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Vários métodos de aquecimento têm sido empregados no campo do treinamento esportivo . O foam rolling (FR) é uma das técnicas mais populares. No entanto, permanece o esclarecimento so bre o s períodos ótimos de FR para melhorar ou manter o desempenho. Portanto, o objetivo do presente estudo foi explorar o efeito agudo de diferentes períodos do FR no desempenho do salto vertical contramov iment o (SV). Doze indivíduos recreacionalmente ativos (23,92 ± 4,08 anos, 7 0 ± 1 2 k g, 1 71 ± 8 cm ) fo ram voluntários para o estudo. Todos os participantes completaram todos os protocolos ex perim en tais co m entrada randomizada. Os participantes realizaram seis visitas separadas por 48 horas. A primeira sessão incluiu a coleta de dados antropométricos, familiarização com o FR e a técnica do SV. Em seguida, cin co protocolos experimentais foram executados em ordem aleatória: Protocolo controle (PC) - salto v ertical sem FR; P30 uma série de 30 segundos de FR antes do salto vertical; P60 - duas séries de 30 segun do s de FR; P90: três séries de 30 segundos de FR; P120 quatro séries de 30 segundos de FR. O FR foi implementado para quadríceps, isquiotibiais, glúteo e gastrocnêmio. Diferenças significativas no desempenho do salto vertical (p <0,012) foram observadas no P30 (47,4 ± 11,7 cm), P60 (48,9 ± 11,9 cm), P90 (48,5 ± 12,1cm), P120 (48,6 ± 11,3 cm) em relação à PC (46,8 ± 11,3 cm). Além disso , P 60, P9 0, P120 apresentaram maior desempenho de salto vertical em relação ao p rotocolo P3 0. Po rtanto , o s praticantes e treinadores devem considerar a utilização de 60-120 segundos de FR durante o aquecimento, com o objetivo de melhorar o desempenho do SV...(AU)
Several warm-up methods have been employed in the field of athletic training. Th e foam rolling (FR) is one of the most popular techniques; however, there is still a lack o f ev idence abo ut t he optimal FR periods to enhance strength performance. Therefore, the purpose of the present study was t o explore the acute effect of different periods of the FR on vertical countermovement jump. Twelve recreationally active individuals (23.92 ± 4.08 years, 70 ± 12 kg, 171 ± 8cm) volunteered for t he st udy . Treatment conditions were participants using a random assignment. Participan ts p erform ed six v isit s separated by 48 hours. The first session included the collection of anthropometric data and familiarizatio n with a foam roller and the vertical countermovement jump technique. Then, five experimental p rotocols were employed in a randomized order: control protocol (CP) - the vertical countermovement without FR; P30 - one set of 30 seconds of FR before the vertical jump; P60 - two sets of 30 seconds of FR; P90: three sets of 30 seconds of FR; P120 - four sets of 30 seconds of FR. The FR was implemented for quadriceps, hamstrings, gluteus, and gastrocnemius. Significant differences in vertical countermovement jump performance (p < 0.012) were observed under the P30 (47.4 ± 11.7 cm), P60 (48.9 ± 11.9 cm), P90 (48.5 ± 12.1), P120 (48.6 ± 11.3 cm) compared to CP (46.8 ± 11.3 cm). In addit io n, P60 , P 90 , P 12 0 sh o wed greater vertical jump performance compared to the P30 protocol. Therefore, t he p ractition ers sh o uld consider utilizing 60-120 seconds of FR during the warm-up with the goal of acutely improving the vertical countermovement jump performance...(AU)
Subject(s)
Humans , Male , Female , Physical Education and Training , Sports , Exercise , Muscle Strength , Track and Field , Volunteers , Efficiency , MethodsABSTRACT
Background: Lateral epicondylitis is an overuse injury of the tendon and involving the extensor muscle of forearm. Induced pain at the upper trapezius (UT) produces an increase in wrist extensor electromyographic activity (EMG) which could potentially lead to overuse injury, such as LE, at the elbow. Some studies found that there is a relation between scapular muscle muscle performance and lateral epicondylitis and loss of grip strength in lateral epicondylitis. There is a lack of literature of similar studies among computer operators. The most common wrong working posture in computer operator is excessive wrist extension it causes to the overuse injury like lateral epicondylitis. The context and purpose of the study: To find out the relationship between scapular muscle performance and grip strength in lateral epicondylitis among computer operators. Result: The correlation between scapular muscle performance and grip strength in LE among computer operators was done using Karl Person correlation coefficient. The result indicated that there is a significant relation between scapular muscle performance and grip strength in lateral epicondylitis. Conclusion: The study showed that there is an impairment of scapular muscle performance and grip strength in lateral epcondylitis among computer operators. Implication: Regular physical activity and proper ergonomics advice can improve quality of life among computer operators.
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OBJECTIVE: Kinesio tape (KT) is a visible adhesive restorative tape that has typically been utilized for injury prevention, recovery, and even performance improvement, but limited studies have assessed the effect of KT on muscle performance. The purpose of this study was to investigate the clinical impact of KT on muscle performance in healthy young soccer players. METHODS: Between 25 March and 21 April 2017, sixteen healthy soccer players with a mean age of 20±2.17 were enrolled in this prospective cohort study. All participants were selected from the college football team of Prince Sattam Bin Abdulaziz University. The muscle performance of the players was evaluated with an isokinetic dynamometer for the following three conditions: without tape, immediately after applying KT, and 8 hrs post-KT application while the tape remained on the same site. RESULTS: The differences in peak torque and total work among the three conditions were nonsignificant (p>0.05). Additionally, applying KT to the thigh muscles did not decrease or increase the performance of non injured healthy soccer players (p>0.05). CONCLUSION: KT does not lead to beneficial outcomes of muscle performance in healthy young soccer players.
Subject(s)
Humans , Male , Female , Adult , Young Adult , Soccer/physiology , Muscle, Skeletal/physiology , Athletic Performance/physiology , Athletic Tape , Prospective Studies , ElectromyographyABSTRACT
Abstract A specific drop jumps (DJs) protocol (using 100 jumps) has been largely used to induce muscle damage. However, it failed to show relevant drop in performance in well-trained individuals. Trained subjects may require a protocol with greater volume to induce decrease of muscle performance. The aim of this study was to assess muscle performance after two DJs damaging protocols with different volumes in well-trained individuals. Eighteen strength and/or power-trained males (4.92 ± 2.78 years of training experience) were randomly assigned into one of two groups: DJ100 (five sets of 20 DJs) or DJ140 (seven sets of 20 DJs), with 2-min of rest interval. DJs were performed from a 60-cm box. After landing, the volunteers performed a maximal vertical rebound jump. Muscle swelling increased significantly on both DJ100 and DJ140 (p < 0.001). Maximal isometric torque (MIT) decreased significantly on both DJ100 (p = 0.005) and DJ140 (p < 0.001). MIT showed no between-group difference on pre-assessment (p = 0.815). However, on post-assessment, MIT was significantly lower on DJ140 than DJ100 (p = 0.043). Countermovement jump (CMJ) decreased significantly on DJ140 (p = 0.001), but not on DJ100 (p = 0.802). There was no between-group difference on pre-assessment (p = 0.978). However, on post-assessment, CMJ was significantly lower on DJ140 than DJ100 (p = 0.038). DJ140 induced greater drop in isometric strength than DJ100 and only DJ140 significantly reduced jump performance. These results demonstrated that well-trained individuals require a great volume of DJs to reduce substantially muscle performance.
Resumo Um protocolo específico de Drop Jumps (DJs), com 100 saltos, tem sido amplamente utilizado para induzir o dano muscular. Entretanto, este protocolo tem falhado em mostrar uma queda relevante em indivíduos treinados. Objetivou-se avaliar o desempenho muscular após dois protocolos de DJs com diferentes volumes em indivíduos treinados. Dezoito homens treinados em força e/ou potência (4,92 ± 2,78 anos de treinamento) foram aleatoriamente designados em um dos dois grupos: DJ100 (cinco séries de 20 DJs) ou DJ140 (sete séries de 20 DJs), com 2 minutos entre as séries. Os DJs foram executados de uma caixa de 60 cm de altura. Após a aterrisagem, os voluntários executaram um salto vertical máximo. O inchaço muscular aumentou significativamente em ambos os grupos (p < 0,001). O torque isométrico máximo (TIM) reduziu significativamente tanto no DJ100 (p = 0,005) quanto no DJ140 (p < 0,001). O TIM não apresentou diferenças entre grupos no momento pré (p = 0,815). Entretanto, no momento pós, o TIM foi significativamente inferior no DJ140 em relação ao DJ100 (p = 0,043). O salto com contra movimento (SCM) reduziu significativamente no DJ140 (p = 0,001), mas não no DJ100 (p = 0,802). No momento pós, o SCM foi significativamente inferior no DJ140 em relação ao DJ100. O DJ140 induziu uma queda maior na força isométrica em relação do DJ100, e somente o DJ140 reduziu significativamente o desempenho no salto. Esses resultados demonstraram que indivíduos bem treinados requerem um grande volume DJs para reduzir substancialmente o desempenho muscular.
Subject(s)
Humans , Male , Adult , Physical Education and Training/methods , Muscle, Skeletal/injuries , Athletic Performance , Exercise TestABSTRACT
Objective：This study aimed to examine the effects of kilohertz-frequency alternating current (KFAC) on muscle performance and adverse event in patients with neuromuscular skeletal disorders.Methods：A literature search was conducted in PubMed, PEDro, CINAHL, and Cochrane CENTRAL until September 2017. The reviewer extracted data on subject characteristics, intervention, target muscle, and outcome measures in accordance with the Cochrane Handbook.Results：The literature search yielded 1295 studies, and 3 studies met the inclusion criteria (n＝32；mean age：45.3 years). KFAC stimulation combined with land-based exercise was likely more effective in increasing the quadriceps femoris muscle strength than exercise alone in patients after total knee arthroplasty (TKA). However, KFAC was not superior to low-frequency pulsed current in increasing pedaling work in patients with spinal cord injury. No severe adverse event relevant to KFAC was reported in all 3 studies. The quality of evidence was very low according to the GRADE approach.Conclusion：Additional KFAC may be more effective than exercise alone in improving the quadriceps femoris muscle strength in patients after TKA without any severe adverse event. Further studies to investigate the effects of KFAC are warranted to increase the confidence for the effects of KFAC treatment.
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AbstractIntroduction The isokinetic dynamometer enables accurate assessment of muscle function. In Brazil, few studies have assessed the isokinetic muscle performance in older adults making interpretation and comparison of results with other studies.Objectives To conduct a descriptive analysis of the performance of the muscle flexor and extensor muscles of the knee joint in elderly community and compare the performance between the age groups 65-74 years and 75 years or more.Methods This is a cross sectional observational study with a convenience sample of 229 elderly community. For the analysis of muscle performance was used isokinetic dynamometer (Biodex System 3 Pro™) in the angular velocities of 60 °/s and 180 °/s. The variables evaluated were peak torque, peak torque normalized by body weight, total work normalized by body mass, total work, average power and agonist/antagonist ratio. Descriptive analysis was used to characterize the sample. For comparison between age groups was used Student's t-test with α = 0.05.Results The elderly women with older age showed a statistically significant decrease in most of the variables (p < 0.05) except for the agonist and antagonist knee (p = 0.398).Conclusions The isokinetic was a sensitive tool to characterize the modifications caused by aging on muscle function. Elderly with results below the lower limits of the confidence intervals for all variables certainly has a decreased strength for the age group evaluated and must be addressed therapeutically. The results can be used as a benchmark in clinical practice and future research.
ResumoIntrodução O dinamômetro isocinético possibilita a avaliação acurada da função muscular. No Brasil, poucos estudos avaliaram o desempenho muscular isocinético em idosos, dificultando a interpretação e comparação dos resultados com outros estudos.Objetivos Realizar uma análise descritiva do desempenho muscular dos músculos flexores e extensores da articulação do joelho de idosas da comunidade e comparar o desempenho entre as faixas etárias de 65 a 74 anos e 75 anos ou mais.Métodos Trata-se de um estudo observacional transversal, com uma amostra de conveniência com 229 idosas da comunidade. Para a análise do desempenho muscular foi utilizado o dinamômetro isocinético (Biodex System 3 Pro®) nas velocidades angulares de 60 °/s e 180 °/s. As variáveis avaliadas foram o pico torque, pico de torque normalizado pela massa corporal, trabalho normalizado pela massa corporal, trabalho total, potência e a relação agonista/antagonista. Foi utilizada análise descritiva para caracterização da amostra. Para comparação entre as faixas etárias foi usado o teste-t de Student considerando α = 0,05.Resultados As idosas com idade mais avançada apresentaram um decréscimo estatisticamente significativo na maioria das variáveis analisadas (p < 0,05) com exceção da relação agonista e antagonista do joelho (p = 0,398).Conclusão O dinamômetro isocinético foi um instrumento sensível para caracterizar as modificações ocasionadas pelo envelhecimento na função muscular. Idosas com resultados abaixo dos limites inferiores dos intervalos de confiança para as variáveis pesquisadas apresentam uma força diminuída para a faixa etária avaliada e devem ser abordadas terapeuticamente. Os resultados podem ser utilizados como parâmetro de comparação na prática clínica e em futuras pesquisas.
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INTRODUÇÃO: Estudos demonstram que laserterapia pode melhorar o desempenho muscular e retardar o processo de fadiga muscular. Contudo poucos estudos referem-se à quantificação do desempenho por meio da biofotometria. O objetivo desse estudo é verificar os possíveis efeitos da fototerapia em relação a atividade e fadiga muscular. MÉTODOS: Foi realizado um ensaio clínico duplo-cego controlado randomizado com sete indivíduos adultos, atletas universitárias de voleibol feminino, saudáveis. A atividade muscular foi quantificada por meio da eletromiografia e os saltos pela biofotometria. A laserterapia (830nm, 30mW, 11J /ponto e 22 segundos) foi realizada no músculo tríceps sural a cada 3 cm² totalizando uma média de 20 pontos. Empregou-se o teste de Kolmogorov-Smirnov para análise da distribuição dos dados. RESULTADOS: Após o teste de normalidade o teste t-Student foi aplicado, considerando-se um nível de significância de 5% (p < 0,05). Não foi observada influência do laser em relação às variáveis estudadas. CONCLUSÃO: Apesar de muitos estudos demostrarem a correlação da fototerapia com a atividade muscular e fadiga, este estudo não apontou qualquer correlacão da laserterapia com a atividade e fadiga muscular.
INTRODUCTION: Studies show that laser therapy can increase muscle performance and delay the process of muscle fatigue. However, few studies have reported photogrammetry as a tool to analyze muscle performance. The objective of this study was to assess the possible effects of phototherapy in relation to activity and muscle fatigue. METHODS: We performed a crossover, randomized, double-blind, controlled trial with seven healthy female volleyball players. The muscle activities were quantified through electromyography, and jumps were quantified through photogrammetry Laser therapy (830 nm, 30 mW, 11 J per point and 22 seconds) was carried out on 3 cm² triceps surae muscle for an average of 20 points. The Kolmogorov-Smirnov test was used to analyze data distribution. RESULTS: After testing for normality, the Student t test was applied, considering a significance level of 5% (p <0.05). The laser had no effect with respect to the variables studied. Interestingly, a significant difference in motor recruitment values of the lateral gastrocnemius muscle was observed during plantarflexion movement. CONCLUSION: Although many studies have shown a correlation of phototherapy with muscle activity and fatigue, this study found no correlation of laser therapy with muscle activity or fatigue.
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Con el objetivo de analizar la composición corporal y el somatotipo en seleccionadas nacionales de futbol femenino, se han estudiado 28 mujeres, 19 seleccionadas de Colombia y 9 de Paraguay, de 16,2 +/- 0,66 años de edad, participantes en el Campeonato Sudamericano Sub 17 Chile 2008, clasificatorio para la primera Copa Mundial FIFA de la categoría, Nueva Zelanda 2008. Para la evaluación se siguió el protocolo establecido por la Sociedad Internacional para el Avance de la Cineantropometria ISAK. Se determinó el fraccionamiento del peso corporal total en cinco masas según Kerr. Para establecer el somatotipo se utilizó el modelo propuesto por Heath & Carter. Respecto a las masas corporales, el promedio de los kg y por ciento de MA, MM y MO fue de 18,56 kg-33,28 por ciento; 21,80 kg-39,31 por ciento; 6,20 kg-11,18 por ciento. La clasificación del somatotipo es de endomorfo-mesomorfo, en el cual hay una dominancia equilibrada de adiposidad y muscularidad sobre la linealidad relativa. Los SDD del SM indican que no existen diferencias significativas (p<0,05) entre los diferentes puestos de juego, y el SDI sugiere que el grupo total de evaluadas es homogéneo.
In order to analyze body composition and somatotype in women selected to participate in the national soccer teams, we studied 28 women, 19 selected from Columbia and 9 from Paraguay, with an average of 16.2 +/- 0.66 years of age, participating in the South American Championship Sub 17 - Chile 2008, a qualifying event for the FIFA World Cup first category, New Zealand 2008. The evaluation followed the protocol established by the International Society for the Advancement of Kinanthropometry - ISAK. We determined the classification of total body mass in five types according to Kerr. To establish the somatotype the model proposed by Heath & Carter was used. Regarding body mass, the average kg and percent of MA, MM and MO was 18.56 kg-33.28 percent; 21.80 kg-39.31 percent; 6.20 kg-11.18 percent. The classification of somatotype was endomorph-mesomorph, where there is an equal dominance of adiposity and muscularity on the relative linearity. The SDD of SM indicates no significant differences (p<0.05) exists among the different positions of the players, and the SDI suggests that the total group of evaluated players is homogeneous.
Subject(s)
Female , Body Composition , Muscle, Skeletal/anatomy & histology , Soccer , Somatotypes , Anthropometry , Muscle, Skeletal/physiology , Somatotypes/physiologyABSTRACT
O objetivo deste estudo foi avaliar a capacidade funcional e o desempenho da musculatura respiratória e periférica e relacioná-los com o estado nutricional e volume expiratório forçado no primeiro segundo (VEF1). MATERIAIS E MÉTODOS: Foram avaliados 12 pacientes com doença pulmonar obstrutiva crônica (DPOC) moderada a grave (70±7 anos, VEF1 de 52±17 por cento previsto, índice de massa corpórea (IMC) de 23±4kg/m²) e sete indivíduos saudáveis (69±8 anos, VEF1 de 127±12 por cento previsto, IMC de 27±3kg/m²). Todos realizaram análise da composição corporal, medida da força muscular respiratória (pressão inspiratória máxima, PImax, e pressão expiratória máxima, PEmax), teste de exercício cardiorrespiratório (TECR), avaliação da força de preensão palmar, pico de torque e trabalho total ou endurance do quadríceps femoral. RESULTADOS: Os pacientes com DPOC tiveram valores reduzidos do índice de massa magra corpórea (IMMC) (18±1 versus 21±1kg/m², p<0,05), da carga máxima atingida no TECR (60±20 versus 102±18watts, p<0,01), da PImax (58±19 versus 87±21cmH2O, p<0,05), da força de preensão palmar (38±6 versus 47±5kg, p<0,05), do pico de torque (103±21 versus 138±18Nm, p<0,05) e do trabalho total do quadríceps femoral (1570±395 versus 2333±568J, p<0,05) quando comparado com o grupo controle (teste t de Student não pareado). Não houve correlação entre VEF1 e as variáveis estudadas; o IMMC correlacionou-se com o trabalho total do quadríceps (Pearson, r=0,6290, p<0,05). CONCLUSÕES: Estes resultados indicam que os pacientes com DPOC apresentam fraqueza muscular inspiratória e periférica e menor capacidade funcional, quando comparados com o grupo saudável. Além disso, sugere que o grau de obstrução ao fluxo aéreo não é um bom preditor para quantificar as debilidades nutricionais e musculares dos pacientes com DPOC.
The aim of this study was to evaluate the functional capacity and the performance of respiratory and quadriceps muscles in patients with chronic obstructive pulmonary disease (COPD) and relate them to nutritional status and forced expiratory volume in the first second (FEV1). METHODS: Twelve patients with moderate COPD (70±7 years, FEV1 52±17 percent predicted, body mass index (BMI) 23±4kg/m²) and seven healthy volunteers (69±8 years, FEV1 127±12 percent predicted, BMI 27±3kg/m²) were evaluated. All of them underwent body composition analysis, measurement of respiratory muscle strength (maximum inspiratory pressure, MIP, and maximum expiratory pressure, MEP), cardiorespiratory exercise test (CET) and evaluation of palm grip strength, peak torque and total work or endurance of the quadriceps femoris. RESULTS: The patients with COPD had lower values for the free-fat mass (FFM) index (18±1 versus 21±1kg/m², p<0.05), maximum load attained in the CET (60±20 versus 102±18 watts, p<0.01), MIP (58±19 versus 87±21cmH2O, p<0.05), palm grip strength (38±6 versus 47±5kg, p<0.05), peak torque (103±21 versus 138±18Nm, p<0.05) and total work of the quadriceps femoris (1570±395 versus 2333±568J, p<0.05) when compared with the control group (independent Student's t test). There was no correlation between FEV1 and the variables studied, while the FFM correlated with the total work of the quadriceps (Pearson, r=0.6290, p<0.05). CONCLUSIONS: These results indicate that patients with COPD show weakness of the inspiratory and quadriceps muscles and lower functional capacity, when compared with a healthy group. Moreover, they suggest that the degree of airflow obstruction is not a good predictor for quantifying the nutritional and muscle impairments in patients with COPD.