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OBJECTIVE: To compare the effect of Whole-Body Vibration Exercise (WBVE) applied in push-up modified and half-squat positions, on handgrip strength (HS) and on the electromyography registry (EMGrms) of the flexor digitorum superficialis muscle (FDSM) of the dominant hand. METHODS: Nineteen healthy women (age 23.40 ± 4.03 years, bodyweight: 58.89 ± 9.87 kg), performed in a randomized order five different tests: (S1) Control; (S2) Push-up modified; (S3) Push-up placebo; (S4); Half-squatting; (S5) Half-squatting placebo. The HS and the EMGrms were assessed at baseline and immediately after the tests. ANOVA two-way design mixed test, with Tukey post hoc, was used to evaluate the HS, EMGrms and the ratio between EMGrms and HS, i.e., neural ratio (NR). Thus, the lower NR represents the greater neuromuscular modifications. The statistical significance level was set up at p < 0.05. RESULTS: WBVE on S2 increased HS compared to the stimulus applied to the S4 (p = 0.0001). The increase in HS was associated with a reduction in the EMGrms of the FDSM (p < 0.001) and a lower NR (p < 0.0001), i.e., greater neuromuscular modifications, in the S2 compared to the S4 after the tests. CONCLUSION: The distance of the stimulus and the positioning on the vibratory platform influence the maximum muscular strength due to neuromuscular modifications of hands in healthy women.
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The aim of this study was to investigate the effects of whole-body vibration (WBV) on vastus lateralis (VL) surface electromyographic (sEMG) amplitude during an isometric semi-squat exercise, using two different frequencies, and to verify the influence of additional filters on the analyzed sEMG signal's characteristics. Forty physically active women were randomly divided into two groups with 20 members each: one group performed an isometric semi-squat exercise at 30 Hz - while the other group performed the same exercise protocol at 50 Hz. The sEMG amplitude of the VL muscle was recorded during the exercise protocols in two conditions: with and without vibration. After removing vibration-induced artifacts using digital filters, sEMG amplitude of VL increased significantly (p < 0.05) without differences between the frequencies. The results of this study suggest that WBV at 30 Hz and 50 Hz increased the sEMG amplitude of the VL muscle during an isometric semi-squat exercise. Furthermore, applying sEMG filters during signal processing of WBV is necessary, because motion artifacts from the vibration frequencies may contribute to the contamination of the sEMG amplitude.
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BACKGROUND: Kinesio Taping (KT) is an elastic bandage that aims to improve neuromuscular performance, although there is no consensus as to its benefits. OBJECTIVE: To analyze the immediate and delayed effects of KT on the neuromuscular performance of the femoral quadriceps, on balance, and lower limb function in healthy subjects. METHOD: This is a randomized controlled trial. Thirty-six women with a mean age of 22.2±3.6 years and BMI of 22.5±2.3 Kg/m2 were divided into three groups: control, with ten minutes of rest (control, n=12), application of Kinesio Taping without tension (placebo, n=12) and with tension (KT, n=12) on the quadriceps. The primary outcome was isokinetic performance, while secondary outcomes were the single-hop test, one-footed static balance, and electromyographic activity. The evaluations were carried out in five stages: 1) before application of KT, 2) immediately after the application of KT, 3) after 24h, 4) after 48h, and 5) after 72h. Mixed ANOVA was used to determine differences between groups. RESULTS: There was no change in one-footed static balance, electromyographic activity of the VL in the lower limb function, nor in isokinetic performance between groups. CONCLUSION: KT promotes neither immediate nor delayed changes in neuromuscular performance of the femoral quadriceps in healthy women.
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Cinta Atlética , Extremidad Inferior , Fuerza Muscular/fisiología , Músculo Esquelético/fisiopatología , Músculo Cuádriceps/fisiología , Electromiografía , Humanos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
BACKGROUND: Whole body vibration has become a popular practice in training and rehabilitation centers. Although proposed as a useful adjunct to improve various aspects of musculoskeletal function, its real benefits and immediate physiological responses are still uncertain. OBJECTIVES: This study analyzed the immediate effects of whole-body vibration with two distinct frequencies on neuromuscular performance of the quadriceps femoris and in the postural control of healthy subjects. DESIGN: Randomized controlled trial. METHODS: Sixty physically active women were submitted to an evaluation of the oscillation of the center of pressure through baropodometry and isokinetic performance of quadriceps femoris muscle of the non-dominant limb, associated with the electromyographic amplitude assessment of vastus lateralis muscle. Subjects were randomly divided into three groups: control group - performed an exercise protocol with the vibrating platform off; 30 and 50 Hz groups - conducted the exercise protocol with the platform on, with a frequency of 30 and 50 Hz, respectively. RESULTS: There was a significant reduction in the time of peak torque in three evaluated groups (p < 0.001), with no differences between the groups (p = 0.586). There were no significant differences in pressure center oscillation, peak torque normalized for body weight, total work, and average power nor in the value of the root mean square in any of the groups. CONCLUSION: This study suggests that the exercise protocol on the vibrating platform does not change neuromuscular performance or the pressure center oscillation of healthy women. CLINICALTRIALS. GOV IDENTIFIER: NCT02416362.
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Fuerza Muscular/fisiología , Equilibrio Postural/fisiología , Músculo Cuádriceps/fisiología , Vibración/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Electromiografía , Femenino , Humanos , Persona de Mediana Edad , Modalidades de Fisioterapia , TorqueRESUMEN
ABSTRACT Background Kinesio Taping (KT) is an elastic bandage that aims to improve neuromuscular performance, although there is no consensus as to its benefits. Objective To analyze the immediate and delayed effects of KT on the neuromuscular performance of the femoral quadriceps, on balance, and lower limb function in healthy subjects. Method This is a randomized controlled trial. Thirty-six women with a mean age of 22.2±3.6 years and BMI of 22.5±2.3 Kg/m2 were divided into three groups: control, with ten minutes of rest (control, n=12), application of Kinesio Taping without tension (placebo, n=12) and with tension (KT, n=12) on the quadriceps. The primary outcome was isokinetic performance, while secondary outcomes were the single-hop test, one-footed static balance, and electromyographic activity. The evaluations were carried out in five stages: 1) before application of KT, 2) immediately after the application of KT, 3) after 24h, 4) after 48h, and 5) after 72h. Mixed ANOVA was used to determine differences between groups. Results There was no change in one-footed static balance, electromyographic activity of the VL in the lower limb function, nor in isokinetic performance between groups. Conclusion KT promotes neither immediate nor delayed changes in neuromuscular performance of the femoral quadriceps in healthy women.
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Humanos , Músculo Esquelético/fisiopatología , Extremidad Inferior , Músculo Cuádriceps/fisiología , Fuerza Muscular/fisiología , Cinta Atlética , Ensayos Clínicos Controlados Aleatorios como Asunto , ElectromiografíaRESUMEN
OBJECTIVES: Investigate the immediate effects of Kinesio Taping(®) on neuromuscular performance of femoral quadriceps and balance in individuals submitted to anterior cruciate ligament reconstruction. DESIGN: This is a randomized clinical trial. METHODS: Forty-seven male participants, between 12 and 17 weeks after anterior cruciate ligament reconstruction, underwent initial assessment consisting of postural balance analysis using baropodometry, followed by eccentric and concentric isokinetic assessment at 60°/s of knee extensors, concomitant to electromyographic signals captured from the vastus lateralis muscle. They were then randomly allocated to one of the following groups: control, placebo and Kinesio Taping(®). Kinesio Taping(®) group participants were submitted to Kinesio Taping(®) on the femoral quadriceps of the affected limb, while placebo group subjects used the same procedure without the tension proposed by the method. The control group remained at rest for 10min. All participants were reassessed following the same procedure as the initial evaluation. The following variables were analyzed: peak torque/body weight and muscle potential using dynamometry; amplitude of antero-posterior and latero-lateral displacement from the center of pressure using baropodometry; and amplitude of muscle activation (root mean square) applying surface electromyography. RESULTS: None of the variables analyzed showed significant intergroup or intragroup differences. CONCLUSIONS: Kinesio Taping(®) does not alter the neuromuscular performance of femoral quadriceps or balance of subjects submitted to anterior cruciate ligament reconstruction, for any of the variables analyzed.