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Abstract Introduction Obesity is a major global public health issue and approximately half of the population is classified as overweight. Many studies have investigated gait modification in obese people; however, no research has been carried out in overweight subject´s gait influence. Methods The goal of this study was to identify biomechanical changes on gait in overweight subjects by the application of principal component analysis (PCA). Two groups of adults participated of this study: overweight (n = 9; 25.0 < Body Mass Index < 29.9 kg/m2), and normal-weight (n = 15; 20.0 < Body Mass Index < 24.9 kg/m2. Three-dimensional kinematics of the lower limb and ground reaction forces (GRF) were recorded during gait. PCA was performed on data. Results PCA evidenced statistical differences at the first principal component (PC) of the sagittal ankle movement, anteroposterior and mediolateral GRF, as well as at the third PC of the sagittal hip movement and mediolateral GRF. Overweight subjects walked with reduced ankle plantarflexion at toe-off and reduced hip flexion at the heel strike and at mid swing, as well as a reduced hip extension during push off. Additionally, increased anteroposterior and mediolateral GRF on overweight subjects were observed. Conclusion overweight individuals might adjust their gait characteristics in response to their increased weight to reduce overload lower limbs joints. These gait modifications pointed to a possible increase in the risk of musculoskeletal pathology in this population.

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PURPOSE: This study aimed at testing the hypothesis that positive cardiolocomotor coordination (CLC) measure occurs by chance during a running task where the heart rate (HR) is approximated to the step frequency (StepF). METHODS: The electrocardiogram and electromyogram from the right gastrocnemius lateralis muscle were continuously recorded from ten healthy young men running at a paced rhythm of 152 step/min, to monitor HR and StepF. CLC was evaluated by phase synchrograms and the index of conditional probability (iCP). Results were validated with surrogate data and a crossover approach, where the HR of one subject was related to the StepF of another one, and comparisons were made combining subjects two by two. RESULTS: Six subjects showed synchrogram structures and high iCP values (≥0.8), suggesting the occurrence of physiological entrainment, when the HR reached the SF range. In crossover analysis, phase synchrograms and iCP presented similar behavior of original data when the HR from one subject was close enough to the SF from another one. Significant iCP values in 46 of 90 comparisons (51%) were observed, including all cases crossing signals among the six positive cases. CONCLUSION: Synchrogram and iCP tools currently employed for measuring CLC are not appropriate because they indicate the occurrence of this phenomenon even among subjects who ran on different days and times of each other.

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OBJECTIVE: To assess the influence of carbohydrate and added pea protein concentrate supplementation on muscle recovery after a military operation called Leader's Reaction Test. METHODS: Twenty-four soldiers from the Brazilian Army were divided into three equal groups (n=8). They received either carbohydrate (0.8.g/kg body weight/h), carbohydrate+carbohydrate (1.0.g/kg body weight/h), or carbohydrate+protein (0.8 g/kg body weight/h of carbohydrate + 0.2 g/kg body weight/h of protein), immediately, 60, and 120 minutes after the Leader’s Reaction Test. Prior, immediately after and 24 hours after the Leader’s Reaction Test, maximal isometric strength and body composition were assessed. Blood samples were also collected for later analysis of concentrations of lactate dehydrogenase and creatine kinase. RESULTS: Twenty-four hours after the Leader's Reaction Test, maximal creatine kinase levels were significantly lower than its levels immediately after (501.00 ± 422.09 versus 275.29 ± 242.08 U/L (carbohydrate); 616.88 ± 291.45 versus 334.57 ± 191.61 U/L (carbohydrate+carbohydrate); and 636.75 ± 340.67 versus 382.88 ± 234.42 U/L (carbohydrate+protein), p=0.004). The maximal isometric strength and lactate dehydrogenase levels were not significantly different during the time trials. CONCLUSION: The present findings suggest that carbohydrate+protein co-ingestion did not improve the recovery of muscle function nor did it attenuate post-exercise muscle damage markers over carbohydrate alone. .

OBJETIVO: Avaliar a influência da suplementação com carboidratos adicionada ao concentrado proteico de ervilha na recuperação muscular, após uma operação militar prática chamada Teste de Reação de Líderes. MÉTODOS: Vinte e quatro soldados do Exército Brasileiro foram divididos em três grupos iguais (n=8). Eles receberam a suplementação com carboidrato (0,8 g/kg de peso corporal/h) ou carboidrato mais carboidrato (1,0 g/kg de peso corporal/h) ou carboidrato mais proteína (0,8 g/kg de peso corporal/h de carboidrato + 0.2 g/kg de peso corporal/h de proteína), imediatamente, 60 e 120 minutos após o Teste de Reação de Líderes. Avaliaram-se a força isométrica máxima e a composição corporal antes do Teste de Reação de Líderes, imediatamente após e 24 horas após o teste. Amostras de sangue foram coletadas para análise posterior das concentrações de lactato desidrogenase e creatina quinase. RESULTADOS: Vinte e quatro horas após o Teste de Reação de Líderes, as concentrações de creatina quinase estavam significativamente reduzidas em comparação ao momento imediatamente posterior (501.00 ± 422,09 versus 275.29 ± 242.08 U/L (carboidrato); 616.88 ± 291,45 versus 334.57 ± 191,61 U/L (carboidrato+carboidrato) e 636.75 ± 340.67 versus 382.88 ± 234,42 U/L (carboidrato+proteína), p=0,004). A força isométrica máxima e os níveis de lactato desidrogenase não foram significativamente diferentes em nenhum momento. CONCLUSÃO: Os resultados sugerem que, em comparação à ingestão do carboidrato isoladamente, a coingestão de carboidrato e proteína não melhora a recuperação da função muscular nem atenua a liberação ...

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INTRODUÇÃO: A reprodutibilidade da atividade eletromiográfica de superfície (EMG) é mais estudada em protocolos que envolvem contrações isométricas. Alguns fatores relacionados às contrações dinâmicas podem contribuir para a instabilidade do sinal mioelétrico e dificultar a reprodutibilidade da medida da EMG. OBJETIVO: Determinar a reprodutibilidade teste-reteste e quantificar o erro técnico da medida da frequência mediana (FM) e da amplitude (root mean square, RMS) da EMG, em contrações dinâmicas e estáticas. MÉTODOS: Dez sujeitos foram testados em dois dias, sendo a atividade EMG registrada na maior porção do bíceps braquial. No primeiro dia foi feito o teste de uma repetição máxima (1RM) e de contração voluntária máxima (CVM). No segundo dia foram realizadas duas séries de 10 contrações dos flexores do cotovelo com 75% de 1RM, entremeadas por 1 h em repouso. Antes de cada série foi realizada uma CVM. RESULTADOS: Para a FM e RMS foi observado alto coeficiente de correlação intraclasse para o sinal do bíceps braquial (CCI = 0,90-0,98 para a FM; CCI = 0,89-0,94 para o RMS) e de baixo para moderado coeficiente de variação (CV = 2,5-6,2% para a FM; CV = 14,6-16,3% para o RMS) em ambos os testes. Não foi observada diferença significativa entre teste e reteste (p > 0,05). CONCLUSÃO: A FM e o RMS apresentam alta confiabilidade e baixo a moderado erro em contrações estáticas e dinâmicas, possibilitando o uso da EMG para investigação da fadiga e de desordens neuromusculares.

INTRODUCTION: Reproducibility of electromyographic activity (EMG) is the most studied in protocols involving isometric contractions. Some factors related to dynamic contractions may contribute to the instability of the myoelectric signal and affect the reproducibility of the measurement of EMG. OBJECTIVE: To determine the test-retest reproducibility and quantify the technical error of the measurement of the median frequency (MF) and amplitude (root mean square, RMS) of the surface EMG in static and dynamic contractions. METHODS: Ten subjects were tested in two days with the EMG activity recorded for the greatest portion of the biceps brachii tendon. In the first day the subjects did one test of maximum repetition (1MR) and maximal voluntary contraction (MVC). On the second day the subjects performed two sets of 10 dynamic contractions of the elbow flexors at 75% of 1MR interspersed by 1 h at rest. Before each set one MVC was performed. RESULTS: For both MF and RMS, was observed high intraclass reliability for biceps brachii (ICC = 0.90-0.98 for MF; ICC = 0.89-0.94 for RMS) and low to moderate coefficient of variation (CV = 2.5-6.2% for MF; CV =14.6-16.3% for RMS) in both tests. No significant difference between test and retest was found (p>0.05). CONCLUSION: The MF and RMS have high reliability and low to moderate error in static and dynamic contractions, enabling the use of EMG for the investigation of fatigue and neuromuscular disorders.

INTRODUCCIÓN: La reproducibilidad de la actividad electromiográfica de superficie (EMG) es más estudiada en protocolos que involucran contracciones isométricas. Algunos factores relacionados con las contracciones dinámicas pueden contribuir para la inestabilidad de la señal mioeléctrica y dificultar la reproducibilidad de la medida de la EMG. OBJETIVO: Determinar la reproducibilidad prueba-nueva prueba y cuantificar el error técnico cuanto a la medida de la frecuencia mediana (FM) y de la amplitud (root mean square, RMS) de la EMG de superficie, en contracciones dinámicas y estáticas. MÉTODOS: diez individuos fueron examinados en dos días, siendo la actividad EMG registrada en el área más grande del bíceps braquial. En el primer día, se hizo la prueba de una repetición máxima (1RM) y de contracción voluntaria máxima (CVM). En el segundo día, se realizaron dos series de 10 contracciones de los flexores del codo, con 75% de 1RM, alternadas por 1 hora en reposo. Antes de cada serie, se hizo una CVM. RESULTADOS: Para la FM y el RMS se observó un alto coeficiente de correlación para la señal del bíceps braquial (CCI = 0,90-0,98 para la FM; CCI = 0,89-0,94 para el RMS) y un coeficiente de variación de bajo para moderado (CV = 2,5-6,2% para la FM; CV = 14,6-16,3% para el RMS) en ambas pruebas. No se observó una diferencia significativa entre prueba y nueva prueba (p > 0,05). CONCLUSIÓN: La FM y el RMS presentan alta confiabilidad, y error de bajo a moderado en contracciones estáticas y dinámicas, posibilitando el uso de la EMG para investigación de la fatiga y de desórdenes neuromusculares.

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CONTEXTO: A prática de esportes apresenta efeitos benéficos para o sistema cardiorrespiratório e muscular, para a função comportamental e para a saúde mental. Entretanto, não se sabe o papel do esporte de alto nível na construção de perfis resilientes. OBJETIVOS: O objetivo do presente estudo foi comparar resiliência, qualidade de vida e ansiedade de ex-atletas de alto rendimento de ginástica artística, de outros esportes e indivíduos não atletas. MÉTODOS: Participaram do estudo ex-atletas de ginástica artística (n = 17), de outras modalidades (n = 15) e indivíduos não atletas (n = 30). Foram utilizadas as seguintes escalas e questionários: Inventário de Depressão de Beck, Inventário de Ansiedade Traço e Estado (IDATE T e E), Escala de Resiliência e Questionário de Qualidade de Vida SF-36®. RESULTADOS: Foi observada diferença significativa entre os grupos na resiliência (p = 0,001), IDATE T (p = 0,049), estado geral de saúde (p = 0,044) e aspectos emocionais da qualidade de vida (p = 0,002), indicando que o grupo de ex-atletas apresentou maior resiliência e melhor aspecto emocional que não atletas. CONCLUSÃO: O esporte parece favorecer a construção de um perfil mais resiliente, além de contribuir para melhor qualidade de vida.

BACKGROUND: The practice of sports has beneficial effects on cardiorespiratory and muscle systems, behavioral function, and mental health. However, the influence of elite sports on the development of resilience is not known. OBJECTIVES: The objective of the present study was to compare resilience, quality of life, and anxiety in ex-athletes of artistic gymnastic and other sports with non-athletic individuals. METHODS: Ex-artistic gymnastics athletes (n = 17), ex-athletes of other sports (n = 15), and non-athletic individuals (n = 30) were recruited. Structured anamneses as well as depression, anxiety, resilience and quality of life scales were applied in all groups. RESULTS: Significant difference between groups were found in resilience (p = 0.001), anxiety (p = 0.049), general health status (p = 0.044), and emotional aspects of quality of life (p = 0.002). Ex-athletes showed greater resilience and better quality of life regarding to emotional aspects than non-athletes. DISCUSSION: Sport seems to contribute to the development of a more resilient profile and better quality of life.

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