they performed the VPT test using the Vibratron II device.

RESULTS

After one session of WBV, an increase of the VPT in the WBV group was found, with respect to the placebo group.

CONCLUSIONS

Vibration perception threshold is increased after a WBV training session in people with T2DM, compared to a placebo group.

Effects of whole-body vibration and high impact exercises on the bone metabolism and functional mobility in postmenopausal women

INTRODUCTION

This study determined the effects of whole-body vibration (WBV) and high-impact exercises on postmenopausal women.

MATERIALS AND METHODS

In this randomized controlled 6-month interventional trial, 58 eligible postmenopausal women were assigned to WBV training group, high-impact training group, or control group. Bone mineral density (BMD) of the lumbar spine and femur were measured by dual-energy X-ray absorptiometry. Additionally, the serum osteocalcin (OC) and C-terminal telopeptide of type I collagen levels were also measured. The functional mobility was assessed using the Timed Up and Go (TUG) test, and fall index was measured using static posturography. The health-related quality of life (HRQoL) and depressive symptoms were assessed using the Quality of Life Questionnaire of the European Foundation for Osteoporosis and Beck Depression Inventory, respectively.

RESULTS

The BMD at the femoral neck (p = 0.003) and L₂-L₄ (p = 0.005) regions increased significantly in the WBV group compared to the control group. However, in the high-impact exercise group there were no significant effects on the lumbar spine and femoral neck. The serum OC decreased significantly in the WBV group and increased significantly in both the high-impact exercise and control groups (p < 0.001). The TUG scores decreased significantly in both training groups compared to the control group (p < 0.05). Finally, in both exercise groups, HRQoL and depressive symptoms improved (p < 0.001).

CONCLUSIONS

Our data suggest that the WBV can prevent bone loss in postmenopausal women. These findings also indicate that WBV and high-impact training programs improve functional mobility, HRQoL and depressive symptoms in postmenopausal women.

Effects of Whole-Body Vibration on Functional Mobility, Balance, Gait Strength, and Quality of Life in Institutionalized Older People: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The aim of this study was to quantify the effect of whole-body vibration on balance, functional mobility, gait, functional performance, and quality of life in institutionalized older people. Eight databases were systematically reviewed, as recommended by the Cochrane Collaboration. This systematic review was designed to answer the acronym set by the participants, interventions, comparators, and outcomes (PICO)-model. Ten randomized controlled trials were included in the meta-analysis. The analysis of the mean differences (MDs) of the functional mobility assessed with Time Up and Go test was MD = -2.49 s (95% confidence interval, CI, [-4.37, -0.61]; I2 = 68%). In 279 participants from five studies, the overall MD = 0.49 (95% CI [-0.13, 1.11]; I2 = 23%) for gait, and MD = 0.96 (95% CI [-0.45, 2.37]; I2 = 85%) for balance, which represents the total Tinetti score, MD = 1.59 (95% CI [-0.52, 3.70]; I2 = 82%). In summary, whole-body vibration could have benefits on functional mobility in institutionalized older people.

Efficacy of Controlled Whole-Body Vibration Training on Improving Fall Risk Factors in Stroke Survivors: A Meta-analysis

Background. Controlled whole-body vibration (CWBV) training has been applied to people with stroke. However, it remains inconclusive if CWBV reduces fall risk in this population. Objective. To (1) assess the immediate and retention effects of CWBV training on fall risk factors in people at postacute and chronic stages of stroke and (2) examine if CWBV dosage is correlated with the effect size (ES) for 3 fall risk factors: body balance, functional mobility, and knee strength. Methods. Twelve randomized controlled trials were included. ES was calculated as the standardized mean difference, and meta-analyses were completed using a random-effects model. Results. CWBV training may lead to improved balance and mobility immediately after training (ES = 0.27, P = .03 for balance; ES = 0.34, P = .02 for mobility) but not at the 3-month follow-up test (ES = 0.02, P = .89 for balance; ES = 0.70, P = .11 for mobility). CWBV affects knee strength capacity with mild ES (ES = 0.08 and 0.11, respectively, for immediate and retention effect; P ≥ .68 for both). Metaregression indicated that the immediate ES is strongly correlated with training dosage for balance (r = 0.649; P = .029) and mobility (r = 0.785; P = .036). Conclusions. CWBV training may benefit balance and mobility immediately, but the training effect may not persist among people with stroke. Additionally, the CWBV dosage correlates with the ES for body balance and mobility. More high-quality studies are needed to determine the retention effects of CWBV training.

Comparação entre duas modalidades terapêuticas sobre o equilíbrio postural e medo de quedas em mulheres na pós-menopausa: um ensaio clínico randomizado e controlado

Resumo Objetivo: Comparar os efeitos do Pilates vs. vibração de corpo inteiro (VCI) e nenhuma intervenção sobre o equilíbrio postural e medo de quedas em mulheres na pós-menopausa. Métodos: Ensaio clínico Mono-cego, com 51 participantes randomizadas em três grupos (Pilates, VCI, ou Controle). Avaliações foram realizadas para o equilíbrio postural estático por intermédio da plataforma de força, equilíbrio postural dinâmico pelo teste Timed Up & Go e medo de quedas pela Falls Efficacy Scale-International (FES-I). Pilates e VCI foram administrados três vezes na semana, por seis meses. Resultados: Após a intervenção, nenhuma diferença (p> 0.05) foi observada para o equilíbrio postural estático, contudo, para a maior parte das variáveis, Pilates e VCI demonstraram um grande tamanho de efeito (d> 0.80) quando comparados ao grupo controle. Para o equilíbrio postural dinâmico, Pilates e VCI promoveram uma melhora significativa (p= 0.032) comparados ao grupo controle. Para o medo de quedas não houve diferença entre os grupos (p= 0.055) pós-intervenção. Conclusão: Tendo em vista a representatividade clínica evidenciada pelas medidas de tamanho de efeito, Pilates e VCI podem ser recomendados para melhora do equilíbrio postural estático e dinâmico em mulheres na pós-menopausa. Contudo, em relação ao medo de quedas, essas modalidades terapêuticas necessitam de melhor investigação.

Acute Effects of Whole-Body Vibration on the Postural Organization of Gait Initiation in Young Adults and Elderly: A Randomized Sham Intervention Study

Whole-body vibration (WBV) is a training method that exposes the entire body to mechanical oscillations while standing erect or seated on a vibrating platform. This method is nowadays commonly used by clinicians to improve specific motor outcomes in various sub-populations such as elderly and young healthy adults, either sedentary or well-trained. The present study investigated the effects of acute WBV application on the balance control mechanisms during gait initiation (GI) in young healthy adults and elderly. It was hypothesized that the balance control mechanisms at play during gait initiation may compensate each other in case one or several components are perturbed following acute WBV application, so that postural stability and/or motor performance can be maintained or even improved. It is further hypothesized that this capacity of adaptation is altered with aging. Main results showed that the effects of acute WBV application on the GI postural organization depended on the age of participants. Specifically, a positive effect was observed on dynamic stability in the young adults, while no effect was observed in the elderly. An increased stance leg stiffness was also observed in the young adults only. The positive effect of WBV on dynamic stability was ascribed to an increase in the mediolateral amplitude of "anticipatory postural adjustments" following WBV application, which did overcompensate the potentially destabilizing effect of the increased stance leg stiffness. In elderly, no such anticipatory (nor corrective) postural adaptation was required since acute WBV application did not elicit any change in the stance leg stiffness. These results suggest that WBV application may be effective in improving dynamic stability but at the condition that participants are able to develop adaptive changes in balance control mechanisms, as did the young adults. Globally, these findings are thus in agreement with the hypothesis that balance control mechanisms are interdependent within the postural system, i.e., they may compensate each other in case one component (here the leg stiffness) is perturbed.

Whole-body vibration impedes the deterioration of postural control in patients with multiple sclerosis

OBJECTIVE

The current study aimed to investigate if whole-body vibration (WBV) might attenuate the processing functional and neuromuscular degeneration of postural control in patients with MS.

DESIGN

Performance in postural control was assessed before and after 6 weeks of a control (CON) and a WBV intervention period.

SETTING

Laboratory at the University of Freiburg & home-based training PARTICIPANTS: Out of 29 interested participants, 15 subjects with severe MS fit inclusion criteria.

MAIN OUTCOME MEASURES

Centre of pressure displacement (COP), muscle activity and co-contraction indices of m. soleus (SOL), gastrocnemius medialis (GM), tibialis anterior (TA), biceps (BF) and rectus femoris (RF) as well as SOL H/M-ratios.

RESULTS

After CON, COP was significantly enhanced with reduced muscle activity in RF and diminished shank muscle co-contraction. After WBV, no changes were observed in COP and neuromuscular control. However, over time, TA activity was reduced, but with no changes in muscle activation of SOL, GM and BF or H/M-ratios.

CONCLUSIONS

After CON, MS patients experienced substantial deteriorations in postural control which have previously been associated with greater postural instability. No further disease-associated deteriorations were observed following the intervention. Thus, WBV might alleviate neurodegeneration of postural control in people with MS.

Targeted Subcutaneous Vibration With Single-Neuron Electrophysiology As a Novel Method for Understanding the Central Effects of Peripheral Vibrational Therapy in a Rodent Model

Very little is known about the effects of whole body vibration on the supraspinal central nervous system. Though much clinical outcome data and mechanistic data about peripheral neural and musculoskeletal mechanisms have been explored, the lack of central understanding is a barrier to evidence-based, best practice guidelines in the use of vibrational therapy. Disparate methods of administration render study to study comparisons difficult. To address this lack of uniformity, we present the use of targeted subcutaneous vibration combined with simultaneous in vivo electrophysiological recordings as a method of exploring the central effects of peripheral vibration therapy. We used implanted motors driven by both Grass stimulators and programmed microcontrollers to vary frequency and location of stimulation in an anesthetized in vivo rat model while simultaneously recording firing rate from gamma-aminobutyric acid (GABA) neurons in the ventral tegmental area. We show that peripheral vibration can alter GABA neuron firing rate in a location- and frequency-dependent manner. We include detailed schematics and code to aid others in the replication of this technique. This method allows for control of previous weaknesses in the literature including variability in body position, vibrational intensity, node and anti-node interactions with areas of differing mechanoreceptor densities, and prefrontal cortex influence.

Feasibility of whole body vibration during intensive chemotherapy in patients with hematological malignancies - a randomized controlled pilot study

BACKGROUND

Hospitalized cancer patients undergoing intensive or high-dose chemotherapy often experience a considerable decline in functional performance associated with the increased risk of adverse health events. Exercises, particularly resistance-based exercises that may counteract this decline are restricted by therapy-related side effects. Since whole body vibration (WBV) is known to efficiently stimulate the neuromuscular system without significantly raising blood pressure, we hypothesize that especially WBV is particularly feasible even during intensive or high-dose chemotherapy (primary endpoint) and thus induces beneficial functional adaptations.

METHODS

Twenty hospitalized patients with hematological malignancies scheduled for intensive or high-dose chemotherapy were randomly allocated to an intervention group (IG) undergoing WBV, or an active control group (CG) cycling. Feasibility was determined by comparing the IG's and CG's training compliance. Furthermore, to assess feasibility, WBV-induced changes in chemotherapy-related side effects, blood pressure, and heart rate immediately after exercising were documented. To assess patients' functional performance, we measured jump height (cm), the duration (sec) of performing the chair rising- (CRT) and timed-up-and-go test (TUG), maximum power output during jumping and CRT (watt/kg) as well as sway path (mm) during balance tasks.

RESULTS

Training compliance was similar between groups (IG: median 62%, range 39-77; CG: 67%, 58-100; p = 0.315). Moreover, we observed neither the IG's reported side effects worsening, nor any increase in blood pressure after WBV. IG's jump height (+ 2.3 cm, 95%CI 0.1-4.4, p = 0.028) and TUG performance (- 1.3 s, 95%CI -2.53 - -0.65, p = 0.027) improved significantly, while sway paths in semi-tandem stance were augmented after the intervention (eyes open: + 60 mm, 95%CI 2-236, p = 0.046; eyes closed: + 88 mm, 95%CI 49-214, p = 0.028). The CG's performances did not change over time. Maximum power output during CMJ and CRT and time during CRT did not change.

CONCLUSION

Our study is the first proving the feasibility of WBV during intensive/high-dose chemotherapy of hospitalized cancer patients. Additionally, WBV-induced neuromuscular adaptations resulted in functional benefits relevant to patients' autonomy. We believe that WBV can be implemented as an alternative training method during intensive chemotherapy, although the relative benefit compared to conventional resistance training requires more evaluation in future studies.

TRIAL REGISTRATION

German Register of Clinical Trials No.: DRKS00004338 , prospectively registered on 11/30/2012.

Transmissibility and waveform purity of whole-body vibrations in older adults

BACKGROUND

This study examined the transmission power and waveform purity of vertical (synchronous) whole-body vibrations upon its propagation in the human body among older adults.

METHODS

Forty community-dwelling older adults participated in the study (33 women; mean age: 60.3 (SD 5.7) years). Four vibration frequencies (25, 30, 35, 40Hz), two amplitudes (0.6 and 0.9mm), and six different postures were tested. Skin-mounted tri-axial accelerometers were placed at the medial malleolus, tibial tuberosity, greater trochanter, third lumbar vertebra, and forehead. The transmissibility of vibration was computed as the ratio of the root-mean-square-acceleration at different body sites to that of the platform. Signal purity was expressed by the percentage of total transmitted power within 1Hz of the nominal frequency delivered by the platform.

FINDINGS

Vibration frequency and amplitude were inversely associated with transmissibility in all anatomical landmarks except the medial malleolus. Amplification of signals was noted at the medial malleolus in most testing conditions. The effect of posture on whole-body vibration transmission depends on its frequency and amplitude. In general, toe-standing led to the lowest transmissibility. Single-leg standing had the highest vibration transmission to the hip, while erect standing had the highest transmissibility to the head. The purity of waveform of the vibration signals was well conserved as the vibrations were transmitted from the feet to the upper body.

INTERPRETATION

Whole-body vibration transmissibility was highly influenced by signal frequency, amplitude and posture. These parameters should be carefully considered when prescribing whole-body vibration to older adults.

Effect of whole-body vibration exercise in preventing falls and fractures: a systematic review and meta-analysis

OBJECTIVE

To investigate the effect of whole-body vibration exercise (WBV) on fracture risk in adults ≥50 years of age.

DESIGN

A systematic review and meta-analysis calculating relative risk ratios, fall rate ratio and absolute weighted mean difference using random effects models. Heterogeneity was estimated using I2 statistics, and the Cochrane Collaboration's risk of bias tool and the GRADE approach were used to evaluate quality of evidence and summarise conclusions.

DATA SOURCES

The databases PubMed, Embase and the Cochrane Central Register from inception to April 2016 and reference lists of retrieved publications.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials examining the effect of WBV on fracture risk in adults ≥50 years of age. The primary outcomes were fractures, fall rates and the proportion of participants who fell. Secondary outcomes were bone mineral density (BMD), bone microarchitecture, bone turnover markers and calcaneal broadband attenuation (BUA).

RESULTS

15 papers (14 trials) met the inclusion criteria. Only one study had fracture data reporting a non-significant fracture reduction (risk ratio (RR)=0.47, 95% CI 0.14 to 1.57, P=0.22) (moderate quality of evidence). Four studies (n=746) showed that WBV reduced the rate of falls with a rate ratio of 0.67 (95% CI 0.50 to 0.89, P=0.0006; I2=19%) (moderate quality of evidence). Furthermore, data from three studies (n=805) found a trend towards falls reduction (RR=0.76, 95% CI 0.48 to 1.20, P=0.24; I2=24%) (low quality of evidence). Finally, moderate to low quality of evidence showed no overall effect on BMD and only sparse data were available regarding microarchitecture parameters, bone turnover markers and BUA.

CONCLUSIONS

WBV reduces fall rate but seems to have no overall effect on BMD or microarchitecture. The impact of WBV on fractures requires further larger adequately powered studies. This meta-analysis suggests that WBV may prevent fractures by reducing falls.

PROSPERO REGISTRATION NUMBER

CRD42016036320; Pre-results.

Effects of whole-body vibration on balance and mobility in institutionalized older adults: a randomized controlled trial

OBJECTIVE

To investigate whether a comprehensive exercise program was effective in improving physical function among institutionalized older adults and whether adding whole-body vibration to the program conferred additional therapeutic benefits.

DESIGN

A single-blinded randomized controlled trial was conducted.

SETTING

This study was carried out in residential care units.

PARTICIPANTS

In total, 73 older adults (40 women, mean age: 82.3 ± 7.3 years) were enrolled into this study.

INTERVENTIONS

Participants were randomly allocated to one of the three groups: strength and balance program combined with whole-body vibration, strength and balance program without whole-body vibration, and social and recreational activities consisting of upper limb exercises only. All participants completed three training sessions per week for eight weeks.

OUTCOME MEASURES

Assessment of mobility, balance, lower limb strength, walking endurance, and self-perceived balance confidence were conducted at baseline and immediately after the eight-week intervention. Incidences of falls requiring medical attention were recorded for one year after the end of the training period.

RESULTS

A significant time × group interaction was found for lower limb strength (five-times-sit-to-stand test; P = 0.048), with the exercise-only group showing improvement (pretest: 35.8 ± 16.1 seconds; posttest: 29.0 ± 9.8 seconds), compared with a decline in strength among controls (pretest: 27.1 ± 10.4 seconds; posttest: 28.7 ± 12.3 seconds; P = 0.030). The exercise with whole-body vibration group had a significantly better outcome in balance confidence (pretest: 39.2 ± 29.0; posttest: 48.4 ± 30.6) than the exercise-only group (pretest: 35.9 ± 24.8; posttest: 38.2 ± 26.5; P = 0.033).

CONCLUSION

The exercise program was effective in improving lower limb strength among institutionalized older adults but adding whole-body vibration did not enhance its effect. Whole-body vibration may improve balance confidence without enhancing actual balance performance.

Effects of whole-body vibration therapy on perception thresholds of type 2 diabetic patients with peripheral neuropathy: a randomized controlled trial

[Purpose] The aim of this study was to investigate the effect of whole-body vibration training on perception thresholds in type 2 diabetic patients with peripheral neuropathy. [Subjects and Methods] Fifty-nine patients with diabetic neuropathy participated in the study. They were randomly divided into the experimental group (n=29) and the control group (n=30). The experimental group performed whole-body vibration training, whereas the control group performed only lower body training in the same posture without using whole-body vibrator for 6 weeks. Perception threshold variables were measured to examine the effect of training. [Results] Warm and cold pain thresholds did not show significant changes in both groups before and after training. Vibration perception threshold showed significant improvement in the experimental group. [Conclusion] Our findings suggest that whole-body vibration training can improve vibration perception threshold of type 2 diabetic patients with peripheral neuropathy.

Acute effects of whole body vibration on balance in persons with and without chronic ankle instability

Chronic ankle instability (CAI) is a common condition following ankle injury that is associated with compromised balance. Whole body vibration training (WBVT) programmes are linked with improved balance and function in athletic and non-athletic populations and may improve balance in CAI. Twelve healthy and seven CAI participants completed two randomly assigned interventions. Two Power Plate® platforms were attached back to back using a Theraband®. Participants stood on the active plate and inactive plate for WBVT and sham interventions, respectively. Each intervention included vibration of the active plate. Centre of pressure (COP) and the star excursion balance test (SEBT) were measured before and at 3, 15 and 30 min following the interventions. Significant improvements were found in the anterior direction of the SEBT following both interventions in CAI and varying patterns of improvement were observed for COP measurements in all participants. Therefore, WBVT does not appear to acutely improve balance in CAI.

Nonpharmacological interventions to treat physical frailty and sarcopenia in older patients: a systematic overview - the SENATOR Project ONTOP Series

Background

Physical frailty (PF) and sarcopenia are predictors of negative health outcomes such as falls, disability, hospitalization, and death. Some systematic reviews (SRs) have been published on different nonpharmacological treatments of frailty and sarcopenia using heterogeneous definitions of them.

Objective

To critically appraise the evidence from SRs of the primary studies on nonpharmacological interventions to treat PF (defined by Fried’s frailty phenotype) and sarcopenia (defined by the EWGSOP) in older patients.

Design

Overview of SRs and meta-analysis of comparative studies.

Data sources

PubMed, Cochrane Database of Systematic Reviews, EMBASE, and CINAHL were searched in October 2015.

Eligibility criteria for selecting studies

SRs that included at least one comparative study evaluating any nonpharmacological intervention to treat PF or sarcopenia in older patients in any health care setting. Any primary study described in these SRs with experimental design was included.

Data extraction and management

Two reviewers independently screened titles, abstracts, and full-texts of articles. Quality assessment was carried out by using criteria from the Cochrane Collaboration and the GRADE working group.

Results

Ten SRs with 5 primary studies satisfied the inclusion criteria. The most frequent interventions in the included studies were physical exercise (4) and nutritional supplementation (2). Muscle strength (MS; except for one study in a frail population) and physical performance (PP; except for another study in a frail population) improved with exercise and amino acid supplementation in frail and sarcopenic old adults. Falls and activities of daily living were assessed in two studies with opposite results. The overall quality of the evidence was low.

Conclusion

This overview of SRs highlights the importance of exercise interventions with or without nutritional supplementation to improve the PP in community-dwelling patients aged >65 years with PF and sarcopenia. MS improved with multidisciplinary treatment and exercise interventions in this population.

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

BACKGROUND

Dynapenia (age-associated loss of muscle strength not caused by neurologic or muscular diseases) and functional limitations (e.g. climbing stairs, chair rising) are important problems in elderly persons. Whole body vibration, used as an adjunct to classical resistance training or even as a stand-alone alternative, might help to reduce these problems. Its value might be highest in elderly persons with very low function, where whole body vibration can be used as a skilling up training until more conventional exercise types are possible. This systematic review and meta-analysis summarized the current evidence for whole-body vibration interventions on isometric maximum voluntary contraction, dynamic strength, power, rate of force development and functional strength in elderly categorised in different subgroups based on function levels.

METHODS

An extensive literature search was carried out in February 2014 and repeated in February 2015 at PubMed, Cochrane Central Register of Controlled Trials, Physiotherapy Evidence Database and CINAHL electronic databases. The International Clinical Trials Registry Platform from the World Health Organization was also searched. Randomized controlled trials measuring isometric maximum voluntary contraction, dynamic strength, power, rate of force development and functional strength in studies using WBV intervention in 65 years or older elderly individuals were included. The methodological quality of included studies was assessed using the Cochrane Collaboration's tool for assessing Risk of Bias. Studies were classified based on the level of physical capacitiy of the participants as "Go-Go", "Slow-Go" or "No-Go". Data were pooled using a random effects model.

RESULTS

Thirty-eigth articles of moderate methodological quality were included. The vibration modes for sinusoidal vertical whole-body vibration was between 25 and 40 Hz, the amplitude varied from 2 to 4 mm. Sinusoidal side-alternating -whole-body vibration revealed frequencies from 2.5 to 35 Hz with amplitudes ranging from 0.05 to 12 mm. Stochastic resonance whole-body vibration used frequencies between 3 and 6 Hz. Effect sizes in Go-Go were moderate after vertical sinusoidal Whole-body vibration compared to non-training control groups for isometric maximum voluntary contraction with effect size 0.48 (95 % CI 0.33 to 0.63) and for Dynamic Strength with effect size 0.47 (95 % CI 0.06 to 0.88). Side-alternating sinusoidal whole body vibration showed moderate effect sizes with 0.69 (95 % CI 0.32 to 1.06) for isometric maximum voluntary contraction, 0.50 (95 % CI 0.07 to 0.92) for power, 0.40 (95 % CI 0.16 to 0.64) for Rate of Force Development and 0.42 (95 % CI 0.13 to 0.71) for Functional Strength compared to non-exercise control. The analysis for Slow-Go showed for stochastic resonance whole-body vibration and Functional Strength an effect size of 0.97 (95 % CI -0.07 to 2.00) compared to non-exercise control in one study. No-Go showed for stochastic resonance whole-body vibration a moderate effect size with 0.50 (95 % CI -0.32 to 1.33) for Functional Strength compared to non-exercise control.

CONCLUSIONS

Whole-body vibration shows beneficial effects, mainly in the No-Go group elderly compared to non-training control and conventional strength training groups. The results suggest that WBV can be used as a skilling-up exercise in participants not able to perform standard exercises. Further studies with the various types of WBV in various sub-populations of elderly persons are needed to determine the most effective vibration modes.

TRIAL REGISTRATION

REGISTRATION NUMBER

CRD42013006489.