Comparação do desempenho funcional e parâmetros cinemáticos da marcha em idosos com fragilidade e saudáveis / Comparison of functional performance and kinematic gait parameters in frail and healthy elderly people

Objetivo: Comparar o desempenho funcional e as alterações cinemáticas da marcha em idosos saudáveis e em idosos com manifestações da síndrome da fragilidade, viventes na comunidade. Métodos: Estudo transversal do tipo caso-controle. Participaram do estudo 15 idosos, viventes na comunidade, separados em dois grupos, de acordo com a presença de manifestações de fragilidade: (n = 10) e controle (n = 5). Foram coletados dados sobre desempenho funcional, capacidade aeróbia, presença da síndrome da fragilidade e avaliação cinemática da marcha. Foram utilizados testes como: TC400m, dinamometria e SPPB. Para a análise de dados, foi utilizado o pacote estastístico PASW 18.0 (SPSS inc). Resultados: O tempo no teste de caminhada de 400m foi 11 segundos maior no grupo com sinais de fragilidade (p = 0,03), e a força de preensão palmar foi 25,8% maior no grupo sem fragilidade (p = 0,01). Conclusão: Concluimos que idosos frágeis possuem declínio no desempenho funcional em testes que avaliam a resistência aeróbia e a força muscular.

Objective: To compare functional performance and kinematic gait abnormalities in healthy elderly people and in elderly people with manifestations of the frailty syndrome, living in the community. Methods: A cross-sectional case-control study. Fifteen elderly people, living in the community, participated in the study. They were separated into two groups, according to the presence of manifestations of frailty (n = 10) and control (n = 5). Data on functional performance, aerobic capacity, presence of frailty syndrome, and kinematic gait assessment were collected. Tests, such as: TC400m, dynamometry, and SPPB were used. For data analysis, the statistical package PASW 18.0 (SPSS inc) was used. Results: The time in the 400m walk test was 11 seconds higher in the group with signs of frailty (p = 0.03), and handgrip strength was 25.8% higher in the group without frailty (p = 0.01). Conclusion: We conclude that frail elderly people have a decline in functional performance in tests that assess aerobic resistance and muscle strength.

Effects of automatic mechanical peripheral stimulation on gait biomechanics in older adults with Parkinson's disease: a randomized crossover clinical trial.

BACKGROUND: Automated mechanical peripheral stimulation (AMPS) is a rehabilitation technique suggested to correct gait abnormalities on Parkinson's disease. Although previous studies have suggested increments in functional performance and gait speed after AMPS intervention, little is known about its effect on gait biomechanics. OBJECTIVE: To analyze the effect of an AMPS session on functional performance and gait biomechanics in subjects with Parkinson's disease. METHODS: Twenty-eight subjects aged 67±3 years old participated in this study. Kinematics and muscle activation were recorded during walking at a preferred gait speed before and after AMPS and sham interventions. Footswitches sensors were used to record the kinematic parameters. Electromyographic (EMG) signals of tibialis anterior (TA) and gastrocnemius lateralis (GL) were recorded. Timed up and go (TUG) test and Short Physical Performance Battery (SPPB) were performed to assess functional performance. RESULTS: GL activation increased after AMPS intervention before and after heel strike (p = 0.04; p < 0.01) and before and after toe-off (p = 0.013; p = 0.038). Also, after AMPS intervention, TA activation increased after heel strike (p = 0.007); and after sham intervention, TA activation reduced before and after heel strike (p = 0.038; and p = 0.007) and before toe-off (p = 0.013). The time of TUG test was shorter after AMPS intervention (p = 0.015). CONCLUSION: AMPS intervention changed the EMG activation of ankle muscles during walking and functional performance. However, AMPS intervention did not change gait kinematics.

Associação da função do assoalho pélvico e mobilidade em idosas / Association of Pelvic Floor Function And Mobility In Elderly Women

Introdução: O envelhecimento populacional cresce a cada ano e, consequentemente, surgem adaptações fisiológicas do organismo, tais como: diminuição da velocidade da marcha, da estabilidade e da adaptação postural, além da perda da integralidade muscular; podendo levar a várias alterações, dentre elas: disfunções do assoalho pélvico e prejuízo na mobilidade. Objetivo: associar a função do assoalho pélvico à mobilidade em idosas. Materiais e métodos: trata-se de um estudo transversal, desenvolvido com mulheres acima de 60 anos, residentes na cidade de Bauru/SP. O estudo foi aprovado pelo Comitê de Ética em Pesquisa (parecer nº4.040.883), e todas as voluntárias, que assinaram o Termo de Consentimento Livre e Esclarecido, responderam aos questionários para caracterização sociodemográfica e verificação das queixas de disfunções do assoalho pélvico. A avaliação da mobilidade foi realizada pela marcha, por meio de uma passarela de 14 metros e da análise dos parâmetros cinemáticos da marcha pelo módulo de aquisição de sinais biológicos, com um acelerômetro triaxial posicionado sobre o maléolo lateral e uma bateria de avaliação Short Physical Performance Battery (SPPB). Resultados: No total, foram avaliadas 13 mulheres (7 no grupo com disfunção do assoalho pélvico e 6 no grupo controle), com média de idade de 64 ± 6,3 anos. As disfunções do assoalho pélvico relatadas foram: 54% de incontinência urinária, 8% de prolapsos de órgãos pélvicos, 15% de incontinência fecal e 8% de disfunção sexual. Nos resultados do SPPB, 92% das voluntárias apresentaram boa capacidade; 8%, baixa capacidade. Na avaliação da marcha, não foram encontradas diferenças estatísticas entre os grupos (p=0,260). Conclusão: Não houve relação entre as funções do assoalho pélvico e a mobilidade nas participantes avaliadas.

Introduction: Population aging grows every year and, consequently, there are physiological adaptations of the organism such as a decrease in gait speed, stability, and postural adaptation, in addition to a loss of muscle integrality, which can lead to several changes, including pelvic floor dysfunctions and impaired mobility. Objective: to associate pelvic floor function with mobility in elderly women. Materials and methods: this cross-sectional study consisted of women over 60 from the city of Bauru /SP. The Research Ethics Committee (number 4.040.883) approved the study, and all volunteers signed the Informed Consent Form and responded to questionnaires for sociodemographic characterization and verification of complaints of pelvic floor dysfunction. Mobility assessment was performed by gait using the 14-meter walkway and analysis of the kinematic parameters using the biological signal acquisition module and a triaxial accelerometer positioned on the lateral malleolus and the evaluation battery Short Physical Performance Battery. Results: A total of 13 women were evaluated (7 in the group with pelvic dysfunction and 6 in the control group) with a mean age of 64± 6,3 years. 54% of women reported urinary incontinence, 8% prolapse, 15% fecal incontinence and 8% sexual dysfunction. In the results of the SPPB, 92% of the volunteers had good ability, and 8% had low ability. In the gait assessment, there were no statistical statistics between the groups (p = 0.260). Conclusion: There was no relation between pelvic floor function and mobility in the evaluated participants.

Effect of different residential settings on gait kinematic parameters in older adults with cognitive impairment.

OBJECTIVE: To compare the parameters of gait kinematics of older adults with cognitive impairment who live in community dwellings or those living or spending most of the time in non-family environment settings. METHODS: The sample was composed of 33 older adults of both sexes with cognitive impairment. Participants were separated into three groups: a community-dwelling older adult group comprised of 11 subjects; a semi-institutionalized older adult group comprised of 10 older adults attended in a geriatric daycare institution; and an institutionalized older adult group comprised of 12 older adults living in long-term institutions. Gait kinematics were recorded by pressure sensors (footswitches). Fifty gait cycles at self-selected pace were analyzed to obtain: gait speed, stride length, stance, swing, and stride time. The variability of these parameters was also analyzed. RESULTS: MANCOVA identified the main effect of groups (p < 0.001). Gait speed of older adults living in long-term institutions and older adults attended in geriatric daycare institutions was slower than community-living older adults (p < 0.001 and p = 0.04, respectively). Swing and stride time variability was higher in older adults living in long-term institutions (p = 0.003 and p = 0.001) and in older adults attended in geriatric daycare institutions (p = 0.02 and p = 0.001) than in community-dwelling older adults. CONCLUSION: The most important finding was that older adults with cognitive impairment who need non-family residential setting care had higher gait kinematics abnormalities, which may increase the risk of falls, compared to those who live in the community.

Time-Response of Photobiomodulation Therapy by Light-Emitting Diodes on Muscle Torque and Fatigue Resistance in Young Men: Randomized, Double-Blind, Crossover and Placebo-Controlled Study.

Background: Photobiomodulation therapy (PBMT) by lasers or light-emitting diodes (LEDs) has been used in the last two decades to increase muscle performance in humans. The main findings of PBMT on muscle performance are increment in torque and number of muscle contractions, and fatigue resistance in high-intensity exercises. Although there are suggested light energies to be followed, the literature has also pointed out to a possible time-response of PBMT to increase exercise performance and recovery in humans. Objective: To investigate the possible time-response of PBMT by LEDs to increase muscle performance in young men regarding peak torque (PT), rate of torque development (RTD), fatigue resistance, and subjective perception of effort in maximal voluntary isometric contractions (MVIC) of elbow flexion. Methods: This randomized, double-blind, placebo-controlled, crossover trial with two arms enrolled 34 healthy and physically active young men, but 30 (21.10 ± 2.25 years old) completed all procedures. All volunteers were allocated into two equal arms (groups): PBMT (60 J; 1152 mW; 52 sec; and 166.75 cm2) applied on biceps brachii by a flexible array of LEDs, and placebo treatment. Each arm (n = 15) investigated the time-response (5 min, 1 h, 3 h, and 6 h) of PBMT in a randomized, double-blind, and crossover manner on the PT, RTD, fatigue resistance, and subjective perception of effort. Results: There were no significant results (p > 0.05) for all comparisons within and between groups regarding PT, RTD, fatigue resistance, and subjective perception of effort in MVIC of the elbow flexion in all time-response tested (5 min, 1 h, 3 h, and 6 h) before or after fatigue test. Only RTD did not decay significantly after fatigue test at all time-responses for PBMT group. Conclusions: PBMT was not effective to increase muscle performance and decrease fatigue to demonstrate the possible time-response in humans.

Muscle recruitment and co-contraction when walking in young women with chronic lumbar pain / Recrutamento e cocontração muscular durante a marcha em mulheres jovens com dor lombar crônica / Reclutamiento y co-contracción muscular durante la marcha en mujeres jóvenes con dolor lombar crónica

Abstract Introduction: The lumbar pain is the main musculoskeletal complaint reported by the active population, and it prevents daily activities such as walking. Objective: To assess muscle recruitment and the co-contraction of the trunk muscles during different walking speed in individuals with and without chronic lumbar pain. Method: Thirty-four sedentary young women attended the study, in which 18 belonged to the lumbar pain team (LPT) and 16 to the team without lumbar pain (WLP). We assessed the electromyography activity of the internal oblique (IO) local muscle and lumbar multifidus (MUL), and global external oblique (EO), abdominal rectus (AR) and lumbar iliocostalis (LIC), during walking. The electromyography analysis was performed from the average of the linear envelope value, normalized by the peak of muscle activation. The muscle co-contraction (IO/MUL, EO/LIC, AR/LIC, IO/EO, and the abdominal/paravertebral muscle groups) was calculated with the Falconer and Winter formula. The Shapiro-Wilk test, Multivariate Analysis, mixed Variance Analyses with Bonferroni post-hoc, and Pearson (p < 0.05) correlation coefficient were made by the statistical analysis. Results: In the WLP we could notice that the higher the speed, the higher the MUL activation. The co-contraction data demonstrated that IO/MUL muscles activate 20% more in the LPT, during the preferred speed; however, in the WLP, the results showed that the higher the walking speed, the higher the EO/LIC (21.8%) and IO/MUL (17.8%) muscles activation. Conclusion: The recruitment of local muscles doesn't differ among the evaluated groups and conditions; however, in WLP, the higher the MUL muscle action, the higher the walking speed.

Resumo Introdução: A dor lombar (DL) é a principal queixa musculoesquelética relatada na população ativa e incapacita atividades do cotidiano, como a marcha. Objetivo: Avaliar o recrutamento e co-contração dos músculos do tronco durante diferentes velocidades de marcha em indivíduos com e sem DL crônica. Método: Participaram 34 mulheres jovens, sedentárias, 18 compuseram o grupo DL (GDL) e 16 o grupo sem DL (GC). Foi avaliada a atividade eletromiográfica dos músculos locais oblíquo interno (OI) e multífido lombar (MUL), e globais oblíquo externo (OE), reto abdominal (RA) e iliocostal lombar (ICL), durante a marcha. A análise eletromiográfica foi realizada a partir da média do valor de envelope linear, normalizada pelo pico de ativação muscular. A co-contração muscular (OI/MUL, OE/ICL, RA/ICL, OI/OE e os grupos musculares abdominais/ paravertebrais) foi calculada com a fórmula de Falconer e Winter. A análise estatística foi feita por meio do teste Shapiro-Wilk, Análise Multivariada, Análise de Variância mista com pos-hoc bonferroni e coeficiente de correlação de Pearson (p < 0,05). Resultados: No GC podemos perceber que, quanto maior a velocidade, maior a ativação do MUL. Os dados de co-contração demonstraram que os músculos OI/MUL ativam 20% a mais no GDL, durante a velocidade de preferência, no GC, os resultados mostram que quanto maior a velocidade de marcha, maior a ativação dos músculos OE/ICL (21,8%) e OI/MUL (17,8%). Conclusão: O recrutamento dos músculos não difere entre os grupos e condições, contudo foi observado no GC que quanto maior a ação do músculo MUL maior é a velocidade de marcha.

Resumen Introducción: El dolor lumbar (DL) es la principal queja musculoesquelética relatada e incapacita actividades de lo cotidiano, como la marcha. Objetivo: Evaluar el reclutamiento y la co-contracción músculos del tronco durante diferentes velocidades de marcha en individuos con y sin DL. Método: Participaron 34 mujeres jóvenes, sedentarias, 18 compusieron grupo DL (GDL) y 16 grupo sin DL (GC). Se evaluó la actividad electromiográfica de los músculos oblicuo interno (OI) y externos (OE), multífido lumbar (MUL), recto abdominal (RA) e iliocostal lumbar (ICL) durante la marcha. El análisis electromiográfico fue realizado a partir del promedio del valor de sobre lineal, normalizado por el pico de activación muscular. La cocontracción muscular (OI/MUL, OE/ICL, RA/ICL, OI/OE y grupos de músculos abdominales/paravertebrales) se calculó utilizando la fórmula Falconer y Winter. El análisis estadístico fue realizado por Shapiro-Wilk, Análisis Multivariado, Análisis de Variedad mixta con pos-hoc bonferroni y coeficiente de correlación de Pearson (p < 0,05). Resultados: En el GC podemos percibir que, cuanto mayor es la velocidad, mayor es la activación del MUL. Los datos de co-contracción demostraron que los músculos OI/MUL activan un 20% más en el GDL, durante la velocidad de preferencia, sin embargo, en el GC, los resultados muestran que cuanto mayor la velocidad de marcha, mayor la activación de los músculos OE / ICL (21,8%) y OI/MUL (17,8%). Conclusión: El reclutamiento de los músculos no difiere entre los grupos y condiciones, contenido observado en el GC que cuanto mayor es la acción del músculo MUL mayor es la velocidad de marcha.

The ability of gait kinematic parameters to predict falls in older adults with cognitive impairments living in long term institutions.

BACKGROUND: Cognitive impairments reduce adaptive responses and may increase the risk of falls. OBJECTIVES: To compare gait kinematics in older adults with cognitive impairments living in long term institutions and to identify the ability of gait kinematics to predict falls in older adults with cognitive impairments living in long term institutions. METHODS: Data of 23 older adults with cognitive impairments living in long term institutions were considered for this study. Fifty gait cycles were recorded during walking at a self-selected pace using footswitches sensors. The variables considered for the analysis were: speed; stride length; stance, swing and stride time; and the variability of these parameters. Fall status was recorded for a 6 month-period. FINDINGS: MANOVA found group effect (p = 0.025) for gait kinematics comparisons. Variability of stance (p = 0.01) and swing (p = 0.012) and stride time (p < 0.001) were higher in older fallers. Speed of older fallers was 31.8% slower than those of the non-fallers (p < 0.001). The kinematic variables that were able to predict falls were: stride time variability (p < 0.001), threshold of 0.4 s, sensitivity of 50% and specificity of 100%; and gait speed (p < 0.001), threshold of 0.65 m·s-1, sensibility and specificity of 50%. INTERPRETATION: Older adults living in an assisted living facility with a history of falls demonstrate increased kinematic variability while walking. However, the ability of gait kinematic parameters to predict falls was found to be weak. The results suggested that gait kinematic parameters are weak predictors of falls in older adults with cognitive impairments living in long term institutions.

Hip, Knee, and Ankle Functional Demand During Habitual and Fast-Pace Walking in Younger and Older Women.

This study compared functional demand (FD) between older and younger women walking at habitual and fast speed and determined strength thresholds necessary to maintain FD below 80%. FD was calculated by expressing walking flexion and extension joint torques of the ankle, knee, and hip as a percentage of maximal strength. Young women had an average FD of 65% across joint actions and speeds, whereas older women had FD of 90%. In older women, the greatest FD occurred in the hip musculature. The hip, knee, and ankle extensor strengths required to maintain FD below 80% were 1.66, 1.86, and 0.57 Nm/kg, and flexor strengths were 1.24, 0.49, and 0.69 Nm/kg, respectively. Older women have limited functional reserve to increase gait speed and rely heavily on available hip strength during walking. This study identifies strength targets for the hip, knee, and ankle that will assist in maintaining FD of older women at a sustainable level.

Contribution of hip abductor-adductor muscles on static and dynamic balance of community-dwelling older adults.

BACKGROUND: The previous studies have investigated causes of and risk factors for falls and impairment of functional capability in older adults. However, the biomechanical factors involved in functional performance and postural control, and the contribution of hip muscles, are still unknown. AIMS: The aim of the present study was to verify the association between the muscle function of hip abductors and adductors and static and dynamic balance, in a narrow base of support, in community-dwelling older adults. METHODS: Eighty-one older adults, including both women and men, were evaluated. Tandem gait and single-leg stance were used to assess static and dynamic balance, and an isokinetic dynamometer was used to analyze muscle function (peak torque and rate of torque development according to body weight). Data were analyzed by a multivariate linear regression test without adjustment and with adjustment using two models: adjustment I (sex) and adjustment II (age). RESULTS: There was a statistically significant association between peak torque of abductor in single-leg stance and tandem gait speed. The PT of hip adductors contributed to static balance performance, in a narrow base of support from the unadjusted data and from the adjusted data by sex. CONCLUSION: The findings of the present study are relevant, because if deficits in balance and functionality in older adults can be linked to a decline in maximum muscle strength of hip abductors, this parameter can be treated to maintain independence in older adults for as long as possible.

Is it possible to predict falls in older adults using gait kinematics?

BACKGROUND: Gait kinematic parameters have been reported as an important clinical tool to assess the risk of falls in older adults. However, the ability of these parameters to predict falls in the older population is still unclear. OBJECTIVE: To identify the ability that gait kinematic parameters present to predict fall in older adults. METHODS: Data from 102 older adults, who live in a community setting, were considered for this study. For data collection, older subjects had to walk on a 14 meter-walkway in their preferred gait speed. The incidence of falls was recorded at baseline together with gait kinematics and then every three months during the period of the study. The ability of gait kinematic parameters to predict falls was tested using the ROC curve. RESULTS: Stance time variability, swing time, and stride length presented a sensitivity to predict falls in older adults higher than 70%. CONCLUSION: Gait kinematic parameters, such as stance variability, swing time, and stride length may predict future falls in older adults.

Efeito imediato de uma sessão de treinamento do método Pilates sobre o padrão de cocontração dos músculos estabilizadores do tronco em indivíduos com e sem dor lombar crônica inespecífica / Efecto inmediato de una sesión de entrenamiento del método Pilates sobre el estándar de cocontracción de los músculos estabilizadores del tronco en individuos con y sin dolor lumbar crónico inespecífico / Immediate effect of a Pilates method exercise session on the co-contraction pattern of the trunk stabilizing muscles in individuals with and without nonspecific chronic low back pain

RESUMO Este estudo teve por objetivo analisar o efeito imediato de uma sessão de exercícios do método Pilates sobre o padrão de cocontração (agonista/antagonista) dos músculos superficiais (iliocostal lombar e reto abdominal) e profundos (oblíquo interno e multífido) do tronco em indivíduos com e sem dor lombar durante teste de resistência muscular localizada. Participaram do estudo sujeitos adultos, de ambos os sexos, com idade entre 19 e 59 anos, separados em dois grupos: grupo com dor lombar (n=9) e grupo sem dor lombar (n=9). Foram coletados os sinais eletromiográficos dos músculos: oblíquo interno (OI), multífido lombar (MU), iliocostal lombar (IL) e reto abdominal (RA), durante as contrações isométricas voluntárias máximas e o teste de Biering-Sorensen antes e após a realização do protocolo de exercícios do método Pilates. Foi calculada a cocontração entre OI/MU direito e esquerdo (OI/MUd, OI/MUe) e RA/IL direito e esquerdo (RA/ILd e RA/ILe). A cocontração entre OI/MUd, OI/MUe, RA/ILd e RA/ILe foi, respectivamente, 41,4, 32,4, 56 e 31,2% maior no grupo com dor lombar (p<0,001 e p=0,003, p=0,004 e p=0,01). A condição inicial apresentou cocontração antagonista 26,3 e 43,4% maior entre OI/MUd (p=0,023, p=0,03). Uma sessão de treinamento com exercícios do método Pilates foi capaz de reduzir a cocontração entre os músculos do tronco (em indivíduos com e sem dor lombar inespecífica).

RESUMEN Este estudio tuvo por objetivo analizar el efecto inmediato de una sesión de ejercicios del método Pilates sobre el estándar de cocontracción (agonista/antagonista) de los músculos superficiales (iliocostal lumbar y recto abdominal) y profundos (oblicuo interno y multífido) del tronco en individuos con y sin dolor lumbar durante la prueba de resistencia muscular localizada. Participaron del estudio sujetos adultos, de ambos sexos, con edad entre 19 y 59 años, divididos en dos grupos: el grupo con dolor lumbar (n=9) y el grupo sin dolor lumbar (n=9). Fueron recogidas las señales electromiográficas de los músculos: oblicuo interno (OI), multífido lumbar (MU), iliocostal lumbar (IL) y recto abdominal (RA), durante las contracciones isométricas voluntarias máximas y la prueba de Biering-Sorensen antes y después de la realización del protocolo de ejercicios del método Pilates. Fue calculada la cocontracción entre OI/MU derecho e izquierdo (OI/MUd, OI/MUi) y RA/IL derecho e izquierdo (RA/ILd y RA/ILi). La cocontracción entre OI/MUd, OI/MUi, RA/ILd y RA/ILi fue, respectivamente, el 41,4, el 32,4, el 56 y el 31,2% más grande en el grupo con dolor lumbar (p<0,001 y p=0,003, p=0,004 y p=0,01). La condición inicial presentó cocontracción antagonista el 26,3 y el 43,4% más grande entre OI/MUd (p=0,023, p=0,03). Una sesión de entrenamiento con ejercicios del método Pilates fue capaz de reducir la cocontracción entre los músculos del tronco (en individuos con y sin dolor lumbar inespecífico.

ABSTRACT This study aimed to analyze the immediate effect of a Pilates method exercise session on the co-contraction pattern (agonist/antagonist) of the superficial (iliocostalis lumborum and rectus abdominis) and deep (internal oblique and multifidus) muscles of the trunk in individuals with and without low back pain during local muscle endurance test. Participated in the study adult subjects of both gender, aged between 19 and 59 years, separated into two groups: the group with low back pain (n=9) and the group without low back pain (n=9). Electromyographic signals of the following muscles were collected: internal oblique (IO), multifidus lumborum (MU), iliocostalis lumborum (IL) and rectus abdominis (RA), during maximal voluntary isometric contractions and Biering-Sorensen test, before and after the exercise protocol performance of the Pilates method. The co-contractions between IO/MU right and left (IO/MUr, IO/MUl) and RA/IL right and left (RA/ILr and RA/ILl) were calculated. The co-contraction between IO/MUr, IO/MUl, RA/ILr and RA/ILl was respectively 41.4, 32.4, 56 and 31.2% higher in the group with low back pain (p<0.001 and p=0.003, p=0.004 and p=0.01). The initial condition presented antagonist co-contraction 26.3 and 43.4% higher between IO/MUr (p=0.023, p=0.03). A training session with Pilates method exercises was able to reduce co-contraction between the trunk muscles (in individuals with and without nonspecific low back pain).

Análise bilateral da resposta muscular antecipatória do tronco na dor lombar recorrente / Bilateral analysis of the anticipatory trunk muscle response in recurrent low back pain

Introdução: a literatura aponta controvérsias sobre a estabilização proporcionada pela ativação antecipatória dos músculos profundos do tronco e as evidências baseadas na análise bilateral do tempo de reação (onset) muscular de sujeitos com dor lombar são escassas. Objetivos: comparar o onset muscular do tronco entre sujeitos saudáveis e com dor lombar recorrente, bem como, comparar o onset muscular entre os lados do tronco nestas populações. Métodos: 19 sujeitos com dor lombar e 19 sujeitos saudáveis executaram o teste de elevação do membro superior dominante, no qual foram coletados os sinais eletromiográficos dos músculos do tronco. Resultados: na comparação entre os grupos, sujeitos com dor lombar apresentaram respostas mais rápidas do oblíquo interno contralateral ao membro elevado (p= 0,016). Na comparação entre os lados, sujeitos saudáveis apresentaram diferença significativa entre o onset dos oblíquos internos (p= 0,043). Conclusão: a dor lombar recorrente provoca alteração das respostas motoras geradas pela perturbação postural.

Introduction: The literature showed controversies about the stabilization provided by the anticipatory activation of the deep trunk muscles and the evidence based on the bilateral analysis of the muscle reaction time (onset) of subjects with low back pain is poor. Objectives: to compare the trunk muscle onset between healthy subjects and people with recurrent low back pain, as well as to compare the onset between the trunk sides in these populations. Methods: 19 subjects with low back pain and 19 healthy subjects performed the arm elevation test of the dominant upper limb, in which the electromyographic signals of the trunk muscles were collected. Results: in the groups comparison, subjects with low back pain had faster responses of the contralateral internal oblique to the raised limb (p = 0,016). In the comparison between the sides, healthy subjects presented significant difference between the onset of the internal oblique (p = 0,043). Conclusion: recurrent low back pain causes alteration of the motor responses generated by the postural destabilization.

Discriminatory Ability of Lower-Extremity Peak Torque and Rate of Torque Development in the Identification of Older Women With Slow Gait Speed.

The aim was to compare torque and rate of torque development of lower limb muscles between older women with functional and slow gait speeds to determine which muscle group is the best predictor of functional gait speed, and to establish strength thresholds needed for functional walking speed. Torque and rate of torque development of hip, knee, and ankle muscles were measured in older women who were divided in 2 groups according to gait speed: slow gait speed (<1.22 m·s-1) and functional gait speed (≥1.22 m·s-1). For each muscle group, 3 maximal isometric contractions were performed, and peak torque and rate of torque development were recorded. Older women with slow gait speed had lower peak torque than older women with functional gait speed for hip extension (28%), knee flexion (15%), knee extension (14%), and plantar flexion (16%) (all Ps < .05). Older women with slow gait speed had lower peak rate of torque development for hip flexion (29%), hip extension (37%), knee flexion (34%), knee extension (33%), and plantar flexion (19%) (all Ps < .05). Knee extension peak rate of torque development and hip extension peak torque were the better predictors of functional gait speed with thresholds of 2.96 N·m·s-1·kg-1 and 1.26 N·m·kg-1, respectively.

Quadriceps muscle weakness influences the gait pattern in women with knee osteoarthritis.

BACKGROUND: Osteoarthritis is the most prevalent rheumatic disease in the population and is characterized by limitation of main functional activities of daily living, as the gait. Muscle strength is a variable that may be related to performance in daily tasks.Therefore, we to analyze the gait pattern in individuals with knee osteoarthritis (KOA) and to determine associations of gait variables with the level of muscle strength of knee extensors. METHODS: Sixty-seven female volunteers divided into 2 groups, a KOA group (KOAG, n = 36, 66.69 ± 7.69 years) and control (n = 31, 63.68 ± 6.97 years), participated in the study. The volunteers walked on a 10-m platform at their usual gait speed, using 2 pressure sensors positioned at the base of the hallux and calcaneus. The mean step time, support and double support times, swing time and gait speed were calculated. The evaluation of the quadriceps isometric torque was performed in an extensor chair, with hip and knee flexion at 90°. The procedure consisted of three maximal contractions of knee extension. Peak torque was determined by the highest torque value obtained after the onset of muscle contraction. For statistical analysis, one-way ANOVA and Pearson's correlation were used, with p <  0.05. RESULTS: The KOAG had a 54.76% longer support time, a 13% longer step time (p <  0.001), a 30% decrease in swing time (p <  0.001) and a 10.7% decrease in gait speed (p = 0.001) compared with controls. The quadriceps isometric torque was 34% (p = 0.001) lower in the KOAG. There was a correlation between kinematic variables and quadriceps torque. CONCLUSION: Weakness of the quadriceps muscle in women with KOA influences gait pattern, resulting in reduced speed associated with a shorter swing time and longer support time.

Do cognitive tasks during gait increase the risk of accidents with pedestrians? A study based on electromyographic parameters / Tarefas cognitivas durante a marcha aumentam o risco de acidentes com pedestres? Um estudo baseado em parâmetros eletromiográficos

Abstract Introduction Accidents involving pedestrians are responsible for many cases of serious injuries and deaths. Crossing streets safely requires complex planning and cognitive demand because it is necessary to perform more than one task at a time. Objective The aim of this study was to identify electromyographic changes during gait in young subjects who performed the cognitive tasks concurrently. Methods The study included 17 younger women aged between 18 and 25 years. Data collection was performed on a treadmill. The volunteers were instructed to walk in four different conditions: normal gait (NG), gait with dual easy task (DET), gait with dual hard task (DHT) and gait with dual mixed task (DMT). Results Significant differences were found between the MN condition to the other conditions for all muscles and, during the NG, smaller values of muscle activation were found. Muscle co-contraction between muscles VM / BF showed a significant difference between the conditions of NG and DMT (p = 0.04) and, during the NG, smaller values of co-contraction were observed. Conclusion The data of this study permits to conclude that the competition between motor and cognitive resources significantly affects the levels of muscle activation and co-contraction during gait in young adult women. Thus, we conclude that the performance of dual cognitive tasks while driving can be considered a risk factor for safe driving.

Resumo Introdução Os acidentes de trânsito envolvendo pedestres são responsáveis por muitos casos de lesões graves e óbitos. Atravessar a rua com segurança requer complexo planejamento e demanda cognitiva, pois é necessário realizar mais de uma tarefa ao mesmo tempo. Objetivo O objetivo do presente estudo foi identificar alterações eletromiográficas durante a marcha de indivíduos jovens realizada concomitantemente com tarefas cognitivas. Métodos Participaram do estudo 17 jovens do sexo feminino com idade entre 18 e 25 anos. A coleta de dados foi realizada em esteira ergométrica onde os voluntários realizaram o teste de marcha compostos por quatro condições distintas: marcha normal (MN), marcha com dupla tarefa fácil (DTF), marcha com dupla tarefa difícil (DTD) e marcha com dupla tarefa mista (DTM). Resultados Foram encontradas diferenças significativas entre a condição de MN para as demais condições para todos os músculos, sendo que durante a MN foram encontrados menores valores de ativação muscular. A co-contração muscular entre os músculos VM/BF mostrou diferença significativa entre as condições de MN e DTM (p = 0,04), sendo que durante a MN foram observados menores valores de co-contração. Conclusão Os dados do presente estudo, nos permitem concluir que a competição entre recursos motores e cognitivos afeta, significantemente, os níveis de ativação muscular e co-contração durante a marcha de mulheres adultas jovens. Assim, concluímos que a realização de duplas tarefas cognitivas durante a marcha pode ser considerada um fator de risco para o desempenho seguro da mesma, podendo ocasionar maior risco de acidentes aos pedestres.

Applying different mathematical variability methods to identify older fallers and non-fallers using gait variability data.

BACKGROUND: The clinical assessment of gait variability may be a particularly powerful tool in the screening of older adults at risk of falling. Measurement of gait variability is important in the assessment of fall risk, but the variability metrics used to evaluate gait timing have not yet been adequately studied. OBJECTIVES: The aims of this study were (1) to identify the best mathematical method of gait variability analysis to discriminate older fallers and non-fallers and (2) to identify the best temporal, kinematic parameter of gait to discriminate between older fallers and non-fallers. METHODS: Thirty-five physically active volunteers participated in this study including 16 older women fallers (69.6 ± 8.1 years) and 19 older women non-fallers (66.1 ± 6.2 years). Volunteers were instructed to walk for 3 min on the treadmill to record the temporal kinematic gait parameters including stance time, swing time and stride time by four footswitches sensors placed under the volunteers' feet. Data analysis used 40 consecutive gait cycles. Six statistical methods were used to determine the variability of the stance time, swing time and stride time. These included: (1) standard deviation of all the time intervals; (2) standard deviation of the means of these intervals taken every five strides; (3) mean of the standard deviations of the intervals determined every five strides; (4) root-mean-square of the differences between intervals; (5) coefficient of variation calculated as the standard deviation of the intervals divided by the mean of the intervals; and (6) a geometric method calculated based on the construction of a histogram of the intervals. RESULTS: The standard deviation of 40 consecutive gait cycles was the most sensitive (100 %) and specificity (100 %) parameter to discriminate older fallers and non-fallers. CONCLUSION: The standard deviation of stance time is the kinematic gait variability parameter that demonstrated the best ability to discriminate older fallers from non-fallers. PROTOCOL NUMBER OF BRAZILIAN REGISTRY OF CLINICAL TRIALS: RBR-6rytw2.

The effects of a simultaneous cognitive or motor task on the kinematics of walking in older fallers and non-fallers.

Human gait has been widely investigated under dual-task conditions because it has been demonstrated to be an important way to uncover differences in gait biomechanics between older fallers and non-fallers. However, exactly how simultaneous tasks affect the kinematics of walking remains unclear. In the present study, gait kinematic properties of older fallers and non-fallers were compared under cognitive and motor dual-task conditions. The gait kinematic properties of interest were recorded under three different conditions: walking at preferred speed, walking when performing a cognitive task (naming animals), and walking when performing a motor task (transferring a coin from one pocket to the other). The following variables were analyzed: gait speed, cadence, stride time, step length, single support, stride time variability, and the dual-task cost. In addition, functional balance was evaluated by means of the Balance Evaluation - Systems Test (BESTest). Two-way repeated-measures ANOVAs revealed significant main effects of walking conditions. However, no significant main effects of group (fallers vs. non-fallers) and no significant interaction effects between group and walking condition were observed. The BESTest revealed that functional balance in fallers was worse than in non-fallers. The cognitive task leads to more significant changes in gait kinematics than does a motor task and the step length and stride time variability were variables more sensitive to that cognitive influence.

Neuromuscular control strategies of the trunk antagonist muscles during the Biering-Sorensen test in individuals with recurrent low back pain and healthy subjects

Abstract OBJECTIVES To compare the activation pattern of the trunk antagonistic muscles and also the myoelectric manifestations of muscle fatigue between subjects with and without recurrent non-specific low back pain, during the fatigue provocation of the erector spinae. METHODS The study involved 19 subjects with recurrent low back pain with a non-specific cause (seven men, 12 women, 38.53 ± 8.12 years, 68.35 ± 18.12 kg, 1.66 ± 0.09 m), and 19 healthy subjects (seven men, 12 women, 40.42 ± 8.63 years, 69.57 ± 12.76 kg, 1.64 ± 0.07 m). The electromyographic signal of the internal oblique, lumbar multifidus, rectus abdominis and lumbar iliocostalis muscles, bilateral, were collected during Biering-Sorensen test execution. RESULTS The group with low back pain showed a lower co-contraction rate of the internal oblique/lumbar multifidus (p = 0.006) and lower activation amplitude of the internal oblique (p = 0.019), both on the right side when compared to the group without low back pain. No differences were observed between the groups for muscle fatigue indicators (p > 0.05). CONCLUSION When the erector spine muscle fatigue occurs - even when the groups were similar as to the ability of extensors muscles to resist fatigue - differences were found between subjects with and without low back pain regarding the recruitment pattern of the task antagonist muscle, because subjects with low back pain showed lesser activation and co-contraction in relation to the healthy group.

Efeito agudo de exercícios do método Pilates na ativação dos músculos do tronco de pessoas com e sem dor lombar / Acute effect of Pilates method exercises on trunk muscles activation in people with and without low back pain

Introdução: O método Pilates é indicado para reabilitação de pacientes com dor lombar inespecífica (DLI). Contudo, o efeito deste treinamento no padrão de recrutamento muscular é desconhecido. Objetivo: Analisar o efeito agudo do método Pilates na ativação dos músculos do tronco em indivíduos com e sem DLI. Métodos: Participaram do estudo 18 sujeitos, separados em dois grupos: grupo com DLI e sem DLI. No primeiro dia de coleta, foram obtidos: dados pessoais, medidas antropométricas e familiarização com os exercícios. No segundo dia, foram realizados: teste de elevação do braço, teste de Biering-Sorensen, os exercícios e reavaliação. Foram coletados os sinais eletromiográficos dos músculos: oblíquo interno, multífido lombar, iliocostal lombar e reto abdominal. Resultados: Após o treinamento, o grupo com DLI apresentou, no teste de Biering-Sorensen, maior ativação do iliocostal lombar (p=0,016) e menor ativação do oblíquo interno (p=0,031). Conclusão: Uma sessão do método Pilates foi capaz de alterar o padrão de recrutamento dos músculos do tronco em indivíduos com DLI.

Background: Pilates method is prescribed for rehabilitation of patients with nonspecific low back pain (LBP). However, the effect of this training on trunk muscles activation is unknown. Objective: To analyze the acute effect of Pilates method on trunk muscles activation in subjects with and without LBP. Methods: Participated of the study 18 people, separated into two groups: group with LBP and without LBP. In the first day of data collection were recorded: personal data, anthropometrics measures and familiarization was performed. In the second day of data collection were performed the tests: test of arm elevation, Biering-Sorensen, exercises and reassessment. Electromyographic signal of internal oblique, multifidus, iliocostalis lumborum, and rectus abdominal were recorded. Results: The muscles iliocostalis lumborum had higher activation (p=0,016) during Biering-Sorensen test in LBP, while internal oblique had lower activation (p=0,031) after the training in LBP. Conclusion: A single session of Pilates method was able to generate change on trunk muscles recruitment pattern in people with LBP.

Peak torque, reaction time, and rate of torque development of hip abductors and adductors of older women.

Impaired muscle function at the hip has been implicated to be a major factor related to falls in older adults. Therefore, the aim of this study was to analyze the rate of torque development (RTD), reaction time (RT), and peak torque (PT) of hip abductors and hip adductors in young women (YW), older women nonfallers (ONF), and older women fallers (OF). Eighteen YW and 44 older women divided among OF (n = 20) and ONF (n = 24) performed maximum isometric hip abductor and adduction contractions on a dynamometer. YW had 40% greater PT and 61.5% greater RTD for hip abductors than the ONF. Compared with OF, YW had 47.5% greater PT and 68% greater RTD. OF showed less RTD at 150 ms (31%) and 200 ms (34.5%) than ONF for hip abductors. PT of hip adductors was 52% greater in YW than in the two older groups, whereas RTD was 71% greater. OF showed less RTD than ONF for hip abductors according to standardized effect sizes. No RT differences were observed between the three groups. We conclude that older women (OF and ONF) have less strength and ability to develop force rapidly than YW for hip abductors and adductors. Low hip strength and slowed force development in ONF during hip abduction may increase fall risk in older women.