Effects of wrist orthoses in reducing pain in individuals with carpal tunnel syndrome: a systematic review.

PURPOSE: To examine the effectiveness of wrist orthoses in reducing pain in individuals with carpal tunnel syndrome. MATERIALS AND METHODS: The searches were carried out in the CINAHL, Cochrane Library, EMBASE, Regional Portal of the Virtual Health Library, PubMed, Scopus, and Web of Science databases on 18 February 2021, and updated on 16 February 2023. Four independent evaluators performed the steps for inclusion of studies following the recommendations of the PRISMA and methods of the Cochrane Handbook for systematic review. RESULTS: Three randomized clinical trials, two quasi-randomized clinical trials and one cohort study met the inclusion criteria. The visual analogue scale and numeric analog scale were used as a tool to assess pain outcome. The treatment period ranged from 2 weeks to 3 months. The period of use varied between nighttime only, and nighttime plus daytime. Most orthoses promoted a statistically significant reduction in intensity pain at night, at rest or during activities. Only one study carried out follow-up after the end of treatment and showed that pain reduction was maintained up to 6 months after treatment. CONCLUSIONS: The findings suggest that the isolated use of orthoses were effective in reducing pain in individuals with carpal tunnel syndrome.

Orthoses are effective in reducing pain in individuals with carpal tunnel syndrome.Orthoses can be used nighttime or nighttime plus daytime according to the necessity.Prefabricated orthosis may represent lower cost and greater accessibility.Pain reduction can be maintained up to 6 months after the end of treatment.

Effects of photobiomodulation and a physical exercise program on the expression of inflammatory and cartilage degradation biomarkers and functional capacity in women with knee osteoarthritis: a randomized blinded study.

BACKGROUND: The knee osteoarthritis (OA) is a joint disease characterized by degradation of articular cartilage that leads to chronic inflammation. Exercise programs and photobiomodulation (PBM) are capable of modulating the inflammatory process of minimizing functional disability related to knee OA. However, their association on the concentration of biomarkers related to OA development has not been studied yet. The aim of the present study is to investigate the effects of PBM (via cluster) with a physical exercise program in functional capacity, serum inflammatory and cartilage degradation biomarkers in patients with knee OA. METHODS: Forty-two patients were randomly allocated in 3 groups: ESP: exercise + sham PBM; EAP: exercise + PBM and CG: control group. Six patients were excluded before finished the experimental period. The analyzed outcomes in baseline and 8-week were: the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) and the evaluation of serum biomarkers concentration (IL-1ß, IL-6, IL-8, IL-10 e TNF-α, and CTX-II). RESULTS: An increase in the functional capacity was observed in the WOMAC total score for both treated groups (p < 0.001) and ESP presents a lower value compared to CG (p < 0.05) the 8-week post-treatment. In addition, there was a significant increase in IL-10 concentration of EAP (p < 0.05) and higher value compared to CG (p < 0.001) the 8-week post-treatment. Moreover, an increase in IL-1ß concentration was observed for CG (p < 0.05). No other difference was observed comparing the other groups. CONCLUSION: Our data suggest that the physical exercise therapy could be a strategy for increasing functional capacity and in association with PBM for increasing IL-10 levels in OA knee individuals. TRIAL REGISTRATION: ReBEC (RBR-7t6nzr).

Effects of photobiomodulation and a physical exercise program on the expression of inflammatory and cartilage degradation biomarkers and functional capacity in women with knee osteoarthritis: a randomized blinded study

Abstract Background: The knee osteoarthritis (OA) is a joint disease characterized by degradation of articular cartilage that leads to chronic inflammation. Exercise programs and photobiomodulation (PBM) are capable of modulating the inflammatory process of minimizing functional disability related to knee OA. However, their association on the concentration of biomarkers related to OA development has not been studied yet. The aim of the present study is to investigate the effects of PBM (via cluster) with a physical exercise program in functional capacity, serum inflammatory and cartilage degradation biomarkers in patients with knee OA. Methods: Forty-two patients were randomly allocated in 3 groups: ESP: exercise + sham PBM; EAP: exercise + PBM and CG: control group. Six patients were excluded before finished the experimental period. The analyzed outcomes in baseline and 8-week were: the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) and the evaluation of serum biomarkers concentration (IL-1β, IL-6, IL-8, IL-10 e TNF-α, and CTX-II). Results: An increase in the functional capacity was observed in the WOMAC total score for both treated groups (p < 0.001) and ESP presents a lower value compared to CG (p < 0.05) the 8-week post-treatment. In addition, there was a significant increase in IL-10 concentration of EAP (p < 0.05) and higher value compared to CG (p < 0.001) the 8-week post-treatment. Moreover, an increase in IL-1β concentration was observed for CG (p < 0.05). No other difference was observed comparing the other groups. Conclusion: Our data suggest that the physical exercise therapy could be a strategy for increasing functional capacity and in association with PBM for increasing IL-10 levels in OA knee individuals. Trial registration: ReBEC (RBR-7t6nzr).

Acute Photobiomodulation Effects Through a Cluster Device on Skeletal Muscle Fatigue of Biceps Brachii in Young and Healthy Males: A Randomized Double-Blind Session.

Objective: The aim of this study was to investigate and compare the acute effects of red and infrared photobiomodulation (PBM) using a cluster device on biceps brachii muscle fatigue in young and healthy males. Background: Vigorous physical activity could lead to muscle fatigue, which compromises motor control and muscle strength and consequently impairs performance. The positive effects of PBM in reducing fatigue onset have been highlighted. However, the better wavelength with cluster devices is not yet established. Methods: A randomized double-blind session was used. Thirty-two young and healthy males were randomized into the control group (CG), red PBM group (RPG), and infrared PBM group (IPG). A PBM cluster device [7 visible diodes (630 nm), 7 infrared diodes (850 nm), 100 mW/diode, 2 W/cm2 power density, 91 J/cm2 energy density, 4 J per point, 28 J total energy, and 40 sec] was applied after muscle fatigue. Muscle fatigue was analyzed by surface electromyography (EMG) recorded from the long head of biceps brachii, blood lactate concentration, and evaluation of the rate of perceived exertion (RPE) using the Borg Scale. The fatigue protocol consisted of a maximum voluntary isotonic contraction of elbow flexion-extension with 75% of one-repetition maximum until exhaustion. The Borg Scale was applied before and at the end of the experiment to measure the RPE. The electromyography fatigue index (EMGFI) was calculated by windows of median frequency from EMG data. Results: EMGFI, blood lactate concentration, and RPE showed no intergroup statistical difference, except the EMGFI delta value that showed a difference between IPG and CG, with a greater value in the CG. However, intragroup comparisons showed that EMGFI decreased in the CG and RPE and lactate concentration increased significantly in all groups. Conclusions: There was no difference between red and infrared PBM in reduction of biceps brachii fatigue. However, the EMGFI delta value was greater in the IPG compared with the CG, suggesting that infrared can be more effective in reducing biceps brachii fatigue.

Photobiomodulation via a cluster device associated with a physical exercise program in the level of pain and muscle strength in middle-aged and older women with knee osteoarthritis: a randomized placebo-controlled trial.

Osteoarthritis (OA) is a chronic joint disease that leads to pain and functional incapacity. The aim of the study is to investigate the effects of the incorporation of photobiomodulation (PBM) (via cluster) into a physical exercise program on the level of pain, lower limb muscle strength, and physical capacity, in patients with knee OA. Sixty-two female volunteers with a diagnosis of knee OA were distributed in 4 groups: exercise associated with placebo PBM group, exercise associated with active PBM group, active PBM group, and placebo PBM group. Sixteen sessions of lower limb strength exercises and PBM via cluster (808 nm, 100 mW, 7 points each side, 56 J total) were performed. The level of pain, physical capacity, and lower limb muscle strength were evaluated with the use of the numeric pain rating scale (NPRS), 6-min walking test (6-MWT) and timed up and go (TUG), and maximal voluntary isometric torque (MVIT) before and after the interventions. Both groups presented a significant decrease in the level of pain when compared with the placebo-treated women. Furthermore, the 6-MWT showed that the trained groups (with or without PBM) demonstrated higher values in the distance walked comparing pre and post-treatment values. The same behavior was found for the MVIT load before and after intervention. TUG was higher for all the treated with exercise groups comparing the pre and post-treatment values. Physical exercise and PBM showed analgesic effects. However, PBM did not have any extra effect along with the effects of exercise in improving the distance walked, the TUG, and the muscle strength.Trial registration: RBR-7t6nzr.

Comparison of the effect of nocturnal use of commercial versus custom-made wrist orthoses, in addition to gliding exercises, in the function and symptoms of carpal tunnel syndrome: A pilot randomized trial.

BACKGROUND: Conservative treatment for carpal tunnel syndrome (CTS) often includes wrist orthosis. However, there is no consensus on whether commercial or custom-made wrist orthosis is better for the treatment. PURPOSE: To assess feasibility of a study comparing nocturnal use of commercial versus custom-made wrist orthosis in the treatment of mild/moderate CTS and estimate their potential effects on function and symptoms. STUDY DESIGN: Randomized clinical trial. METHODS: Twenty-four individuals with mild/moderate CTS were randomized to wear either a commercial orthosis (n = 12) or a custom-made orthosis (n = 12). Participants used the assigned orthosis at night for 45 days and performed gliding exercises at home/work. We collected data on access to eligible population and feasibility of protocol. Data on use of orthosis, performance of exercises, and symptoms were collected through a dairy filled by the participant. Outcomes were pain (using Numeric Pain Rating Scale), symptom severity and functional status (using Boston Questionnaire), pinch strength (by dynamometry), and electromyographic activity of forearm muscles (sampled during a reach-to-grasp task). Outcomes were measured before and after the intervention. RESULTS: There were no loses to follow-up in either intervention group. After treatment, we found increased tripod pinch strength and better symptoms and function in both orthosis groups, with better outcomes for the custom-made orthosis, although the differences were not statistically significant. CONCLUSIONS: The preliminary results showed a potential for better outcomes from the custom-made orthosis. We established that a larger study would be feasible and could be designed and conducted based on the estimates provided by this study. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (ReBEC) - registration number: RBR-74rqnz.

Quadriceps femoris performance after resistance training with and without photobiomodulation in elderly women: a randomized clinical trial.

The study assessed if quadriceps femoris muscle performance of older women can be improved by applying photobiomodulation therapy after a resistance training program. This study is a randomized, controlled trial with concealed allocation, intention-to-treat analysis, and blinded outcome evaluators. Forty-five healthy sedentary older women classified as active or insufficiently active were randomized to groups receiving 8 weeks of quadriceps femoris resistance training plus active group or placebo group, or a control group (no training or photobiomodulation). Surface electromyographic fatigue indexes of vastus medialis, rectus femoris, and vastus lateralis; one-maximum repetition (1-MR); and analysis of inflammatory biomarkers (IL-6, IL-8, and TNF-α cytokines, plus CK and LDH enzymes) were measured at baseline and twice in a 24 h-period after 8 weeks. No differences among the three groups were found in fatigue indexes for all three muscles, although in general, the active group presented improved fatigue indexes from baseline to 8-week outcome, while the other groups did not. Both training groups improved in 1-MR over the 8-week period. Inflammatory biomarkers were not different at long- or short-term among the three groups, except differences in groups for long-term IL-8 changes, differences in time for long-term LDH and short-term TNF-α changes, and interactions of time by group for short-term LDH changes. Quadriceps femoris performance of older women was not improved when photobiomodulation was associated to the proposed quadriceps femoris resistance training, when compared to training without photobiomodulation and a sedentary group.

Aplicação do MiniBESTest para avaliar o equilíbrio de pacientes obesos submetidos à cirurgia bariátrica / MiniBESTest application to assess the balance of obese patients undergoing bariatric surgery

Introdução: A obesidade pode ocasionar alterações morfológicas que comprometem o controle postural. A cirurgia bariátrica é considerada uma das opções de tratamento. Objetivo: Analisar, através do MiniBESTest, se a mudança na massa corporal influencia no equilíbrio postural de obesos submetidos à cirurgia bariátrica. Métodos: Neste estudo de coorte transversal com amostra por conveniência, 24 voluntários foram divididos em Grupo Obeso (GO; indivíduos com obesidade grau II e III); Grupo Sobrepeso (GS; indivíduos com sobrepeso) e Grupo Eutrófico (GE; indivíduos eutróficos). Esta pesquisa compreendeu 2 etapas. Na Etapa I, os voluntários foram submetidos à avaliação física seguida da avaliação do equilíbrio postural (MiniBESTest). Na Etapa II, as avaliações da Etapa I foram feitas no GO 30 dias após cirurgia bariátrica. As variáveis peso, idade, altura, relação cintura-quadril, índice de massa corporal (IMC) e pontuação do MiniBESTest foram comparadas entre grupos pela Análise de Variância seguido do teste de comparações múltiplas de Bonferroni. Resultados: O GO apresentou peso e IMC maiores na Etapa I comparado aos demais grupos, assim como relação cintura-quadril maior em comparação ao GE. Conclusão: Os resultados mostram que a perda de massa corporal um mês após a cirurgia bariátrica não influenciou o equilíbrio de obesos avaliado pelo MiniBESTest.

Introduction: Obesity can cause morphological alterations in the body that compromise postural control. Bariatric surgery is considered one treatment for obesity. Objective: To analyze through MiniBESTest the effects that change in the body mass could have on postural balance in obese submitted to bariatric surgery. Methods: In this cross-sectional cohort study with sample for convenience, 24 volunteers were divided into Obese Group (OG, individuals with grade II and III obesity); Overweight group (OG, overweight individuals) and Eutrophic Group (EG, eutrophic individuals). This research comprised two Stages. In Stage I, volunteers were submitted to physical evaluation followed by postural balance evaluation (MiniBESTest). In Step II, same evaluations done in Step I was repeated in OG 30 days after surgery. Mean values and standard deviation of weight, age, height, waist-to-hip ratio, body mass index and score of MiniBESTest were compared between groups by the Analysis of Variance followed by Bonferroni multiple comparisons. Results: Before surgery, OG showed greater values of weight and BMI compared to the other groups, and greater value of waist-to-hip ratio compared to EG. Conclusion: Results showed that the loss of body weight 30 days after surgery not influenced the postural balance of obese evaluated by MiniBESTest.

Balance and postural control in basketball players / Equilíbrio e controle postural em atletas de basquetebol

Abstract Introduction: Basketball is one of the most popular sports involving gestures and movements that require single-leg based support. Dorsiflexion range of motion (DROM), balance and postural control may influence the performance of this sport. Objective: To compare and correlate measures of balance, postural control and ankle DROM between amateur basketball athletes and non-athletes. Methods: Cross-sectional study, composed by 122 subjects allocated into one control group (CG = 61) and one basketball group (BG = 61). These groups were subdivided into two other groups by age: 12-14 years and 15-18 years. The participants were all tested for postural balance with the Star Excursion Balance Test (SEBT), postural control with the Step-down test and DROM with the Weight-bearing lunge test (WBLT). Between-groups differences were compared using repeated-measures multivariate analysis of variance. Normalized reaching distances were analyzed and correlated with the WBLT and Step-down test. Results: There was no difference in the scores of WBLT (P = .488) and Step-down test (P =. 916) between the groups. Scores for the anterior reach (P = .001) and total score of SEBT (P = .030) were higher in BG. The values for the posterolateral (P = .001) and posteromedial reach (P = .001) of SEBT were higher in BG at the age of 15-18. The correlation between the anterior reach of the SEBT and WBLT was significant in BG between 12-14 years (r = 0.578, P = .008), and in the CG between 15-18 years (r = 0.608, P=.001). Conclusion: The balance was better in the BG, although adolescents between 15-18 years have better balance control for the posteromedial and posterolateral reaches of the SEBT.

Resumo Introdução: O basquetebol é um dos esportes mais praticados na atualidade, o qual envolve gestos e movimentos que exigem apoio unipodal. Amplitude de movimento de dorsiflexão (ADMD), equilíbrio e controle postural podem influenciar o desempenho deste esporte. Objetivo: Comparar e correlacionar medidas de equilíbrio, controle postural e ADMD de tornozelo entre atletas de basquetebol amadores e não-atletas. Métodos: Trata-se de um estudo transversal, composto por 122 participantes. Estes foram distribuídos em grupo controle (GC = 61) e grupo basquete (GB = 61). Cada grupo foi subdivido em outros dois, de acordo com a idade: 12-14 e 15-18 anos. Todos foram avaliados para equilíbrio postural com Star Excursion Balance Test (SEBT), controle postural com Step-down teste e ADMD foi testada com Weight-bearing lunge test (WBLT). As diferenças entre os grupos foram comparadas pelo teste de medidas repetidas e análise de variância multivariada. Distâncias normalizadas dos alcances no SEBT foram analisadas e correlacionados com o WBLT e Step-down test. Resultados: Não houve diferença entre os grupos nos escores do WBLT (P = .488) e Step-down test (P = .916). A pontuação para alcance anterior (P = .001) e escore total de SEBT (P = .030) foram maiores no GB. Os valores para alcance posterolateral (P = .001) e posteromedial (P = .001) do SEBT foram maiores no GB de 15-18 anos. A correlação entre distância anterior do SEBT e WBLT foi significativa no GB de 12-14 anos (r = 0.578, P = .008) e no GC de 15-18 anos (r = 0.608, P = .001). Conclusão: O equilíbrio foi melhor no GB, embora adolescentes de 15-18 anos possuam melhor controle de equilíbrio para alcances posteromedial e posterolateral do SEBT.

Reliability of Electromagnetic Tracking of Scapular Orientation and Position in Healthy Sendentary Individuals / Confiabilidade da Avaliação da Orientação e Posição de Repouso da Escápula de Indivíduos Saudáveis e Sedentários com o Sistema Eletromagnético de Aquisição de Dados

Electromagnetic systems for motion analysis are claimed as a precise technique for tracking position and orientation of human body segments. To date, reliability electromagnetic tracking was described only for the dynamic assessment of the scapula motion, and no reliability studies on its resting posture or positioning were found. The aim of this study was to analyze intra- and inter-session reliabilities and absolute errors of the scapular orientation and position at habitual resting posture in healthy individuals. Twenty-two shoulder symptom-free individuals non participants in professional or recreational sports activities involving upper extremities were volunteers in this study. The equipment used was 3SPACE Liberty system (Polhemus Inc.). The same examiner collected the kinematic data from subjects in two different sessions, with an interval from seven to ten days. Intraclass Correlation Coefficient (ICC2,1 and ICC2, k) and Standard Error of Measurement (SEM) were calculated. Inter-session reliability ranged from good to excellent (ICC from 0.66 to 0.96) and intra-session reliability was excellent (ICC ≥ 0.97). SEM values found for linear distances were smaller than 0.02 cm and scapular rotations ranged from 0.72° to 5.48°. Results of this study demonstrated that electromagnetic data acquisition of scapula habitual posture is a reliable tool for defining scapular position and orientation in sedentary shoulder symptom-free individuals.

Sistemas eletromagnéticos para análise de movimento são conhecidos como precisos para registrar a posição e orientação dos segmentos do corpo humano. Até o momento, a confiabilidade do registro eletromagnético foi descrita apenas para a dinâmica da escápula, não sendo encontrados estudos de confiabilidade da posição de repouso ou postura da mesma. O objetivo deste estudo foi a análise da confiabilidade intra- e inter-sessão e erros absolutos do registro eletromagnético da posição e orientação da escápula na postura habitual de repouso de indivíduos saudáveis. Foram voluntários no estudo 22 indivíduos sem sintomas no complexo articular do ombro e não-praticantes amadores ou profissionais de esporte e atividade física envolvendo os membros superiores. O equipamento utilizado foi o sistema 3SPACE Liberty (Polhemus Inc.). Um mesmo avaliador coletou os dados cinemáticos em duas sessões diferentes com um intervalo de sete a dez dias. O Coeficiente de Correlação Intraclasse (ICC2,1 e ICC2,k) e o Erro Padrão de Medida (EPM) foram calculados. A confiabilidade inter-sessão variou entre boa a excelente (ICC de 0,66 a 0,96) e a confiabilidade intra-sessão foi sempre excelente (ICC ≥ 0,97). Os valores de EPM encontrados para as distâncias lineares foram menores que 0,02 cm e para as rotações da escápula relativa ao tórax variaram entre 0,72 º e 5,48 º. Os resultados deste estudo demonstraram que o registro eletromagnético da posição habitual de repouso da escápula é confiável para determinar a posição e a orientação da mesma em um população sedentária e sem sintomas no complexo articular do ombro.

Closed Kinetic Chain Upper Extremity Stability test (CKCUES test): a reliability study in persons with and without shoulder impingement syndrome.

BACKGROUND: The Close Kinetic Chain Upper Extremity Stability Test (CKCUES test) is a low cost shoulder functional test that could be considered as a complementary and objective clinical outcome for shoulder performance evaluation. However, its reliability was tested only in recreational athletes' males and there are no studies comparing scores between sedentary and active samples. The purpose was to examine inter and intrasession reliability of CKCUES Test for samples of sedentary male and female with (SIS), for samples of sedentary healthy male and female, and for male and female samples of healthy upper extremity sport specific recreational athletes. Other purpose was to compare scores within sedentary and within recreational athletes samples of same gender. METHODS: A sample of 108 subjects with and without SIS was recruited. Subjects were tested twice, seven days apart. Each subject performed four test repetitions, with 45 seconds of rest between them. The last three repetitions were averaged and used to statistical analysis. Intraclass Correlation Coefficient ICC2,1 was used to assess intrasession reliability of number of touches score and ICC2,3 was used to assess intersession reliability of number of touches, normalized score, and power score. Test scores within groups of same gender also were compared. Measurement error was determined by calculating the Standard Error of the Measurement (SEM) and Minimum detectable change (MDC) for all scores. RESULTS: The CKCUES Test showed excellent intersession reliability for scores in all samples. Results also showed excellent intrasession reliability of number of touches for all samples. Scores were greater in active compared to sedentary, with exception of power score. All scores were greater in active compared to sedentary and SIS males and females. SEM ranged from 1.45 to 2.76 touches (based on a 95% CI) and MDC ranged from 2.05 to 3.91(based on a 95% CI) in subjects with and without SIS. At least three touches are needed to be considered a real improvement on CKCUES Test scores. CONCLUSION: Results suggest CKCUES Test is a reliable tool to evaluate upper extremity functional performance for sedentary, for upper extremity sport specific recreational, and for sedentary males and females with SIS.

Effects of low-level laser therapy on biceps braquialis muscle fatigue in young women.

OBJECTIVE: This study aims to investigate the effects of low-level laser therapy (LLLT) on biceps brachi muscular fatigue in 20 young females. BACKGROUND DATA: Exhausting physical activity leads to muscular fatigue, which could decrease muscular strength, and may cause impairment in motor control and muscle pain. Several biochemical and biophysical resources have been studied in an attempt to accelerate the recovery of muscle fatigue. Among these, LLLT is emphasized. METHODS: Twenty subjects were randomized in one laser group and one placebo group in two sessions of a crossover design experimental procedure; the second session taking place within 7 days of the first. In the first session, subjects underwent a collection of surface electromyographic (SEMG) data of the biceps brachii muscle, followed by active or placebo LLLT at the same muscle, followed then by another EMG sample of biceps brachii. Blood samples were collected five times during the experimental procedure. Second session procedures were identical to the first, with exception of LLLT, which was the opposite of the first session. The fatigue protocol consisted of 60 sec of elbow flexion-extension movement performed with 75% of one maximum repetition. Blood lactate, EMG fatigue, and the number of elbow flexion-extension repetitions during the fatigue protocol were used to evaluate the effects of laser therapy (808 nm wavelength, 100 mW output power, power density of 35.7 W/cm(2), 70 sec each point and 7 J/point on eight points). RESULTS: No statistical differences were found for eletromyographic fatigue and blood lactate values between groups. Mean numbers of elbow flexion-extension repetitions were 22.6 ± 7.58 after placebo, and 25.1 ± 9.89 after active LLLT group, but these differences were not statistically significant (p=0.342). CONCLUSIONS: LLLT had limited effects on delaying muscle fatigue in a young female sample, although a tendency was observed in the active laser group toward showing lower electromyography fatigue of biceps brachii muscle. No intergroup differences were found in the number of muscle contractions and lactate concentration.

Effect of 808 nm low-level laser therapy in exercise-induced skeletal muscle fatigue in elderly women.

Aging process involves several structural changes in muscle tissue which lead to decrease in musculoskeletal function. One of the most common physiological modifications is the increase in fatigability in elderly people, which leads to inability to maintain strength and motor control. In this context, low-level laser therapy (LLLT) has demonstrated positive results in reducing fatigue during physical exercise. Thus, this study aimed to investigate the effects of LLLT on skeletal muscle fatigue in elderly women. Twenty-four subjects divided in two groups entered a crossover randomized triple-blinded placebo-controlled trial. Active LLLT (808 nm wavelength, 100 mW, energy 7 J) or an identical placebo LLLT was delivered on the rectus femoris muscle immediately before a fatigue protocol. Subjects performed a fatigue protocol which consisted of voluntary isotonic contractions of knee flexion-extension performed with a load corresponding to 75 % of 1-MR (Maximum Repetition) during 60 s. Surface electromyography (SEMG) signals were recorded from rectus femoris muscle of dominant lower limb to evaluate peripheral fatigability using median frequency analysis of SEMG signal. The number of repetitions of flexion-extension during fatigue protocol was also compared between groups. The values of median frequency were used to calculate the slope coefficient. The results showed no difference in the slope comparing placebo LLLT and active LLLT groups (p = 0.293). However, a significant difference was observed in the number of repetitions between groups, after active LLLT, subjects demonstrated significantly higher number of repetitions (p = 0.047). In this study, LLLT was efficient in increasing the mean number of repetitions during knee flexion-extension exercise, although results have not shown delay electromyographic fatigue.

Shoulder muscular activity during isometric three-point kneeling exercise on stable and unstable surfaces.

The purpose of this study was to determine if performing isometric 3-point kneeling exercises on a Swiss ball influenced the isometric force output and EMG activities of the shoulder muscles when compared with performing the same exercises on a stable base of support. Twenty healthy adults performed the isometric 3-point kneeling exercises with the hand placed either on a stable surface or on a Swiss ball. Surface EMG was recorded from the posterior deltoid, pectoralis major, biceps brachii, triceps brachii, upper trapezius, and serratus anterior muscles using surface differential electrodes. All EMG data were reported as percentages of the average root mean square (RMS) values obtained in maximum voluntary contractions for each muscle studied. The highest load value was obtained during exercise on a stable surface. A significant increase was observed in the activation of glenohumeral muscles during exercises on a Swiss ball. However, there were no differences in EMG activities of the scapulothoracic muscles. These results suggest that exercises performed on unstable surfaces may provide muscular activity levels similar to those performed on stable surfaces, without the need to apply greater external loads to the musculoskeletal system. Therefore, exercises on unstable surfaces may be useful during the process of tissue regeneration.

Reliability of electromyographic amplitude values of the upper limb muscles during closed kinetic chain exercises with stable and unstable surfaces.

The purpose of the present study was to evaluate the intra and interday reliability of surface electromyographic amplitude values of the scapular girdle muscles and upper limbs during 3 isometric closed kinetic chain exercises, involving upper limbs with the fixed distal segment extremity on stable base of support and on a Swiss ball (relatively unstable). Twenty healthy adults performed the exercises push-up, bench-press and wall-press with different effort levels (80% and 100% maximal load). Subjects performed three maximal voluntary contractions (MVC) in muscular testing position of each muscle to obtain a reference value for root mean square (RMS) normalization. Individuals were instructed to randomly perform three isometric contraction series, in which each exercise lasted 6 s with a 2-min resting-period between series and exercises. Intra and interday reliabilities were calculated through the intraclass correlation coefficient (ICC 2.1), standard error of the measurement (SEM). Results indicated an excellent intraday reliability of electromyographic amplitude values (ICC > or = 0.75). The interday reliability of normalized RMS values ranged between good and excellent (ICC 0.52-0.98). Finally, it is suggested that the reliability of normalized electromyographic amplitude values of the analyzed muscles present better values during exercises on a stable surface. However, load levels used during the exercises do not seem to have any influence on variability levels, possibly because the loads were quite similar.

Avaliação eletromiográfica de músculos da cintura escapular e braço durante a realização de exercícios com extremidade fixa e carga axial / Electromyographic assessment of scapular girdle and arm muscles during exercises with fixed boundary and axial load

O objetivo deste estudo foi comparar a atividade eletromiográfica de músculos da cintura escapular e braço entre os exercícios wall-press 90°, wall-press 45°, bench-press e push-up, realizados com a extremidade distal do segmento fixa sobre uma superfície estável e em esforço isométrico máximo. Participaram desta pesquisa 20 voluntários do sexo masculino, sedentários e sem história de trauma ou doenças na extremidade superior. A atividade elétrica da cabeça longa do músculo bíceps braquial, da porção anterior do músculo deltóide, da porção clavicular do músculo peitoral maior e do músculo serrátil anterior foi registrada por eletromiografia de superfície. O teste modelo estatístico ANOVA e o teste post-hoc de Tukey foram utilizados para determinar diferenças entre os valores de RMS de cada músculo e em cada exercício, normalizados pela contração isométrica voluntária máxima. Os resultados do presente estudo demonstram que o músculo bíceps braquial apresentou a menor atividade eletromiográfica em comparação com os demais músculos avaliados em todos os exercícios, enquanto a porção anterior do músculo deltóide e o serrátil anterior mostraram maior atividade eletromiográfica em relação aos demais músculos nos exercícios bench-press e push-up. Esses achados demonstram que não houve semelhança na atividade eletromiográfica dos músculos avaliados durante os exercícios, porém, houve coativação muscular, visto que os exercícios ativaram todos os músculos, mesmo que em diferentes níveis. Os exercícios estudados não são indicados para ativar o músculo bíceps braquial, mas os exercícios bench-press e push-up o são para ativar a porção anterior do músculo deltóide e o serrátil anterior; o wall-press 90° e o wall-press 45° são indicados para ativar a porção anterior do músculo trapézio.

The objective of this study was to compare the electromyography activity of scapular and arm muscles in the wall-press 90°, wall-press 45°, bench-press and push-up exercises, accomplished with the distal extremity of the segment on a stable surface and in maximum isometric effort. Twenty male sedentary (23±7 years), and without trauma history or diseases in the upper extremity volunteers participated in this research. The electric activity of the long head of the muscle biceps brachii, the anterior portion of the deltoid muscle, the clavicular portion of the pectoralis major and the serratus anterior muscle was registered by electromyography surface. The ANOVA and Tukey post hoc were used to determine differences between the RMS values of each muscle and in each exercise, normalized by the maximal voluntary isometric contractions. The results of the present study demonstrated that the biceps brachii muscle presented the smallest electromyographic activity in comparison to the other muscles in all exercises, while the anterior portion of the deltoid and the serratus anterior muscles presented larger electromyography activity in relation to the other muscles in the bench-press and push-up exercises. These findings demonstrate that there was not similarity in the electromyography activity of the evaluated muscles during the exercises; however, there was a muscular coactivation, since the exercises activated all muscles, even if at different levels. The studied exercises are not recommended for activation of the biceps brachii muscle; however, the bench-press and push-up exercises are recommended to activate the anterior portion of deltoid and serratus anterior muscles. Moreover, the wall-press 90° and the wall-press 45° are recommended for activation of the upper trapezius muscle.

Influência da posição do braço na relação EMG: força em músculos do braço / Influence of arm position EMG: force relatioship in arm muscles

A relação entre a amplitude do sinal eletromiográfico e a força muscular (EMC-força) tem sido tomada como medida indireta da força muscular. Este estudo, em 18 voluntárias e destras, visou avaliar a influência da posição do braço na relação EMG-força em músculos do braço em três tarefas...

The relationship between mioelectric signal amplitude and muscle strength (EMC-force) has been used as an indirect measure of muscle strength. The aim of this study, in 18 health, female, right-handed volunteers, was to assess the influence of arm position on the relationship EMG-force of arm position...