This study investigates (1) the presence of frequency transmission of oscillation from an external whole-body vibration (WBV) platform to the larynx; and (2) the factors that influence this frequency ...transmission.
Thirty participants (mean age=22.3years) with normal voice were exposed to four frequency-intensity levels of WBV (10 Hz-10%, 10 Hz-20%, 20 Hz-10%, 20 Hz-20%) and were instructed to produce the natural vowel /a/ three times during each WBV setting. The frequency was extracted from the middle 1-second of each electroglottographic (EGG) signal after passing through a Hann band filter with a range of 6–24 Hz. Linear mixed-effects models were applied to determine the factors that influenced the absolute deviation of the frequency transmission.
All participants exhibit an extracted EGG frequency that aligns with the external WBV frequency, deviating by − 0.6 to 1.2 Hz. The absolute deviation of WBV frequency transmission is consistent for both sexes across various WBV settings, except the 10 Hz-10% setting where men tend to exhibit significantly higher deviations (P = 0.018).
Oscillations at a specific frequency are transmitted from an external WBV platform to the larynx. This study proposes the use of a "spring" system to investigate the effect of WBV on the larynx, and recommends further research to explore the potential of WBV in managing voice disorders.
Continuous administration of low‐intensity whole‐body vibration (WBV) gradually diminishes bone mechanosensitivity over time, leading to a weakening of its osteogenic effect. We investigated whether ...discretizing WBV into bouts with short rest intervals was effective in enhancing osteoporotic bone repair. Ten‐week‐old female mice were ovariectomized and underwent drill‐hole defect surgery (Day 0) on the right tibial diaphysis at 11 weeks of age. The mice underwent one of three regimens starting from Day 1 for 5 days/week: continuous WBV at 45 Hz and 0.3 g for 7.5 min/day (cWBV); 3‐s bouts of WBV at 45 Hz, 0.3 g followed by 9‐s rest intervals, repeated for 30 min/day (repeated bouts of whole‐body vibration with short rest intervals rWBV); or a sham treatment. Both the cWBV and rWBV groups received a total of 20,250 vibration cycles per day. On either Day 7 or 14 posteuthanasia (n = 6/group/timepoint), the bone and angiogenic vasculature in the defect were computed tomography imaged using synchrotron light. By Day 14, the bone repair was most advanced in the rWBV group, showing a higher bone volume fraction and a more uniform mineral distribution compared with the sham group. The cWBV group exhibited an intermediate level of bone repair between the sham and rWBV groups. The rWBV group had a decrease in large‐sized angiogenic vessels, while the cWBV group showed an increase in such vessels. In conclusion, osteoporotic bone repair was enhanced by WBV bouts with short rest intervals, which may potentially be attributed to the improved mechanosensitivity of osteogenic cells and alterations in angiogenic vasculature.
•WBV can stimulate abdominal blood flow and therefore increase the distribution rate of a chemotherapy drug.•WBV have their own antitumor action, including by stimulating irisin and influences on ...mesenchymal stem cells.•In this way, the effectiveness of chemotherapy can be increased and the doses possibly reduced.•The hypothesis can be tested on experimental animals, and it is necessary to evaluate the adverse effects.
In oncological patients, whole body vibration (WBV) can be used to reduce cancer therapy-related morbidities, including in the case of intensive/high-dose chemotherapy. Based on the fact that WBV has the unique effect among physical exercises of intensifying blood circulation in the splanchnic territory, the medical hypothesis can be formulated according to which this type of training performed immediately after or ideally during intravenous chemotherapy would enhance the effectiveness of drug therapy due to the increase in the rate of distribution. This effect, which can benefit especially patients with abdominal tumors, may also allow the reduction of doses, thus reducing the probability of the occurrence of adverse reactions. Testing the hypothesis is possible on experimental animals, but for the organization of the research protocol, it must be taken into account that mechanical vibrations can destroy tumor cells by their own action, by influencing mesenchymal stem cells or by stimulating the secretion of irisin. Research on experimental animals is also necessary to discern whether mechanical vibrations do not affect the treatment of tumors with stem cells or do not decrease anti-tumor immunity.
This repeated-measures laboratory study characterized the relative impacts of vertical-axial dominant and multi-axial Whole-Body Vibration (WBV) exposures on postural stability. Eleven healthy ...participants were exposed to field-measured vibration profiles collected from on-road commercial (vertical-dominant WBV) and off-road mining vehicles (multi-axial WBV) for four hours on two different days. Before and after the exposure, postural stability was evaluated while participants performed sit-to-stand tasks followed by static standing tasks. Overall, the study results indicate that off-road, multi-axial WBV may compromise postural stability more so than on-road, vertical-dominant WBV. These findings may suggest that off-road vehicle operators are at a greater risk of fall-related injuries. Therefore, there is a critical need to develop more effective vibration control measures among off-road vehicle operators.
Aging is associated with functional decline and increased risk of contracting diseases. Osteoporosis (OP), a systemic disease, causes deterioration in bone microarchitecture and an increased ...propensity for fractures. Functional decline in the elderly is linked to decreased physical fitness, balance changes, increased risk of falls and impaired quality of life. Multicomponent Training (MCT) associated with Whole Body Vibration (WBV) brings functional benefits to the health of the elderly, as it is able to improve balance, muscle strength, functional capacity and reduce the risk of falls.
To verify the effect of MCT associated with WBV on functional capacity and quality of life in osteoporotic elderly women.
Case study approved by CEP/CCS/UFPE, position nº: 3.608.668. During the intervention, the volunteer underwent 3 reassessments (after the 8th, 16th and 24th session). To measure the functional capacity, the distances covered in meters in the 6-Minute Walk Test (6MWT) were considered and the evaluation of the quality of life was made through the results expressed in the WHOQOL-OLD questionnaire. The interventions lasted for 8 consecutive weeks, three times a week, totaling 24 sessions. MCT lasted 45 minutes, consisting of 3 stations: cardiorespiratory/aerobic resistance; strength/endurance and flexibility; body balance/stability, respectively. The WBV was performed on a side-to-side oscillating vibrating platform, with progressive frequency incremental increase up to 30 Hz and oscillation amplitude of 2 mm peak to peak, duration of 60 seconds and rest of 10 to 30 seconds. Statistical analysis was carried out descriptively with data summarization before and after the 8 interventions, calculating the percentage differences between the predicted values, the frequencies of cut-off points achieved and the percentage increase in gain or loss, being represented numerically or graphically.
Through the distance covered in the 6MWT, a variation from 521m to 564m in the last reassessment was verified. As for quality of life, the score ranged from 61.46% to 85.42% in the last reassessment.
The study showed significant effects on the functional capacity and quality of life of the evaluated elderly women. However, it is still not possible to state that the proposed protocol promotes greater benefits to the observed population in general.
Faced with the scarcity of protocols that prescribe MCT training associated with a vibrating platform in osteoporotic elderly women with risk of falls, the importance of proceeding with the proposed method was perceived in order to identify alternatives to guarantee functional capacity and quality of life in this population.
Purpose
Whole body vibration (WBV) training is purported to improve bone mineral density. Numerous randomized controlled trials present unclear data as to its clinical significance. This systematic ...literature review aims to collect the general consensus of data on the topic.
Data Sources
Systematic literature searches for randomized controlled trials between 2015‐2020 were performed in the databases of PubMed, PEDro Database, CINAHL Complete, Cochrane Library, EBSCO (Medline) between September 10 to October 1, 2020.
Methods and Data Extraction
19 randomized controlled trials (full text available, PEDro score > 6, human subjects, available in English, and conducted within the past 5 years) with a total of 695 subjects met methodological quality guidelines using the PEDro scale.
Results
A total of thirty‐nine (39) articles were screened, and nineteen (19) studies with a total population of n = 695 were included in the systematic review. With heterogeneity in modality and vibration intensity/frequency including dosing and prescriptions, no meta‐analysis was conducted. There were no significant differences found between WBV with and without resistive exercise (RE) vs no intervention in eight (8) of the randomized controlled trials (n= 223). There were statistically significant improvements reported in terms of improved BMD outcomes in WBV with or without RE vs no intervention in eleven (11) of the randomized controlled trials (n= 442), a positive trend towards improvement of BMD in one (1) of the randomized controlled trials (n= 30), and a mixed result of statistically significant improvement of BMD in lumbar spine and no effect towards BMD in femoral neck in one (1) of the randomized controlled trials (n=38). Our results revealed that WBV significantly elicits improvements in bone mineral density in majority of the studies.
Conclusion and Recommendations
The studies presented substantial evidence for recommending the use of WBV for improving bone mineral density. The use of WBV with and without RE significantly improves BMD when compared to no intervention. Studies to determine effective dosage of vibration to improve BMD are recommended in the field of WBV.
Objectives
To compare the effects of whole‐body vibration (WBV) and aerobic exercise on the hormonal profile and inflammatory status in women with premenstrual syndrome (PMS).
Methods
A prospective, ...randomized, pre–post‐test, single‐blind, controlled trial was conducted in 105 women diagnosed with PMS. They were randomized into three equal groups. All women received magnesium and vitamin B complex supplementation once daily. WBV training was added three times per week to the WBV group. The aerobic exercise group added aerobic exercise three times per week, while the control group received no additional intervention. The Premenstrual Syndrome Questionnaire (PMSQ) was used to assess PMS symptoms. Blood analysis was performed to measure hormone assays (estradiol, progesterone, prolactin, and cortisol) and high‐sensitivity C‐reactive protein at the start and after the end of the treatment program.
Results
There was no statistically significant difference between WBV and aerobic exercise according to PMSQ and high‐sensitivity C‐reactive protein (P = 0.99 and P = 0.98, respectively), but there was a statistically significant difference between both groups in cortisol, progesterone, prolactin, and estradiol (P = 0.001), with more favor given to the WBV group.
Conclusion
WBV and aerobic exercise have positive effects on women with PMS, with more favor given to WBV.
Synopsis
Whole‐body vibration and aerobic exercise have positive effects in women with premenstrual syndrome with more favor to whole‐body vibration.
The nonlinearity observed in the apparent mass of a seated human body exposed to vertical vibration demonstrates a decrease in resonance frequency as the vibration magnitude increases. However, there ...is a dearth of appropriate models that accurately capture this nonlinear biodynamic response. Furthermore, the impact of different properties of human body parts on this nonlinearity remains unexplored. This paper presents a model that effectively characterizes the nonlinearity in the apparent mass of a seated human body subjected to vertical vibration.
The proposed model incorporates the legs, thighs, pelvis, torso, head, and viscera as key components. Nonlinear springs are employed to simulate the dynamic interactions between the human body and the seat, as well as the connection between the viscera and the pelvis/torso. To validate the model, vertical in-line and fore-and-aft cross-axis apparent masses were measured at the seat pan for 11 subjects without backrest contact, using three different vibration magnitudes (0.4, 0.6, and 1.0 m/s2 r.m.s.).
A comprehensive global sensitivity analysis was conducted with the calibrated model to identify the factors that have the greatest influence on the biodynamic response. The results revealed that the stiffness of the soft tissues beneath the thighs, the mass of the thighs, and the mass of the torso were the three most influential parameters affecting the apparent mass. When considering the degree of nonlinearity in the apparent mass, the stiffness of the soft tissues beneath the thighs and the mass of the torso contributed the most.
The proposed model holds significant potential for studying the nonlinear biodynamic responses of vehicle drivers and passengers. It provides a valuable tool for gaining insights into the intricate dynamics of human body vibration and can contribute to the development of improved seating systems and enhanced ride comfort in vehicles.
Purpose
This study aimed to investigate the influence of whole‐body vibration (WBV) frequency, amplitude, and body posture on lower limb muscle activation among people with chronic stroke, and ...whether the EMG response to vibration stimulus differed between paretic and non‐paretic side. The relationship between muscle activation and WBV transmission was also examined.
Method
Thirty‐two participants with chronic stroke performed three different exercises on the WBV platform with different vibration conditions (frequency: 20 Hz, 30 Hz, 40 Hz; amplitude: 0.8 mm, 1.5 mm), or without vibration. Muscle activity in bilateral vastus medialis (VM), medial hamstrings (MH), tibialis anterior (TA), and medial gastrocnemius (MG) was measured by surface electromyography. Acceleration at the platform and bilateral hips and knees was measured by tri‐axial accelerometers.
Results
Significantly greater muscle activity was observed in the bilateral MG (P < 0.001), TA (P < 0.001), and MH (P < 0.001), but not VM, compared with the same exercises without WBV. WBV with higher amplitude or higher frequency led to greater augmentation of muscle activation (P < 0.05). Body posture significantly affected leg muscle activation (P < 0.001). WBV‐induced muscle activation was largely similar between paretic and non‐paretic sides, except the TA. Greater WBV‐induced leg muscle activation was associated with lower WBV transmissibility measured at the more proximal joints (P < 0.05).
Conclusion
Adding WBV to exercise significantly increased muscle activation in the MG, TA, and MH on both the paretic and non‐paretic sides of chronic stroke survivors, and the increase was dependent on the WBV amplitude, frequency, and body posture.
Pulsed electromagnetic fields (PEMFs) and whole‐body vibration (WBV) are proved to partially preserve bone mass/strength in hindlimb‐unloaded and ovariectomized animals. However, the potential ...age‐dependent skeletal response to either PEMF or WBV has not been fully investigated. Moreover, whether the coupled “mechano‐electro‐magnetic” signals can induce greater osteogenic potential than single stimulation remains unknown. Herein, 5‐month‐old or 20‐month‐old rats were assigned to the Control, PEMF, WBV, and PEMF + WBV groups. After 8‐week treatment, single PEMF/WBV enhanced bone mass, strength, and anabolism in 5‐month‐old rats, but not in 20‐month‐old rats. PEMF + WBV induced greater increase of bone quantity, quality, and anabolism than single PEMF/WBV in young adult rats. PEMF + WBV also inhibited bone loss in elderly rats by primarily improving osteoblast and osteocyte activity, but had no effects on bone resorption. PEMF + WBV upregulated the expression of various canonical Wnt ligands and downstream molecules (p‐GSK‐3β and β‐catenin), but had no impacts on noncanonical Wnt5a expression in aged skeleton, revealing the potential involvement of canonical Wnt signaling in bone anabolism of PEMF + WBV. This study not only reveals much weaker responsiveness of aged skeleton to single PEMF/WBV relative to young adult skeleton, but also presents a novel noninvasive approach based on combinatorial treatment with PEMF + WBV for improving bone health and preserving bone quantity/quality (especially for age‐related osteoporosis) with stronger anabolic effects.
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