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BACKGROUND: The vertical jump can be analyzed based on the flight time achieved by the individual. This measurement can be obtained using a force platform or a three-dimensional infrared camera system, but such equipment is expensive and requires training for data collection and processing. Thus, this study aimed to evaluate the accuracy and reliability of using a smartphone and the Kinovea software compared with a force platform as a method of vertical jump analysis. METHODS: For this purpose, two independent evaluators analyzed videos of bipodal and unipodal vertical jumps by counting the variables among participants. The participants performed three consecutive jumps in bipodal and unipodal conditions with the dominant and non-dominant legs. RESULTS: The intra-rater analysis for bipodal jumps was found to have excellent reproducibility (ICC = 0.903 to 0.934), whereas for unipodal jumps, the reproducibility was moderate to excellent (ICC = 0.713 to 0.902). The inter-rater analysis showed that for bipodal jumps, the reproducibility is substantial to excellent (ICC = 0.823 to 0.926), while for unipodal jumps, it is moderate (ICC = 0.554 to 0.702). CONCLUSIONS: Therefore, it can be concluded that the vertical jump evaluation can be performed using the smartphone-Kinovea system. However, the same evaluator should carry out the evaluation to maintain reliable indices.
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This study aims to estimate the optical properties, absorption (µ a), and reduced scattering (µ s ') coefficients of ex vivo human skin through the individual typology angle (ITA) by only using the skin color parameters. Human skin samples were grouped according to their ITA value and measured using a colorimeter for validation. An integrating sphere and the inverse adding-doubling algorithm were applied to compute the samples µ a and µ s '. The µ a increases as the ITA decreases. An axis swap was performed to generate the µ a versus the ITA for all wavelengths between 500 nm and 800 nm with a spectral resolution of 10 nm. Linearization was performed and a correlation was found. An equation to fit µ a based solely on the ITA values was estimated. The µ s ' does not change with ITA, but it could be fit with an inverse power law as a function of the wavelength. Both equations have a coefficient of determination (R 2) higher than 0.93, indicating a good agreement with our model. An experimental model to estimate the absorption and reduced scattering coefficients of ex vivo human skin through ITA was found. The model has high agreement with the experimental data, with an R 2 between 0.932 and 0.997, and these findings may be relevant for photobiomodulation and light treatment applications to estimate the effect of the melanin on the therapy.
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Algoritmos , Colorimetria , Humanos , Pele , Pigmentação da PeleRESUMO
OBJECTIVES: To evaluate the impact of the additional use of early neuromuscular electrical stimulation (NMES) on an early mobilization (EM) protocol. DESIGN: Randomized controlled trial. SETTING: ICU of the Clinical Hospital of Ribeirão Preto, University of São Paulo, Brazil. PATIENTS: One hundred and thirty-nine consecutive mechanically ventilated patients were included in the first 48 hours of ICU admission. INTERVENTIONS: The patients were divided into two groups: EM and EM+NMES. Both groups received EM daily. In the EM+NMES group, patients additionally received NMES 5 days a week, for 60 minutes, starting in the first 48 hours of ICU admission until ICU discharge. MEASUREMENTS AND MAIN RESULTS: Functional status, muscle strength, ICU and hospital length of stay (LOS), frequency of delirium, days on mechanical ventilation, mortality, and quality of life were assessed. Patients in the EM+NMES group presented a significant higher score of functional status measured by the Functional Status Score for the ICU scale when compared with the EM group in the first day awake: 22 (15-26) versus 12 (8-22) (p = 0.019); at ICU discharge: 28 (21-33) versus 18 (11-26) (p = 0.004); and hospital discharge: 33 (27-35) versus 25 (17-33) (p = 0.014), respectively. They also had better functional status measured by the Physical Function Test in the ICU scale, took less days to stand up during the ICU stay, and had a significant shorter hospital LOS, lower frequency of ICU-acquired weakness, and better global muscle strength. CONCLUSIONS: The additional application of early NMES promoted better functional status outcomes on the first day awake and at ICU and hospital discharge. The patients in the EM+NMES group also took fewer days to stand up and had shorter hospital LOS, lower frequency of ICU-acquired weakness, and better muscle strength. Future studies are still necessary to clarify the effects of therapies associated with EM, especially to assess long-term outcomes.
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Estado Terminal , Deambulação Precoce , Estado Terminal/terapia , Estimulação Elétrica , Estado Funcional , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Qualidade de Vida , Respiração ArtificialRESUMO
INTRODUCTION: Severe burns benefit from skin grafting, and grafting surgery is of great importance in the treatment of these injuries. As a result, there is formation of an additional wound at the donor site, which is painful and susceptible to infection. However, the therapeutic approach to these problems at donor sites for skin grafting is insufficiently explored in the literature. AIM: To evaluate electrical stimulation of the donor sites of burn patients treated by grafting surgery. METHODS: This work evaluated 30 donor sites of cutaneous graft burn patients treated with high-voltage electrical stimulation. Subjects were randomized into two groups: electrical stimulation (GES), treated with electrostimulation (50min, 100Hz, twin pulses 15 us, monophasic), and the sham group (GS), treated by the same procedures but without current. Pain was assessed by visual analog scale daily before and after the electrical stimulation. The time elapsed until complete epithelization was evaluated (time of primary dressing detached spontaneously). Skin temperature was measured by thermography. The characteristics of donor sites were qualitatively evaluated using images and the plug-in CaPAS® (Carotid Plaque Analysis Software). RESULTS: The results showed a significant decrease in pain, which was absent on the third day in the GES and the sixth day in the GS. The time the primary dressing detached spontaneously in days decreased (p<0.05) (4.7±0.2) compared to the GS group (7.0±1.3). Donor site healing characteristics such as vascularization, pigmentation, height, the quantity of crust formed, irregularities, and the quality of healing was better in the GES; moreover, homogeneity and inertia of the images confirmed higher healing quality. CONCLUSION: As a result of the study, the technology shows promise and merits a larger study with objective assessments and different physical variables.
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Queimaduras/cirurgia , Terapia por Estimulação Elétrica/métodos , Dor Pós-Operatória/fisiopatologia , Transplante de Pele/métodos , Sítio Doador de Transplante , Cicatrização , Adulto , Cicatriz/etiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reepitelização , Couro Cabeludo/cirurgia , Coxa da Perna/cirurgia , Adulto JovemRESUMO
Muscular strength (MS) and jump power (JP) tests are used to assess athletic ability and measure the effectiveness of training programs. However, their use in various sport modalities needs to be investigated further. This study aimed to explore the changes in MS and JP during three different moments of a macrocycle training session and verify the validity of the tests used to predict the effectiveness of basketball training programs. Methods: During macrocycle training (three different moments), sixteen basketball players were evaluated for MS (measured using isokinetic dynamometry at the speed of 60°/s) during concentric contraction of knee flexor and extensor muscles and JP, using countermovement vertical jump (CMVJ) on a force platform. Results: Peak torque and maximal work values for knee extension and flexion showed no differences, during the three moments analyzed. Additionally, no changes were observed for CMVJ. Conclusions: Our results suggest that the effectiveness of basketball training programs does not seem to be related to the performance achieved by athletes on the tests used. Moreover, the lack of changes in MS and JP values during the macrocycle could be related to the training structure used; volume, intensity, density and workload specificity.(AU)
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Humanos , Masculino , Adolescente , Basquetebol , Teste de Esforço/métodos , Força Muscular/fisiologia , Atletas , Exercício Físico/fisiologiaRESUMO
BACKGROUND: Cryotherapy is a widely used technique in physical therapy clinics and sports. However, the effects of cryotherapy on dynamic neuromuscular control are incompletely explained. OBJECTIVES: To evaluate the effects of cryotherapy applied to the calf, ankle and sole of the foot in healthy young adults on ground reaction forces during gait initiation. METHOD: This study evaluated the gait initiation forces, maximum propulsion, braking forces and impulses of 21 women volunteers through a force platform, which provided maximum and minimum ground reaction force values. To assess the effects of cooling, the task--gait initiation--was performed before ice application, immediately after and 30 minutes after removal of the ice pack. Ice was randomly applied on separate days to the calf, ankle and sole of the foot of the participants. RESULTS: It was demonstrated that ice application for 30 minutes to the sole of the foot and calf resulted in significant changes in the vertical force variables, which returned to their pre-application values 30 minutes after the removal of the ice pack. Ice application to the ankle only reduced propulsion impulse. CONCLUSIONS: These results suggest that although caution is necessary when performing activities that require good gait control, the application of ice to the ankle, sole of the foot or calf in 30-minute intervals may be safe even preceding such activities.
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Crioterapia , Marcha/fisiologia , Perna (Membro)/fisiologia , Feminino , Humanos , Adulto JovemRESUMO
BACKGROUND: Infrared thermography is recognized as a viable method for evaluation of subjects with myofascial pain. OBJECTIVE: The aim of the present study was to assess the intra- and inter-rater reliability of infrared image analysis of myofascial trigger points in the upper trapezius muscle. METHOD: A reliability study was conducted with 24 volunteers of both genders (23 females) between 18 and 30 years of age (22.12 ± 2.54), all having cervical pain and presence of active myofascial trigger point in the upper trapezius muscle. Two trained examiners performed analysis of point, line, and area of the infrared images at two different periods with a 1-week interval. The intra-class correlation coefficient (ICC(2,1)) was used to assess the intra- and inter-rater reliability. RESULTS: With regard to the intra-rater reliability, ICC values were between 0.591 and 0.993, with temperatures between 0.13 and 1.57 °C for values of standard error of measurement (SEM) and between 0.36 and 4.35 °C for the minimal detectable change (MDC). For the inter-rater reliability, ICC ranged from 0.615 to 0.918, with temperatures between 0.43 and 1.22 °C for the SEM and between 1.19 and 3.38 °C for the MDC. CONCLUSION: The methods of infrared image analyses of myofascial trigger points in the upper trapezius muscle employed in the present study are suitable for clinical and research practices.
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Raios Infravermelhos , Síndromes da Dor Miofascial/diagnóstico , Síndromes da Dor Miofascial/fisiopatologia , Músculos Superficiais do Dorso/fisiologia , Termografia/métodos , Pontos-Gatilho/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto JovemRESUMO
BACKGROUND: Infrared thermography is recognized as a viable method for evaluation of subjects with myofascial pain. OBJECTIVE: The aim of the present study was to assess the intra- and inter-rater reliability of infrared image analysis of myofascial trigger points in the upper trapezius muscle. METHOD: A reliability study was conducted with 24 volunteers of both genders (23 females) between 18 and 30 years of age (22.12±2.54), all having cervical pain and presence of active myofascial trigger point in the upper trapezius muscle. Two trained examiners performed analysis of point, line, and area of the infrared images at two different periods with a 1-week interval. The intra-class correlation coefficient (ICC2,1) was used to assess the intra- and inter-rater reliability. RESULTS: With regard to the intra-rater reliability, ICC values were between 0.591 and 0.993, with temperatures between 0.13 and 1.57 °C for values of standard error of measurement (SEM) and between 0.36 and 4.35 °C for the minimal detectable change (MDC). For the inter-rater reliability, ICC ranged from 0.615 to 0.918, with temperatures between 0.43 and 1.22 °C for the SEM and between 1.19 and 3.38 °C for the MDC. CONCLUSION: The methods of infrared image analyses of myofascial trigger points in the upper trapezius muscle employed in the present study are suitable for clinical and research practices. .
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Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Termografia/métodos , Pontos-Gatilho/fisiologia , Músculos Superficiais do Dorso/fisiologia , Raios Infravermelhos , Síndromes da Dor Miofascial/diagnóstico , Síndromes da Dor Miofascial/fisiopatologiaRESUMO
BACKGROUND: Cryotherapy is a widely used technique in physical therapy clinics and sports. However, the effects of cryotherapy on dynamic neuromuscular control are incompletely explained. OBJECTIVES: To evaluate the effects of cryotherapy applied to the calf, ankle and sole of the foot in healthy young adults on ground reaction forces during gait initiation. METHOD: This study evaluated the gait initiation forces, maximum propulsion, braking forces and impulses of 21 women volunteers through a force platform, which provided maximum and minimum ground reaction force values. To assess the effects of cooling, the task - gait initiation - was performed before ice application, immediately after and 30 minutes after removal of the ice pack. Ice was randomly applied on separate days to the calf, ankle and sole of the foot of the participants. RESULTS: It was demonstrated that ice application for 30 minutes to the sole of the foot and calf resulted in significant changes in the vertical force variables, which returned to their pre-application values 30 minutes after the removal of the ice pack. Ice application to the ankle only reduced propulsion impulse. CONCLUSIONS: These results suggest that although caution is necessary when performing activities that require good gait control, the application of ice to the ankle, sole of the foot or calf in 30-minute intervals may be safe even preceding such activities. .
Assuntos
Humanos , Feminino , Adulto Jovem , Crioterapia , Marcha/fisiologia , Perna (Membro)/fisiologiaRESUMO
BACKGROUND: Cryotherapy has been associated with a significant decrease in nerve conduction velocity and muscle contraction with possible effects on exercise and physical training. OBJECTIVES: To quantify the electromyographic response of the lateral gastrocnemius, tibialis anterior, fibularis longus, rectus femoris and gluteus medius to ankle inversion following cold water immersion. METHOD: The peak values of the root mean square (RMS) were obtained from 35 healthy and active university subjects after the use of a tilt platform to force the ankle into 30° of inversion before, immediately after, and 10, 20, and 30 minutes after water immersion at 4±2°C, for 20 minutes. The Shapiro-Wilk test, repeated measures analysis, Bonferroni's post-hoc, and linear regression analysis provided the results. RESULTS: Peak RMS was significantly lower at all times after cold water immersion, with residual effect of up to 30 minutes, when compared to pre-immersion for all muscles, except for immediate post-immersion for the gluteus medius. CONCLUSIONS: After cold water immersion of the ankle, special care should be taken in activities that require greater neuromuscular control.
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Tornozelo , Temperatura Baixa , Eletromiografia , Extremidade Inferior/fisiologia , Movimento , Músculo Esquelético/fisiologia , Humanos , Masculino , Músculo Esquelético/inervação , Água , Adulto JovemRESUMO
BACKGROUND: Cryotherapy has been associated with a significant decrease in nerve conduction velocity and muscle contraction with possible effects on exercise and physical training. OBJECTIVES: To quantify the electromyographic response of the lateral gastrocnemius, tibialis anterior, fibularis longus, rectus femoris and gluteus medius to ankle inversion following cold water immersion. METHOD: The peak values of the root mean square (RMS) were obtained from 35 healthy and active university subjects after the use of a tilt platform to force the ankle into 30° of inversion before, immediately after, and 10, 20, and 30 minutes after water immersion at 4±2°C, for 20 minutes. The Shapiro-Wilk test, repeated measures analysis, Bonferroni's post-hoc, and linear regression analysis provided the results. RESULTS: Peak RMS was significantly lower at all times after cold water immersion, with residual effect of up to 30 minutes, when compared to pre-immersion for all muscles, except for immediate post-immersion for the gluteus medius. CONCLUSIONS: After cold water immersion of the ankle, special care should be taken in activities that require greater neuromuscular control. .
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Humanos , Masculino , Adulto Jovem , Tornozelo , Temperatura Baixa , Eletromiografia , Extremidade Inferior/fisiologia , Movimento , Músculo Esquelético/fisiologia , Músculo Esquelético/inervação , ÁguaRESUMO
BACKGROUND: The reduction of the pelvic floor muscles (PFM) strength is a major cause of stress urinary incontinence (SUI). OBJECTIVES: To compare active and passive forces, and vaginal cavity aperture in continent and stress urinary incontinent women. METHODS: The study included a total of thirty-two women, sixteen continent women (group 1 - G1) and sixteen women with SUI (group 2 - G2). To evaluate PFM passive and active forces in anteroposterior (sagittal plane) and left-right directions (frontal plane) a stainless steel specular dynamometer was used. RESULTS: The anteroposterior active strength for the continent women (mean±standard deviation) (0.3±0.2 N) was greater compared to the values found in the evaluation of incontinent women (0.1±0.1 N). The left-right active strength (G1=0.43±0.1 N; G2=0.40±0.1 N), the passive force (G1=1.1±0.2 N; G2=1.1±0.3 N) and the vaginal cavity aperture (G1=21±3 mm; G2=24±4 mm) did not differ between groups 1 and 2. CONCLUSION: The function evaluation of PFM showed that women with SUI had a lower anteroposterior active strength compared to continent women.
CONTEXTUALIZAÇÃO: A redução da força dos músculos do assoalho pélvico (MAP) é a maior causa da incontinência urinária de estresse (IUE). OBJETIVO: Comparar as forças ativa e passiva e a abertura da cavidade vaginal em mulheres continentes e com IUE. MÉTODOS: O estudo incluiu um total de 32 mulheres, 16 mulheres continentes (grupo 1 - G1) e 16 mulheres com IUE (grupo 2 - G2). Um espéculo dinamométrico de aço inoxidável foi usado para avaliar as forças ativa e passiva dos MAP nas direções ântero-posterior (plano sagital) e látero-lateral (plano frontal). RESULTADOS: A força ativa ântero-posterior nas mulheres continentes (0,3±0,2 N) foi maior que nas mulheres com IUE (0,1±0,1 N). Não houve diferença entre o G1 e o G2 nos valores de força ativa látero-lateral (G1=0,43±0,1 N; G2=0,40±0,1 N), força passiva (G1=1,1±0,2 N; G2=1,1±0,3 N) e abertura da cavidade vaginal (G1=21±3 mm; G2=24±4 mm). CONCLUSÃO: A avaliação da função dos MAP mostrou que mulheres com IUE tiveram uma menor força ativa ântero-posterior quando comparadas com as mulheres continentes.
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Adulto , Feminino , Humanos , Diafragma da Pelve/fisiopatologia , Incontinência Urinária por Estresse/fisiopatologia , Diafragma da Pelve/fisiologiaRESUMO
BACKGROUND: In the literature, there are several experimental models that induce scoliosis in rats; however, they make use of drugs or invasive interventions to generate a scoliotic curve. OBJECTIVES: To design and apply a non-invasive immobilization model to induce scoliosis in rats. METHODS: Four-week old male Wistar rats (85±3.3g) were divided into two groups: control (CG) and scoliosis (SG). The animals in the SG were immobilized by two vests (scapular and pelvic) made from polyvinyl chloride (PVC) and externally attached to each other by a retainer that regulated the scoliosis angle for twelve weeks with left convexity. After immobilization, the abdominal, intercostal, paravertebral, and pectoral muscles were collected for chemical and metabolic analyses. Radiographic reports were performed every 30 days over a 16-week period. RESULTS: The model was effective in the induction of scoliosis, even 30 days after immobilization, with a stable angle of 28±5º. The chemical and metabolic analyses showed a decrease (p<0.05) in the glycogenic reserves and in the relationship between DNA and total protein reserves of all the muscles analyzed in the scoliosis group, being lower (p<0.05) in the convex side. The values for the Homeostatic Model Assessment of Insulin Resistance indicated a resistance condition to insulin (p<0.05) in the scoliosis group (0.66±0.03), when compared to the control group (0.81±0.02). CONCLUSIONS: The scoliosis curvature remained stable 30 days after immobilization. The chemical and metabolic analyses suggest changes in muscular homeostasis during the induced scoliosis process.
CONTEXTUALIZAÇÃO: Encontram-se na literatura diversos modelos experimentais de indução de escoliose em ratos, porém evidencia-se o uso de drogas ou intervenções invasivas para a geração da curvatura escoliótica. OBJETIVOS: Projetar e aplicar um modelo de imobilização não-invasiva para a indução de escoliose em ratos. MÉTODOS: Ratos Wistar machos com idade inicial de quatro semanas (85±3,3g) foram divididos nos grupos controle (GC) e escoliose (GE). Os animais do GE foram imobilizados por dois cintos (escapular e pélvico) de policloreto de vinila (PVC), interligados externamente por um limitador que regulava o ângulo da escoliose durante 12 semanas, com convexidade à esquerda. Após a imobilização, os músculos abdominais, intercostais, paravertebrais e peitorais bilateralmente foram coletados para as análises químio-metabólicas. Os registros radiológicos foram realizados a cada 30 dias, num total de 16 semanas. RESULTADOS: O modelo foi eficiente e eficaz na indução da escoliose, mesmo após 30 dias da desmobilização, mantendo um ângulo estável de 28±5 graus. Quanto às análises químio-metabólicas, observou-se diminuição (p<0,05) nas reservas glicogênicas e na relação proteína total/DNA de todos os músculos analisados do GE, sendo menores (p<0,05) no lado da convexidade. Os valores do HOMA-IR indicaram um quadro de resistência à insulina (p<0,05) no GE (0,66±0,03) quando comparado ao GC (0,81±0,02). CONCLUSÕES: A curvatura escoliótica manteve-se estável após 30 dias da desmobilização, e as alterações químio-metabólicas sugeriram a ocorrência de modificações na homeostasia muscular durante o processo indutor da escoliose.
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Animais , Masculino , Ratos , Modelos Animais de Doenças , Imobilização/métodos , Escoliose , Desenho de Equipamento , Imobilização/instrumentação , Ratos WistarRESUMO
BACKGROUND: In the literature, there are several experimental models that induce scoliosis in rats; however, they make use of drugs or invasive interventions to generate a scoliotic curve. OBJECTIVES: To design and apply a non-invasive immobilization model to induce scoliosis in rats. METHODS: Four-week old male Wistar rats (85±3.3g) were divided into two groups: control (CG) and scoliosis (SG). The animals in the SG were immobilized by two vests (scapular and pelvic) made from polyvinyl chloride (PVC) and externally attached to each other by a retainer that regulated the scoliosis angle for twelve weeks with left convexity. After immobilization, the abdominal, intercostal, paravertebral, and pectoral muscles were collected for chemical and metabolic analyses. Radiographic reports were performed every 30 days over a 16-week period. RESULTS: The model was effective in the induction of scoliosis, even 30 days after immobilization, with a stable angle of 28±5º. The chemical and metabolic analyses showed a decrease (p<0.05) in the glycogenic reserves and in the relationship between DNA and total protein reserves of all the muscles analyzed in the scoliosis group, being lower (p<0.05) in the convex side. The values for the Homeostatic Model Assessment of Insulin Resistance indicated a resistance condition to insulin (p<0.05) in the scoliosis group (0.66±0.03), when compared to the control group (0.81±0.02). CONCLUSIONS: The scoliosis curvature remained stable 30 days after immobilization. The chemical and metabolic analyses suggest changes in muscular homeostasis during the induced scoliosis process.
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Modelos Animais de Doenças , Imobilização/métodos , Escoliose , Animais , Desenho de Equipamento , Imobilização/instrumentação , Masculino , Ratos , Ratos WistarRESUMO
BACKGROUND: The reduction of the pelvic floor muscles (PFM) strength is a major cause of stress urinary incontinence (SUI). OBJECTIVES: To compare active and passive forces, and vaginal cavity aperture in continent and stress urinary incontinent women. METHOD: The study included a total of thirty-two women, sixteen continent women (group 1--G1) and sixteen women with SUI (group 2--G2). To evaluate PFM passive and active forces in anteroposterior (sagittal plane) and left-right directions (frontal plane) a stainless steel specular dynamometer was used. RESULTS: The anteroposterior active strength for the continent women (mean±standard deviation) (0.3±0.2 N) was greater compared to the values found in the evaluation of incontinent women (0.1±0.1 N). The left-right active strength (G1=0.43±0.1 N; G2=0.40±0.1 N), the passive force (G1=1.1±0.2 N; G2=1.1±0.3 N) and the vaginal cavity aperture (G1=21±3 mm; G2=24±4 mm) did not differ between groups 1 and 2. CONCLUSION: The function evaluation of PFM showed that women with SUI had a lower anteroposterior active strength compared to continent women.
Assuntos
Diafragma da Pelve/fisiopatologia , Incontinência Urinária por Estresse/fisiopatologia , Adulto , Feminino , Humanos , Diafragma da Pelve/fisiologiaRESUMO
OBJETIVO: Avaliar a resistência elétrica inicial e no decorrer do tempo de agentes de acoplamento utilizados na interface eletrodo-pele submetidos a estimulação elétrica com corrente bifásica e corrente contínua. MÉTODOS: A resistência elétrica foi calculada indiretamente pela Lei de Ohm, sendo a tensão elétrica gerada em um equipamento de corrente constante (10 mA, 100 Hz, 100 μs e pulso bifásico quadrado simétrico) e captada por um osciloscópio digital. Dez agentes de acoplamento (géis, n=5; líquidos, n=5) foram submetidos à eletrólise com corrente bifásica quadrática simétrica (CB), 0,0134 mA/mm², 100 Hz, 100 μs ou com corrente contínua (CC) a 0,0017 mA/mm² de densidade de corrente, durante 30 minutos, sendo reavaliados a cada 5 minutos. Para análise dos dados, aplicaram os testes de Friedman e Kruskal-Wallis, seguidos de Rank e Dunn, respectivamente, e, para a correlação, empregou-se o coeficiente de Spearman (α=0,05). RESULTADOS: Os valores iniciais de resistência dos géis variaram entre 116,00 e 146,00 Ω, e dos agentes de acoplamento líquidos, entre 106,00 e 4726,67 Ω, apresentando, em sua maioria, correlação positiva com o tempo de eletrólise. Conclusões: Conclui-se que os géis, a água potável e a solução fisiológica são os indicados para a prática da estimulação elétrica terapêutica, pois mantêm a baixa resistência durante o período de estimulação. Por outro lado, o uso de água destilada ou desionizada não é recomendado, pois apresentam alta resistência à passagem da corrente.
OBJECTIVE: To evaluate the initial and ongoing electrical resistance of different coupling agents used in the skin-electrode interface. The agents were submitted to electrical stimulation with biphasic and direct currents. METHODS: The electrical resistance was calculated indirectly by Ohm's Law. The tension was generated by a constant current generator (10 mA, 100 Hz, 100 µs and symmetrical biphasic square pulse) and captured by a digital oscilloscope. Ten coupling agents (gels, n=5; liquids, n=5) were submitted to electrolysis with symmetrical biphasic square current (BC), 0.0134 mA/mm², 100 Hz, 100 µs or with direct current (DC) at 0.0017 mA/mm² for 30 minutes, being reassessed every 5 minutes. For data analysis the Friedman and Kruskal-Wallis tests were applied, followed by the rank test and the Dunn test respectively. Also, Spearman's coefficient test was used for correlation analysis (α=0.05). RESULTS: The initial resistance values of the gels varied between 116.00 and 146.00 Ω and of the liquid coupling agents, between 106.00 and 4726.67 Ω, with mostly positive correlation with the time of electrolysis. CONCLUSIONS: We concluded that gels, drinking water and saline solution are recommended for the practice of therapeutic electrical stimulation because they maintain low resistance during stimulation. In contrast, the use of distilled or deionized water is not recommended due to the high resistance to the passage of electrical current.
RESUMO
Thirty-three (33) healthy volunteers (2.29 +/- 2.4 years) participated. Two active surface electrodes were placed on the rectus femoris muscle: one on the motor point (M) and the other on the thickest distal portion of the muscle (V). The volunteer was positioned on a Bonet table, with his/her trunk fixed, thigh at 90 degrees and leg with 105 degrees and 45 degrees flexion. The signal was collected simultaneously in the 2 electrodes and in the load cell, during the extension of the leg at 50% or 100% of the maximum voluntary isometric contraction (MVIC) for 5 seconds, repeated 3 times, with an interval of 1 minute. The EMG signal was obtained through a data acquisition module (EMG1000 - Lynx) of 16 bits (LYNX), with band- pass filter of 20-1.000 Hz and sampling frequency of 2.000 Hz. RMS and mean frequency (MF) were assessed with Matlab software. Statistical analysis consisted of the Wilcoxon test and Student t test (p < 0.05). At 50% of the MVIC, the RMS was greater in the shortened muscle than the lengthened one. Whereas at 100% there was an inversion, with the lengthened muscle presenting greater amplitude. The FM both at 50% and 100% MVIC was greater for the muscle in the shortened position. It was possible to conclude that changes in muscular length and in contraction intensity alter the electromyographic variables.
Assuntos
Eletromiografia , Contração Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Potenciais de Ação/fisiologia , Adulto , Interpretação Estatística de Dados , Feminino , Humanos , Contração Isométrica/fisiologia , MasculinoRESUMO
O cancer de mama é uma das principais causas de mortalidade entre mulheres. Ocupa o primeiro lugar entre os canceres em numero de intervençoes cirurgicas, acarretando varias alteraçoes, dentre elas a fraqueza muscular e limitaçao da amplitude de movimento (ADM) homolateral á cirurgia. O estudo teve como objetivo verificar a atividade e força dos musculo deltoide medio (DM) e trapezio superior (TS), bem como a ADM de mulheres submetidas a mastectomia radical modificada recente e tardia, apos treinamento utilizando a Facilitacao Neuromuscular Proprioceptiva (PNF), 2 vezes semanais, por 8 semanas. Foram selecionadas 12 voluntarias entre 40 e 70 anos (56,2 + ou - 11,8), separadas em grupo: 1- mastectomia radical modificada recente(até 2 anos de cirurgia); 2- mastectomia radical modificada tardia (acima de 2 anos). Os dados eletromiograficos colhidos pre e pos-intervençao, foram analisados atraves do teste de normalidade KSL para força e envoltoria nao normalizada(ENN). A analise tambem constou da goniometria pre e pos-intervençao. Os resultados demosntram aumento significativo(p<0,0001) na ativaçao e força dos musculos analisados, bem como aumento na ADM(p<0,02), sendo mais evidente no grupo recente. Conclui-se que o protocolo proposto foi eficaz priciplamente no grupo 1, onde a intervençao ocorreu mais precocimente.