Table 1.
Characteristics of included studies
| Author(s) (year), study design | Purpose | Method of LVT application | Outcome measures | Results and conclusions | PEDro score and shortcomings |
|---|---|---|---|---|---|
| Alghadir et al. (2017)9 Systematic review |
To investigate the effects of local vibration on muscle strength in healthy adults. 11 studies with a total of 346 participants were included. | The frequency and amplitude of the vibration signals were 8 to 300 Hz and 0.4 to 6 mm; and timing ranged from 6s to 30 minutes | Muscle strength (Peak isometric muscle strength) | Most of the studies reported significant improvements in muscle strength after the application of local vibration. There was considerable variation in the vibration training parameters and target muscle location | Average score of included studies was reported as 5.36/10 *SIGN Grade = high quality (++) |
| Benedetti et al. (2017)20 Randomized, controlled, single-blinded study |
To (a) investigate the clinical effectiveness of high-frequency LMV on quadriceps muscle in 30 patients with knee OA between the ages of 40–65, and (b) to determine the underlying mechanism of this potential effect | Vibration was applied at 150 Hz over the rectus femoris, vastus medialis, and vastus lateralis muscle bellies of the quadriceps by means of a cup-shaped transducer with a contact surface of 5 cm for 20 min | Clinical outcome was measured using the Western Ontario and McMaster Universities Osteoarthritis Index, Visual Analogue Scale, knee range of motion, Timed Up and Go test, and Stair climbing test; Changes in muscle activation and fatigue was studied with the use of surface EMG during a sustained isometric contraction |
The vibration group showed a significant change in Western Ontario and McMaster Universities Osteoarthritis Index score, Visual Analogue Scale score, Timed Up and Go test, Stair Climbing Test, and knee flexion; Surface EMG analysis suggested an increased involvement of type II muscle fibers in the group treated with vibration |
9/10 Blinding of therapists administering therapy was not specified |
| Bosco, Cardinale, Tsarpela (1999)15 Randomized controlled trial |
To evaluate the influence of vibration on the mechanical properties of arm Flexor in a group of 12 international level boxers | 5 repetitions lasting 1-min each at 30 Hz and 6 mm amplitude applied during arm flexion in isometric conditions with 1 min rest between repetitions | Mechanical Power and EMG analysis of arm flexors | Statistically significant enhancement of the average power and neuromuscular stimulation in the arm treated with vibrations | 5/10 Concealment of subject allocation, similarity of groups at baseline, and blinding of subjects, therapists, and assessors was not reported |
| Cochrane D. (Feb 2016)16 Randomized controlled trial |
To examine the acute effect of direct vibration has on bicep curl force-generating capacity. 11 healthy team and individual sport-trained males | Vibration was applied to the biceps brachii muscles at a frequency ranging between 0–170 Hz and amplitude of 0–0.12mm on a pulsed setting for a total of 10 minutes | Peak force, mean force, rate of force development, and electromyography (EMG) were assessed during the concentric phase before and immediately after direct vibration | Following direct vibration peak force increased compared to the control arm, but this change was not significant; There were no other significant changes in mean force, rate of force development, or EMG between vibration and control arms |
6/10 Concealment of subject allocation, and blinding of subjects, therapists, and assessors was not reported |
| Cochrane D. (June 2016)17 Randomized controlled trial |
To examine the acute effect of direct vibration on biceps brachii muscular power in 10 healthy male master field-hockey players | Vibration was applied to the biceps brachii muscles at a frequency ranging between 0–170 Hz and amplitude of 0–0.12mm on a pulsed setting for a total of 10 minutes | Mechanical peak power, mean concentric power and normalized electromyography (EMG) was assessed during the concentric phase of the biceps curl | Following vibration both peak power and mean concentric power increased compared to control; There was no significant difference in normalized EMG between vibration and control |
6/10 Concealment of subject allocation, and blinding of subjects, therapists, and assessors was not reported |
| Couto et al. (2013)25 Randomized, controlled, crossover study |
To verify the acute effects of the application of local vibration on upper limbs during resistance training on the number of maximum repetitions, metabolic and hormonal responses in 32 male volunteers | vibration was locally applied at 20-Hz and 12-mm amplitude via a latissimus pull-down cable machine | Maximum number of repetitions; Blood lactate, testosterone, cortisol, creatinine kinase, creatinine, urea |
No significant differences were observed in number of maximum repetitions between the control and vibration groups; Vibratory resistance training induced greater increases in testosterone and lactate concentrations; No significant changes were found in creatine kinase, creatinine or urea concentration. These data indicate that local vibration increases the metabolic and anabolic response to the resistance training, without changing the training volume |
5/10 Concealment of subject allocation, and blinding of subjects, therapists, and assessors was not reported; |
| Custer et al. (2017)19 Single-blind crossover study |
To examine the effects of a local-vibration intervention after a bout of exercise on balance, power, and self- reported pain in 19 healthy, moderately active subjects | Subjects received four 2-minute vibration interventions at 2-mm peak amplitude and frequency between 5 – 35 Hz | Static balance, dynamic balance, power via vertical jump test, self-reported pain | The local vibration intervention did not affect balance, power, or self-reported pain; There were no differences between outcome measures between the active and sham vibration conditions |
7/10 Concealment of subject allocation, and blinding of subjects and therapists was not reported |
| Goebel, Kleinoder, Yue, Gosh, Mester. (2015)4 Randomized controlled trial |
Biomechanical advantage of combining localized vibrations to hamstring muscles involved in a traditional resistance training routine was examined in 36 healthy male and female subjects with at least 2 years’ experience in resistance training | Local vibration was applied directly to hamstring muscles during exercise with a constant amplitude of 4 mm and a variable frequency between 18 – 38 Hz | Maximum isometric force of the hamstrings and maximum range of motion and muscle tension at maximum knee angle | The vibrational training group showed statistically significant improvements in maximum isometric force after the first week of training compared to 3 weeks for the traditional training regimen; The vibrational training group retained gain in performance for a longer time after the testing regimen than traditional training; The range of motion was improved, and muscle tension increase was less for the vibrational training group compared to the traditional training group |
6/10 Concealment of subject allocation, and blinding of subjects, therapists, and assessors was not reported |
| Iodice, Bellomo, Gialluca, Fano, Saggini (2010)3 Randomized controlled trial |
To evaluate the acute and long-term effects of local high-intensity vibration on muscle performance and blood hormone concentrations in 18 healthy young men | Vibration was delivered for 30 min at 300 Hz, 2mm amplitude over 3 sessions a week for a total of 4 weeks; Vibration was applied over the base of the vastus intermedius, rectus femoris, vastus lateralis, vastus medialis, gluteus maximus, biceps femoris, gastrocnemius, and tibialis anterior |
Counter-movement jumping (CMJ), maximal isometric voluntary contraction (MVC) test, and hormonal levels were measured before the procedure, immediately thereafter, and 1 h later | The HLV protocol significantly increased the serum level of growth hormone (GH, P \ 0.05) and creatine phosphokinase (CPK, P \ 0.05), and decreased the level of cortisol; There was a significant improvement in MVC; Overall, there were significant improvements in muscle performance after several weeks of vibration treatment, and some hormonal responses and minor performance improvements were detectable after a single session |
6/10 Concealment of subject allocation, and blinding of subjects, therapists, and assessors was not reported |
| Issurin and Tenenbaum (1999)5 Randomized controlled clinical trial |
To establish the acute and residual effects of vibratory stimulation in explosive strength exercises in 14 elite and 14 amateur athletes during bilateral biceps curl exercises | Vibration amplitude was transmitted indirectly via cables to the upper limb with an amplitude of 3 mm and frequency of 44 Hz | The acute and chronic /residual maximal and mean power of bilateral biceps curl exercises was measured | Exercise mode with vibratory stimulation resulted in a significant immediate effect for mean power and for maximal power | 6/10 Concealment of subject allocation, and blinding of subjects, therapists, and assessors was not reported |
| Kurt (2015)18 Randomized controlled trial |
To compare the effects of whole body vs. local vibration on lower body flexibility levels, and to assess whether vibration treatments were superior to static or dynamic stretching methods for lower body flexibility in 24 healthy well trained male combat athletes | Whole body or local vibration at a frequency of 30 Hz and a 4mm amplitude. Vibration was applied for 1 minute | Subjects performed the stand- and-reach test at the 15th second and the 2nd, 4th, 6th, 8th, and 15th minute following the intervention | Local vibration application showed statistically significant increased flexibility compared to other protocols. Subjects with high flexibility seem to benefit more from local vibration compared with other methods | 6/10 Concealment of subject allocation, and blinding of subjects, therapists, and assessors was not reported |
| Luo et al. (2008)24 Randomized cross-over study |
To determine whether vibration applied directly to a muscle-tendon could enhance neuromuscular output during and 1.5 and 10 min after a bout of ballistic knee extensions in 14 young male volunteers | Vibration at an amplitude of 1.2 mm and frequency of 65 Hz was applied with a portable vibrator strapped over the distal tendon of the quadriceps (time of vibration application not provided) | Knee joint angular velocity, moment, power, and rectus femoris and vastus lateralis electromyography were measured during the knee extension | Vibration did not induce significant changes in peak angular velocity, time to peak angular velocity, peak moment, time to peak moment, peak power, time to peak power, or average EMG of the rectus femoris and vastus lateralis; It was concluded that direct vibration, at the selected amplitude and frequency, does not enhance these neuromuscular variables in ballistic knee extensions during or immediately after training |
7/10 Concealment of subject allocation, and blinding of therapists and assessors was not reported |
| Luo et al. (2009)23 Randomized cross-over study |
To examine the influence of resistance load on the acute and acute residual effects of vibration training on the bicep tendon in 11 male subjects during a maximal-effort dynamic resistance exercise | Vibration was applied at an amplitude of 1.2 mm and frequency of 65 Hz over the biceps brachii tendon (time of vibration application not provided) | Concentric elbow joint angular velocity, moment, power, and bicep root mean square electromyogrphy (EMGrms) were measured during training and in the pre- and post-training tests | During training (acute effect) and at 5 minutes after training (acute residual effect), vibration did not induce a significant change in EMGrms, mean and peak angular velocities, moment, power, time to peak power, and initial power at 100 milliseconds after the start of the concentric phase for either resistance loads | 7/10 Concealment of subject allocation, and blinding therapists and assessors was not reported |
| Mischi et al. (2009)6 Cross-over study |
To evaluate the effects of activation and coactivation of biceps and triceps muscles during isometric exercises performed with and without superimposing vibration stimulation in 12 healthy volunteers. | A sinusoidal vibration was modulated at 28 Hz. The amplitude of the input sinusoidal waveform was set to 1.2V. An electromagnetic actuator produces a mechanical torque which is modulated in time by a sinusoidal function and then a mechanical transmission is used to transmit the generated force to the muscle | Root Mean Square of the recorded surface EMG signal | In general, a larger EMGRMS activity of the biceps and triceps brachii muscles was observed when vibration was applied | 4/10 Similarity of subjects at baseline, random allocation of subjects along with concealment of allocation was not stated; Additionally, blinding of subjects, therapists, and assessors was not reported |
| Moran, McNamara, Luo (2007)1 Randomized cross-over study | To examine the acute effects of direct vibration on neuromuscular performance in maximal-effort dynamic exercises in 14 young healthy adult males. To examine the acute residual effect of direct vibration training, both with and without a resistance exercise. Finally, to examine whether acute and acute residual effects of vibration training, if any, were placebo effects | Vibration was produced by a portable muscle-tendon vibrator that was strapped onto the skin over the biceps tendon. Vibration amplitude and frequency were set at 1.2mm and 65 Hz | Angular velocity, moment, power, and biceps root mean squared value of EMG and mean power frequency of EMG were determined for the concentric phase of muscle activation | Direct vibration of 65 Hz and an amplitude of 1.2mm applied to the biceps brachii muscle tendon does not enhance neuromuscular performance in maximal-effort contractions during or immediately after training | 7/10 Concealment of subject allocation, and blinding of therapists and assessors was not reported; Additionally, it is unclear if outcome measures were obtained from at least 85% of subjects initially allocated. |
| Pamukoff, Ryan, Blackburn (2014)2 Single group, cross-over study |
Compared the acute effects of 30 Hz vs. 60 Hz LMV exposure applied to the right quadriceps muscle in 20 healthy volunteers on strength, rate of torque development, and EMG amplitude. Secondarily, to determine the duration of the observed effects following LMV exposure | A custom-built LMV device was secured over the quadriceps tendon. Subjects were placed in an isometric squat and LMV was applied as 6×1min treatment at a frequency of 30 Hz (amplitude of 1.2mm) or 60 Hz (amplitude of 0.4mm) | Isometric knee extensor peak torque (PT), rate of torque development (RTD), and electromyography (EMG) of the quadriceps | Results suggest that 30 Hz LMV treatment acutely enhances EMG activity in the quadriceps muscles for at least 5 minutes, and may increase PT in healthy individuals. LMV had no effect on RTD | 6/10 Similarity of subjects at baseline, along with concealment of random allocation was not stated; Additionally, blinding of therapists and assessors was not reported |
| Peer, Barkley, Knapp (2009)7 Controlled clinical trial |
To determine whether segmental biomechanical muscle stimulation (BMS) muscle therapy increases range of motion and reduces perceived stiffness in physically 10 active individuals with acute and subacute ankle sprains or hamstring strains | Three BMS placements were used for 2 minutes each at 20 Hz for the ankle. Four BMS placements were used for 2 minutes each at 20 Hz. Amplitude was not provided although the authors mentioned that the Swisswing device used in the study was capable of 1–6mm amplitudes independent of frequency and load | Ankle dorsiflexion/plantar flexion/inversion/eversion, hamstring flexibility, and subjective ratings of stiffness were measured | Significant increase in ankle dorsiflexion and eversion, and hamstring flexibility, and significantly decreased perceived ankle and hamstring stiffness following segmental BMS at 20 Hz | 5/10 Random allocation of subjects along with concealment of subject allocation was not stated; Additionally, blinding of subjects, therapists, and assessors was not reported |
| Pietrangelo et al. (2009)8 Controlled clinical trial |
To determine whether a training program of passive muscle stimulation through local mechanical vibrations at high frequency applied to the lower limbs induced an increase in muscle mass and strength in 9 elderly subjects showing signs of sarcopenia | Local vibratory stimulation was applied on the skin of the distal part of the quadriceps. The duration of each application was 15 min and the frequency was 300 Hz (amplitude not provided) | Knee extensor isometric strength, thigh circumference, as well as needle biopsies of the vastus lateralis, cellular features and gene expression profiles were analyzed | Treated muscles displayed enhanced maximal isometric strength and increased content of fast MyHC-2X myosin. Single muscle fiber analysis did not show any change in cross-sectional area or specific tension. Changes in gene expression after 12 weeks of local vibration training in pathways related to energy metabolism, sarcomeric protein balance and oxidative stress response | 4/10 Similarity of subjects at baseline, random allocation of subjects along with concealment of allocation was not stated; Additionally, blinding of subjects, therapists, and assessors was not reported |
| Souron R, Besson T, et al. (2017)21 Randomized controlled trial |
To evaluate the effects of a 4-week local vibration training (LVT) program on the function of the knee extensors and corticospinal properties in 17 healthy young and old subjects | Vibration device set to 100 Hz and 1 mm amplitude and was strapped directly on the right rectus femoris muscle; Subjects received 3, 1-hour sessions over 4 weeks for a total of 12 sessions |
Jump performance, maximal voluntary force (MVC) and electromyographic (EMG) activity on vastus lateralis and rectus femoris muscles were assessed; Single pulse Transcranial Magnetic Stimulation (TMS) allowed evaluation of cortical voluntary activation (VATMS), motor evoked potential (MEP) area and silent period (SP) duration |
LVT seems as effective in young as in old subjects to improve maximal functional capacities through neural modulations and may be used as an efficient alternative training method to improve muscular performance in both healthy young and old subjects | 5/10 Random allocation of subjects along with concealment of subject allocation was not stated; Additionally, blinding of subjects, therapists, and assessors was not reported |
| Souron R, Farabet A, et al. (2017)22 Controlled clinical trial |
To evaluate the effects of an 8-week local vibration training (LVT) program on functional and corticospinal properties of dorsiflexor muscles in 44 male and female subjects | The vibration group performed 24, 1-hour sessions (3 sessions/week) at 100-Hz and 1mm amplitude applied to the right tibialis anterior | Maximal voluntary contraction (MVC) torque; Transcranial magnetic stimulation (TMS) was used to evaluate cortical voluntary activation (VATMS); Motor evoked potential (MEP); Cortical silent period (CSP) and input-output curve parameters |
Despite no changes in excitability or inhibition, local vibration seems to be a promising method to improve strength through an increase of maximal voluntary activation, i.e. neural adaptations | 5/10 Randomization and concealment of subject allocation, and blinding of subjects, therapists, and assessors was not reported |
| Tankisheva et al. (2015)14 Randomized controlled trial |
To investigate the effect of 6 months’ local vibration training on bone mineral density (BMD), muscle strength, muscle mass, and physical performance in 35 postmenopausal women (66–88 years) | 6-months of local vibration treatment with frequency between 30 – 45 Hz and acceleration between 1.71 – 3.58g; The vibration was applied for 30 minutes on the midthigh and around the hip in supine-lying position once per day, 5 days / week |
The primary outcome variables were the isometric and dynamic quadriceps muscle strength and the BMD of the hip; Muscle mass of the quadriceps and physical performance was also assessed via the Modified Physical Performance Test and Shuttle Walk Test |
A net benefit of 13.84% in isometric muscle strength at 60-degree knee angle in favor of the vibration group compared with controls; No changes in BMD, muscle mass, or physical performance were found in both groups; Overall, 6 months of local vibration training improved some aspects of muscle strength but had no effect on BMD, muscle mass, and physical performance in post-menopausal women |
8/10 Blinding of subjects and therapists who delivered therapy was not reported |