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1.
J Sports Sci ; 38(4): 430-469, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31889469

RESUMO

High-intensity-interval-training (HIIT) has been suggested to have beneficial effects in multiple populations across individual systematic reviews, although there is a lack of clarity in the totality of the evidence whether HIIT is effective and safe across different populations and outcomes. The aim of this meta-review was to establish the benefits, safety and adherence of HIIT interventions across all populations from systematic reviews and meta-analyses. Major databases were searched for systematic reviews (with/without meta-analyses) of randomised & non-randomised trials that compared HIIT to a control. Thirty-three systematic reviews (including 25 meta-analyses) were retrieved encompassing healthy subjects and people with physical health complications. Evidence suggested HIIT improved cardiorespiratory fitness, anthropometric measures, blood glucose and glycaemic control, arterial compliance and vascular function, cardiac function, heart rate, some inflammatory markers, exercise capacity and muscle mass, versus non-active controls. Compared to active controls, HIIT improved cardiorespiratory fitness, some inflammatory markers and muscle structure. Improvements in anxiety and depression were seen compared to pre-training. Additionally, no acute injuries were reported, and mean adherence rates surpassed 80% in most systematic reviews. Thus, HIIT is associated with multiple benefits. Further large-scale high-quality studies are needed to reaffirm and expand these findings.Abbreviations: ACSM: American College of Sports Medicine; BMI: Body Mass Index; BNP: Brain Natriuretic Peptide; BP: Blood Pressure; CAD: Coronary Artery Disease; CHD: Coronary Heart Disease; COPD: Chronic Obstructive Pulmonary Disease; CRP: c- reactive Protein; CVD: Cardiovascular Disease; DBP: Diastolic Blood Pressure; ES: Effect Size; FAS: Reduced Fatty Acid Synthase; FATP-1: Reduced Fatty Acid Transport Protein 1; FMD: Flow Mediated Dilation; Hs-CRP: High-sensitivity c- reactive Protein; HDL: High Density Lipoprotein; HIIT: High-Intensity Interval Training; HOMA: Homoeostatic Model Assessment; HR: Heart Rate; HTx: Heart Transplant Recipients; IL-6: Interleukin-6; LDL: Low Density Lipoprotein; LV: Left Ventricular; LVEF: Left Ventricular Ejection Fraction; MD: Mean Difference; MetS: Metabolic Syndrome; MPO: Myeloperoxidase; MICT: Moderate-Intensity Continuous Training; NO: Nitric Oxide; NRCT: Non-Randomised Controlled Trial; PA: Physical Activity; PAI-1: Plasminogen-activator-inhibitor-1; QoL: Quality of Life; RCT: Randomised Controlled Trial; RoB: Risk of Bias; RPP: Rate Pressure Product; RT: Resistance Training; SBP: Systolic Blood Pressure; SD: Standardised Difference; SMD: Standardised Mean Difference; TAU: Treatment-As-Usual; T2DM: Type 2 Diabetes Mellitus; TC: Total Cholesterol; TG: Triglycerides; TNF-alfa: Tumour Necrosis Factor alpha; UMD: Unstandardised Mean Difference; WC: Waist Circumference; WHR: Waist-to-Hip Ratio; WMD: Weighted Mean DifferenceKey points: HIIT may improve cardiorespiratory fitness, cardiovascular function, anthropometric variables, exercise capacity, muscular structure and function, and anxiety and depression severity in healthy individuals and those with physical health disorders.Additionally, HIIT appears to be safe and does not seem to be associated with acute injuries or serious cardiovascular events.


Assuntos
Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade/psicologia , Saúde Mental , Qualidade de Vida , Antropometria , Ansiedade/prevenção & controle , Biomarcadores/sangue , Depressão/prevenção & controle , Tolerância ao Exercício , Humanos , Inflamação/sangue , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia
2.
Int J Vitam Nutr Res ; 90(1-2): 113-123, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30545278

RESUMO

ß-hydroxy-ß-methyl butyrate (HMB) is a bioactive metabolite derived from the amino acid leucine, usually applied for muscle mass increase during physical training, as well as for muscle mass maintenance in debilitating chronic diseases. The hypothesis of the present study is that HMB is a safe supplement for muscle mass gain by strength training. Based on this, the objective was to measure changes in body composition, glucose homeostasis and hepatic metabolism of HMB supplemented mice during strength training. Two of four groups of male mice (n = 6/group) underwent an 8-week training period session (climbing stairs) with or without HMB supplementation (190 mg/kgBW per day). We observed lower body mass gain (4.9 ± 0.43% versus 1.2 ± 0.43, p < 0.001) and increased liver mass (40.9 ± 0.9 mg/gBW versus 44.8 ± 1.3, p < 0.001) in the supplemented trained group compared with the non-supplemented groups. The supplemented trained group had an increase in relative adipose tissue mass (12.4 ± 0.63 mg/gBW versus 16.1 ± 0.88, P < 0.01) compared to the non-supplemented untrained group, and an increase in fasting blood glucose (111 ± 4.58 mg/dL versus 122 ± 3.70, P < 0.05) and insulin resistance (3.79 ± 0.19 % glucose decay/min versus 2.45 ± 0.28, P < 0.05) comparing with non-supplemented trained group. Adaptive heart hypertrophy was observed only in the non-supplemented trained group (4.82 ± 0.05 mg/gBW versus 5.12 ± 0.13, P < 0.05). There was a higher hepatic insulin-like growth factor-1 expression (P = 0.002) in supplemented untrained comparing with non-supplemented untrained group. Gene expression of gluconeogenesis regulatory factors was increased by training and reduced by HMB supplementation. These results confirm that HMB supplementation associated with intensive training protocol drives changes in glucose homeostasis and liver metabolism in mice.


Assuntos
Suplementos Nutricionais , Glucose/metabolismo , Homeostase/efeitos dos fármacos , Músculo Esquelético , Valeratos/metabolismo , Animais , Glucose/química , Humanos , Fígado , Masculino , Camundongos , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Valeratos/química
3.
Arch Gerontol Geriatr ; 86: 103942, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31542632

RESUMO

BACKGROUND/OBJECTIVES: Calf circumference (CC) is an indirect method used to evaluate muscle mass in older adults. Ultrasound has also been studied as a method for measuring muscle mass. Therefore, the aim of the present study was to correlate CC and muscle thickness of the medial gastrocnemius muscle (MGM) in healthy older women. METHODS: A cross-sectional study was conducted with 74 healthy older women. The MGM thickness was evaluated using an ultrasound device (Logiq Book XP, General Electric®). The reference value for adequate CC was ≥ 31 cm. Weight and height were measured for the calculation of the body mass index (BMI), which was dichotomized as with or without excess weight based on the cutoff points recommended by the World Health Organization (1995); Lipschitz (1994) and the Pan-American Health Organization (2001). RESULTS: All participants were ≥ 64 years of age. Mean weight and height were 66.19 kg (SD: 10.48) and 1.55 m (SD: 0.06), respectively. Half of the participants had a BMI higher than 27.53 kg/m2. Moderate positive correlations were found between CC and MGM thickness (ρ = 0.432; p < 0.001), MGM thickness and weight (r = 0.422; p < 0.001) and between MGM thickness and BMI (r = 0.438; p < 0.001). However, the correlation between CC and MGM thickness was non-significant among the women with excess weight. CONCLUSIONS: A moderate positive correlation between MGM thickness and CC was found in healthy older women. However, this correlation was weak and non-significant among those with excess weight.


Assuntos
Antropometria/métodos , Perna (Membro)/anatomia & histologia , Força Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos Transversais , Feminino , Fragilidade , Voluntários Saudáveis , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Valores de Referência , Pregas Cutâneas , Saúde da Mulher
4.
J Sports Sci Med ; 18(4): 722-728, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31827357

RESUMO

The purpose of the present study was to investigate the effect of the progressive walking program on lower limb muscle size and strength and evaluated whether the stair-climbing exercise provided additional training effects when combined with the walking program. Fifteen elderly subjects (age 69 ± 1 years, height 1.63 ± 0.02 m, body weight 64.5 ± 2.0 kg) were randomly assigned to a walking group or a walking and stair-climbing group. The progressive walking program comprised continuous (week 1-8) and interval (week 9-17) exercises. The walking and stair-climbing group also performed stair climbing. Muscle thickness, strength, and walking performance were evaluated before and 8 and 17 weeks after the start of the program. The muscle thickness of the anterior and posterior parts of the thigh significantly (p < 0.05) increased in both groups. There was also a significant (p < 0.01) main effect of time in isometric maximal strength and the values expressed relative to body mass for both knee extension and flexion. However, no group × time interactions were noted. Furthermore, the percentage change of knee flexion strength after the training period was significantly (p < 0.01) correlated with the pre-intervention value. Seventeen weeks of the progressive walking program can increase thigh muscle size and strength for older adults; however, an added stair-climbing exercise may not provide additional training effects. Furthermore, the magnitude of improvement in knee flexion strength would depend on the pre-intervention value.


Assuntos
Extremidade Inferior/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Condicionamento Físico Humano/métodos , Subida de Escada/fisiologia , Caminhada/fisiologia , Idoso , Feminino , Humanos , Joelho/fisiologia , Masculino , Coxa da Perna
5.
J Sports Sci Med ; 18(4): 751-757, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31827360

RESUMO

This study aimed to examine longitudinal age-related changes in muscle morphology and jump and sprint performances of youth athletes. The subjects of this longitudinal study were 41 youth male basketball players who were assigned to late, mid, and early groups based on differences regarding the estimated age at peak height velocity. The vastus medialis, vastus intermedius, rectus femoris, vastus lateralis, biceps brachii, and triceps brachii thicknesses were assessed using ultrasonography. The subjects' anaerobic capacities were evaluated based on Abalakov jumps and 20-m sprint time. After 1 year, the vastus medialis and biceps brachii thicknesses increased significantly in all groups, and the rectus femoris, vastus intermedius, and vastus lateralis thicknesses increased significantly in the late and mid groups, but not in the early group. The Abalakov jumps and 20-m sprint time improved significantly in all groups. The early group's 10-m sprint time improved significantly. Cross-sectional comparisons showed that after 1 year, the early group's Abalakov jumps and 20-m sprint time at baseline, its Abalakov jumps, and 10-m and 20-m sprint times were significantly better than those in the mid and late groups. Hence, significant muscle growth occurred before the athletes reached the age at peak height velocity. During puberty, late maturers' sprint times and jump performances may not catch up with those of early maturers. The speed and tempo of the morphological growth and anaerobic ability of athletes in the same age category depend on athletes' biological maturity.


Assuntos
Desempenho Atlético/fisiologia , Basquetebol/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/crescimento & desenvolvimento , Puberdade/fisiologia , Adolescente , Fatores Etários , Estatura/fisiologia , Criança , Teste de Esforço , Humanos , Estudos Longitudinais , Masculino , Músculo Esquelético/diagnóstico por imagem , Ultrassonografia
6.
J Sports Sci Med ; 18(4): 772-779, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31827362

RESUMO

A common practice among bodybuilders is the use of carbohydrate loading to improve physical appearance during competition, while limited documented data is available about this issue. The aim of the present study was to evaluate muscle thickness, mood states, gastrointestinal symptoms and subjective silhouette assessment following carbohydrate loading in bodybuilders. Twenty-four male bodybuilders were evaluated at the weighing period following three days of carbohydrate depletion (M1), and 24h of carbohydrate loading leading up to the competition (M2), stratified into: no carbohydrate load (NC, n = 9) and carbohydrate loading (CL, n =1 5). The silhouette scale, Brunel mood scale (BRUMS), muscle thickness (ultrasound), circumferences, and gastrointestinal symptoms (GIS) were evaluated at M1 and M2. The NC displayed no differences in muscle thickness and circumferences between M1 and M2. Body mass, muscle thickness (elbow flexors, a combination of biceps brachii/ brachialis muscle, and triceps brachii) and circumferences (chest, hip, thigh, arm, calves, and forearm) increased significantly (p < 0.05) in the CL at M2. There was a significant increase in photo silhouette scores (p < 0.05) in the CL at M2. There was no significant difference in mood states between groups or time. The most reported GIS was constipation: 7/9 (NC) and 9/15 (CL) during M1 and 6/9 (NC), and 5/15 (CL) at M2 with symptoms described as 'moderate' or 'severe'. Diarrhea was reported by 7/15 CL (4/15 as severe). These data suggest that carbohydrate loading may contribute to an acute increase in muscle volume and physical appearance, however, it needs to be better planned to minimize gastrointestinal symptoms in bodybuilders.


Assuntos
Afeto , Constipação Intestinal/etiologia , Diarreia/etiologia , Dieta da Carga de Carboidratos/efeitos adversos , Músculo Esquelético/anatomia & histologia , Levantamento de Peso/fisiologia , Levantamento de Peso/psicologia , Adulto , Índice de Massa Corporal , Comportamento Competitivo/fisiologia , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagem , Fotografação , Ultrassonografia , Adulto Jovem
7.
Int. j. morphol ; 37(4): 1286-1293, Dec. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1040126

RESUMO

Profile and standards for the diagnostics of percent of body fat and muscles were defined on a sample of 1924 women from the Republic of Serbia, aged 18.0 to 69.9, where the body structure of subjects was measured by applying multichannel segmental bioimpedance. Total sample was divided into six age groups, for the purpose of the definition of standard with regards to age. When it comes to body fat percentage results have shown that the average value of the total sample was 28.51±9.26 %, and between the range of 23.81 and 39.94 % for age groups 18.0-19.9 yr and 60.0-69.9 yr, respectively. Regression analysis results have shown that the constant of body fat percentage increase by trend of 3.417 % per decade, and that 25.1 % of mutual variance trend was explained by the model, with prediction error of 4.55 %. With regards to the percentage of skeletal muscles in the body, the results have shown that the average value of the total sample was 39.30±5.25 %, and within the range of 42.25 to 32.58 % for age groups 18.0-19.9 yr and 60.0-69.9 yr, respectively. Regression analysis results have shown that the constant of the skeletal muscles decrease by tend of -2.016 % per decade and that the model explained 23.8 % of mutual variance trend with prediction error of 8.08 %.


El perfil y estándares para el diagnóstico del porcentaje de grasa corporal y masa muscular fueron definidos en una muestra de 1924 mujeres de la República de Serbia, con edades comprendidas entre 18,0 y 69,9 años, donde la composición corporal de los sujetos fue medida por bioimpedancia segmentaria multicanal. La muestra fue dividida en seis grupos, con el propósito de definir los estándares respecto a la edad. Respecto al porcentaje de grasa corporal los resultados han mostrado que el valor promedio de la muestra fue de 28,51±9,26 %, y entre los rangos de 23,81 y 39,94 para los grupos de edad de 18,0-19,9 años y 60,069,9 años, respectivamente. Los resultados del análisis de regresión mostraron que la constante del porcentaje de grasa corporal aumentó 3,417 % por década, y que un 25,1 % de la varianza fue explicada por el modelo, con un error de predicción de 4,55 %. Con respecto al porcentaje de masa muscular, los resultados han mostrado que el valor promedio de la muestra fue de 39,30±5,25 %, y entre los rangos de 42,24 y 32,58 para los grupos de edad de 18,0-19,9 años y 60,0-69,9 años, respectivamente. Los resultados del análisis de regresión han mostrado que la constante de masa muscular decreció -2,016 % por década y que el modelo explicó 23,8 % de la varianza con un error de predicción de 8,08 %.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Composição Corporal , Tecido Adiposo/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Valores de Referência , Estudos Transversais , Inquéritos e Questionários , Análise de Regressão , Análise de Variância , Impedância Elétrica , Distribuição por Idade , Sérvia
8.
Int. j. morphol ; 37(4): 1361-1369, Dec. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1040138

RESUMO

In elite athletes, the palmaris longus (PL) presence has a potential contribution to hand strength, smaller reaction time, better shooting speed and power. The aim of this study was to investigate the prevalence of PL in elite competitive artistic gymnasts and its impact on grip strength compared to a control group of moderately active non-athletes. This prospective study included 370 subjects divided in two groups (170 elite artistic gymnasts and 200 moderately active non-athletes, students of medicine). The study consisted of two clinical sets of examination: a search for the clinical presence of PL was initially conducted followed by the assessment of maximal grip strength. Standard and six additional tests were performed to confirm PL tendon absence. Maximal grip strength was measured bilaterally with an electronic hand dynamometer. Bilateral absence was more common than unilateral, predominately noted on left side in both study groups. Unilateral PL absence was correlated to decreased grip strength in students, while the opposite was found in gymnasts. The mean value of grip strength in some age groups was higher on the side where the PL was absent. The results of our study show that the presence of the PL doesn`t affect the hand grip strength in gymnasts. Due to the low incidence of unilateral PL absence, further large-sampled research is warranted to assess PL contribution to hand grip strength and to other hand functions that could be of significant importance for athletes and non-athletes.


La presencia del músculo palmar largo (MPL) en atletas de élite tiene el potencial de aportar mayor fuerza a la mano, un tiempo de reacción menor, mejor velocidad de tiro y potencia. El objetivo de este estudio fue investigar la prevalencia de MPL en las gimnastas artísticas competitivas de élite y su impacto en la fuerza de agarre en comparación con un grupo control de no atletas moderadamente activos. El estudio incluyó 370 sujetos divididos en dos grupos (170 gimnastas artísticas de élite y 200 no atletas moderadamente activos, estudiantes de medicina). El estudio consistió en dos series clínicas de examen: inicialmente se realizó una búsqueda de la presencia clínica de MPL, seguido de la evaluación de la fuerza máxima de agarre. Se realizaron pruebas estándar y seis pruebas adicionales para confirmar la ausencia del tendón del MPL. La máxima fuerza de agarre se midió bilateralmente con un dinamómetro de mano electrónico. La ausencia bilateral fue más común que unilateral, predominantemente observada en el lado izquierdo en ambos grupos de estudio. La ausencia unilateral de MPL se correlacionó con una menor fuerza de agarre en los estudiantes, mientras que en gimnastas se encontró lo contrario. El valor medio de la fuerza de agarre en algunos grupos de edad fue mayor en el lado donde el MPL estaba ausente. Los resultados de nuestro estudio muestran que la presencia de MPL no afecta la fuerza de agarre de la mano en gimnastas. Debido a la baja incidencia de ausencia unilateral de MPL, se justifica una investigación adicional de gran tamaño para evaluar la contribución de MPL a la fuerza de agarre de la mano y otras funciones de la mano que podrían ser de gran importancia para los atletas y no atletas.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Músculo Esquelético/anatomia & histologia , Força da Mão/fisiologia , Atletas , Ginástica , Prevalência , Análise Multivariada , Estudos Prospectivos , Fatores Etários
9.
PLoS Comput Biol ; 15(9): e1006883, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31487282

RESUMO

How muscles are used is a key to understanding the internal driving of fish swimming. However, the underlying mechanisms of some features of the muscle activation patterns and their differential appearance in different species are still obscure. In this study, we explain the muscle activation patterns by using 3D computational fluid dynamics models coupled to the motion of fish with prescribed deformation and examining the torque and power required along the fish body with two primary swimming modes. We find that the torque required by the hydrodynamic forces and body inertia exhibits a wave pattern that travels faster than the curvature wave in both anguilliform and carangiform swimmers, which can explain the traveling wave speeds of the muscle activations. Notably, intermittent negative power (i.e., power delivered by the fluid to the body) on the posterior part, along with a timely transfer of torque and energy by tendons, explains the decrease in the duration of muscle activation towards the tail. The torque contribution from the body elasticity further clarifies the wave speed increase or the reverse of the wave direction of the muscle activation on the posterior part of a carangiform swimmer. For anguilliform swimmers, the absence of the aforementioned changes in the muscle activation on the posterior part is consistent with our torque prediction and the absence of long tendons from experimental observations. These results provide novel insights into the functions of muscles and tendons as an integral part of the internal driving system, especially from an energy perspective, and they highlight the differences in the internal driving systems between the two primary swimming modes.


Assuntos
Peixes , Modelos Biológicos , Músculo Esquelético , Natação/fisiologia , Animais , Fenômenos Biomecânicos/fisiologia , Biologia Computacional , Simulação por Computador , Peixes/anatomia & histologia , Peixes/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Fenômenos Fisiológicos Musculoesqueléticos
10.
Foot Ankle Clin ; 24(3): 371-385, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31370991

RESUMO

The pathologic conditions of the Achilles tendon are best understood in the context of its unique anatomy and functional demands. Some of these unique considerations include its high physiologic load demands, microscopic tissue composition, muscular origin spanning the knee joint, intimate insertional relationship with the plantar fascia, sensory innervation, and vascular supply with watershed areas. Risks of both acute rupture and chronic tendinopathy are affected by the tendon's anatomy and its functional demands. The tendon's functional anatomy changes with advancing age, notably in its collagen composition and vascular supply.


Assuntos
Tendão do Calcâneo/anatomia & histologia , Tendão do Calcâneo/fisiologia , Tendinopatia/fisiopatologia , Traumatismos dos Tendões/fisiopatologia , Tendão do Calcâneo/lesões , Humanos , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Ruptura
11.
Zoology (Jena) ; 135: 125678, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31383297

RESUMO

In a majority of ray-finned fishes (Actinopterygii), effective acquisition of food resources is predicated on rapid jaw adduction. Although the musculoskeletal architecture of the feeding system has been the subject of comparative research for many decades, individual contributions of the major adductor divisions to closing dynamics have not been elucidated. While it is understood that the dorsal divisions that arise from the head and insert on the posterior of the lower jaw are major contributors to closing dynamics, the contribution of the ventral components of the adductor system has been largely overlooked. In many ray-finned fishes, the ventral component is comprised of a single division, the Aω, that originates on an intersegmental aponeurosis of the facialis divisions and inserts on the medial face of the dentary, anterior to the Meckelian tendon. This configuration resembles a sling applied at two offset points of attachment on a third-order lever. The goal of this study was to elucidate the contributions of the Aω to jaw adduction by modeling jaw closing in the deep-sea viperfish Chauliodus sloani. To do this, we simulated adduction with a revised computational model that incorporates the geometry of the Aω. By comparing results between simulations that included and excluded Aω input, we show that the Aω adds substantially to lower-jaw adduction dynamics in C. sloani by acting as a steering motor and displacing the line of action of the dorsal facialis adductor muscles and increasing the mechanical advantage and input moment arms of the jaw lever system. We also explored the effect of the Aω on muscle dynamics and found that overall facialis muscle shortening velocities are higher and normalized force production is lower in simulations including the Aω. The net effect of these changes in muscle dynamics results in similar magnitudes of peak power in the facialis divisions between simulations, however, peak power is achieved earlier in adduction Modifications of muscle mechanics and posture result in significant increases in closing performance, including static bite force, angular velocity, and adduction time. We compare this configuration to a similar design in crocodilians and suggest that the Aω configuration and similar sling configurations across the vertebrate tree of life indicate the importance of this musculoskeletal design in feeding.


Assuntos
Simulação por Computador , Peixes/fisiologia , Músculo Esquelético/fisiologia , Animais , Comportamento Alimentar/fisiologia , Peixes/anatomia & histologia , Arcada Osseodentária/anatomia & histologia , Músculo Esquelético/anatomia & histologia
12.
Muscle Nerve ; 60(5): 582-585, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31443126

RESUMO

INTRODUCTION: Our aim in this work was to determine the safety and accuracy of the volar approach to the pronator quadratus (PQ) through cadaver dissection. METHODS: Twenty upper limbs from 10 fresh cadavers were investigated. At the level 3 cm proximal to the ulnar styloid process (USP), a needle was inserted just medial to the palmaris longus (PL) tendon. Distances of the median nerve (MN) and ulnar artery (UA) from the needle insertion point (IP) were measured using ultrasonography and cadaver dissection. RESULTS: The PQ was located at a depth of 10.8-19.9 mm from the skin and had a median thickness of 9.1 mm, measured 3 cm proximal to the USP. The median distances of the MN and UA from the IP were 7.6 and 13.4 mm, respectively. DISCUSSION: A needle insertion for the volar approach to the PQ was safe at 3 cm proximal to the USP, just medial to the PL tendon.


Assuntos
Pontos de Referência Anatômicos , Antebraço/anatomia & histologia , Nervo Mediano/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Artéria Ulnar/anatomia & histologia , Cadáver , Dissecação , Eletromiografia/métodos , Feminino , Antebraço/diagnóstico por imagem , Humanos , Masculino , Nervo Mediano/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Tendões , Artéria Ulnar/diagnóstico por imagem , Ultrassonografia
13.
Yonsei Med J ; 60(9): 876-881, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31433586

RESUMO

Architectural changes in healthy muscle after denervation have not yet been reported. This study aimed to investigate architectural changes in the medial head of the gastrocnemius muscle (GCM) after aesthetic tibial nerve ablation in healthy adults using ultrasonography (US). The effects of tibial nerve ablation were verified by visual observation and surface electromyography analysis. US images of medial GCMs were taken by one trained physician using B-mode and real-time US with a linear-array probe before nerve ablation, at 1 week after nerve ablation and at 3 months after nerve ablation in an anatomic standing position with the feet about shoulder-width apart in 19 healthy adults (17 females and 2 males). Muscle thickness was significantly reduced on the left side at 1 week and 3 months after the procedure and on the right side at 3 months after the procedure (p<0.050). Although fascicle length was not significantly changed, pennation angle was significantly reduced on both sides at 3 months after the procedure (p<0.050). Muscle thickness and pennation angle of the muscle fascicle were significantly reduced, although fascicle length was not significantly changed, after tibial nerve ablation in the medial GCM of healthy adults.


Assuntos
Denervação Muscular/efeitos adversos , Músculo Esquelético/anatomia & histologia , Nervo Tibial/cirurgia , Adulto , Eletromiografia , Feminino , Humanos , Terapia a Laser , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Estudos Prospectivos , Ultrassonografia
14.
BMC Med Imaging ; 19(1): 69, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31426754

RESUMO

BACKGROUND: Pocket-sized ultrasound devices are increasingly used in a variety of clinical situations, and perform well against standard ultrasound machines. We sought to investigate if a pocket-sized ultrasound device can assess muscle thickness and architecture in healthy volunteers. METHODS: Healthy male volunteers (n = 21) across a range of ages were recruited to the study. Laying supine, ultrasound images were taken from the right anterior and lateral thigh. Thickness of the rectus femoris (RFMT), vastus intermedius (VIMT), and the two combined (anterior thigh, AMT) were measured, along with thickness of vastus lateralis (VLMT), pennation angle (VLPA) and derived fascicle length (VLFL). These scans were performed initially using a pocket-sized ultrasound (VScan) and then using a standard device (Telemed Echoblaster 128). RESULTS: In all six variables, there was no significant difference between the two sets of measurements. Intra-class correlation co-efficients (ICC) for VLMT, VLPA, and AMT were all excellent (0.93, 0.89, 0.90 respectively) with the derived value of VLFL having an ICC of 0.84. All ICC values were statistically significant. Regression analysis demonstrated no evidence of proportional bias in any of the measured or derived variables. CONCLUSION: A pocket-sized ultrasound device gives similar measurements of lower limb muscle thickness and architecture as a standard device in healthy volunteers.


Assuntos
Músculo Esquelético/diagnóstico por imagem , Coxa da Perna/diagnóstico por imagem , Ultrassonografia/instrumentação , Adulto , Idoso , Equipamentos e Provisões , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/anatomia & histologia , Interpretação de Imagem Radiográfica Assistida por Computador , Decúbito Dorsal , Coxa da Perna/anatomia & histologia , Adulto Jovem
15.
J Sports Sci Med ; 18(3): 454-461, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31427867

RESUMO

Higher stiffness of the Achilles tendon (AT) and gastrocnemius have been found to be risk factors associated with Achilles tendinitis. Static stretching (SS) is one intervention that has been investigated to improve the flexibility and therefore reduce injury risk. Previous studies have investigated the acute effect of SS on one region for AT and gastrocnemius morphology and stiffness; however, there is a lack of knowledge about the effect of SS on other regions of the AT and gastrocnemius (e.g., proximal vs. distal, within gastrocnemius). The aims of the present study were: (1) to investigate the acute effects of SS on the shear modulus of the medial gastrocnemius muscles (MG) and lateral gastrocnemius muscles (LG) and AT for different regions; (2) to examine the differences in range of motion (ROM) before and after SS; and (3) to investigate the change of thickness of AT and fascicle length of MG and LG before and after SS. The stiffness of AT and the gastrocnemius, fascicle length of the muscles, thickness of the AT, and maximal ankle joint dorsiflexion angle were measured in thirty healthy subjects (15 males, 15 females) before(pre) and immediately after (post) 5-minute SS. Stretching effects are not homogeneous among different regions. After SS administration, the proximal, middle, and distal regions of MG stiffness decreased by 34.12%, 22.45%, and 25.27%, respectively (p = 0.000), and LG stiffness decreased by 37.71%, 30.47%, and 22.13%, respectively (p = 0.000), whereas AT stiffness increased by 25.73%, 17.01%, and 19.53%, respectively (p= 0.000). ROM of ankle joint increased by 8.02% (p=0.00). Nevertheless, there were no changes in the thickness of AT and fascicle length of the gastrocnemius. These results suggest that non-uniform behaviour is consistently present within the gastrocnemius and AT, and the gastrocnemius heterogeneity is reduced after SS. The stretching maneuver could be effective to increase the flexibility.


Assuntos
Tendão do Calcâneo/fisiologia , Exercícios de Alongamento Muscular/métodos , Músculo Esquelético/fisiologia , Tendão do Calcâneo/anatomia & histologia , Tendão do Calcâneo/diagnóstico por imagem , Articulação do Tornozelo/fisiologia , Módulo de Elasticidade/fisiologia , Técnicas de Imagem por Elasticidade , Feminino , Humanos , Masculino , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/diagnóstico por imagem , Amplitude de Movimento Articular/fisiologia , Adulto Jovem
16.
J Sports Sci Med ; 18(3): 471-478, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31427869

RESUMO

Blood flow restriction (BFR) training has been shown to induce favorable changes in muscle mass and strength with a considerably low training load (20 - 30% 1RM). However, it has never been evaluated if an additional post-exercise protein supplementation enhances the effects of this training regimen. Thirty healthy older men (60.1 ± 7.6 years) were enrolled in the 8-week intervention and randomly allocated to one of the following groups: low-load BFR training with protein (collagen hydrolysate) supplementation (BFR-CH), low-load BFR training with placebo (BFR-PLA), or a control group without training, but with protein supplementation (CON). Muscle cross-sectional area (CSA), muscle strength, circulating reactive oxygen species and IGF-1 were measured before and after the intervention. Muscle CSA increased in both BFR-CH and BFR-PLA groups by 6.7 ± 3.2 % (p < 0.001) and 5.7 ± 2.7 % (p < 0.001) respectively. No significant changes were observed in the CON group (1.1 ± 1.7 %, p = 0.124). Evaluation of isometric strength (p = 0.247), insulin-like growth factor 1 (p = 0.705) and the production of reactive oxygen species (pt1 = 0.229; pt2 = 0.741) revealed no significant interaction effect but a significant long-term time effect (p < 0.001). Our results demonstrate that BFR training is an effective alternative for increasing muscle CSA in older men. Although there was a trend towards greater muscle mass adaptations in the BFR-CH group, these findings showed no statistical significance. Further research with larger sample sizes is needed to confirm these results.


Assuntos
Proteínas na Dieta/administração & dosagem , Suplementos Nutricionais , Força Muscular/fisiologia , Músculo Esquelético/irrigação sanguínea , Fluxo Sanguíneo Regional/fisiologia , Treinamento de Resistência/métodos , Adaptação Fisiológica , Fatores Etários , Idoso , Colágeno/administração & dosagem , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/anatomia & histologia , Estudos Prospectivos , Espécies Reativas de Oxigênio/sangue , Coxa da Perna/anatomia & histologia
17.
Int J Sports Med ; 40(12): 789-795, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31466083

RESUMO

We investigated the effects of sling-based, suspended push-up training on muscle size and function of upper limb and abdominal muscles. Eight men conducted suspended push-ups to failure 3 sets/session, 3 sessions/week, for 8 weeks. The maximum number of push-ups during training gradually and significantly increased from the first to last training session (+92%), suggesting improved muscle endurance. After the training, muscle thickness of the elbow extensors (+16%) and flexors (+3%), as well as abdominal muscles (rectus abdominis: RA,+27%; external oblique: EO,+14%) significantly increased. No changes occurred in maximum isometric strength of elbow extension or flexion, nor in 1-repetition maximum bench press. In a follow-up experiment, electromyograms (EMGs) of RA, EO and internal oblique (IO) during suspended push-ups to failure were measured and normalized to those during maximum voluntary contraction of each muscle (% EMGmvc) in six men. EMG significantly increased when reaching failure in all muscles (RA: 46-88%, EO: 32-50%, IO: 19-52%, start-end), and was particularly high in RA. These results suggest that suspended push-up training can augment size of not only upper limb but also abdominal muscles, likely attributable to high muscle activities during exercise; however, this does not necessarily improve maximum strength after training thus warrants careful interpretation/application.


Assuntos
Músculos Abdominais/anatomia & histologia , Músculos Abdominais/fisiologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Condicionamento Físico Humano/métodos , Extremidade Superior/fisiologia , Adolescente , Adulto , Eletromiografia , Humanos , Contração Isométrica/fisiologia , Masculino , Força Muscular/fisiologia , Adulto Jovem
18.
Br J Radiol ; 92(1101): 20190143, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31298948

RESUMO

OBJECTIVES: To assess the test-retest variability of both diffusion parameters and fat fraction (FF) estimates in normal muscle, and to assess differences in normal values between muscles in the thigh. METHODS: 29 healthy volunteers (mean age 37 years, range 20-60 years, 17/29 males) completed the study. Magnetic resonance images of the mid-thigh were acquired using a stimulated echo acquisition mode-echoplanar imaging (STEAM-EPI) imaging sequence, to assess diffusion, and 2-point Dixon imaging, to assess FF. Imaging was repeated in 19 participants after a 30 min interval in order to assess test-retest variability of the measurements. RESULTS: Intraclass correlation coefficients (ICCs) for test-retest variability were 0.99 [95% confidence interval, (CI): 0.98, 1] for FF, 0.94 (95% CI: 0.84, 0.97) for mean diffusivity and 0.89 (95% CI: 0.74, 0.96) for fractional anisotropy (FA). FF was higher in the hamstrings than the quadriceps by a mean difference of 1.81% (95% CI:1.63, 2.00)%, p < 0.001. Mean diffusivity was significantly lower in the hamstrings than the quadriceps (0.26 (0.13, 0.39) x10-3 mm2s-1, p < 0.001) whereas fractional anisotropy was significantly higher in the hamstrings relative to the quadriceps with a mean difference of 0.063 (0.05, 0.07), p < 0.001. CONCLUSIONS: This study has shown excellent test-retest, variability in MR-based FF and diffusion measurements and demonstrated significant differences in these measures between hamstrings and quadriceps in the healthy thigh. ADVANCES IN KNOWLEDGE: Test-retest variability is excellent for STEAM-EPI diffusion and 2-point Dixon-based FF measurements in the healthy muscle. Inter- and intraobserver variability were excellent for region of interest placement for STEAM-EPI diffusion and 2-point Dixon-based FF measurements in the healthy muscle. There are significant differences in FF and diffusion measurements between the hamstrings and quadriceps in the normal muscle.


Assuntos
Imagem de Tensor de Difusão/métodos , Músculo Esquelético/anatomia & histologia , Adulto , Imagem Ecoplanar/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Reprodutibilidade dos Testes , Coxa da Perna/anatomia & histologia , Adulto Jovem
19.
BMC Musculoskelet Disord ; 20(1): 310, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31266496

RESUMO

BACKGROUND: Morphological variations of the EHL concern mainly the accessory tendons and the site of their insertion. The aim of our study is to present a new classification of the EHL. METHODS: Classical anatomical dissection was performed on 104 lower limbs (51 right, 53 left, fixed in 10% formalin solution). RESULTS: In the cadavers, three types of morphology (insertion and addidtional band) were observed. Type I, the most common type, was characterized by a single tendon that ends as an extensor hood on the dorsal aspect of the base of the distal phalanx of the big toe (57.7%). Type II was characterized by two distal tendons and was subdivided into three subtypes according to (A-29.9%, B-4.8% and C-5.7%). Type III was characterised by three distal tendons (two cases - 1.9%). CONCLUSION: The EHL presents high morphological variability. Knowledge of particular types of insertion is essential for both clinicians and anatomists.


Assuntos
Variação Anatômica , Músculo Esquelético/anatomia & histologia , Tendões/anatomia & histologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cadáver , Dissecação , Feminino , , Humanos , Masculino , Pessoa de Meia-Idade
20.
Gait Posture ; 73: 101-107, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31319373

RESUMO

BACKGROUND: Muscular parameters have been considered to influence gait of older adults, but it is still unclear which specific lower limb muscular parameters correlate with kinematics of overground and obstacle crossing in older adults. RESEARCH QUESTION: What lower limb muscular parameters correlate and explain kinematics of overground walking and obstacle crossing ability in the elderly? METHODS: Muscle structure was evaluated in 15 older individuals (75.4 ±â€¯5 years) through measures of architecture (muscle thickness, fascicle length, and pennation angle) and muscle quality (echo intensity) from lower limb muscles (vastus lateralis, biceps femoris, rectus femoris, tibialis anterior, and gastrocnemius medialis). Muscle function was assessed through isometric strength of hip, knee and ankle joint muscles. Gait kinematics (toe and heel clearances, step length and gait speed) was evaluated during walking with and without obstacle crossing at preferred and maximal gait speeds. Correlation and regression analyses were performed considering a significance level of 0.05. RESULTS: Isometric strength did not correlate with gait kinematics and gait speed. Tibialis anterior thickness correlated with lead limb toe clearance, and vastus lateralis thickness with gait speed and step length. Vastus lateralis echo intensity correlated with step length and gait speed. SIGNIFICANCE: Tibialis anterior and vastus lateralis muscles deserve attention in physical training to improve gait of older adults. Specifically, tibialis anterior should receive more attention on exercise programs aiming at improvement of obstacle crossing, and knee extensors when aiming at improving gait speed and step length.


Assuntos
Marcha/fisiologia , Contração Isométrica/fisiologia , Extremidade Inferior/fisiologia , Músculo Esquelético/fisiologia , Caminhada/fisiologia , Idoso , Idoso de 80 Anos ou mais , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos , Estudos Transversais , Eletromiografia , Feminino , Humanos , Masculino , Músculo Esquelético/anatomia & histologia
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